Endoscopic assisted insetting of free flaps in anterior skull base reconstruction: A preliminary report of five cases

Abstract

IntroductionFree vascularized tissue may provide a robust reconstruction after anterior skull base surgery. We report our technique and outcomes of the endoscopic inset of free flaps in anterior skull base reconstructions.MethodsBetween 2016 and 2018, endoscopic tumor removal and reconstruction of anterior skull base pathology was performed in five patients aged 20–72 years old (four male, one female). The tumors included three neuroblastomas, a carcinoma, an adenoma, and a melanoma. The median size of the defect was 3.7 × 6.6 cm. Transmaxillary access was gained through the upper sulcus and an anterior and medial maxillectomy. The flap inset was facilitated by the endoscope. The donor vessels were tunneled through the sinus and through the cheek to the facial vessels without the use of the endoscope.ResultsIn three cases a vastus lateralis flap was used, in one case an adipofascial ALT flap and in one case an adipofascial radial forearm flap. Separation of intracranial and sinonasal spaces was confirmed by radiological and endoscopic examinations. There was no flap failure and one case with partial necrosis. One of the flaps needed to be trimmed as it obliterated the nasal cavity and in one of the cases the flap was repositioned postoperatively. Two cases had infectious complications. The mean follow‐up of the patients was 13.8 months.ConclusionsEndoscopic assisted inset of a free flap in the anterior skull base was feasible in the five cases we present. A dedicated, multidisciplinary approach is mandatory for surgical innovation like this.

Anterior skull base reconstruction: a contemporary review

“…In a recent case series, Pipkorn et al [58] described the use of a RFFF via a similar transbuccal-anterior antrostomy approach for skull base reconstruction after endoscopic endonasal surgery. The authors advocate for the use of an adipofascial flap without a skin paddle, wide transmaxillary exposure for safe delivery of the flap, and precise defect measurement prior to harvest due to frequent overestimation with endoscopic views [58] . Rodriguez-Lorenzo et al [59] used a similar transmaxillary approach for endoscopic inset of both muscle (i.e., vastus) and adipofascial flaps (i.e., ALT and RFFF) for complex ASB reconstructions in a small case series.…”

Free tissue transfer for skull base reconstruction - a review

“…A Caldwell-Luc maxillotomy and medial maxillectomy are performed, and the flap is passed through this defect to the skull base. The pedicle can be passed out with this same defect and anastomosed to the facial or angular system without opening the neck [31,33] . When neck dissection is performed, a transcervical inset approach can be used.…”

“…The flap can then be anastomosed to traditional cervical vessels such as the facial artery and vein. In either scenario, should the tunnel be too narrow to pass the flap, it may be delivered to the skull base via the mouth and pulled up with endoscopic instruments, with the pedicle passed out the tunnel with a penrose [33] .…”

“…In this technique, a tunnel behind the pharynx is bluntly created until the nasopharyngeal defect is reached. The flap can then be passed behind the defect and secured superiorly with sutures and fibrin glue, creating an "underlay" inset rather than an "overlay", in which case gravity pulls the flap into contact with the nasopharyngeal mucosa rather than pulling them apart [33] .…”

Free flap transfer, a safe and efficient method for reconstruction of composite skull base defects after salvage resection of advanced intra- and extracranial communicating tumors

“…Non-vascularized grafts or locoregional aps are effective in patients treated with limited resection. However, in the case of salvage surgery, composite resection, large three-dimensional defects, or other complex reconstructive problems like perioperative radiation, free ap transfer provides a more robust reconstruction and should be considered the workhorse [4,5]. Free ap transfer has developed as a highly reliable method for repairing large head and neck defects for the past two decades [5, 6, 4, 7-9, 2, 10, 11].…”