Comparison of Clinical Outcomes Between Transcranial and Transmaxillary Free Flap Insets in Anterior Skull Base...

Large, complex defects in the anterior skull base may require microvascular free flaps. This study compares the clinical outcomes of transcranial and transmaxillary microvascular free flap insertion.

A total of 41 adult patients were included in this study. The medical records provided information on patient demographics, defect measurements, flap characteristics, survival, recurrence, and complications of the patients. Computed tomography images were used to measure skull base defect size (mm²). Kaplan-Meier analysis was carried out to analyze survival. Logistic and multiple logistic regression analyses were used to evaluate the interactions between the clinical variables and outcomes.

Twenty-three patients underwent transcranial flap insetting, and 18 underwent flap insetting using the transmaxillary approach. The 2 groups were comparable in terms of sex, age, and comorbidities but differed in tumor type and staging. The reconstructed defect size was larger in the transcranial insetting group (SD 1371.97 versus 991.3 mm²). The vastus lateralis muscle was the primary choice for reconstruction. At 20 months postoperatively, 90% in the transcranial and 78% in the transmaxillary group were recurrence-free. Overall survival at 40 months was 74% in the transcranial group and 88% in the transmaxillary inset group. The complication rate of Clavien-Dindo 3b or higher was 35.7% overall, with 34.7% in the transcranial group and 38.9% in the transmaxillary group.

The transmaxillary flap insetting approach is feasible for tumors with a large sinonasal component, although it has a higher rate of complications, possibly related to the surgical learning curve.