Ocular counter-roll during a Mŕnière’s attack: evidence of ictal utricle pathway imbalance using fundus photography (P3-9.004)

Abstract

<h3>Objective:</h3> To call attention to unrecognized ictal vestibular manifestations of Mŕnière’s disease. <h3>Background:</h3> During Mŕnière’s disease (MD) attacks, static semicircular canal (SCC) asymmetry causes spontaneous nystagmus (ipsilesional when excitatory, and contralesional when inhibitory). Acute dynamic SCC dysfunction can cause an abnormal head impulse test (HIT, e.g., acute vestibular neuritis), although the HIT can be normal during a MD attack. Documentation of ictal otolith (utricle and saccule) dysfunction using vestibular evoked myogenic potentials (VEMPs) has rarely been reported. We describe the first case, to our knowledge, of a patient presenting with a Mŕnière’s attack in whom an ocular counter-roll (OCR, from static utricle pathway imbalance) was documented using fundus photography. <h3>Design/Methods:</h3> One case report of a patient with an OCR observed during a MD attack. <h3>Results:</h3> A 65-year-old man with known history of bilateral MD presented during a typical vertigo attack, and testing demonstrated: 1) Video-oculography (VOG) – spontaneous horizontal-torsional, unidirectional right beating nystagmus, following Alexander’s law; 2) Video HIT (vHIT) – low gain (0.49 where &lt;0.7 is considered abnormal) in the plane of the left horizontal SCC; 3) fundus photography – OCR with the top poles of both eyes rotated toward the left ear, in the absence of other features of the ocular tilt reaction (OTR, including OCR, head tilt, skew deviation). The HINTS exam (head impulse, nystagmus, test of skew) suggested a left peripheral vestibulopathy, and a Mŕnière’s attack was diagnosed given his history. Three weeks later testing was repeated while asymptomatic: 1) VOG – no nystagmus; 2) vHIT – normal horizontal SCC gain (0.73); 3) fundus photography – no OCR. For more, visit the NOVEL collection: https://collections.lib.utah.edu/ark:/87278/s6k97g27 <h3>Conclusions:</h3> Using a non-mydriatic fundus camera, we were able to document an ictal OCR in MD. Its presence suggested utricle pathway imbalance, offering insight into the labyrinthine structures that may be involved during a MD attack. <b>Disclosure:</b> Dr. Fracica has nothing to disclose. Dr. Gold has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Springer .