Integration of Photon-Counting CT into the Surgical Workflow of Complex Maxillofacial Reconstruction: A Pilot Feasibility Study

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

This study is a pilot study aimed at maximizing clinical benefit by reducing radiation exposure through photon counting. It is important to conduct preliminary pilot studies before undertaking such research. The crucial point here is whether the pilot study includes a sample relevant to the intended study. In my opinion, this pilot study appears to include cancer and osteonecrosis patients. Therefore, selecting only one type of case might be more beneficial. Another issue is whether a statistical analysis was conducted for the pilot study. Five cases may not be sufficient to represent the intended study group.

In my view, this study is more of a case series than a pilot study.

There is no information available regarding the long-term results of the study. Also, since it's a series of five patients, it would be better to have pre- and post-operative images and radiological examinations of the patients. This would allow clinicians to more easily perceive changes in the cases and observe the benefits of the method.

My suggestion is that if the study is to be published as a case series, the missing clinical findings (preoperative images and radiological examinations, postoperative control images and radiological examinations, images related to the surgery) should be added;
If it is to be a pilot study, the sample should be increased to at least 10, organized into a single patient group, and clinical images should be included.

Best regards.

Author Response

We sincerely thank the reviewer for the careful evaluation and constructive comments. We have revised the manuscript accordingly and address each point in detail below.

Comment 1: The pilot study appears to include cancer and osteonecrosis patients. Selecting only one type of case might be more beneficial.

Response 1: We appreciate this important observation. In the revised manuscript, the study cohort has been restricted to a homogeneous oncologic population. The final cohort includes ten consecutive patients undergoing microvascular reconstruction for malignant disease (SCC and one mucoepidermoid carcinoma). Non-oncologic cases such as osteoradionecrosis were excluded to ensure diagnostic and clinical consistency (Section 2.1; Table 2).

Comment 2: Was statistical analysis conducted? Five cases may not be sufficient to represent the intended study group.

Response 2: We agree that the initial sample size was limited. The cohort has now been expanded to ten consecutive oncologic patients (n = 10), in accordance with the reviewer’s suggestion. A dedicated statistical analysis section (Section 2.7) has been added. Given the pilot feasibility design and limited sample size, statistical evaluation is descriptive (means, ranges, percentages). No inferential testing was performed, and this limitation is explicitly acknowledged in the Discussion.

Comment 3: This study appears more as a case series than a pilot study.

Response 3: The manuscript has been revised to clearly define the study as a prospective pilot feasibility study with predefined primary and secondary endpoints (Section 2.2). These endpoints include: Technical DICOM transfer and compatibility with VSP/CAD-CAM platforms, Adequacy of osseous delineation for margin planning, Reliability of donor-site vascular mapping within a single acquisition, Intraoperative guide fit, Flap survival and resection margin status. This structured endpoint-based design differentiates the study from a descriptive case series and clarifies its feasibility-focused objective.

Comment 4: No long-term results are provided.

Response 4: Long-term follow-up data have now been included (Section 3.4). All patients were followed for a minimum of 12 months (range 12–16 months) with scheduled clinical and imaging surveillance. No local recurrences, flap failures, or donor-site complications were observed during this period.

Comment 5: Pre- and postoperative images and radiological examinations should be added.

Response 5: We thank the reviewer for this suggestion. The primary objective of the present study was to evaluate the technical feasibility and workflow integration of photon-counting CT (PCCT) within a digital reconstructive pathway, rather than to provide a comprehensive surgical outcome analysis. Accordingly, the revised manuscript includes representative imaging figures demonstrating: Metal artifact reduction (Figure 1), Multiplanar tumor assessment (Figure 2), Donor-site vascular mapping (Figure 3), PCCT-based digital workflow integration (Figure 4). Extensive pre- and postoperative clinical photographic documentation was not incorporated, as the study was not designed to evaluate surgical technique, aesthetic outcomes, or functional rehabilitation. We agree that future larger-scale studies may include standardized clinical photographic documentation to correlate radiologic findings with surgical outcomes.

Comment 6: If published as a pilot study, the sample should be increased to at least 10 and organized into a single patient group.

Response 6: The revised manuscript now includes ten consecutive oncologic patients (n = 10) within a homogeneous disease category. The study is clearly positioned as a pilot feasibility investigation, and its exploratory nature is explicitly acknowledged in both the Methods and Discussion sections.

Closing Statement: We sincerely thank the reviewer for the constructive feedback. The revisions have strengthened the methodological clarity, improved cohort homogeneity, expanded follow-up reporting, and enhanced imaging documentation. We believe the manuscript now more clearly reflects its feasibility-focused objective and clinical scope.

Reviewer 2 Report

Comments and Suggestions for Authors

This is an interesting and timely pilot study evaluating the integration of photon-counting CT (PCCT) into virtual surgical planning and microvascular reconstruction of the mandible and maxilla. The topic is relevant for maxillofacial surgeons and radiologists, and the manuscript is generally well structured. The methodology is clearly described and the clinical workflow is presented in a transparent manner.

