Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript addresses a clinically important and insufficiently quantified aspect of neonatal anatomy: the spatial relationship between anterior abdominal wall vasculature and commonly used laparoscopic landmarks. The integration of superficial, deep, and visceral topography into a unified grid-based analysis is a notable strength, and the attempt to translate anatomical findings into practical surgical guidance is commendable. The study is carefully structured, and the dataset appears systematically collected. That said, several aspects of the manuscript would benefit from clarification, refinement, and more cautious interpretation to ensure methodological robustness and appropriate clinical translation.

First, the characterization of the sample requires greater precision. The mean weight of the cohort (1.77 ± 1.16 kg) is considerably lower than that of a typical term neonate, and this raises important questions regarding gestational age distribution and clinical representativeness. If gestational age data are available, they should be reported. If not, this limitation should be explicitly acknowledged. It is particularly important to clarify whether the sample reflects predominantly premature neonates, as abdominal wall thickness, organ size, and vessel position may differ meaningfully between preterm and term populations. At present, the discussion refers broadly to “the neonatal population,” and this phrasing may overstate the generalizability of the findings. A more measured framing would strengthen the manuscript.

Second, the statistical approach to data handling warrants clarification. The removal of outliers using Z-scores greater than ±3 is briefly mentioned, but the manuscript does not indicate how many measurements were excluded or from which anatomical landmarks. In anatomical research, extreme values may represent true biological variation rather than measurement error. The authors should report the number and distribution of excluded data points and justify the exclusion in anatomical rather than purely statistical terms. Ideally, a brief sensitivity analysis (or at least a statement confirming that exclusion did not materially alter the overall interpretation) would improve transparency.

Related to this, the unit of analysis should be clearly defined. Each specimen contributed multiple directional measurements across numerous anatomical landmarks. It is not entirely clear whether confidence intervals were calculated at the specimen level or at the level of individual directional measurements treated as independent observations. Given the structured grid design, some degree of within-specimen correlation is inevitable. Even if the analysis remains descriptive, a brief explanation of how clustering was handled—or why it was not considered necessary—would improve methodological clarity.

The central conclusion of a “relatively avascular midline corridor” is supported by the reported mean distances to deep vessels; however, the language occasionally becomes stronger than the data warrant. The reported minimal circumferential distances in the midline are on the order of 6–8 mm, with substantial variability in some cases. While these distances are greater than those observed laterally, they do not imply absence of risk. It would strengthen the manuscript to explicitly define what constitutes a clinically meaningful safety margin in the context of 3–5 mm trocars. The current phrasing may inadvertently suggest categorical safety rather than relative risk reduction. Reframing this as a statistically and anatomically “greater mean distance compared to lateral landmarks” would preserve the clinical message while avoiding overstatement.

The sections proposing neonatal adaptations of Palmer’s point are innovative and thought-provoking but require more cautious presentation. The derivation of specific millimetric thresholds (e.g., 24.21 mm below the costal margin) from upper 95% confidence limits implies a degree of procedural precision that may not be achievable in clinical practice. Furthermore, the study was conducted on formalin-fixed, non-distended abdominal walls without pneumoperitoneum. These conditions may alter organ compliance and spatial relationships compared to live neonates. The authors do acknowledge fixation and absence of insufflation as limitations, but the clinical recommendations in this section should be framed more explicitly as hypothesis-generating rather than practice-changing. Emphasizing the need for in vivo ultrasonographic validation before clinical implementation would enhance scientific balance.

The inter-observer and intra-observer analyses are a strength of the manuscript. However, the interpretation of statistically significant differences as “not clinically significant” would benefit from additional contextualization. When minimal distances to vessels are sometimes in the range of 1–2 mm, a systematic difference of approximately 1 mm between observers may represent a nontrivial proportion of the measured safety margin. A brief comparison between measurement discrepancies and typical trocar diameters would help readers judge clinical relevance more concretely.

With regard to presentation, the tables are comprehensive but dense. Consider whether key findings—particularly minimal circumferential distances—could be summarized in a simplified comparative table highlighting the most and least favorable anatomical points. This would improve readability for surgeons who may focus primarily on applied implications. Additionally, in the Methods section, please clarify whether image calibration using the scale reference was performed for each individual image or applied globally across images.

The Introduction is generally well constructed and adequately referenced. The literature synthesis appropriately situates the work within pediatric laparoscopy and vascular injury risk. However, one or two recent high-resolution imaging or Doppler-based mapping studies in neonates (if available) could further strengthen the positioning of this work within contemporary anatomical research.

The Discussion is thoughtful and clinically engaged. Nonetheless, some paragraphs—particularly those addressing ergonomics and triangulation—could be tightened to improve clarity and avoid repetition. Minor language refinements throughout the manuscript would also enhance readability, although the overall English is understandable.

In summary, this is a valuable and carefully conducted anatomical study with meaningful clinical implications. Strengthening the statistical transparency, refining the scope of generalization, and moderating certain procedural recommendations will substantially improve the manuscript’s rigor and impact. With these revisions, the work has strong potential to make a durable contribution to neonatal surgical anatomy and minimally invasive practice.

Comments on the Quality of English Language

The manuscript is generally written in clear and understandable English, and the scientific content can be followed without major difficulty. However, several sections would benefit from stylistic refinement to improve precision, conciseness, and flow. In particular, some sentences in the Discussion are overly long and contain multiple embedded clauses, which occasionally obscure the main argument. There are also minor inconsistencies in phrasing and occasional grammatical issues (e.g., possessive forms, article usage, and minor typographical inconsistencies).

I recommend a careful language revision focused on tightening sentence structure, ensuring consistency in terminology (especially anatomical descriptors), and reducing redundancy. A focused professional language edit would further enhance clarity, but substantial rewriting is not required.

Author Response

Reviewer 1

This manuscript addresses a clinically important and insufficiently quantified aspect of neonatal anatomy: the spatial relationship between anterior abdominal wall vasculature and commonly used laparoscopic landmarks. The integration of superficial, deep, and visceral topography into a unified grid-based analysis is a notable strength, and the attempt to translate anatomical findings into practical surgical guidance is commendable. The study is carefully structured, and the dataset appears systematically collected. That said, several aspects of the manuscript would benefit from clarification, refinement, and more cautious interpretation to ensure methodological robustness and appropriate clinical translation.

Response:

The authors thank the reviewer for his positive comments and his time and dedication to the peer-review process.

 

Comment 1

First, the characterization of the sample requires greater precision. The mean weight of the cohort (1.77 ± 1.16 kg) is considerably lower than that of a typical term neonate, and this raises important questions regarding gestational age distribution and clinical representativeness. If gestational age data are available, they should be reported. If not, this limitation should be explicitly acknowledged. It is particularly important to clarify whether the sample reflects predominantly premature neonates, as abdominal wall thickness, organ size, and vessel position may differ meaningfully between preterm and term populations. At present, the discussion refers broadly to “the neonatal population,” and this phrasing may overstate the generalizability of the findings. A more measured framing would strengthen the manuscript.

Response:

The authors agree that referring to "the neonatal population" overstates the generalizability of the findings. The text has been modified to acknowledge this limitation and reframe the applicability of the findings toward low-birth-weight, where the risk of spatial vascular injury is paradoxically the highest.

Action taken:

The following text has been added to the Limitations of the study section.

"Exact gestational ages were not available for this very low birth weight group. Therefore, the quantitative results should be interpreted with caution when applying them to full-term, normal-weight neonates.”

Furthermore, instances of the phrase "the neonatal population" throughout the abstract and discussion have been systematically revised to the “low-birth-weight” neonatal sample.

 

Comment 2

Second, the statistical approach to data handling warrants clarification. The removal of outliers using Z-scores greater than ±3 is briefly mentioned, but the manuscript does not indicate how many measurements were excluded or from which anatomical landmarks. In anatomical research, extreme values may represent true biological variation rather than measurement error. The authors should report the number and distribution of excluded data points and justify the exclusion in anatomical rather than purely statistical terms. Ideally, a brief sensitivity analysis (or at least a statement confirming that exclusion did not materially alter the overall interpretation) would improve transparency.

Response:

The reviewer's perspective on the distinction between true biological variation and statistical error in anatomical research is highly appreciated. Removing the anatomical data points that exceeded ±3 Z-score helps improve the accuracy of statistical analysis by eliminating measurement errors, recording mistakes (the authors ensured measurements were recorded correctly before exclusion), or extreme biological anomalies that distort the mean and standard deviation. This was done to ensure results represent typical structural patterns.

Action taken:

The Statistical analyses section has been updated.

"To reduce recording mistakes and extreme biological measurements impacting the mean and standard deviation, all Z-scores that were greater than 3 or less than -3 were removed from the data set. This was to ensure the quantitative results accurately represent the typical structural and vascular patterns of the low-birth-weight neonatal anterior abdominal wall.”

Comment 3

Related to this, the unit of analysis should be clearly defined. Each specimen contributed multiple directional measurements across numerous anatomical landmarks. It is not entirely clear whether confidence intervals were calculated at the specimen level or at the level of individual directional measurements treated as independent observations. Given the structured grid design, some degree of within-specimen correlation is inevitable. Even if the analysis remains descriptive, a brief explanation of how clustering was handled—or why it was not considered necessary—would improve methodological clarity.

