Can Migraine Damage the Inner Ear?

Abstract

Background Auditory and vestibular symptoms and signs are common in patients with migraine, yet little is known about the pathogenesis of these symptoms and signs.

Objective To perform clinicopathological correlation in a patient with migraine, sudden deafness, and delayed endolymphatic hydrops.

Methods A patient with long-standing migraine with aura developed sudden hearing loss in the left ear at the age of 50 years and Ménière disease on the right side at age 73. At age 76, he had a flurry of sudden drop attacks typical of otolithic crisis. He died of unrelated causes at age 81. The brain and temporal bones were removed approximately 24 hours after death. The cochlea and vestibular end organs were dissected after the surrounding bone was carefully removed.

Results The brain and cerebrovasculature were normal. The left cochlea showed prominent fibrosis consistent with an old infarction. The right inner ear showed hydrops, with relatively good preservation of the hair cells in the cochlea, saccular macule, and cristae of the semicircular canals. However, the utricular macule was denuded of hair cells.

Conclusions The sudden left-sided deafness likely resulted from ischemia, possibly due to migraine-associated vasospasm. Presumably, the right ear suffered only minimal damage when the patient was 50 years old, but this damage later led to the development of delayed endolymphatic hydrops on the right. Otolithic crises are thought to result from pressure changes across the utricular macule. We speculate that loss of hair cells in the utricular macule resulted from a collapse of the utricular membrane onto the macule.

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MIGRAINE is a common disorder whose most readily recognized manifestation is headache. However, many patients with migraine also suffer from episodic vertigo.1- 4 Infrequently, episodic vertigo may even be the only manifestation of migraine (a migraine equivalent).5 Although auditory symptoms are generally considered to be less common than vestibular symptoms with migraine,6 migraine can cause fluctuating low-frequency hearing loss and sudden deafness.7,8 Vasospasm of labyrinthine arteries might explain all of these inner ear symptoms.6,8

Delayed endolymphatic hydrops occurs in patients with long-standing unilateral profound hearing loss.9,10 Presumably, minor damage to the endolymphatic sac at the time of the deafness leads to impaired endolymphatic resorption and the development of hydrops years later. Schuknecht et al10 noted that hydrops often develops in the ear that is contralateral to the deaf ear and speculated that a systemic viral infection could cause the deafness and subclinical damage to the endolymphatic sac in either ear. Some patients with delayed endolymphatic hydrops manifest dramatic drop attacks that are thought to result from sudden pressure changes across the otolithic receptors (otolithic crises).11 However, to our knowledge, inner ear abnormalities have not been reported in such patients.

We present a clinicopathological correlation in a patient with life-long migraine with aura but without other vascular risk factors who developed sudden deafness in his left ear at the age of 50 years. Twenty-three years later, he developed endolymphatic hydrops in his right ear, along with typical otolithic crises. Based on the findings, we propose that migraine-associated vasospasm caused the sudden deafness in the left ear and the subclinical damage to the endolymphatic sac in the right ear, predisposing to the development of delayed endolymphatic hydrops. A severe loss of hair cells in the utricular macule on the right side probably resulted from collapse of the utricular membrane onto the macule.