Vestibular paroxysmia: a treatable neurovascular cross-compression syndrome

Abstract

The leading symptoms of vestibular paroxysmia (VP) are recurrent, spontaneous, short attacks of spinning or non-spinning vertigo that generally last less than one minute and occur in a series of up to 30 or more per day. VP may manifest when arteries in the cerebellar pontine angle cause a segmental, pressure-induced dysfunction of the eighth nerve. The symptoms are usually triggered by direct pulsatile compression with ephaptic discharges, less often by conduction blocks. MR imaging reveals the neurovascular compression of the eighth nerve (3D constructive interference in steady state and 3D time-of-flight sequences) in more than 95 % of cases. A loop of the anterior inferior cerebellar artery seems to be most often involved, less so the posterior inferior cerebellar artery, the vertebral artery, or a vein. The frequent attacks of vertigo respond to carbamazepine or oxcarbazepine, even in low dosages (200–600 mg/d or 300–900 mg/d, respectively), which have been shown to also be effective in children. Alternative drugs to try are lamotrigine, phenytoin, gabapentin, topiramate or baclofen or other non-antiepileptic drugs used in trigeminal neuralgia. The results of ongoing randomized placebo-controlled treatment studies, however, are not yet available. Surgical microvascular decompression of the eighth nerve is the “ultima ratio” for medically intractable cases or in exceptional cases of non-vascular compression of the eighth nerve by a tumor or cyst. The International Barany Society for Neuro-Otology is currently working on a consensus document on the clinical criteria for establishing a diagnosis of VP as a clinical entity.

Anterior Inferior Cerebellar Arteries Juxtaposed with the Internal Acoustic Meatus and Their Relationship to the Cranial Nerve VII/VIII Complex

“…The relationship of AICA loops to the IAM is a proposed reason for tinnitus resulting from CN VIII compression. Symptoms of vestibulocochlear nerve compression are believed to be caused by direct pulsatile compression with ephaptic discharges [ 15 ].…”

Classification of vestibular signs and examination techniques: Nystagmus and nystagmus-like movements

“…Other peripheral vestibular disorders have been reported to occasionally cause positional nystagmus that must be differentiated from BPPV based on additional symptoms and signs, including vestibular paroxysmia (neurovascular cross-compression of the vestibulocochlear nerve) [25,74], vestibular schwannoma [147], Menière's disease [101], and vestibular atelectasis [162].…”

Benign positional vertigo, its diagnosis, treatment and mimics

“…The positional triggers are generally distinct from BPV ( Strupp et al, 2016 ). Unlike BPV due to canalithiasis, a crescendo-decrescendo pattern of nystagmus is not seen ( Brandt et al, 2016 ). Hyperacusis or unilateral tinnitus may be present during the attack and audio-vestibular tests may show unilateral hypofunction in between attacks ( Hüfner et al, 2008 ).…”