The first attack of Ménière's disease: A study through SVV perception, clinical and pathogenetic implications

Abstract

This is a study of Subjective Visual Vertical (SVV) perception during acute attacks of Ménière's disease (MD) with comparative evaluation of concurrent nystagmus. We studied 21 patients with unilateral MD during the acute phase and 7 days later. Of the nine patients with an initial attack of MD, seven had an alteration of SVV perception and of these, three indicated a match with canal functional signs, while four patients showed an opposite trend of SVV perception relative to the spontaneous nystagmus. Nine of the 12 patients with definite MD had a pathological SVV perception always in correspondence with the same type of canal event. At 1-week control, no patient with an initial MD attack had alteration of SVV perception, whereas 5 patients with definite MD presented a pathological SVV perception toward the affected side. In the course of acute attacks of unilateral MD, clinical manifestations may include otolithic involvement and this may have an opposite trend compared to concomitant canal signs, especially during initial attacks. This behavior allows us to distinguish clinical signs of maculo-canal "correspondence" and "dissociation" with a significant prevalence of the second indication in those subjects with an initial MD attack.

Subjective Visual Vertical and Vestibular Evoked Myogenic Potential in Meniere's disease

“…SVV alterations have also been mentioned in MD. 29 , 37 , 38 , 42 , 43 SVV deviation to the side of the lesion and to the opposite side in unilateral MD and without lateralization in bilateral MD has also been found. 30 Abnormal inter-crisis SVV in vestibulopathies suggests insufficient vestibular compensation.…”

“…Endolymphatic hydrops can affect the otolith structures; functional disorders of the saccule and utricle can be recognized by cVEMP, oVEMP 28 and SVV. 29 …”

Subjective Visual Vertical Perception in Peripheral Vestibular Diseases

“…Moreover, in this group, when comparing SVV with SN, an opposite functional status (configuring the so-called "maculo-canal dissociation") was significantly more frequent than the definite MD group. These findings would reflect both the pathogenesis and the progression of MD [19]. More in detail, the increase in the endolymphatic hydrostatic pressure would not begin in a synchronous manner in all vestibular compartments because of the different caliber of membranous components.…”

Skull-vibration-induced nystagmus test in patients who are candidates for intratympanic gentamicin injection

“…Spontaneous nystagmus can be observed during episodes and the related vestibular tests give rise to responses that express a paretic (deficit) or irritative functional state. However, it is often possible to record opposing responses that express a functional dissociation in both the frequency (caloric vs video Head Impulse Test) and topographical domain (macular vs canal clinical signs) 9 , 10 .…”