Frequency and Age-Related Changes in Corneal Astigmatism in Cataract Surgery Candidates at a Training Hospital in Turkey
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This is an interesting manuscript, but some recommendations must help improve the quality of this work
1- the introduction is not concise, and the real purpose is not clearly articulated
2- please replace our study by this study throughout the manuscript
3- Please replace our hospital by the name of the institution if desired
4- Our country could be replaced by Turkey
5- the introduction is poorly referenced. Please put a new reference for every significant statement. As it is now, references are not listed in the right format
Methods:
6- Please review lines 80 and 83, and avoid repeating analyzed in the study.
7- Definitions paragraph will need references
8-Line 110: What did authors mean +3 and -3? Standard deviations?
9- Table 1: Please be consistent with the name of the variables. For instance, Mean and Range of age.
Please use Range instead and apply the same logic for the corneal astigmatism variable
10-Figure 4 is difficult to read, please improve the font, and please the key in a better location
11-Figure 2 must show the group comparison, but the placement of the boxes and whiskers does not visually show the statistical significance between groups.
12- Discussion:
This part of the manuscript needs a major improvement.
13- The first paragraph sounds like a part from introduction
14- the real results of this study are not discussed until the last 2 pages
15- the first 2 pages cataract surgery, OCCI, LRI, which could be move to the end of the discussion
16- The discussion looks like a result section. No other papers are discussed, nor their findings contrasted to this study.
17- References missing after every significant statement.
18- line 260 what is wound gape?
19- The findings are not discussed, how the relationship between age and ATR astigmatism could guide surgeons? Please elaborate
20- How middle-aged subjects undergoing cataract surgery should be prepared for toric IOL any differently than what is done today? What are the authors offering based on these findings? What is the clinical applications of these findings?
21-line 350 Please discuss overcorrection in this context
Conclusion: The main findings are not listed in the conclusion
Line 370 to 372 is just an assumption, and should be removed
Author Response
Response to the reviewers
Dear Editor and Reviewers,
We sincerely thank you for your time and for the thoughtful and constructive feedback provided on our manuscript. Your comments have been instrumental in enhancing the overall quality and statistical robustness of the study. We have carefully reviewed and addressed each point raised and revised the manuscript accordingly.
Below, we present our detailed, point-by-point responses to the comments.
In the revised marked version of the manuscript, newly added content is highlighted in yellow, while deleted content is indicated in red. A clean, unmarked version of the revised manuscript has also been uploaded to the system.
Reviewer 1:
This is an interesting manuscript, but some recommendations must help improve the quality of this work.
1- the introduction is not concise, and the real purpose is not clearly articulated.
Thank you for this valuable comment. We have revised the Introduction to improve conciseness and clarity. Redundant explanations were removed, and the structure was streamlined to better focus on the clinical relevance of corneal astigmatism in cataract surgery. Additionally, the aim of the study has been explicitly stated in the final paragraph of the Introduction to clearly articulate the purpose of our work. We believe these revisions have improved the readability and focus of the section.
2-please replace our study by this study throughout the manuscript.
Thank you for the suggestion. We have revised the manuscript and replaced the expression “our study” with “this study” throughout the text to ensure a more formal and consistent academic tone.
3-Please replace our hospital by the name of the institution if desired.
Thank you for the suggestion. We have revised the manuscript and replaced the expression “our hospital” with the full name of the institution throughout the text.
4-Our country could be replaced by Turkey
Thank you for the suggestion. We have revised the manuscript and replaced the expression “our country” with “Turkey” throughout the text.
5-the introduction is poorly referenced. Please put a new reference for every significant statement. As it is now, references are not listed in the right format.
Following your suggestion, reference have been added for each important statement. The introduction section has been completely revised in terms of references and listed in the right format.
Methods:
6-Please review lines 80 and 83, and avoid repeating analyzed in the study.
Thank you for pointing this out. We have revised lines 80 and 83 to eliminate the repeated phrase “analyzed in the study” and improved the wording for clarity and readability.
7-Definitions paragraph will need references.
Thank you for this comment. We have revised the Definitions paragraph and joined the sentences which are referred together by one citation, in accordance with previously published and widely accepted literature.
8-Line 110: What did authors mean +3 and -3? Standard deviations?
We thank the reviewer for this important comment. The values of +3 and −3 refer to the acceptable range for skewness and kurtosis statistics when assessing normality, not to standard deviations. We have revised the sentence to clarify this point and explicitly stated that these thresholds apply to skewness and kurtosis values.
