The relationship between audiometric findings and CT analysis in patients with otosclerosis: a cross-sectional study

Abstract Background Otosclerosis is characterized by abnormal bone remodeling in the middle ear, leading to conductive hearing loss. While audiometric findings are valuable in diagnosing this condition, Temporal HRCT also plays a helpful role in identifying secondary causes and diagnosing the disease. Due to conflicting views on the diagnostic significance of both procedures, this study aimed to determine the correlation between audiometric findings and CT scans in patients with otosclerosis. Methods Forty-one patients referring to Otolaryngology departments of Ghaem and Imam Reza hospitals, were enrolled in this cross-sectional study. Speech recognition threshold (SRT) and pure tone audiometry (PTA-air conduction, bone conduction, and air–bone gap) were calculated for each patient. CT scan was performed for all patients, assessing lesion size and bone density in the fissula ante fenestram. The hypodense area size was measured as a region of interest, focusing on the specified area in the images, including the hypodense regions. Finally, the extent of audiometric correlation with CT findings were assessed using appropriate statistical tests. Results Twenty-three subjects (56.1%) exhibited well-defined hypodense lesion in the fissula ante fenestram, while 8 individuals (19.5%) showed cochlear involvement. There was no significant difference in terms of age ( P = 0.065), gender ( P = 0.091), and right/left position ( P = 0.350) between patients with and without normal area. No significant correlation was also found between the audiometric findings and the presence of well-defined hypodense lesion in the fissula ante fenestram in CT scan, both before and after surgery ( P > 0.05). However, the changes in mean SRT and PTA at 2 kHz were found to be significantly higher in the group with cochlear involvement compared to those without cochlear involvement ( P = 0.001). Conclusion Our findings indicated no significant correlation between the results of CT scans and audiometric findings. Therefore, relying solely on audiometry may provide a reliable assessment of the extent of otosclerosis in the inner ear, especially when access to a CT scan is not possible.