Free tissue transfer for central skull base defect reconstruction: Case series and surgical technique

Free Tissue Transfer for Skull Base Osteoradionecrosis: A Novel Approach in the Endoscopic Era

OBJECTIVES

Osteoradionecrosis (ORN) of the skull base and craniovertebral junction is a challenging complication of radiation therapy (RT). Severe cases often require surgical intervention through a multi-modal approach. With the evolution in endoscopic surgery and advances in skull base reconstruction, there is an increasing role for microvascular free tissue transfer (MFTT). We describe an endoscopic-assisted approach for the management of ORN of the skull base using fascia lata for MFTT.

STUDY DESIGN

Retrospective case series.

METHODS

Between 2017 and 2021, a review of all cases in which fascia lata MFTT was utilized for skull base ORN was performed. Patient demographics, preoperative characteristics, and postoperative outcomes with long-term follow-up were reviewed.

RESULTS

Five patients were identified. Mean duration to onset of ORN was 17 months following RT. A trial of antibiotics, hyperbaric oxygen (HBO), and/or limited debridement was attempted without success. Refractory pain and progressive osteomyelitis were unifying symptoms. All patients underwent endoscopic debridement of the affected region of ORN prior to MFTT. Vascularized fascia lata was inset through a combined endonasal and transoral corridor. There was improvement in chronic pain in the postop setting with no patients requiring continued antibiotics or HBO therapy. Mean post-op follow-up was 23 months.

CONCLUSIONS

With continued evolution in endoscopic, minimally invasive approaches, there is an expanding indication for early surgical management in refractory ORN. Fascia lata MFTT is a novel and effective strategy for the management of ORN of the skull base and upper cervical spine with excellent postoperative outcomes and limited patient morbidity.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:562-568, 2023.

Endoscopic Endonasal Repair of Recurrent Cerebrospinal Fluid Leak With Adipofascial Anterolateral Thigh Free Flap: Case Report and Review of Literature

Background. Cerebrospinal fluid leaks are the most common complication of endoscopic endonasal skull base tumor resection. The workhorse nasoseptal flap or other vascularized intranasal flaps may not be a viable option in patients who have previously undergone surgery or local radiation; in these cases, pericranial flaps may also be unavailable. Free flap reconstruction in patients undergoing endoscopic resection is challenging because of limited exposure. The transmaxillary approach has recently been reported for free flap reconstruction of these defects. This report describes a patient with a pituitary tumor who underwent craniotomy and resection of a pituitary mass via an endoscopic endonasal approach. Postoperatively, the patient developed a high flow cerebrospinal fluid leak that did not resolve with lumbar drain and attempts at endoscopic revision of nasoseptal flap. An adipofascial anterolateral thigh free flap was harvested, based on the descending branch of the lateral circumflex femoral vessels. An upper gingivobuccal sulcus incision was used to access the maxilla. Openings were created in the anterior and medial maxillary sinus to create a passage to the sphenoid sinus. The flap was inset into the defect via this transmaxillary channel. The pedicle was tunneled subcutaneously through the cheek to recipient facial vessels. The procedure resulted in complete resolution of cerebrospinal fluid rhinorrhea and pneumocephalus. Imaging at 18 months showed the flap in good position. This report describes the technique in detail along with a review of the current literature.