ABSTRACT
The authors highlights the importance of the vestibulo-ocular reflex examination through the head impulse test as a diagnostic method for vestibular dysfunction as well as, and primarily, a bedside semiotic resource capable of differentiating between acute peripheral vestibulopathy and a cerebellar or brainstem infarction in emergency rooms.
Os autores ressaltam a importância do exame do reflexo vestíbulo-ocular por meio do teste do impulso da cabeça como método diagnóstico de hipofunção vestibular. Este método é também - e principalmente - um instrumento semiótico de beira do leito capaz de auxiliar no diagnóstico diferencial entre a vestibulopatia periférica aguda e o infarto cerebelar ou do tronco cerebral na sala de emergência.
Subject(s)
Humans , Cerebellar Diseases/diagnosis , Cerebral Infarction/diagnosis , Reflex, Vestibulo-Ocular/physiology , Vestibular Diseases/diagnosis , Vestibular Function Tests/methods , EmergenciesABSTRACT
Acute vestibular syndrome (AVS) is characterized by the rapid onset of dizziness/vertigo accompanied by nausea/vomiting, gait unsteadiness, and nystagmus lasting a day or more. Some patients with AVS have potentially dangerous central etiologies. AVS caused by central etiologies without significant other neurologic deficit, so called pseudo-vestibular neuritis (pseudo-VN), could be difficult to be differentiated from acute vestibular neuritis. In addition to imaging studies, bedside oculomotor examination-head impulse test, nystagmus and test of skew)-is essential to identify patients with pseudo-VN. Among several central causes of AVS, brain tumor is extremely rare. We report a case of vascular tumor involving the anterior inferior cerebellum with AVS presentations.
Subject(s)
Humans , Brain Neoplasms , Cerebellum , Gait , Neuritis , Neurologic Manifestations , Nystagmus, Pathologic , Vertigo , Vestibular NeuronitisABSTRACT
Acute vestibular syndrome characterized by vertigo, spontaneous nystagmus, and postural instability is caused by a unilateral injury to either peripheral or central vestibular structures. However, central vestibular syndromes, such as labyrinthine ischemia due to occlusion of anterior inferior cerebellar artery (AICA), may cause abrupt unilateral labyrinthine dysfunction that mimics peripheral vestibulopathy. Here we report an AICA infarction with isolated flocculus lesion on magnetic resonance imaging mimicking acute labyrinthitis with vertigo, unidirectional horizontal-torsional nystagmus, ipsilesional sensorineural hearing impairment, and positive head-thrust test without any typical findings of floccular lesion.