Comparison of Lateral Semicircular Canal Dysfunction in Chronic Otitis Media Patients using Air Caloric Test and Video Head Impulse Test

In developing nations like India, chronic otitis media (COM) is a common middle ear ailment that has serious ramifications for both hearing and quality of life. Long-term inflammation of middle ear cavity and tympanic membrane are the hallmarks of COM, which can result in consequences like facial paralysis, labyrinthitis, hearing loss, and potentially fatal cerebral abscesses. The effect of COM on vestibular function is still unknown. Studies reveal a positive correlation between the severity of COM and vestibular impairment, which may point to a cause-and-effect link. Using air caloric testing and video head impulse testing (VHIT), this study seeks to explore the link between vestibular symptoms, particularly lateral semicircular involvement with COM. To quantify the involvement of lateral semicircular canal using air caloric test and video head impulse test, compare the results of both tests in patients with chronic otitis media and to detect early labyrinthine dysfunction using air caloric test and Video head impulse test. A cross-sectional study was conducted over a period of 2 years to investigate the involvement of the lateral semicircular canal in patients aged 18 years and above with symptoms suggestive of chronic otitis media. All patients underwent air caloric and video head impulse tests, to evaluate canal paresis and horizontal vestibulo-ocular reflex (VOR). The outcomes of both tests were compared to investigate their correlation and diagnostic value. A total of 145 patients were enrolled in this study, with a median age range of 30-39 years and the gender distribution was nearly equal. The majority of patients (85.5%) presented with mucosal type chronic otitis media (COM), while 14.5% had squamosal type COM.Video head impulse test (VHIT) revealed abnormalities in 45.5% of patients, whereas the air caloric test (ACT) showed abnormalities in 21%. A positive head impulse test was observed in 11 patients (14.5%). Patients with medium and large-sized central perforations were more prone to giddiness. Labyrinthine fistula was detected in one patient with active squamosal disease. 56.1% of patients with abnormal VHIT had normal canal paresis and only 29 patients (43.9%) showed both abnormal VHIT and Air caloric test. VHIT is found to be more sensitive compared to air caloric test. The study highlights the significance of utilising both VHIT and ACT in the comprehensive evaluation of vestibular function in patients with COM. For individuals with vestibular deficits due to COM, a combined approach can improve diagnostic accuracy and guide targeted therapy and rehabilitation options.