However, several conceptual and interpretative issues should be addressed.

• With only 5 patients, the manuscript is more appropriately described as a case series or pilot case series rather than a full original research article.
• The conclusions are currently too definitive given that they are based on only five cases. Statements suggesting clinical impact or transformative potential should be toned down.
• Please rephrase conclusions to highlight feasibility and hypothesis-generating value rather than clinical superiority or broad applicability.
• The statement that FFF is the gold standard in mandibular reconstruction is too absolute. In practice, flap choice is often center-dependent and defect-dependent. Please acknowledge that DCIA and scapular flaps are also widely used and may be preferred in certain clinical scenarios.
• ALT, FRFF, and SCIP flaps are described alongside osseous flaps but their role is different. Please clarify that these are primarily soft-tissue flaps, often used with reconstruction plates and sometimes followed by delayed secondary bony reconstruction after oncologic safety and patient survival are ensured, especially in advanced OSCC cases.
• The quality of some PCCT scans—especially those showing lower extremity vasculature—appears suboptimal. In several images, vascular branching is difficult to appreciate.
• Language is generally good; only minor stylistic editing is needed. In figure descriptions and related text, consider replacing the term “hardware” with the more specific term “reconstruction plate (recon plate)”

Author Response

We sincerely thank the reviewer for the positive evaluation of our work and for the insightful conceptual and interpretative comments. We have carefully revised the manuscript to address each point in detail.

Comment 1: With only 5 patients, the manuscript is more appropriately described as a case series rather than a full original research article.

Response 1: We agree with the reviewer’s assessment regarding the limitations of the initial sample size. The cohort has now been expanded to ten consecutive oncologic patients (n = 10). The study is explicitly framed as a prospective pilot feasibility study with predefined primary and secondary endpoints (Sections 2.1 and 2.2). The manuscript no longer presents itself as a comparative or outcome-driven original research study but rather as an exploratory feasibility investigation aimed at evaluating PCCT integration into a digital surgical workflow.

Comment 2: The conclusions are too definitive and should be toned down.

Response 2: The Conclusions section has been revised to remove statements suggesting clinical superiority or transformative impact. The current wording emphasizes feasibility, workflow compatibility, and hypothesis-generating value. It explicitly states that, due to the limited sample size and absence of direct comparative imaging, no conclusions regarding diagnostic superiority can be drawn (Section 5).

Comment 3: Please acknowledge that DCIA and scapular flaps are widely used; FFF as “gold standard” is too absolute.

Response 3: The wording has been revised in both the Introduction and Discussion. The fibula free flap (FFF) is now described as “widely used” rather than as the gold standard. Additionally, alternative osseous flaps such as DCIA and scapular-based flaps are explicitly acknowledged as established reconstructive options in selected clinical scenarios (Sections 1 and 4).

Comment 4: ALT, FRFF, and SCIP flaps are primarily soft-tissue flaps and should be clarified as such.

Response 4: We thank the reviewer for this important clarification. The Discussion now explicitly differentiates between osseous microvascular flaps and soft-tissue flaps. ALT and FRFF are described as soft-tissue options often used with reconstruction plates or in combined approaches, particularly in advanced oncologic cases. SCIP is discussed separately, and its osteocutaneous application is clarified in the context of limited vertical bone requirements (Sections 4).

Comment 5: Lower extremity vascular scans appear suboptimal; vascular branching is difficult to appreciate.

Response 5: A dedicated section on donor-site vascular assessment (Section 3.3) has been added, including representative coronal MIP reconstructions (Figure 3). We acknowledge that complete visualization of all distal arterial branches on static MIP images may be limited by overlapping osseous structures. Full vascular isolation would require bone subtraction processing, which was not available within the current clinical reconstruction software environment. However, real-time multiplanar workstation evaluation provided sufficient visualization of arterial patency and branching patterns for safe surgical decision-making. Importantly, in one patient (Case 4), PCCT angiography identified a clinically relevant posterior tibial artery occlusion that directly altered flap harvest planning. This supports the diagnostic adequacy of vascular assessment within the study’s feasibility framework.

Comment 6: Replace “hardware” with “reconstruction plate (recon plate).”

Response 6: All instances of the term “hardware” have been replaced with the more specific terminology “reconstruction plate” or “patient-specific implant (PSI)” throughout the manuscript.

Comment 7: Minor stylistic editing.

Response 7: The manuscript has undergone careful linguistic revision. Minor stylistic inconsistencies and typographical errors have been corrected to improve clarity and readability.

Closing Statement: We sincerely thank the reviewer for the constructive and scientifically valuable comments. The revisions have strengthened the methodological clarity, improved conceptual positioning, refined the interpretative tone, and enhanced the imaging documentation. We believe the manuscript now more accurately reflects its feasibility-focused scope and clinical context.