Transinfratemporal Fossa Transposition of the Temporalis Muscle Flap for Skull Base Reconstruction after Endoscopic Expanded Nasopharyngectomy: Anatomical Study and Clinical Application

The Temporoparietal Fascia Flap Transposition Technique for Ventral Skull Base Reconstruction: Anatomic Analysis and Surgical Application

BACKGROUND AND OBJECTIVES

The temporoparietal fascia (TPF) flap is an alternative for revision endoscopic skull base reconstruction in the absence of the nasoseptal flap, and we aimed to investigate the anatomy and surgical application of TPF flap transposition in endoscopic endonasal surgery.

METHODS

Six lightly embalmed postmortem human heads and 30 computed tomography angiography imaging scans were used to analyze the anatomic features of the TPF flap transposition technique. Three cases selected from a 512 endoscopic endonasal cases database were presented for the clinical application of the TPF flap.

RESULTS

The TPF flap, composed by the deepest 3 scalp layers (galea aponeurotica, loose areolar connective tissue, and pericranium), can be harvested and then transposed through the infratemporal-maxillary-pterygoid tunnel to the ventral skull base. The superficial temporal artery as its feeding artery, gives frontal and parietal branches with similar diameter (1.5 ± 0.3 mm) at its bifurcation. The typical bifurcation was present in 50 sides (83.3%), with single (frontal) branch in 5 sides (8.3%), single (parietal) branch in 2 sides (3.3%), and multiple branches (>2) in 3 sides (5%). The transposed TPF flap was divided into 3 parts according to its anatomic location: (1) infratemporal part with an area of 19.5 ± 2.5 cm2, (2) maxillary part with an area of 23.7 ± 2.8 cm2, and (3) skull base part with an area of 44.2 ± 4 cm2. Compared with the nasoseptal flap, nasal floor flap, inferior turbinate flap, and extended septal flap, the coverage area of the skull base part of the TPF flap was significantly larger than any of them (P < .0001).

CONCLUSION

The TPF flap technique is an effective alternative for endoscopic endonasal skull base reconstruction. The TPF flap could successfully cover large skull base defects through the infratemporal-maxillary-pterygoid tunnel.

Salvage endoscopic surgery for skull base osteoradionecrosis in nasopharyngeal carcinoma patients: A prospective, observational, single-arm clinical study

BACKGROUND

Postradiation skull base osteoradionecrosis (ORN) is a severe complication that occurs after radiotherapy in patients with nasopharyngeal carcinoma (NPC) that can severely affect quality of life (QOL) and be life threatening. Only 13.4% - 28.6% of patients can be cured by traditional repeated endoscopic debridement. Here, we introduced salvage endoscopic surgery for skull base ORN patients and evaluated its clinical efficacy.

METHODS

This was a prospective, observational, single-arm clinical study. Clinical data from 18 skull base ORN patients who underwent radical endoscopic necrectomy followed by reconstruction using a septal pedicled mucosal flap or temporal muscle flap were included in the study. The endpoint was an overall survival (OS) of 2 years. The numeric rating scale (NRS) scores for pain and foul odor were analyzed to determine the efficacy and safety of this surgery.

RESULTS

A total of 21 patients were recruited, 18 of whom completed the study and were analyzed. All surgeries were successfully performed. During the 2-year study, the OS rate of the entire cohort was 75%. The median NRS score for pain decreased from 6.44 +- 2.62 to 0.50 +- 0.71, and the NRS score for foul odor decreased from 1.89±1.08 to 1 after surgery.

CONCLUSIONS

Salvage endoscopic necrectomy followed by construction using a septal pedicled mucosal flap or temporal muscle flap is a novel, safe, and effective treatment for ORN in patients with NPC.

CLINICAL TRIAL REGISTRATION

This study was approved by the independent ethics committee of the Eye, Ear, Nose and Throat Hospital of Fudan University (IEC No. 2019095-1). Written informed consent was obtained from all patients. The study was registered with the Chinese Clinical Trial registry (ChiCTR2000029327).