Discussion | Histopathologic studies have shown millimetersize ruptures of the walls of the saccule, utricle, canals, and Reissner's membrane in patients with MD. 1 Schuknecht associated these ruptures with vertigo attacks and proposed the rupture theory. This is consistent with the concept of potassium intoxication in the vestibular sensory epithelium. 5 If ruptures occur during vertigo attacks, EH on MRI scans may diminish and even disappear. However, this patient's bilateral EH remained stable over a long course of repeated vertigo, as shown in Figure 2A-G; however, either ear could be involved in vertigo attacks. Although the current resolution of MRI is insufficient to disprove rupture theory, no large changes in EH (eg, rupture) occurred during this patients' vertiginous episodes.In the absence of past or ongoing evidence of migraine, we attribute this patient's recurrent vertigo attacks solely to MD. Changes in the inner ear, including changes in EH features other than EH volume, may play a role.