Response:

In this study, the unit of analysis was the individual measurement taken at each anatomical landmark, with each specimen contributing multiple measurements across the predefined grid. We acknowledge that some degree of within-specimen correlation is inherent in this design. However, the analysis was conducted within a descriptive anatomical framework, in which each measurement represents a distinct spatial relationship between a landmark and its nearest vascular structure. As such, measurements were pooled to characterise overall anatomical patterns rather than to perform inferential statistical comparisons. This approach, and its limitations, have now been clarified in the manuscript, and the findings are interpreted as descriptive anatomical trends rather than statistically independent observations.

Action taken:

The Statistical analyses section has been updated.

“It should be noted that each specimen contributed multiple directional measurements across predefined anatomical landmarks. The unit of analysis was therefore the individual measurement at each anatomical point. While some degree of within-specimen correlation is inherent to this design, the analysis was conducted within a descriptive anatomical framework, where each measurement represents a distinct spatial relationship within the grid. As such, measurements were pooled to characterise overall anatomical patterns, and clustering effects were not formally modelled. The findings should therefore be interpreted as descriptive of anatomical trends rather than as statistically independent observations.”

 

Comment 4

The central conclusion of a “relatively avascular midline corridor” is supported by the reported mean distances to deep vessels; however, the language occasionally becomes stronger than the data warrant. The reported minimal circumferential distances in the midline are on the order of 6–8 mm, with substantial variability in some cases. While these distances are greater than those observed laterally, they do not imply absence of risk. It would strengthen the manuscript to explicitly define what constitutes a clinically meaningful safety margin in the context of 3–5 mm trocars. The current phrasing may inadvertently suggest categorical safety rather than relative risk reduction. Reframing this as a statistically and anatomically “greater mean distance compared to lateral landmarks” would preserve the clinical message while avoiding overstatement.

Response:

The authors admit that describing the term "avascular" as overly definitive could be misleading. An average distance of 6.84 mm from a central landmark offers a safety margin, but inserting a surgical instrument of 3 mm or 5 mm (such as a pediatric trocar) at that point will occupy 1.5 mm to 2.5 mm of that margin, respectively. As a result, the actual space before risking vascular injury is smaller. Although this indicates a significantly lower risk compared to the 1-2 mm lateral distances measured, it does not guarantee protection from vascular damage. The manuscript has been updated to discuss the risk reduction relative to these measurements.

Action taken:

The phrase "avascular” midline corridor has been globally replaced with "reduced vascular" or "presence of vasculature was reduced “. Phrasing such as relatively avascular was retained.

 

Comment 5

The sections proposing neonatal adaptations of Palmer’s point are innovative and thought-provoking but require more cautious presentation. The derivation of specific millimetric thresholds (e.g., 24.21 mm below the costal margin) from upper 95% confidence limits implies a degree of procedural precision that may not be achievable in clinical practice. Furthermore, the study was conducted on formalin-fixed, non-distended abdominal walls without pneumoperitoneum. These conditions may alter organ compliance and spatial relationships compared to live neonates. The authors do acknowledge fixation and absence of insufflation as limitations, but the clinical recommendations in this section should be framed more explicitly as hypothesis-generating rather than practice-changing. Emphasizing the need for in vivo ultrasonographic validation before clinical implementation would enhance scientific balance.

Response:

The authors agree with the reviewer's cautious approach. Calculating a surgical threshold implies an unrealistic level of intraoperative precision, particularly on the highly pliable surface of a neonatal abdomen. Furthermore, the lack of pneumoperitoneum during the cadaveric measurements fundamentally alters the topography. In vivo, insufflation creates a radial expansion of the abdominal wall, actively lifting the parietal peritoneum away from the underlying viscera, which likely alters these calculated margins. The recommendations regarding Palmer's point have been simplified and explicitly labeled as theoretical, requiring clinical validation prior to adoption.

Action taken:

The discussion regarding Palmer's point in the Discussion section has been expanded:

"As such, the neonatal equivalent of Palmer's point, from the anatomical finding from this sample, suggests a blind Veress needle insertion, where the liver and stomach would not be in danger, would be below 2.5 cm below the costal margin in the left midclavicular line, considering the upper limit of the 95% CI for the stomach. This anatomical finding should be regarded as a hypothesis-generating guideline rather than a practice-changing guideline. The baseline measurements were obtained on non-distended, flaccid abdominal walls. The induction of pneumoperitoneum in a live patient dynamically alters parietal-visceral spatial relationships. Therefore, these static cadaveric thresholds must undergo clinical validation before being reliably implemented in routine clinical practice."

Comment 6

The inter-observer and intra-observer analyses are a strength of the manuscript. However, the interpretation of statistically significant differences as “not clinically significant” would benefit from additional contextualization. When minimal distances to vessels are sometimes in the range of 1–2 mm, a systematic difference of approximately 1 mm between observers may represent a nontrivial proportion of the measured safety margin. A brief comparison between measurement discrepancies and typical trocar diameters would help readers judge clinical relevance more concretely.

 

Response:

The reviewer correctly points out that in the lateral midclavicular lines, where the true vascular distance is often documented at 1.16 ± 1.27 mm (e.g., point 'p'), a 1 mm observational discrepancy represents an error magnitude of nearly 100%. The authors have added relevant measurements for easier review by the reader.

Action taken:

The section “Inter-observer and intra-observer error analysis” has been updated accordingly.

“The intra-observer error analysis indicated no clinically significant difference between the principal investigator's initial observations and those made to test repeatability (p > 0.05). The intra-observer error analysis also showed no biases in the measured variables. The interobserver error analysis of accuracy revealed some bias in the measurement (p < 0.05). As such, individual analysis of the measurement pairs was conducted and indicated bias at point “p” (1.16 ± 1.27 mm; p = 0.01), at the intersection of the left midclavicular line and the horizontal line through McBurney’s point for measurement made for the deep vascular structures of the anterior abdominal wall. The second observer’s measurements were consistently above those made by the principal investigator, with the 95% CI of the difference ranging from -0.21 mm to -0.06 mm, with a mean difference of -0.14 mm. Considering the close relationship to zero, the authors do not consider the bias clinically significant when referring to a typical trocar diameter. Moreover, when comparing the internal vasculature and organs measurements of the co-author and the principal investigator, numerous measurement biases were observed between the pair (p < 0.05). The difference between the pair was 1.67 mm at point “I” medially towards the umbilical vein (20.97 ± 6.39 mm), the difference was 1.16 mm at point “u” medially (9.44 ± 3.61 mm), and the difference of 1.37 mm was observed from the costal border to the inferior margin of the liver (17.34 ± 8.24 mm). All these differences could be considered as small and insignificant when considering the measurement. However, all three measurements the co-author obtained had a value smaller than the principal investigator’s original measurements. Although there is a strong bias, the authors determined that the differences are not clinically significant, given the proximity to the zero value.

 

Comment 7

With regard to presentation, the tables are comprehensive but dense. Consider whether key findings—particularly minimal circumferential distances—could be summarized in a simplified comparative table highlighting the most and least favorable anatomical points. This would improve readability for surgeons who may focus primarily on applied implications. Additionally, in the Methods section, please clarify whether image calibration using the scale reference was performed for each individual image or applied globally across images.

 

Response:

The authors agree with the reviewer's suggestion to include a handy “quick-review” table to enhance the manuscript's utility for clinicians. Additionally, the manuscript has been updated to explicitly state that image calibration was performed individually for every photograph to account for any microscopic variations in focal depth or tripod orientation.

 

Action taken:

A new table and figure have been added to the Discussion:

Table 4: Mean Circumferential Distances to Deep Vasculature from key anatomical landmarks

and

Figure 5: Mean Circumferential Distances to Deep Vasculature from key anatomical landmarks

The Materials and Methods section has been amended:

"Each photograph was calibrated with the in-frame metric scale to minimize measurement errors caused by slight variations in tripod height, camera angle, or focal depth during different dissections."

 

Comment 8

The Introduction is generally well constructed and adequately referenced. The literature synthesis appropriately situates the work within pediatric laparoscopy and vascular injury risk. However, one or two recent high-resolution imaging or Doppler-based mapping studies in neonates (if available) could further strengthen the positioning of this work within contemporary anatomical research.

Response:

The authors appreciate the reviewers' comments, and as also suggested by Reviewer 3, Comment 9, the discussion has been updated to include adult-derived advanced imaging studies.

Action taken:

The discussion section has been expanded to include:

 

Comment 9

The Discussion is thoughtful and clinically engaged. Nonetheless, some paragraphs—particularly those addressing ergonomics and triangulation—could be tightened to improve clarity and avoid repetition. Minor language refinements throughout the manuscript would also enhance readability, although the overall English is understandable.

Response:

The manuscript has undergone a thorough structural and linguistic edit.

Action taken:

The discussion has been condensed and refocused.