9-Table 1: Please be consistent with the name of the variables. For instance, Mean and Range of age. Please use Range instead and apply the same logic for the corneal astigmatism variable.
Thank you for this comment. We have revised Table 1 to ensure consistent terminology and formatting of variable names. Specifically, the presentation of age has been standardized, and similar adjustments were made for other variables where applicable.
10-Figure 4 is difficult to read, please improve the font, and please the key in a better location.
Figure 4 has been revised in line with your suggestion. Since Figure 2 was removed from the article, Figure 4 is now designated as Figure 3.
11-Figure 2 must show the group comparison, but the placement of the boxes and whiskers does not visually show the statistical significance between groups.
To avoid confusion, Figure 2 has been removed from the article. The results regarding corneal astigmatism by age group were already explained in the main text.
Discussion:
12-This part of the manuscript needs a major improvement.
We thank the reviewer for this important comment. We agree that the Discussion required major improvement. Accordingly, the Discussion section has been substantially revised and reorganized. Result-like descriptions were reduced, the findings were interpreted in the context of relevant literature, and the clinical implications—particularly regarding age-related changes in corneal astigmatism and their relevance for surgical planning—were clearly elaborated. The revised Discussion now focuses on interpretation, comparison with previous studies, and clinical relevance rather than repetition of results.
13- The first paragraph sounds like a part from introduction.
We thank the reviewer for this insightful comment. The Discussion section has been revised to reduce introductory statements and to focus more on the interpretation of our findings and their clinical implications. The first paragraph was rewritten to emphasize the relevance of the results in the context of existing literature rather than restating background information.
14- the real results of this study are not discussed until the last 2 pages.
We thank the reviewer for this important observation. The Discussion section has been substantially revised and reorganized to emphasize the key results of the study. The revised Discussion now follows a result-focused interpretation and comparison with existing literature. We believe this restructuring improves clarity and ensures that the study’s results are appropriately highlighted throughout the Discussion.
15- the first 2 pages cataract surgery, OCCI, LRI, which could be move to the end of the discussion.
We agree with the reviewer. Descriptions of cataract surgery techniques, including clear corneal incisions and other astigmatism correction methods, were moved to later parts of the Discussion to improve flow and to ensure that the section primarily focuses on interpretation of the study findings.
16- The discussion looks like a result section. No other papers are discussed, nor their findings contrasted to this study.
We agree with this comment. The Discussion section has been substantially revised to reduce result-like descriptions. The findings are now interpreted in the context of previously published studies, with direct comparisons made regarding astigmatism magnitude, axis distribution, age-related changes, and vector analysis results across different populations and geographic regions.
17- References missing after every significant statement.
We thank the reviewer for this important observation. We agree that several significant statements required additional referencing. Accordingly, the manuscript has been carefully reviewed, and appropriate references have been added after all major claims and interpretative statements, particularly in the Introduction and Discussion sections. These additions ensure that all statements are adequately supported by the existing literature.
18- line 260 what is wound gape?
Thank you for pointing this out. What we had originally meant by the term “wound gape” was incomplete closure (gaping) of the surgical incision, however we now completely removed that paragraph to reconstruct the Discussion section, thereby improving clarity for the reader.
19- The findings are not discussed, how the relationship between age and ATR astigmatism could guide surgeons? Please elaborate.
We thank the reviewer for this important suggestion. The revised Discussion now elaborates on how the observed age-related increase in ATR astigmatism may influence preoperative planning and long-term refractive expectations in cataract surgery, emphasizing the dynamic nature of corneal astigmatism and the need for individualized surgical decision-making.
20- How middle-aged subjects undergoing cataract surgery should be prepared for toric IOL any differently than what is done today? What are the authors offering based on these findings? What is the clinical applications of these findings?
We agree with the reviewer and have clarified the clinical relevance of our findings. Rather than proposing a specific correction algorithm, the revised Discussion highlights how awareness of age-related astigmatic shifts—particularly the progression toward ATR astigmatism—may help surgeons anticipate long-term refractive changes, optimize patient counseling, and tailor astigmatism management strategies in patients with longer life expectancy.
21-line 350 Please discuss overcorrection in this context.
