Dylan C Lippert, MD
Brittany E Howard, MD
Carrlene B Donald, PAC
Thomas H Nagel, MD
Richard E Hayden, MD
Background: Reconstruction of the skull base commonly requires vascularized tissue. There are a variety of reconstructive options including the anterolateral thigh, rectus abdominis, latissimus dorsi and others. Many of these flaps have the significant disadvantage of excess bulk which may require multiple revision procedures to remove adipose tissue. Furthermore, all of these reconstructive options are a poor color match to the facial skin.
The submental flap is a musculocutanous axial pattern flap ideally suited for reconstruction of both anterior and lateral skull base defects. The flap includes bilateral mylohyoid and anterior bellies of digastric musculature providing excellent support of dural reconstructions. The submental flap provides minimal adipose tissue and a potentially large skin paddle that can be harvested from mandibular angle to angle. All of these factors often make a single stage reconstruction possible with the submental flap. Other advantages of the submental flap include the harvest site being in the field, very low donor site morbidity, and superior color match to the facial skin compared to flaps harvested from distant sites. Lastly the submental flap can be transferred as a pedicled flap, a hybrid flap, or a free flap giving the surgeon additional flexibility.
Subjects: Patients (n=18) undergoing reconstruction of anterior and lateral skull base defects with submental flap.
Methods: Data were analyzed for demographics, tumor characteristics, specific reconstructive technique based on the site of the skull base defect, and reconstructive outcome.
Results: Eighteen patients were identified for inclusion. Sixteen patients had lateral skull base defects resulting from resection of malignant lesions. Two patients had anterior skull base defects one resulting from resection of a malignant lesion, the other to cover a defect after debridement of infected hardware. The patients with lateral skull base defects had the submental flap performed as a pedicled flap in 15/16 (94%) cases with sufficient length from the vascular pedicle to reach the defect without tension. Only one submental flap (1/16 6%) used to reconstruct a lateral defect was transferred as a hybrid flap with a free vein anastomosis for increased vascular pedicle length. Both patients (2/2 100%) with anterior skull base defects required the submental flap to be transferred as a free flap.
Within the lateral defect group, 14/15 patients did not require any revision of their reconstruction. There was a single case requiring staged flap revision for elevation and re-inset for a partial auriculectomy reconstruction. One revision procedure was performed for flap contouring in the anterior defect group. The only complication was one hematoma occurring at a donor site. There was 100% flap survival.
Conclusion: The musculocutaneous submental flap provides an excellent option for reconstruction of lateral and anterior skull base defects given its proximity, reliability, ease of harvest, low need for revision procedures, and exceptional color match. The submental flap can be transferred as a pedicled or hybrid flap when reconstructing the lateral skull base, but often requires free tissue transfer techniques when reconstructing the anterior skull base.