 

Summary Comment

In summary, this is a valuable and carefully conducted anatomical study with meaningful clinical implications. Strengthening the statistical transparency, refining the scope of generalization, and moderating certain procedural recommendations will substantially improve the manuscript’s rigor and impact. With these revisions, the work has strong potential to make a durable contribution to neonatal surgical anatomy and minimally invasive practice.

Response:

We sincerely appreciate the reviewer's positive comments. The reassurance and validation for the hard work put into the research are truly valued.

 

Comments on the Quality of English Language

The manuscript is generally written in clear and understandable English, and the scientific content can be followed without major difficulty. However, several sections would benefit from stylistic refinement to improve precision, conciseness, and flow. In particular, some sentences in the Discussion are overly long and contain multiple embedded clauses, which occasionally obscure the main argument. There are also minor inconsistencies in phrasing and occasional grammatical issues (e.g., possessive forms, article usage, and minor typographical inconsistencies).

 

I recommend a careful language revision focused on tightening sentence structure, ensuring consistency in terminology (especially anatomical descriptors), and reducing redundancy. A focused professional language edit would further enhance clarity, but substantial rewriting is not required.

Response:

The authors thank the reviewers for their helpful feedback on the manuscript's language. A thorough language review was performed, mainly targeting excessively long sentences with many embedded clauses. Unnecessary adjectives were removed, and anatomical terms were standardized, with references consistently using "inferior epigastric artery" instead of switching between that and "deep epigastric."

Action taken:

Revision of the manuscript was performed. Sentence structures in the Discussion were simplified, transitioning from complex compound sentences to direct, declarative statements. Terminology was standardized across all sections and figure legends.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

It is a manuscript that compiles extensive anatomical dissection work in newborns with a very clear objective: to locate a safe surgical access point. The text reflects a well-structured anatomical technique executed by the authors.

I would like to make a series of recommendations that would improve the text of this significant anatomical work:
1. The manuscript as a whole may be too long to read and could be shortened in some sections, such as the introduction and the description of the technique in lines 57 to 68.
2. Lines 142-144: The points are already referenced in Figure 2 and can be summarised.
3.      Figure 5 should go in section 3.2, where it belongs, as it describes deep vascularisation.
4.      The data in lines 271-275 cannot be traced back to any table.
5.      I would recommend making the tables more fragmented to make them easier to read, for example, separating the results by area.

Author Response

It is a manuscript that compiles extensive anatomical dissection work in newborns with a very clear objective: to locate a safe surgical access point. The text reflects a well-structured anatomical technique executed by the authors. I would like to make a series of recommendations that would improve the text of this significant anatomical work:

Response:

We appreciate the reviewer's positive feedback and thank them for their time and effort in the peer-review process.

 

Comment 1

The manuscript as a whole may be too long to read and could be shortened in some sections, such as the introduction and the description of the technique in lines 57 to 68.

Response:

The authors agree that the text could be refined and that redundancies could be reduced throughout the manuscript. For example, the background mechanics of inducing a pneumoperitoneum, detailed in lines 57–68, were overly protracted and strayed from the primary anatomical focus of the manuscript. This section has been condensed to focus on the immediate risks of umbilical access and CO2 embolism.

Action taken:

The text originally occupying lines 57–68 has been streamlined.

 

Comment 2

Lines 142-144: The points are already referenced in Figure 2 and can be summarised.

Response:

The redundant textual listing of the landmark points has been removed to significantly improve the narrative flow of the methodology section.

Action taken:

Lines 142-144 have been deleted, and the preceding sentence was modified to direct the reader to figure 2:

"Using blunt dissection, the fat and fascia overlying the superficial vascular structures were carefully removed until the vascular structures were clearly visible. After all the required structures had been identified, the anatomical planes and landmarks were marked, as detailed in Figure 2.”

 

Comment 3

Figure 5 should go in section 3.2, where it belongs, as it describes deep vascularisation.

Response:

The authors thank the reviewer for pointing out this formatting issue. Following Reviewer 3's suggestion, Figure 5 has been combined with Figure 4 (now labelled as Figure 3), showing the kernel density plots for the deep vascular structures alongside those of the superficial vascular structures. This update helps the reader easily compare the superficial and deep kernel density plots.

Action taken:

Figure 5 and Figure 4 have been combined, and are now representative of Figure 3 A and B.

 

Comment 4

The data in lines 271-275 cannot be traced back to any table.

Response:

The reviewer correctly noted that the minimal circumferential distance data for points 'k', 'w', 'x', and 'y' (together with all other circumferential distances) have been omitted from the tables within the manuscript. The original draft of the manuscript had these distances in separate tables, but, to reduce the number of tables, the authors decided to mention the distances in the text and remove the tables. As per the reviewer’s suggestion (together with Reviewer 1, Comment 7), we have included a handy “quick-review” table to enhance the manuscript's utility for clinicians

Action taken:

A new table and figure have been added to the Discussion:

Table 4: Mean Circumferential Distances to Deep Vasculature from key anatomical landmarks

and

Figure 5: Mean Circumferential Distances to Deep Vasculature from key anatomical landmarks

 

Comment 5

I would recommend making the tables more fragmented to make them easier to read, for example, separating the results by area.

Response:

Tables 1 and 2 were undeniably dense. Following the reviewer's structural suggestion, the data has been fragmented geographically. The data for both superficial and deep vascular structures are now divided to be present “above the umbilicus”, “at the umbilicus” and “below the umbilicus”. This formatting overhaul drastically improves readability and rapid data retrieval for the reader.

 

Action taken:

Table 1 and Table 2 have each been divided into three separate tables (Tables 1 to 6):

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The overall study is of a great value. However, the presentation of the article is too long with redundant sentences, wording and paragraphs. Shortening it and keeping it practical to the main points and essential informative statements would enhance its layout and presentation to the readers.  

Attached is my detailed comments in the PDF.

Comments for author File: Comments.pdf

Author Response

The overall study is of a great value. However, the presentation of the article is too long with redundant sentences, wording and paragraphs. Shortening it and keeping it practical to the main points and essential informative statements would enhance its layout and presentation to the readers.

Response:

We thank the reviewer for his positive comments.

 

Abstract – Conclusions

Comment 1

Line-32: “To the author’s knowledge this study presents the first quantitative 32 analysis of the blood vessels in the neonatal anterior abdominal wall”. This statement is redundant for an abstract; I suggest removing it.

Response:

The authors agree. The statement has been removed to maintain an objective presentation of the anatomical findings.

Action taken:

The phrase "To the author's knowledge this study presents the first quantitative analysis of the blood vessels in the neonatal anterior abdominal wall" has been deleted entirely from the Abstract.

 

Introduction

Comment 2

I suggest adding a brief paragraph of the anatomy background of the relevant of the anterior abdominal wall vasculature. I suggest dividing the paragraphs by some subheadings highlighting the two main core aspects: The anatomy background, and the Surgical approach.

Response:

The Introduction has been divided using the suggested subheadings. Furthermore, a detailed paragraph regarding the foundational anatomy of the vasculature has been added.

Action taken:

Subheadings Anatomical Background and Surgical Approach were added to the Introduction.

Under Anatomical Background, the following text was added:

"Most of the arterial blood supply to the anterior abdominal wall comes from the su-perior, inferior, and superficial epigastric arteries, along with the intercostal arteries and the deep and superficial circumflex arteries. The superior epigastric artery (TA2: arteria epigastrica superficialis), a terminal branch of the internal thoracic artery (TA2: arteria thoracica interna), descends posterior to the rectus abdominis muscle (TA2: musculus rectus abdominis). It eventually anastomosing with the inferior epigastric artery (TA2: ar-teria epigastrica inferior), which originates from the external iliac artery (TA2: arteria ilia-ca externa) [4]. Numerous perforators pass through the rectus abdominis muscles, providing blood supply to the overlying skin [5]. The superficial epigastric artery (TA2: arteria epigastrica superficialis) originates from the femoral artery, courses subcutane-ously, and supplies the superficial anterior abdominal wall [4]. While the macroscopic course of these vessels is well-documented in adults [6-9], the topography of these vessels in the peadiatric abdomen remains under-reported. Awareness of vascular topography could help clinicians avoid vascular trauma during percutaneous instrumentation."

 

Materials and Methods

Comment 3

Lines: 110-120. The 2nd paragraph is redundant as these are common dissections tools and ordinary photo documentation. I suggest removing it especially that the steps are already listed in the following paragraphs.

Response:

The paragraph detailing the routine use of standard forceps, scalpel blades, and basic dissecting tools has been removed to streamline the methodology.

Action taken:

The paragraph spanning lines 112–115 detailing the microdissection tools (fine forceps, number 15 scalpel blade, Bonn scissors) has been deleted.

 

Results

Comment 4

Lines: 230-232. This seemed some typo, forgotten to be removed note! Lines: 234-237. The overall text is quite long. Consider shortening it to keep the findings concise to the main points by reducing the long non-essential descriptive statements. This paragraph belongs in the Materials and Methods sections. Please rearrange it.