Thank you for this valuable comment. We have revised the Limitations section to explicitly discuss the issue of overcorrection in the context of age-related astigmatic changes and posterior corneal astigmatism. The revised text now addresses the potential clinical consequences of overcorrection, particularly in with-the-rule astigmatism, and emphasizes its relevance for long-term refractive outcomes and surgical planning.
Conclusion: The main findings are not listed in the conclusion.
We thank the reviewer for this valuable comment. We agree that the initial Conclusion section did not explicitly summarize the main findings of the study. Accordingly, the Conclusion has been revised to clearly and concisely list the key results, including the nonlinear age-related pattern of corneal astigmatism magnitude, the age-dependent shift from WTR to ATR astigmatism, and the significant associations observed in the ATR subgroup. The revised Conclusion now directly reflects the study results without introducing assumptions or interpretations beyond the presented data.
Line 370 to 372 is just an assumption, and should be removed.
We agree with the reviewer. The assumption-related statement has been removed from the Conclusion section, and the text has been revised to reflect only the direct findings of the study and their clinical relevance.
Reviewer 2 Report
Comments and Suggestions for Authors
The authors attempted to evaluate the magnitude, axis, and age-related changes of corneal astigmatism in patients before cataract surgery. However, several questions remain to be answered and discussed in the manuscript.
There appears to be a lack of novelty regarding this study, despite it being one of the limited number of studies reported from Turkey. The authors could compare their data with the data from other countries. It was one of their weak points that they did not have a control group.
If the author compared the post-cataract surgery changes of corneal astigmatism with astigmatism-correcting managements, including on-axis phacoemulsification, OCCI, LRI, femtosecond laser keratotomy, or toric IOL, this study could be persuasive.
Because the author did not use the IOLmaster 700, they did not check the effect of posterior corneal astigmatism; they would have better used the most updated machine.
Author Response
Response to the reviewers
Dear Editor and Reviewers,
We sincerely thank you for your time and for the thoughtful and constructive feedback provided on our manuscript. Your comments have been instrumental in enhancing the overall quality and statistical robustness of the study. We have carefully reviewed and addressed each point raised and revised the manuscript accordingly.
Below, we present our detailed, point-by-point responses to the comments.
In the revised marked version of the manuscript, newly added content is highlighted in yellow, while deleted content is indicated in red. A clean, unmarked version of the revised manuscript has also been uploaded to the system.
Reviewer 2:
The authors attempted to evaluate the magnitude, axis, and age-related changes of corneal astigmatism in patients before cataract surgery. However, several questions remain to be answered and discussed in the manuscript.
There appears to be a lack of novelty regarding this study, despite it being one of the limited number of studies reported from Turkey. The authors could compare their data with the data from other countries. It was one of their weak points that they did not have a control group.
We thank the reviewer for this important comment. We agree that the novelty of the present study does not lie in introducing a new technique or intervention. Instead, its contribution is based on the identification of a nonlinear, U-shaped association between age and corneal astigmatism magnitude, as well as the detailed characterization of age-related shifts toward against-the-rule astigmatism in a large cohort of cataract surgery candidates. Unlike many previous reports describing a linear relationship, our findings highlight the dynamic nature of corneal astigmatism across different age groups. This aspect has been explicitly emphasized in the revised Discussion section.
We acknowledge that the novelty of this study does not lie in introducing a new measurement technique or intervention. Rather, its contribution is based on providing large-scale, contemporary data on corneal astigmatism characteristics and age-related changes from a population that is underrepresented in the literature.
To address this point, the aim of the study has been clarified and expanded in the final paragraph of the Introduction. In addition to describing the frequency, magnitude, type, and age-related distribution of corneal astigmatism, we now explicitly state that the findings are discussed in the context of previously published data from different countries, with a specific focus on geographic comparisons and age-related patterns. This revision highlights the comparative and contextual contribution of the present study.
In response to the reviewer’s suggestion, the Discussion has been revised to include a more explicit comparison of our findings with data reported from different countries and populations. Differences and similarities in astigmatism magnitude, axis distribution, and age-related trends are now discussed in the context of geographic, demographic, and methodological variations, thereby strengthening the comparative and interpretative value of the study.
Regarding the absence of a control group, we agree that the absence of a control group is a limitation. However, given the descriptive and epidemiological design of the study, our primary objective was to characterize corneal astigmatism patterns and age-related changes specifically in cataract surgery candidates rather than to perform a comparative outcome analysis. This point has now been explicitly clarified and acknowledged in the Limitations section of the revised manuscript, and the need for future prospective and controlled studies has been emphasized.
