Fascia Lata Free Flap Anastomosed to the Supratrochlear System for Reconstruction of the Anterior Skull Base: A Feasibility Study

Objectives: To introduce a novel technique for the reconstruction of the anterior skull base using a free vascularized anterolateral thigh fascia lata flap anastomosed to the supratrochlear artery (StA).

Methods: The diameter of the StA was measured in 38 (76 sides) Computed Tomography Angiographies (CTA). Independently, 6 cadaver heads were used to measure the diameter of the supratrochlear system and the model was applied to one of the specimens.

Results: The average diameter of the StA in females was 2.5mm2 and 2.8 mm2 for the right and left sides respectively; for men, it was 3.0-mm2 and 3.2-mm2 respectively. In cadavers, the average left and right StA diameter was of 2.5-mm2. There was no statistical difference when comparing the right and left StA diameters between the CTA from females and males (p < 0.208 and p < 0.492 respectively). There also was no significant statistical difference when comparing the left and right StA between cadavers (p < 0.68). A fascia lata pedicled free flap anastomosed to the StA was used to reconstruct the anterior skull base. The flap was advanced through the nose, and its pedicle was exteriorized through a keyhole osteotomy. A Lynch incision was used to locate and anastomose the flap to the StA.

Conclusion: The StA is a constant vessel with a 2.5-mm2 to 3.0-mm2 diameter in men and women that can be used as a recipient free flap vessel. The free vascularized fascia lata can cover the entire skull base. This is a novel method to reconstruct the anterior skull base when local flaps are not available.

Keywords

superior trochlear system - anterior skull base - anterolateral fascia lata - free flap