Response:

The authors apologise for this embarrassing formatting error. The text ("This section may be divided by subheadings. It should provide a concise and precise description...") was an inadvertent retained from the journal's formatting template. The authors sincerely apologize for this oversight. The Results section has been thoroughly audited for verbosity. Long, narrative descriptions of the kernel density plots that reiterated the metric data already presented in the figures have been shortened.

Action taken:

Lines 230-232 have been entirely removed from the manuscript. Descriptive redundancies within Sections 3.1.1 through 3.1.3 have been shortened.

 

Comment 5

Lines: 546-566 “3.4 Inter-observer and intra-observer error analysis”. It doesn’t fit well under the results section. Consider summarizing it and incorporating its intra-observer error with the text in Line-209 “Statistical Analysis”; and incorporating the elaboration on its bias clinically non-significant under the discussion section.

Response:

The authors truly appreciate the reviewers' feedback and suggestions. However, the authors would prefer that the discussion focus on the anatomical findings and their clinical significance, rather than on statistical results from the inter- and intra-observer analyses. As such, we have kept the “Inter-observer and intra-observer error analysis” within the results section. However, the content was refined in hopes of satisfying Reviewer 1 and Reviewer 3.

 

Action taken:

Refined content within the results section.

 

Discussion

Comment 6

Consider dividing the text into some subsections for easier navigation for the readers.

Response:

After considering suggestions from Reviewer 1, edits were made to the discussion to focus the discussion on trocar placement. We hope the changes made to the Discussion section, transforming a previously dense block of text, are satisfactory.

Action taken:

The discussion section has undergone a thorough review and edits to refine and keep the discussion concise.

 

Conclusions

Comment 7

Lines: 701-714. Consider shortening and reformulating to give an informative main outcome point of the study implication in the clinical practice. A concluding statement/remark. Please elaborate on the potential post-surgical correlation considering risk of abdominal wall hernias.

Response:

The original Conclusions section was overly repetitive of the Results. It has been refined to deliver a summary of the clinical implications derived from the anatomical data.

Action taken:

Changes were made to the Conclusions section.

 

Figures

Comment 8

Figure 1: I suggest cropping images C and F to limit cadaveric exposure to the essential relevant body region (Trunk without the head and the periphery, similar to Figure 2 presentation). It binds better with ethical consensus of cadaveric display. Figures 2 and 3: Consider combing it into one figure of A and B. It gives easier visual comparison of the two layers (similar to figure 6 presentation). Figures 4 and 5: Consider combing it into one figure of A and B. It gives easier visual comparison of the two layers (similar to figure 6 presentation).

Response:

The authors are highly grateful for this critical reminder regarding the ethical display of human tissue. Figures 1C and 1F have been securely cropped to obscure the periphery and focus exclusively on the anatomical region of interest. Combining the figures facilitates a much more cohesive visual analysis, allowing the reader to immediately compare the superficial layer against the deep layer without turning pages.

Action taken:

Figures 1C and 1F have been replaced with cropped versions focusing on the anterior abdominal wall.

Figure 2 and Figure 3 have been consolidated into a single two-panel composite image (Figure 2).

Figure 4 and Figure 5 have been consolidated into a single two-panel composite image (Figure 3). Subsequent figures have been renumbered accordingly.

 

References

Comment 9

It’s a bit shorter than expected for the topic. Even though its scares considering neonatal cases, there are much more relevant articles addressing the anatomy of the abdominal wall vasculature and articles discussing the addressing procures in adults where it supports the introduction and discussion sections.

Examples:

1. Bowness J, Seeley J, Varsou O, et al. Arterial Anatomy of the Anterior Abdominal Wall: Evidence-Based Safe Sites for Instrumentation Based on Radiological Analysis of 100 Patients. Clin Anat.2020;33(3):350-354. doi:10.1002/ca.23463
2. Kostov S, Dineva S, Kornovski Y, Slavchev S, Ivanova Y, Yordanov A. Vascular Anatomy and Variations of the Anterior Abdominal Wall - Significance in Abdominal Surgery. Prague Med Rep.2023;124(2):108-142. doi:10.14712/23362936.2023.9
3. Le Saint-Grant A, Taylor A, Varsou O, Grant C, Cezayirli E, Bowness J. Arterial anatomy of the anterior abdominal wall: Ultrasound evaluation as a real-time guide to percutaneousinstrumentation. Clin Anat. 2021;34(1):5-10. doi:10.1002/ca.23578
4. Meyerov J, Ram R, Grinsell D. Refining the abdominal wall perforasome with clinical application. JPlast Reconstr Aesthet Surg. 2025;105:283-291. doi:10.1016/j.bjps.2025.04.024
5. Rozen WM, Ashton MW, Taylor GI. Reviewing the vascular supply of the anterior abdominal wall: redefining anatomy for increasingly refined surgery. Clin Anat. 2008;21(2):89-98.doi:10.1002/ca.20585

Response:

The authors appreciate the reviewers' suggestions, and the introduction and discussion (as also suggested by Reviewer 1, Comment 8) have been adapted to include some of the references provided. The literature has been expanded.

Action taken:

The following in-text citations have been added to the text and Reference list. They have been added the new Anatomical Background section of the Introduction (as detailed in Response 3 above) and into the Discussion regarding lateral vascular density:

"4.          Jelinek LA, Scharbach S, Kashyap S, et al. Anatomy, Abdomen and Pelvis: Anterolateral Abdominal Wall Fascia. [Updated 2022 Oct 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459392/

5. Rozen WM, Ashton MW, Taylor GI. Reviewing the vascular supply of the anterior abdominal wall: redefining anatomy for increasingly refined surgery. Clin Anat. 2008;21(2):89-98. https://doi.org/10.1002/ca.20585
6. Kostov S, Dineva S, Kornovski Y, Slavchev S, Ivanova Y, Yordanov A. Vascular Anatomy and Variations of the Anterior Abdominal Wall - Significance in Abdominal Surgery. Prague Med Rep. 2023;124(2):108-142. https://doi.org/10.14712/23362936.2023.9
7. Park SO, Imanishi N, Chang H. The Anatomic Features and Role of Superficial Inferior Epigastric Vein in Abdominal Flap. Arch Plast Surg. 2022;49(4):482-487. Published 2022 Jul 30. https://doi.org/10.1055/s-0042-1748645
8. Vasquez JM, Demarque AM, Diamond MP. Vascular complications of laparoscopic surgery. J Am Assoc Gynecol Laparosc. 1994;1(2):163-167. https://doi.org/10.1016/s1074-3804(05)80783-2
9. Schaverien M, Saint-Cyr M. Arterial and Venous Anatomies of the Deep Inferior Epigastric Artery Perforator and Superficial Inferior Epigastric Flaps Plastic & Reconstructive Surgery. 2010;125(3):1045-1046. https://doi.org/10.1097/PRS.0b013e3181cb6849
10. van Tonder DJ, Keough N, van Niekerk ML, van Schoor A. Variant Superficial Epigastric Supply to the Anterior Abdominal Wall Arising from Inferior Epigastric Perforators: A Neonatal Case Report. Anatomia. 2026; 5(1):7. https://doi.org/10.3390/anatomia5010007
11. Manolakos K, Zygogiannis K, Manolakos O, Mousa C, Papadimitriou G, Fotoniatas I. Anatomical variations of ilioinguinal nerve: A systematic review of the literature. Surg Neurol Int. 2024;15:225. Published 2024 Jul 5. https://doi.org/10.25259/SNI_232_2024
12. Bowness J, Seeley J, Varsou O, et al. Arterial Anatomy of the Anterior Abdominal Wall: Evidence-Based Safe Sites for Instrumentation Based on Radiological Analysis of 100 Patients. Clin Anat. 2020;33(3):350-354. https://doi.org/10.1002/ca.23463
13. Le Saint-Grant A, Taylor A, Varsou O, Grant C, Cezayirli E, Bowness J. Arterial anatomy of the anterior abdominal wall: Ultrasound evaluation as a real-time guide to percutaneous instrumentation. Clin Anat. 2021;34(1):5-10. https://doi.org/10.1002/ca.23578
14. Meyerov J, Ram R, Grinsell D. Refining the abdominal wall perforasome with clinical application. J Plast Reconstr Aesthet Surg. 2025;105:283-291. https://doi.org/10.1016/j.bjps.2025.04.024

 

Author's contribution statement

Comment 10

I suggest stating more precise roles and exact contribution of each author. I recommend a standardize list such as The CRediT Author Statement [https://www.elsevier.com/researcher/author/policies-and-guidelines/credit-author-statement].

Response:

The authors has changed the authors contribution statement to a formalized CRediT (Contributor Roles Taxonomy) author statement.

Action taken:

The Author Contributions section has been replaced with the following standardized CRediT statement:

"Daniël J. van Tonder (D.J.v.T): Conceptualization, Methodology, Formal analysis, Investigation, Writing - Original Draft, Visualization. Natalie Keough (N.K): Methodology, Validation, Writing - Review & Editing, Supervision. Martin L. van Niekerk (M.L.v.N): Conceptualization, Clinical contextualization, Validation, Writing - Review & Editing. Albert van Schoor (A.v.S): Conceptu-alization, Resources, Writing - Review & Editing, Project administration, Supervision. All authors approved the final version of this document before submission. Additionally, all the authors agreed to be accountable for all aspects of the work to ensure that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.”