We believe that, with these revisions, the manuscript now more clearly conveys its contribution to the existing literature and its relevance for clinical planning and future research.
If the author compared the post-cataract surgery changes of corneal astigmatism with astigmatism-correcting managements, including on-axis phacoemulsification, OCCI, LRI, femtosecond laser keratotomy, or toric IOL, this study could be persuasive.
We thank the reviewer for this valuable and constructive comment. In response, we have substantially revised the Discussion section to proactively address the raised concerns.
First, we have explicitly clarified the reason for the absence of postoperative comparisons within the Discussion. Rather than leaving this as an implicit limitation, we now clearly state that postoperative astigmatic outcomes and direct comparisons with astigmatism-correcting techniques (such as on-axis phacoemulsification, OCCI, LRI, femtosecond laser keratotomy, or toric IOL implantation) were beyond the scope of the present retrospective, preoperative dataset. This clarification was intentionally added to prevent ambiguity and to transparently define the study boundaries.
Second, we strengthened the clinical context and persuasiveness of the Discussion by emphasizing the practical relevance of preoperative, age-related corneal astigmatism patterns. We highlighted how these data may assist cataract surgeons in anticipating which patient subgroups are more likely to benefit from specific astigmatism-correcting strategies and in tailoring individualized surgical planning, even in the absence of postoperative outcome analysis. This revision directly links our findings to real-world surgical decision-making, as suggested by the reviewer.
Finally, at the end of the Limitations section, we explicitly connected the acknowledged limitations to clear and concrete directions for future research. We now state that prospective, controlled studies incorporating postoperative refractive outcomes and direct comparisons between different astigmatism-correcting modalities are warranted to build upon our findings and to further validate their clinical impact.
We believe that these targeted revisions significantly improve the clarity, clinical relevance, and overall strength of the Discussion, in line with the reviewer’s expectations.
Because the author did not use the IOLmaster 700, they did not check the effect of posterior corneal astigmatism; they would have better used the most updated machine.
We thank the reviewer for this important comment. The IOLMaster 500 was used in this study because it was the standard and consistently available device at our institution during the entire study period. Using a single, well-established device ensured measurement consistency across a large cohort and avoided inter-device variability.
Although newer devices (e.g., IOLMaster 700) provide additional parameters, this study was retrospective in design, and IOLMaster 500 was the available device during that period. To address the reviewer’s concern, we have now explicitly acknowledged this point as a limitation in the manuscript and clarified that future studies incorporating newer-generation biometers may further refine these findings.
Round 2
Reviewer 1 Report
Comments and Suggestions for Authors
Normality tests could have been assessed using Shapiro-Wilk or any other statistical test
Author Response
Response to the reviewers
Dear Editor and Reviewers,
We sincerely thank you for your time and for the thoughtful and constructive feedback provided on our manuscript. Your comments have been instrumental in enhancing the overall quality and statistical robustness of the study. We have carefully reviewed and addressed each point raised and revised the manuscript accordingly.
Below, we present our detailed, point-by-point responses to the comments.
In the revised marked version of the manuscript, newly added content is highlighted in yellow, while deleted content is indicated in red. A clean, unmarked version of the revised manuscript has also been uploaded to the system.
Reviewer 1:
Normality tests could have been assessed using Shapiro-Wilk or any other statistical test.
- As you advised, the normality tests of the data were re-evaluated using the Shapiro-Wilk test. As with the skewness and kurtosis tests, it was confirmed that the data did not show a normal distribution. The statistical analysis section has been revised based on these results. Following this revision, reference study number 19 in the statistical analysis section was removed. The references section was also revised accordingly.
Reviewer 2 Report
Comments and Suggestions for Authors
The authors did their best to incorporate the reviewer's comments.
Author Response
Response to the reviewers
Dear Editor and Reviewers,
We sincerely thank you for your time and for the thoughtful and constructive feedback provided on our manuscript. Your comments have been instrumental in enhancing the overall quality and statistical robustness of the study. We have carefully reviewed and addressed each point raised and revised the manuscript accordingly.
Below, we present our detailed, point-by-point responses to the comments.
In the revised marked version of the manuscript, newly added content is highlighted in yellow, while deleted content is indicated in red. A clean, unmarked version of the revised manuscript has also been uploaded to the system.
Reviewer 2:
The authors did their best to incorporate the reviewer's comments.
- Thank you so much for your valuable feedback.
