Evaluating the Olfactory Fossa Depth and KEROS Classification in Kashmiri Population

Abstract

Background: KEROS classification is a means of classifying the depth of the olfactory fossa The olfactory fossa is shallow depression in the anterior cranial fossa whose floor is formed by medial lamella of cribriform plate located within ethmoid bone, lateral boundary by lateral lamella which is a thin plate like bone and is susceptible to injury during functional endoscopic sinus surgery, especially when fossa is deep/asymmetric. Functional endoscopic sinus surgery (FESS) although considered the gold standard technique to treat various nasal and paranasal sinus disorders but detailed anatomical study of the paranasal sinuses, olfactory fossa and adjacent anatomical structures during surgery is the necessity to avoid the complications like cerebrospinal fluid leak, periorbital and orbital hematoma, and blindness. Computed tomography(CT) is a frequently used imaging method in the evaluation of the paranasal sinuses, nasal cavity and nasopharynx. Objective: The purpose of the study was to evaluate the depth of olfactory fossa and ethmoid bone using computed tomography in kashmiri population and distributing Kashmir people on the basis of KEROS classification. Methods: In this observational study, PNS CT scan images of 396 patients including 234 males and 162 females between the age group of 17 and 75 years were examined in the Department of Radiodiagnosis, GMC Srinagar. Results: The average depth of the total 792 olfactory fossa (OF) examined was 5.05 mm with a standard deviation (SD) calculated of ±1.51. Statistically, no significant difference was found between males and females in mean OF depth (p>0.05). According to KEROS classification in kashmiri population, 192(24.2%) had type I, 518 sides (65.50%) had type II and 82 sides (10.30%) had type III among 792 olfactory fossa.