Apo-and Geotropic Horizontal Nystagmus Mimicking Benign Paroxysmal Positional Vertigo in Vestibular Migraine Patients: The Clinical Cases

Abstract

Symptoms of vestibular migraine (VM) are often indistinguishable from vestibular symptoms caused by other pathologies, such as benign paroxysmal positional vertigo (BPPV). Episodic positional vertigo is typical for both disorders. We observed two cases of apo- and geotropic positional nystagmus mimicking BPPV in patients previously diagnosed as having migraine (MIG). Positional nystagmus detected in our patients was not typical for horizontal canal BPPV (canalolithiasis/cupulolithiasis): it had low velocity, persisted as long as the provoking position was maintained, had no crescendo- decrescendo pattern and nearly symmetrical intensity on both sides. Multiple canalith repositioning maneuvers failed, although pseudo-BPPV incidences disappeared two weeks after starting intensive anti-MIG treatment. Previous history of migraine, accompanying migrainous features (One-sided headache, long duration, associated with nausea and/or vomiting, photophobia and phonophobia), nystagmus characteristics, ineffective response to positional maneuvers, contrary, favorable response to anti-MIG medications, make it much easier to differentiate these two disorders: VM and BPPV.