(1217) Correlation of Olfactory Neuroepithelium Degeneration Severity in Patients With Olfactory Dysfunction Undergoing Nerve Transfer Surgery

Introduction: An intraoperative olfactory epithelial biopsy is proposed to correlate epithelial damage with outcomes after nerve transfer surgery in patients with olfactory dysfunction.

Methods: In this ongoing prospective study, olfactory neuroepithelial biopsies were obtained from 10 patients undergoing nerve transfer surgery for persistent olfactory dysfunction. Histological damage was assessed by light microscopy and classified according to the scale proposed by Yamagishi et al (1988). Patients were assigned to 2 groups, with half receiving adjunctive postoperative olfactory training. Participants were followed for 2 years, and olfactory outcomes were assessed using the Connecticut Chemosensory Clinical Research Center (CCCRC) test.

Results: Most patients were female, and COVID-19 was the predominant etiology. Duration of olfactory dysfunction before intervention ranged from 20 to 26 months. Histopathological analysis showed predominantly advanced olfactory epithelial degeneration (Yamagishi grade IV), without consistent association with clinical improvement. Postoperative olfactory and visual analog scale outcomes improved variably and were not influenced by adjunctive olfactory training. No statistically significant differences were observed between treatment groups, likely due to the small sample size.

Conclusions: Histopathological assessment of olfactory epithelial degeneration showed no significant differences between groups. No clear association was observed between the degree of epithelial degeneration and treatment response, which may be attributable to the small sample size.