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript entitled “Vasculature of the Anterior Abdominal Wall and Surface Anatomy of the Liver and Stomach: Considerations for Minimal Access Surgeries in Neonates” presents a quantitative anatomical investigation of the superficial and deep vasculature of the neonatal anterior abdominal wall, with the aim of identifying safer sites for laparoscopic port placement. The authors performed dissections on thirty formalin-fixed neonatal cadavers and used a grid-based anatomical approach combined with digital image analysis to measure distances between vascular structures and clinically relevant anatomical landmarks. The topic is clinically relevant, as minimally invasive surgery is increasingly performed in neonates and precise anatomical knowledge is essential to reduce the risk of vascular injury during trocar insertion. Overall, the study addresses an important gap in the literature, since detailed quantitative anatomical data on the neonatal anterior abdominal wall remain limited.

The methodology is generally well described and the use of digital image analysis software to standardize measurements represents a methodological strength. The presentation of results through tables, anatomical grids, and kernel density plots allows the reader to visualize the spatial distribution of vessels in relation to surface landmarks. In addition, the inclusion of data on the surface anatomy of the liver and stomach increases the clinical relevance of the study, as these structures may be at risk during minimally invasive procedures in neonates. The findings suggesting the presence of a relatively less vascular midline corridor are potentially valuable for surgical planning.

Despite these strengths, several issues should be addressed to improve the manuscript. First, the study does not sufficiently discuss the considerable anatomical variability of abdominal wall vessels and nerves. The superior and inferior epigastric arteries, as well as the iliohypogastric and ilioinguinal nerves, are known to demonstrate significant anatomical variation in their course and branching patterns. This variability may influence the reliability of fixed anatomical landmarks for predicting the location of these structures. The current analysis appears to assume relatively consistent vascular pathways, yet the inherent variability of these vessels and nerves is not adequately acknowledged or incorporated into the interpretation of the results. A more detailed discussion of this anatomical variability and its implications for surgical safety would strengthen the clinical applicability of the study.

Second, the use of formalin-fixed cadavers may influence the spatial relationships between anatomical structures due to tissue shrinkage and changes in elasticity. Although cadaveric studies are common in anatomical research, the potential effect of fixation on measured distances should be acknowledged more explicitly as a limitation. Third, the sample size of thirty specimens, while acceptable for an anatomical dissection study, remains relatively limited and may not fully capture the spectrum of anatomical variation present in the neonatal general population. In particular, the sample is largely derived from a single geographic and demographic cohort, which may limit the generalizability of the findings.

Furthermore, although the study presents extensive quantitative measurements, the clinical interpretation of these values could be expanded. The differences between vascular distances in the midline and lateral regions are often only a few millimeters, which may still be clinically relevant in neonatal surgery due to the very small operative field. The discussion would benefit from a clearer explanation of how these measurements translate into practical recommendations for trocar placement. Additionally, the authors should clarify whether all photographs used for image analysis were obtained under standardized conditions, including camera height, angle, and calibration procedures, to ensure measurement consistency.

Minor improvements could also be made in the clarity and organization of the manuscript. The introduction contains some historical background on laparoscopy that could be shortened to focus more directly on neonatal surgical anatomy. The legends of several figures could be expanded to facilitate interpretation of the graphical data, particularly the color-coded kernel density plots. In addition, the terminology describing vascular structures should be used consistently throughout the text.

In summary, the manuscript presents valuable anatomical data that may contribute to improving the safety of minimally invasive procedures in neonates. However, the discussion should more thoroughly address the substantial anatomical variability of key abdominal wall vessels and nerves, including the superior and inferior epigastric arteries and the iliohypogastric and ilioinguinal nerves, as well as the methodological limitations of cadaveric measurements. After addressing these issues and expanding the discussion of clinical implications, the manuscript would represent a useful contribution to the anatomical and surgical literature.

Author Response

The manuscript entitled “Vasculature of the Anterior Abdominal Wall and Surface Anatomy of the Liver and Stomach: Considerations for Minimal Access Surgeries in Neonates” presents a quantitative anatomical investigation of the superficial and deep vasculature of the neonatal anterior abdominal wall, with the aim of identifying safer sites for laparoscopic port placement. The authors performed dissections on thirty formalin-fixed neonatal cadavers and used a grid-based anatomical approach combined with digital image analysis to measure distances between vascular structures and clinically relevant anatomical landmarks. The topic is clinically relevant, as minimally invasive surgery is increasingly performed in neonates and precise anatomical knowledge is essential to reduce the risk of vascular injury during trocar insertion. Overall, the study addresses an important gap in the literature, since detailed quantitative anatomical data on the neonatal anterior abdominal wall remain limited.

 

The methodology is generally well described and the use of digital image analysis software to standardize measurements represents a methodological strength. The presentation of results through tables, anatomical grids, and kernel density plots allows the reader to visualize the spatial distribution of vessels in relation to surface landmarks. In addition, the inclusion of data on the surface anatomy of the liver and stomach increases the clinical relevance of the study, as these structures may be at risk during minimally invasive procedures in neonates. The findings suggesting the presence of a relatively less vascular midline corridor are potentially valuable for surgical planning.

 

Despite these strengths, several issues should be addressed to improve the manuscript.

Response:

We thank the reviewer for his time and dedication to the peer review process. The reviewers' comments have most definitely aided in strengthening the scientific rigor of this manuscript.

 

Comment 1

First, the study does not sufficiently discuss the considerable anatomical variability of abdominal wall vessels and nerves. The superior and inferior epigastric arteries, as well as the iliohypogastric and ilioinguinal nerves, are known to demonstrate significant anatomical variation in their course and branching patterns. This variability may influence the reliability of fixed anatomical landmarks for predicting the location of these structures. The current analysis appears to assume relatively consistent vascular pathways, yet the inherent variability of these vessels and nerves is not adequately acknowledged or incorporated into the interpretation of the results. A more detailed discussion of this anatomical variability and its implications for surgical safety would strengthen the clinical applicability of the study.

Response:

The authors agree that the anterior abdominal wall demonstrates considerable anatomical variability, particularly in the course and branching patterns of the superior and inferior epigastric arteries, as well as in the trajectory of the iliohypogastric and ilioinguinal nerves. To address this, a dedicated paragraph has been added to the Discussion explicitly acknowledging this variability and emphasising that the anatomical relationships described in this study should be interpreted as probabilistic rather than absolute. The clinical implications of this variability have also been incorporated, reinforcing the recommendation for direct visualisation during port placement, particularly in lateral abdominal regions where vascular density is greatest. We believe this addition strengthens the clinical applicability and interpretative balance of the manuscript.

Action taken:

Discussion has been updated

 

Comment 2

Second, the use of formalin-fixed cadavers may influence the spatial relationships between anatomical structures due to tissue shrinkage and changes in elasticity. Although cadaveric studies are common in anatomical research, the potential effect of fixation on measured distances should be acknowledged more explicitly as a limitation. Third, the sample size of thirty specimens, while acceptable for an anatomical dissection study, remains relatively limited and may not fully capture the spectrum of anatomical variation present in the neonatal general population. In particular, the sample is largely derived from a single geographic and demographic cohort, which may limit the generalizability of the findings.

Response:

The reviewer highlights limitations in the use of Formalin fixation body donations as pertaining to tissue shrinkage. The literature indicates that formalin submersion and subsequent fixation processes can result in a tissue shrinkage factor ranging from 11.4% to 15.1%. Consequently, a vascular distance measured at 6.84 mm in a fixed cadaver might correspond to nearly 8 mm in a fresh, unfixed state. Additionally, the cohort is highly homogenous (86.7% Black South African). The authors have tried to address these limitations, together with suggestions highlighted by Reviewer 1, and we hope the changes to the “limitations” section are satisfactory.

Action taken:

The Limitations of the study section have been refined.

 

Comment 3

Furthermore, although the study presents extensive quantitative measurements, the clinical interpretation of these values could be expanded. The differences between vascular distances in the midline and lateral regions are often only a few millimeters, which may still be clinically relevant in neonatal surgery due to the very small operative field. The discussion would benefit from a clearer explanation of how these measurements translate into practical recommendations for trocar placement. Additionally, the authors should clarify whether all photographs used for image analysis were obtained under standardized conditions, including camera height, angle, and calibration procedures, to ensure measurement consistency.

Response:

The discussion has been expanded to address the synergistic comments with Reviewer 1, Comment 4. Regarding image standardization, strict parameters were maintained throughout the data collection phase, which has now been explicitly documented in the methods, as also mentioned by Reviewer 1 (Comment 7).

Action taken:

Expanded discussion as detailed in the action taken for Reviewer 1, Comments 4 and 7, along with the Materials and Methods section, was updated.

 

Comment 4

Minor improvements could also be made in the clarity and organization of the manuscript. The introduction contains some historical background on laparoscopy that could be shortened to focus more directly on neonatal surgical anatomy. The legends of several figures could be expanded to facilitate interpretation of the graphical data, particularly the color-coded kernel density plots. In addition, the terminology describing vascular structures should be used consistently throughout the text.

