**2. Pathophysiology**

After Mc Cabe's report on auto‐immune depended on sensorineural hearing loss in 1979, immunological mechanisms about inner ear pathologies started to be investigated [1]. Many

studies showed that MD is an immune system‐related disease. Autoantibody for the Raf‐1 protein in the membranous labyrinth is found in patients with MD [2]. Elevated IgG immune complexes, auto‐immune response to type II collagen, and focal inflammation with intraepithelial invasion caused by mononuclear cells are shown in endolymphatic sac. This phenomenon is also called "endolymphatic sacitis" [3, 4].

Rarey and Curtis found glycocorticoid receptors on the cochlea and vestibule (especially on the spiral ligament) [5]. Lohuis also showed cell atrophy on stria vascularis after adrenal steroid defects [6]. Glycocorticoid receptors are also found in the lateral wall of cochlea, organ of Corti, modiolus, vestibule, and stria vascularis [7].

It is already shown that steroids regulate inner ear fluid balance with potassium transport channels by mineralocorticoid receptor genes and aquaporin regulation [8, 9]. Cochlear blood flow is also positively affected by topical steroid application [10, 11].

According to these information and steroids' anti‐inflammatory/immunosuppressive effects, we can say that ITS treatment is helpful for MD control.
