Assesment of vestibular system with video head impulse test in hyperthyroid and hypothyroid patients

The purpose of the study was to evaluate video head impulse test findings in hypothyroid and hyperthyroid patients. The study included 25 hypothyroidism patients, 25 hyperthyroid patients and age-sex matched 20 patients who were accepted to participate in the study between 25-60 years of age in Ankara Yıldırım Beyazıt University Yenimahalle Training and Research Hospital. All subjects participating in the study were evalueted pure tone audiometry, speech audiometry and vHIT. When the patient groups and the control group vHIT results were evaluated, the hypothyroid group was not at the pathological level in the left lateral canal and in the left posterior canal of both groups of patients but a statistically significant decrease was observed. Overt and covert saccades were not dedected in any group when evaluated in terms of the presence of saccades. When asymmetry was considered between groups, statistically significant asymmetry was observed in RALP canal in hyperthyroid patients. It has been demonstrated that hyperthyroidism and hypothyroidism do not affect the pathological level of vHIT results. Although there are normative data, statistically significant differences between the patient group and the control group in this study raises questions about the sensitivity of normative data's cut-off values. There is a need for further studies with large samples in order to examine the normative values that contain appropriate limits for detecting the disorder and to shed light on the normative data differences in the literature. Keywords: Hyperthyroidism, hypothyroidism, video head impulse test, vHIT, vestibulo- ocular reflex