Response:

The authors agree that the historical exposition could be removed from the lengthy manuscript. The introduction has been trimmed of historical laparoscopy references and refocused on anatomy (as noted in response to Reviewer 2, Comment 1). The legend for the kernel density plots (The superficial and deep, Figure 4 and Figure 5 have been combined) has been expanded to explain the standardized distribution curves. Finally, a complete review of the manuscript was performed to ensure standard terminology throughout (e.g., exclusively utilizing "inferior epigastric artery" rather than alternating irregularly with "deep epigastric").

Action taken:

Historical laparoscopy references in the Introduction were deleted.

Figure legends for the density plots (now Figure 3) have been expanded.

Vascular nomenclature was standardized throughout the text.

 

Summary Comment

In summary, the manuscript presents valuable anatomical data that may contribute to improving the safety of minimally invasive procedures in neonates. However, the discussion should more thoroughly address the substantial anatomical variability of key abdominal wall vessels and nerves, including the superior and inferior epigastric arteries and the iliohypogastric and ilioinguinal nerves, as well as the methodological limitations of cadaveric measurements. After addressing these issues and expanding the discussion of clinical implications, the manuscript would represent a useful contribution to the anatomical and surgical literature.

Response:

The authors thank the reviewer for their thoughtful summary and constructive feedback. The concerns regarding anatomical variability and its implications for clinical applicability have been addressed through the addition of a dedicated paragraph in the Discussion (as detailed in Response to Comment 1), where the variability of the anterior abdominal wall vasculature and associated neural structures is acknowledged and integrated into the interpretation of the findings. We believe these revisions have strengthened the clinical relevance and overall balance of the manuscript.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The revised manuscript has improved substantially in response to the previous round of review, and I would like to commend the authors for the careful and constructive manner in which they have addressed the majority of the concerns raised. The clarification of the study population, the more cautious interpretation of generalizability, and the refinement of the central conclusions, particularly the shift from “avascular” to “reduced vascular” terminology, have significantly strengthened the scientific rigor and credibility of the work. The addition of a summary table to enhance clinical readability is also a valuable improvement, and the revisions to the Discussion have resulted in a clearer and more focused narrative.

There are, however, a few remaining points that would benefit from minor clarification before the manuscript is finalized. First, regarding the handling of outliers, the revised text explains the rationale for excluding measurements beyond ±3 Z-scores; however, it would improve transparency to briefly report how many data points were excluded and, if possible, from which anatomical regions. Even a short statement indicating that the number of excluded observations was small and did not materially affect the overall trends would help reassure the reader that the results are robust and not sensitive to data filtering decisions.

Second, the explanation of the unit of analysis and the descriptive nature of the statistical approach is now much clearer and acceptable. Nonetheless, a brief additional sentence explicitly acknowledging that pooled measurements may slightly overrepresent specimens contributing more data points would further strengthen methodological transparency, even if this does not alter the descriptive conclusions.

Third, the section discussing the neonatal adaptation of Palmer’s point is now more appropriately framed as hypothesis-generating, which is a significant improvement. That said, I would still encourage the authors to slightly soften the presentation of specific numerical thresholds (e.g., distances in millimeters or centimeters) to avoid the impression of direct procedural applicability. A brief reminder that these values represent anatomical estimates under cadaveric, non-distended conditions, and should not be interpreted as precise intraoperative guidelines, would further align the discussion with the study design.

Finally, the expanded inter-observer analysis is appreciated and adds useful detail. However, the interpretation of measurement differences as “not clinically significant” could be expressed with slightly more nuance. Given that some measured anatomical distances are very small, even modest discrepancies may represent a meaningful proportion of the available safety margin. A short contextual sentence linking measurement variability to typical instrument dimensions (such as trocar diameter) would help readers better appreciate the clinical relevance of these differences.

Overall, this is a well-conducted and thoughtfully revised anatomical study that provides meaningful insight into a clinically important problem. The remaining points are relatively minor and primarily relate to clarity and framing rather than fundamental methodological concerns. With these final adjustments, the manuscript will be well-positioned to make a valuable contribution to the literature.

Comments on the Quality of English Language

The English language has improved noticeably following revision, and the manuscript is now generally clear and readable. Terminology is more consistent, and sentence structure has been simplified in several key sections, particularly in the Discussion. Only minor stylistic refinements may still be considered, mainly to further enhance conciseness and flow, but no substantial language editing is required at this stage.

Author Response

Reviewer 1

The revised manuscript has improved substantially in response to the previous round of review, and I would like to commend the authors for the careful and constructive manner in which they have addressed the majority of the concerns raised. The clarification of the study population, the more cautious interpretation of generalizability, and the refinement of the central conclusions, particularly the shift from “avascular” to “reduced vascular” terminology, have significantly strengthened the scientific rigor and credibility of the work. The addition of a summary table to enhance clinical readability is also a valuable improvement, and the revisions to the Discussion have resulted in a clearer and more focused narrative.

There are, however, a few remaining points that would benefit from minor clarification before the manuscript is finalized.

 

Response:

The authors thank the reviewer for his positive comments and appreciate that their dedication to addressing the concerns has been recognized.

 

Comment 1

First, regarding the handling of outliers, the revised text explains the rationale for excluding measurements beyond ±3 Z-scores; however, it would improve transparency to briefly report how many data points were excluded and, if possible, from which anatomical regions. Even a short statement indicating that the number of excluded observations was small and did not materially affect the overall trends would help reassure the reader that the results are robust and not sensitive to data filtering decisions.

 

Response:

The application of a strict ±3 Z-score threshold was utilized strategically to prevent extreme biological outliers from skewing the mean distance calculations. However, as the reviewer points out (as does Reviewer 4, Comment 1), failing to quantify the exact number of excluded data points obscures the true extent of anatomical variability and reduces methodological transparency. An exhaustive retrospective analysis of the filtered dataset confirms that a minimal number of data points were excluded from the final central tendency calculations. A brief statement has been added to the statistical methods and results sections to transparently report these specific exclusions, ensuring readers and clinicians can inherently trust that the robustness of the central tendencies was not artificially manufactured through aggressive data filtering decisions.

 

Action taken:

The following text has been added directly to the "Statistical analyses" section:

To reduce recording mistakes and extreme biological measurements impacting the mean and standard deviation, a total of 48 directional measurements, representing less than 0.01% (n = 5606) of the total comprehensive dataset, yielded Z-scores that were greater than 3 or less than -3 and were removed from the dataset.

 

Comment 2

Second, the explanation of the unit of analysis and the descriptive nature of the statistical approach is now much clearer and acceptable. Nonetheless, a brief additional sentence explicitly acknowledging that pooled measurements may slightly overrepresent specimens contributing more data points would further strengthen methodological transparency, even if this does not alter the descriptive conclusions.

 

Response:

This descriptive spatial approach maps the frequency of vascular encounters across the defined geometric grid. Recognizing the potential for clustering within specimens improves the transparency of the theoretical model. It highlights that the probability densities are not based on entirely independent biological events but rather arise from a combined topographical landscape.

 

Action taken:

The following detailed text has been appended to the "Statistical analyses" section to transparently address the nuances of pooling spatial data and intra-class correlation:

"This anatomical framework allows for the description of vascular density across the abdominal wall. However, pooling measurements from different directions within a single specimen introduces some statistical dependence. This means that neonatal specimens with complex or dense vascular branching may slightly skew the average measurements in certain local quadrants. Nonetheless, this clustering is a natural consequence of topographical mapping and does not compromise the overall conclusions.”

 

Comment 3

Third, the section discussing the neonatal adaptation of Palmer’s point is now more appropriately framed as hypothesis-generating, which is a significant improvement. That said, I would still encourage the authors to slightly soften the presentation of specific numerical thresholds (e.g., distances in millimeters or centimeters) to avoid the impression of direct procedural applicability. A brief reminder that these values represent anatomical estimates under cadaveric, non-distended conditions, and should not be interpreted as precise intraoperative guidelines, would further align the discussion with the study design.

 

Response:

While the calculated morphometric thresholds offer a theoretical safe zone for avoiding these viscera. However, the authors agree with the reviewer that presenting them as absolute, numeric targets could be considered hazardous, considering the lack of pneumoperitoneum in formalin-fixed cadaveric donations. In vivo insufflation (typically maintained at 8-10 mmHg in neonates) dramatically stretches the parietal peritoneum and lifts the anterior abdominal wall away from the viscera, fundamentally changing the trajectory, depth, and safety margins of a blind Veress needle insertion. The text has been softened to ensure these specific distance measurements are interpreted as structural baselines rather than direct procedural directives.

