Evaluation of Olfactory Fossa Keros Classification Using CT scans, A Hospital-Based Study

Abstract

Background and objectives: Prior to any surgery for sinonasal diseases, a preliminary scanning of the paranasal sinus is required to validate that the surgical approach is satisfactorily planned and to avoid complications connected to the anatomy of this area. We intended to assess the olfactory fossa depth using paranasal sinus CT images to identify the types and prevalence of Keros classification in our population. Methods: From December 2021 to December 2022, cross-sectional research was carried out at the Department of Radiology of Erbil Teaching Hospital, Erbil/ Iraq. Eighty participants (46 men and 34 women) received paranasal sinus CT scan to assess their paranasal sinuses and adjacent bone structures. Using the Keros categorization technique, the penetration of the olfactory fossa was determined and categorized into three types, described as type I (1 to 3 mm), type II (4 to 7 mm), and type III (8 to 16 mm). Results: The average penetrations of the left and right olfactory fossa were 6.27±2.19 mm and 5.7±2.03 mm, respectively. Based on the Keros categorization, most of the cases (103) were of type II (64.3%). The right side for both genders was of Keros type II in 63.7%. The association of the right side and the Keros classification was statistically significant (p value = 0.006). Conclusion: For both genders, Keros type II was more predominant. The Keros categorization and the gender variables with respect to the left and right sides respectively, differed significantly.

Keywords

• ct scan
• keros classification
• olfactory fossa