Endolymphatic hydrops and its association with Magnetic Resonance Imaging and serum vitamin D levels

OBJECTIVE(S): Endolymphatic hydrops is associated with factors such as autoimmune responses and vascular issues. Vitamin D plays a vital role in immune regulation and is associated with various inflammatory conditions. However, evidence regarding the correlation between endolymphatic hydrops and vitamin D is lacking. We clarified the correlation between vitamin D and endolymphatic hydrops to explain clinical symptoms and intervene in endolymphatic hydrops formation and progression. METHODS: Intravenous gadolinium-enhanced delayed magnetic resonance imaging three-dimensional-fluid-attenuated inversion recovery technique was used to screen unilateral endolymphatic hydrops patients. Vestibular and cochlear hydrops were categorized as follows: 0 = normal, 1 = mild hydrops, and 2 = severe hydrops. Values of low, middle, and high-frequency bands of pure tone audiometry (low-frequency-, middle-frequency-, and high-frequency-pure tone audiometry); serum 25(OH)D3 level; slow phase velocity of bilateral ears in the caloric test; and summating potential to action potential ratio of affected ears in electrocochleography were documented. Correlations between vestibular-cochlear hydrops grade and these examinations were further analyzed. RESULTS: Overall, 82 endolymphatic hydrops patients were included. The grade of vestibular-cochlear hydrops was significantly correlated with the summating potential to action potential ratio and slow phase velocity of the affected ear. A significant linear correlation was observed between the vitamin D level and contralateral ear slow phase velocity and low-frequency-pure tone audiometry value (r = 0.236 and -0.323, respectively). High-frequency-pure tone audiometry and vitamin D levels exhibited correlations with cochlear hydrops (U = 15.06, p = 0.001) and vestibular hydrops (F = 4.394, p = 0.016), respectively. CONCLUSIONS: Vitamin D is directly associated with contralateral slow phase velocity and low-frequency-pure tone audiometry, suggesting its correlation with episodic vertigo and fluctuating hearing loss. Early vitamin D supplementation may improve fluctuating hearing loss and vertigo in Meniere's disease patients with endolymphatic hydrops.