 

Action taken:

The "Discussion" section has been modified. The revised text now reads:

"As such, the neonatal equivalent of Palmer's point, from the anatomical finding from this sample, suggests a blind Veress needle insertion, where the liver and stomach would not be in danger, would be significantly below the costal margin in the left midclavicular line, considering the upper limit of the 95% CI for the stomach. "

 

Comment 4

Finally, the expanded inter-observer analysis is appreciated and adds useful detail. However, the interpretation of measurement differences as “not clinically significant” could be expressed with slightly more nuance. Given that some measured anatomical distances are very small, even modest discrepancies may represent a meaningful proportion of the available safety margin. A short contextual sentence linking measurement variability to typical instrument dimensions (such as trocar diameter) would help readers better appreciate the clinical relevance of these differences.

 

Response:

In adult laparoscopic surgery, an inter-observer measurement bias of 1.16 mm might be readily dismissed as negligible noise. However, in the severely congested neonatal abdomen, where the minimal circumferential distance to a deep vascular structure at an intersection like point 'p' (located at the left midclavicular line in the lower quadrant) is only 1.16 ± 1.27 mm, an identical measurement bias of 1.16 mm represents a 100% margin of error. Standard neonatal laparoscopic instrumentation utilizes fine 3 mm and 5 mm trocars. A spatial discrepancy of over 1 mm constitutes more than one-third of a 3 mm trocar's entire diameter. The manuscript has been revised to excise the dismissive "not clinically significant" phrasing. It has been replaced with a nuanced, contextualized evaluation.

 

Action taken:

The "Inter-observer and intra-observer error analysis" section has been revised.

 

Summary Comment

Overall, this is a well-conducted and thoughtfully revised anatomical study that provides meaningful insight into a clinically important problem. The remaining points are relatively minor and primarily relate to clarity and framing rather than fundamental methodological concerns. With these final adjustments, the manuscript will be well-positioned to make a valuable contribution to the literature.

 

Response:

We sincerely appreciate the reviewer's closing remarks. The reassurance and validation for the hard work put into the research are truly valued.

 

Comments on the Quality of English Language

The English language has improved noticeably following revision, and the manuscript is now generally clear and readable. Terminology is more consistent, and sentence structure has been simplified in several key sections, particularly in the Discussion. Only minor stylistic refinements may still be considered, mainly to further enhance conciseness and flow, but no substantial language editing is required at this stage.

Response:

The acknowledgment of the improved linguistic clarity is appreciated.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The article presentation had been improved and all essential changes had been sufficiently made. 

Author Response

Reviewer 3

The article presentation had been improved and all essential changes had been sufficiently made.

 

Response:

We appreciate the reviewer for their positive feedback and detailed suggestions during the initial revision round, which greatly enhanced the manuscript's overall quality.

No action taken.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript presents a valuable and clinically relevant anatomical analysis of the neonatal anterior abdominal wall, addressing an important and underexplored topic in the context of minimally invasive surgery. The study is well-conceived, based on a relatively robust cadaveric sample for this population, and employs a structured anatomical grid that allows for systematic and reproducible measurements. The combination of detailed dissection, image-based analysis, and efforts to assess measurement reliability (including Bland–Altman evaluation) represent clear methodological strengths. The dataset is rich, and the findings—particularly regarding the relative safety of the midline and the increased vascular density in lateral regions—are potentially useful for guiding surgical practice. Overall, the manuscript is publishable and constitutes a meaningful contribution to the field.

At the same time, several aspects of the methodology and interpretation would benefit from further refinement to strengthen the scientific rigor and clinical applicability of the study.

The approach to outlier handling requires clarification and reconsideration. The exclusion of measurements based on Z-scores exceeding ±3, while statistically common, is potentially problematic in anatomical research, where extreme values may represent true anatomical variation rather than measurement error. Given that rare variants can be clinically important—especially in a neonatal surgical context—it would be important for the authors to specify how many data points were excluded and to justify this decision more explicitly. Ideally, extreme values should be reported or at least discussed, rather than removed without detailed contextualization.

The use of kernel density plots as a primary tool for interpreting spatial distribution, although visually informative, carries a risk of overinterpretation. Kernel density estimation is sensitive to smoothing parameters and does not directly translate into clinically meaningful probabilities or risk thresholds. The current presentation may give an impression of precision that is not fully supported by the underlying data structure. The manuscript would benefit from complementing these plots with more interpretable statistical descriptors, such as percentile-based distances (e.g., 5th or 10th percentile) or a clearer explanation of how these distributions should inform surgical decision-making.

The analytical framework assumes independence of observations, although multiple measurements were obtained from each specimen. This introduces a potential issue of non-independence (clustering), which is not formally accounted for in the analysis. While this may be acceptable within a descriptive anatomical framework, it should be explicitly acknowledged as a limitation, and its implications for the interpretation of variability should be discussed.

Although the inclusion of Bland–Altman analysis to assess inter- and intra-observer agreement is a methodological strength, it is based on a relatively small subset of the sample (approximately 10%, n = 5). This limited subsample may constrain the robustness of conclusions regarding measurement reliability and should be acknowledged as such.

Some of the interpretative language appears slightly overstated, particularly regarding the concept of an “avascular” midline corridor. While the data do support a relative reduction in vascular density in the midline, the presence of measurable distances and variability suggests that this region is not truly avascular. A more cautious formulation (e.g., “relatively less vascular” or “reduced vascular density”) would better reflect the empirical findings and avoid potential misinterpretation in a clinical setting.

The potential influence of sample heterogeneity is not fully explored. Although the cohort is defined as neonates, there is still variability in age (within the first weeks of life), body size, and weight, which could plausibly affect spatial relationships between anatomical structures. In addition, the sample is dominated by a single population group, which may limit the generalizability of the findings. The absence of any stratified or correlational analysis (e.g., with weight or size) should be acknowledged as a limitation, or briefly explored if the data permit.

The use of formalin-fixed cadaveric material introduces an inherent limitation related to tissue properties and anatomical relationships, which may differ from those observed in vivo. While this is standard in anatomical research, a brief discussion of how fixation might influence spatial measurements and clinical applicability would strengthen the manuscript.

Minor issues of terminology and editorial consistency remain throughout the manuscript. These include occasional inconsistencies in vascular nomenclature (e.g., interchangeable use of “deep epigastric” and “inferior epigastric”), as well as typographical and grammatical errors. A careful language and terminology review would improve clarity and professionalism, particularly given the otherwise high level of the work.

In summary, this is a well-executed and clinically meaningful study that provides novel quantitative insights into neonatal abdominal wall anatomy. The manuscript is suitable for publication; however, several methodological and interpretative aspects would benefit from clarification and more cautious framing. These revisions are relatively minor and primarily involve improving transparency, refining interpretation, and enhancing the connection between quantitative findings and clinical application. Addressing these points will further strengthen the manuscript and increase its value for both anatomists and clinicians.

Author Response

Reviewer 4

The manuscript presents a valuable and clinically relevant anatomical analysis of the neonatal anterior abdominal wall, addressing an important and underexplored topic in the context of minimally invasive surgery. The study is well-conceived, based on a relatively robust cadaveric sample for this population, and employs a structured anatomical grid that allows for systematic and reproducible measurements. The combination of detailed dissection, image-based analysis, and efforts to assess measurement reliability (including Bland–Altman evaluation) represent clear methodological strengths. The dataset is rich, and the findings—particularly regarding the relative safety of the midline and the increased vascular density in lateral regions—are potentially useful for guiding surgical practice. Overall, the manuscript is publishable and constitutes a meaningful contribution to the field.

 

At the same time, several aspects of the methodology and interpretation would benefit from further refinement to strengthen the scientific rigor and clinical applicability of the study.

 

Response:

We appreciate the reviewer's time and effort in the peer review process. Their insights in the second review round have once again helped improve the scientific rigor and overall clarity of the manuscript. The subsequent points raised regarding the nuanced handling of statistical outliers, the potential overinterpretation of spatial density plots, and the physical limitations of formalin-fixed cadaveric material are highly astute. Addressing these specific areas of refinement has added vital layers of clinical and statistical nuance to the manuscript, ensuring the data is interpreted safely and accurately by the community.

 

Comment 1

The approach to outlier handling requires clarification and reconsideration. The exclusion of measurements based on Z-scores exceeding ±3, while statistically common, is potentially problematic in anatomical research, where extreme values may represent true anatomical variation rather than measurement error. Given that rare variants can be clinically important—especially in a neonatal surgical context—it would be important for the authors to specify how many data points were excluded and to justify this decision more explicitly. Ideally, extreme values should be reported or at least discussed, rather than removed without detailed contextualization.

 

Response:

The initial methodological decision to apply a strict ±3 Z-score filter was intended purely to prevent severe biological extremes from mathematically distorting the mean distances. As noted in the response to Reviewer 1 (Comment1), the exact number of excluded points was mathematically minimal, but the clinical necessity to contextualize these specific variants is absolute. The manuscript has been revised to report the exact number of statistical exclusions

 

Action taken:

The following text has been added directly to the "Statistical analyses" section:

To reduce recording mistakes and extreme biological measurements impacting the mean and standard deviation, a total of 48 directional measurements, representing less than 0.01% (n = 5606) of the total comprehensive dataset, yielded Z-scores that were greater than 3 or less than -3 and were removed from the dataset.

