The Role of Frequency Stimulation in Detecting Semicircular Canals Dysfunction in Asymptomatic Vestibular Type 1 Diabetes Mellitus Patients

Abstract Background and Aim: Type 1 diabetes mellitus (T1DM), as a chronic systemic disorder, can affect the physiology of the inner ear, through the development of neuropathy due to microangiopathy. The aim of this study was to investigate the effect of low- and high-frequency stimulation on the detection of dysfunction in the semicircular canals using caloric and video head impulse test (vHIT) and to evaluate central function using oculomotor tests in asymptomatic vestibular T1DM patients. Materials and Methods: In this cross-sectional study, two groups of 17 individuals (11 females and 6 males) including healthy volunteers and T1DM patients without vestibular symptoms, aged between 18 and 40 years, with normal hearing were recruited. T1DM patients with a history of diabetes for more than 5 years were selected. Vestibular tests including videonystagmography (including oculomotor and caloric subtests) and vHIT were performed in both groups. Results: The measured parameters in vHIT, caloric, and oculomotor tests did not show statistically significant differences between the normal and T1DM groups. However, in the interindividual comparison of the T1DM group, only one patient showed a pathological decrease in the average vestibulo-ocular reflex gain of the horizontal semicircular canal in both sides, accompanied by corrective saccades. The caloric and oculomotor test results were within the normal range for this patient. Conclusion: The possibility of subclinical vestibular dysfunction exists in asymptomatic vestibular T1DM patients. Although a specific result cannot be expected for these patients due to the nature of the disease, attention and evaluation of the vestibular system in these patients are suggested.