Accurate restoration of soft-tissue volume remains challenging in maxillary reconstruction. This study assessed the feasibility of a defect-oriented digital volumetric planning workflow combined with mixed reality (MR)-guided anterolateral thigh flap (ALTF) harvest.

Patients who underwent maxillectomy followed by ALTF reconstruction between November 2023 and January 2025 were retrospectively reviewed. Preoperative CT data were imported into Mimics Medical 21.0 for three-dimensional reconstruction of the maxilla and tumor. Virtual osteotomy and defect simulation were performed to calculate the simulated recipient-defect capacity, designated as V1. Flap dimensions were then designed using V1 and donor-site adipose thickness. MR guidance was used intraoperatively for perforator localization and flap harvest. Intraoperative flap volume was measured by water displacement (V2), and postoperative flap volume was quantified on CT imaging (V3). Secondary outcomes included flap utilization rate, complications, speech intelligibility, patient satisfaction, and University of Washington Quality of Life scores.The three related volumes were compared using the Friedman test, followed by Bonferroni-adjusted pairwise comparisons.

Fifteen patients were included. Mean flap thickness was 10.80 ± 3.49 mm. Median V1, V2, and V3 values were 61.57 mL (interquartile range [IQR], 44.53), 75.00 mL (IQR, 52.00), and 64.26 mL (IQR, 40.65), respectively. The overall difference was significant (Friedman statistic = 17.200, degrees of freedom = 2; P < 0.001). V2 was significantly greater than V1 (adjusted P < 0.001) and V3 (adjusted P  = 0.003), whereas V1 and V3 did not differ significantly (adjusted P  = 1.000). Mean flap utilization rate was 91.13 ± 9.67%. All flaps survived. One patient developed titanium mesh exposure after radiotherapy; no other major complications occurred. Postoperative speech intelligibility and quality-of-life outcomes were generally favorable.

Digital volumetric planning combined with MR-guided ALTF harvest was technically feasible in this preliminary cohort and provided a reference for individualized flap design. The findings should be interpreted as exploratory, and comparative studies with larger samples are needed to determine whether this workflow improves clinical outcomes or reduces tissue trimming.