Endoscopic modified transseptal bi-nostril approach for pituitary tumors. Efficacy of complex preservation of every turbinate and olfaction: A STROBE analysis

Simple and safe resection of the crista galli

A critical procedure in the transcribriform approach is the resection of the crista galli. However, the standard technique for crista galli resection has several disadvantages. We reviewed the cases of patients with olfactory neuroblastomas who underwent an endoscopic endonasal transcribriform approach using a newly developed technique for crista galli resection. We performed a cadaveric study to measure the superior accessibility limits using the proposed method. We included 38 patients with olfactory neuroblastomas in this study. The tumor invaded the posterior crista galli in four patients. The anterior end of the crista galli was not invaded by the tumor. Our cadaveric study showed that the dura was approachable to the point that was 7.4 ± 1.3 mm superior and 23.2 ± 7.2 mm lateral to the foramen cecum following crista galli removal. By resecting the crista galli in advance, manipulation of the superior dura became feasible.

Improved nasal recovery and intact olfactory function after a transseptal approach for endoscopic endonasal transsphenoidal adenomectomy: A retrospective analysis

Objectives

Endoscopic endonasal transsphenoidal adenomectomy (TSA) is the most frequently performed skull base surgery, and researchers have recently focused on preserving nasal function. The endoscopic transseptal approach is a promising procedure due to its reduced injury to the nasal mucosa; however, there are no studies comparing rhinological and neurosurgical outcomes concurrently with the standard endoscopic transnasal approach. Therefore, we conducted this study to investigate whether the transseptal approach could reduce nasal morbidities with comparable neurosurgical outcomes.

Methods

We retrospectively reviewed 25 patients who underwent endoscopic endonasal transseptal TSA for pituitary adenoma without encasement of internal carotid artery from January 2019 to December 2020. Another 25 patients who received transnasal approach from January 2017 to December 2018 were selected as controls. Patients with diseases affecting the nasal cavity/olfaction or usage of a nasoseptal flap were excluded for a better comparison of the two procedures. We collected data from radiological studies, endocrine studies, endoscopic evaluations, 22-item sinonasal outcome tests (SNOT-22) and Top International Biotech Smell Identification Test (TIBSIT) for comparison.

Results

Lower postoperative SNOT-22 and Lund-Kennedy endoscopic scores were observed in the transseptal group. The effect size of differences were classified as large effect (The absolute value of Cohen's d > 0.8). Nevertheless, the TIBSIT scores were not significantly different. The rates of gross total resection, recovery of hormonal abnormalities, and complications were not significantly different. After controlling possible confounding factors using multivariate analysis, the endoscopic transseptal approach remained an independent factor for lower SNOT-22 scores and Lund-Kennedy endoscopic scores.

Conclusions

The endoscopic transseptal approach provides improved recovery of nasal mucosa and intact olfaction without compromising neurosurgical outcomes.

Level of Evidence

2b.