 

Comment 2

The use of kernel density plots as a primary tool for interpreting spatial distribution, although visually informative, carries a risk of overinterpretation. Kernel density estimation is sensitive to smoothing parameters and does not directly translate into clinically meaningful probabilities or risk thresholds. The current presentation may give an impression of precision that is not fully supported by the underlying data structure. The manuscript would benefit from complementing these plots with more interpretable statistical descriptors, such as percentile-based distances (e.g., 5th or 10th percentile) or a clearer explanation of how these distributions should inform surgical decision-making.

 

The authors thank the reviewer for this important methodological observation. We agree that kernel density estimation provides a useful visual representation of spatial trends, but may give an impression of precision that is not directly translatable into surgical/clinical decision-making. To address this, percentile-based descriptors (5th and 10th percentiles) have now been incorporated alongside the mean values to provide more conservative and clinically interpretable estimates of minimum distances to vascular structures. These additions allow for a more cautious and practical interpretation of the data, ensuring that the spatial distributions are not overinterpreted as definitive risk thresholds,

 

Action taken:

An additional description was added to line 226 when introducing kernel density plots:

“These density plots should be interpreted as visual representations of spatial trends rather than precise predictors of vascular location or surgical risk.”

 

In addition, percentile-based descriptors (5th and 10th percentiles) have been incorporated and are presented in Table 8. This is to provide more conservative and clinically interpretable estimates of minimum distances to vascular structures. These additions complement the mean-based analysis and allow for a more cautious and clinically relevant interpretation of the data.

 

Comment 3

The analytical framework assumes independence of observations, although multiple measurements were obtained from each specimen. This introduces a potential issue of non-independence (clustering), which is not formally accounted for in the analysis. While this may be acceptable within a descriptive anatomical framework, it should be explicitly acknowledged as a limitation, and its implications for the interpretation of variability should be discussed.

 

Response:

The authors agree with the reviewer that treating these clustered spatial observations as purely independent vectors artificially inflates the perceived statistical degrees of freedom and may underestimate the true standard error of the anatomical variance. The manuscript has an updated transparent acknowledgment of this specific statistical limitation to ensure the descriptive variability is interpreted correctly. A similar concern has been raised by Reviewer 1 (Comment 2). As such, I would suggest looking at the response to the specific comment, in addition to the changes made to the limitation as suggested by this reviewer.

 

Action taken:

In alignment with the statistical modifications made in response to Reviewer 1, the "Limitations of the study" section has been expanded to address the statistical implications of observation clustering:

“Since multiple directional and circumferential measurements were obtained from a geo-metric grid applied to each specimen, the resulting dataset would exhibit intra-class cor-relation, also known as spatial clustering. A single neonatal specimen with a complex, dense, or unusual bilateral vascular branching provides multiple data points that can in-fluence the overall analysis, potentially giving a false impression of localized density var-iations across nearby grid cells. Although pooling data in this way is acceptable for de-scriptive anatomical purposes, the non-independent nature of these data points means that the variances and standard deviations should be viewed as topographical patterns rather than precise biological probabilities.”

 

Comment 4

Although the inclusion of Bland–Altman analysis to assess inter- and intra-observer agreement is a methodological strength, it is based on a relatively small subset of the sample (approximately 10%, n = 5). This limited subsample may constrain the robustness of conclusions regarding measurement reliability and should be acknowledged as such.

 

Response:

The Bland-Altman plot remains the gold standard in biomedical research for assessing the limits of agreement and identifying systematic bias between two quantitative measurement techniques or distinct observers. Evaluating approximately 10% to 15% of a total study population (in this case, n=5 out of N=30) is a commonly accepted practice. With such a severely constrained subset, the standard deviation of the measurement differences is exceptionally sensitive to even a single divergent measurement. This means the true inter-observer variability across the entire 30-specimen cohort could theoretically be either significantly tighter or considerably wider than the subset suggests.

 

Action taken:

The following detailed text has been added directly to the "Inter-observer and intra-observer error analysis" section, specifically acknowledging the statistical limitations of the subsample size:

“It should be noted that this assessment was conducted on a small subset of the overall experimental group (n=5, about 16% of the 30 total specimens). While this subsample is adequate for detecting major systematic biases or significant methodological issues, the limited sample size naturally reduces the statistical power needed to define very precise confidence limits of agreement.”

 

Comment 5

Some of the interpretative language appears slightly overstated, particularly regarding the concept of an “avascular” midline corridor. While the data do support a relative reduction in vascular density in the midline, the presence of measurable distances and variability suggests that this region is not truly avascular. A more cautious formulation (e.g., “relatively less vascular” or “reduced vascular density”) would better reflect the empirical findings and avoid potential misinterpretation in a clinical setting.

 

Response:

A comprehensive, line-by-line review of the entire manuscript has been conducted to eradicate the term "avascular" and replace it with precise, cautious terminology that accurately reflects the relative nature of the surgical risk.

 

Action taken:

A systematic terminological correction was executed throughout the manuscript to eliminate this overstatement. Specific changes include:

1. Abstract: The initial phrasing "A relatively avascular midline corridor was identified" has been permanently altered to "A midline corridor of reduced vascular density was identified."
2. Discussion: The sub-heading and all subsequent text referencing the "avascular midline corridor" have been uniformly replaced with the precise terms "reduced vascular midline corridor" and "zones of relatively less vascularity."
3. Conclusions: All absolute claims regarding the complete absence of vasculature have been carefully softened to accurately reflect the comparative reduction in major vessel density.

 

Comment 6

The potential influence of sample heterogeneity is not fully explored. Although the cohort is defined as neonates, there is still variability in age (within the first weeks of life), body size, and weight, which could plausibly affect spatial relationships between anatomical structures. In addition, the sample is dominated by a single population group, which may limit the generalizability of the findings. The absence of any stratified or correlational analysis (e.g., with weight or size) should be acknowledged as a limitation, or briefly explored if the data permit.

 

Response:

Given the relatively small overall sample size (N=30), attempting to stratify the data into meaningful weight, height, or exact gestational age cohorts for correlational analyses would yield underpowered subgroups, rendering any inferential statistics unreliable and potentially misleading.

 

Action taken:

The "Limitations of the study" section has been expanded:

“The small amount of subcutaneous fat and the notably large liver size significantly alter the distance from the epidermis to deep blood vessels compared to full-term, normal-weight infants. Performing statistically valid stratified correlation analyses based on weight, crown-heel length, or precise gestational age was not feasible, as the resulting subgroups lacked enough power for reliable conclusions. Therefore, the quantitative maps from this study should be used with great caution when applying them to full-term or demographically different neonatal groups.”

 

Comment 7

The use of formalin-fixed cadaveric material introduces an inherent limitation related to tissue properties and anatomical relationships, which may differ from those observed in vivo. While this is standard in anatomical research, a brief discussion of how fixation might influence spatial measurements and clinical applicability would strengthen the manuscript.

Response:

The authors thank the reviewer for this important observation. We agree that the use of formalin-fixed cadaveric material introduces inherent limitations related to altered tissue properties and spatial relationships. To address this, a concise statement has been added to the Limitations section acknowledging that fixation may affect tissue elasticity and dimensional accuracy, and that the absence of pneumoperitoneum differs from in vivo surgical conditions. The implications of these factors for the clinical interpretation of the findings have also been clarified.

 

Action taken:

The Limitations section has been revised to include a concise discussion of the effects of formalin fixation on tissue properties and the absence of pneumoperitoneum, and how these factors may influence the translation of the findings to practice.

 

Comment 8

Minor issues of terminology and editorial consistency remain throughout the manuscript. These include occasional inconsistencies in vascular nomenclature (e.g., interchangeable use of “deep epigastric” and “inferior epigastric”), as well as typographical and grammatical errors. A careful language and terminology review would improve clarity and professionalism, particularly given the otherwise high level of the work.

Response:

The reviewer's attention to nomenclatural precision and editorial consistency is highly valued by the authors.

Action taken:

A document-wide terminological standardization has been applied:

1. All instances of the surgical shorthand "deep epigastric" (e.g., "To avoid injury to the deep epigastric vessels...") have been replaced with the precise Terminologia Anatomica designation: "To avoid injury to the inferior epigastric vessels...".1
2. The term "deep" is now utilized exclusively to differentiate generalized fascial depth layers (e.g., "minimum circumferential distances to deep vascular structures"), ensuring absolutely no confusion remains between specific, named arteries and general topographical planes.
3. A final, intensive proofread by the authors has hopefully rectified all remaining typographical errors.

 

Summary Comment

In summary, this is a well-executed and clinically meaningful study that provides novel quantitative insights into neonatal abdominal wall anatomy. The manuscript is suitable for publication; however, several methodological and interpretative aspects would benefit from clarification and more cautious framing. These revisions are relatively minor and primarily involve improving transparency, refining interpretation, and enhancing the connection between quantitative findings and clinical application. Addressing these points will further strengthen the manuscript and increase its value for both anatomists and clinicians.

Response:

The research team sincerely appreciates the reviewer's highly constructive summary and the authoritative recognition of the manuscript's clinical value.

Author Response File: Author Response.pdf