Clinical Significance of Perverted Head-Shaking Nystagmus / 대한평형의학회지

OBJECTIVES: We investigated clinical significance of head shaking nystagmus (HSN) and perverted HSN (pHSN) in patients with peripheral and central vestibular disorders. METHODS: We reviewed medical records of 822 consecutive subjects who were referred to a dizziness clinic. We performed neurologic examination including video-oculography in darkness for 60 seconds before, during and for 100 seconds after head-shaking. HSN was considered to develop when post-head-shaking nystagmus last at least 5 beats with latency from end of head-shaking of no more than 5 seconds, and a velocity at least 3°/sec. RESULTS: In control group (n=45), there were observed spontaneous nystagmus (SN) in 2.2%, HSN in 17.8%, pHSN in 6.7%. In patients with peripheral vestibular disorder group (n=397), there were observed SN in 14.1%, HSN in 40.6%, pHSN in 9.8%. In patients with central vestibular disorder group (n=217), there were observed SN in 17.5%, HSN in 24.0%, pHSN in 13.4%. In unspecified dizziness group (n=208), there were observed SN in 1.9%, HSN in 13.0%, pHSN in 1.9%. pHSN was frequently observed in central vestibular disorders such as stroke, vestibular migraine, cerebellar ataxia, and vertebro-basilar insufficiency. However, pHSN was also observed at higher rate than expected in peripheral vestibular disorders including benign paroxysmal positional vertigo especially involving vertical canals, Meniere disease and even in unilateral vestibulopathy. CONCLUSIONS: Our results show that perverted HSN in dizzy populations was frequently observed not only in cases of central vestibular disorders but also in peripheral disorders. Perverted HSN can develop by any conditions that cause difference in vestibular velocity storage in vertical component of vestibular-ocular reflex.

A Case of Multiple Sclerosis with Isolated Vertigo / 대한이비인후과학회지

Multiple sclerosis (MS) is a chronic disease characterized by multiple areas of demyelination, inflammation, and glial scarring in the central nervous system. MS is the most common chronic and usually progressive neurologic disease whose clinical course varies from a benign and symptom-free disease to a rapidly progressive and disabling disorder. MS can be presented with various symptoms, but isolated vertigo, represented in only 5%, is very rare. Nevertheless, in such a case, differential diagnosis of peripheral vestibular disease is very important for neuro-otologist. We recently experienced a 39 year-old female patient of multiple sclerosis with isolated vertigo mimicking vestibular neuritis. We report our case with a review of literature.

Pseudo-Vestibular Neuritis Caused by a Vascular Tumor Involving the Anterior Inferior Cerebellum / 대한평형의학회지

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.

Apogeotropic Positional Nystagmus in Pontine Infarction / 대한평형의학회지

It is thought that horizontal canal benign paroxysmal positional vertigo (BPPV) is the most common cause of apogeotropic direction-changing positional nystagmus (DCPN). But there are many reports about cerebellar or brainstem lesions as the cause of apogeotropic DCPN. We also report a 72-year-old male patient who showed apogeotropic DCPN, but was proven to have a pontine infarction. The patients complained of disequilibrium which has lasted for 3-4 years and aggravated recently. The symptom was present only when he stood up, and was absent as soon as he sat down. He was not able to successfully perform the Romberg test and tandem gait on physical examination. Vestibular function test revealed apogeotropic DCPN without spontaneous nystagmus. Rotation chair test and caloric test results were all within normal limit. On the brain magnetic resonance imaging, newly detected infarction in the left basal ganglia, pons and right parietal lobe was found. Although horizontal canal BPPV is the most common cause of apogeotropic DCPN, we should be aware that there can be patients with central origin DCPN. In this report, we present the detailed history of this patient and tried to point out the clues to suspect central lesion in patients with apogeotropic DCPN.