Persistent Nystagmus in Chronic Phase of Lateral Medullary Infarction

Background@#and PurposeWe aimed to determine the patterns and mechanisms of persistent nystagmus (PN) lasting >1 year in lateral medullary infarction (LMI). @*Methods@#We recruited 13 patients with PN due to LMI and another 13 with transient nystagmus (TN) (<1 year) as control. All patients underwent oculography, rotatory chair test, caloric test, bedside head impulse test, dizziness handicap inventory (DHI), and brain MRI. @*Results@#All patients had spontaneous, contralesional, horizontal-torsional nystagmus during the acute phase. Although two patients exhibited consistent contralesional torsional nystagmus, most patients (11/13, 85%) with PN evolved from the initial contralesional to ipsilesional nystagmus. During horizontal gaze, the patterns of ipsilesional PN were diverse; torsional (n=5), torsional-downbeat (n=2), horizontal (n=2), and horizontal nystagmus while looking at the lesion side, and torsional nystagmus while looking at the opposite side (n=2). During rotatory chair test, the gains of the vestibulo-ocular reflex in the PN group were lower than those in the TN group to the lesion side at 0.02 and 0.64 Hz. The caudal and ventrolateral parts of the vestibular nuclei were mostly involved in patients with PN. The DHI score did not differ between the groups. @*Conclusions@#PN patterns frequently change in LMI. Resultant vestibular asymmetry after vestibular afferents or cerebellar inhibitory pathway damage and/or inappropriate vestibular compensation may be responsible for PN in LMI. Impairment of the horizontal or vertical neural integrators may be another cause. The presence of PN does not necessarily indicate more severe dizziness in LMI.

Cardiovascular Risk Factors in Total or Divisional Vestibular Neuritis / 대한평형의학회지

OBJECTIVES: In vestibular neuritis (VN), the lesion preferentially affects the superior vestibular nerve because of the anatomic arrangement. It is well known that VN patients have a higher score of metabolic syndrome or a higher incidence of vertebral artery hypoplasia than controls. However, it is unclear whether the frequency of cardiovascular risk factors can affect the selective involvement of the branch of the vestibular nerve. Thus, we investigated the influence of cardiovascular risk factors on the development of total- or divisional VN. METHODS: 61 patients with VN were enrolled. Video head impulse tests and caloric tests were performed to determine which vestibular divisionswere affected. The patients were divided into divisional-VN (superior or inferior) and total-VN groups. Statistical analysis of the frequency of cardiovascular risk factors was performed only in superior and total VN groups because the number of inferior VN patients was too small to be statistically analyzed. RESULTS: Nineteen (31.1%) patients were classified as the total-VN group. In the divisional-VN group (42 patients, 65.6%), 40 were superior VN. The frequency of cardiovascular risk factors are not significantly different in superior VN and total-VN groups (All patients 50/61 [82.0%], superior-VN 36/40 [90.0%], total-VN 13/19 [68.4%]). The frequency of having more than one cardiovascular risk factor was slightly higher in the superior VN group, (13 [68.4%] vs. 36 [90.0%], p=0.062) but did not show any significant difference. CONCLUSIONS: The number of cardiovascular risk factors did not differ in superior VN patients compared to total VN patients.

Vestibular Dysfunctions in Vestibular Migraine Evaluated by Rotatory Chair Test / 대한평형의학회지

OBJECTIVE: There have been several efforts to elucidate the pathophysiology of the vestibular migraine (VM). But, there is no consistent result. This study was to identify the possible pathophysiology of VM by comparing vestibulo-ocular reflex (VOR) parameters between VM, and the tension type headache (TTH) patients. In addition, we compared VOR parameters between ictal and interictal period in the VM group. METHODS: Seventy eight patients were included: 44 having VM and 34 TTH. Three parameters (gain, asymmetry, and phase) of the horizontal VOR rotating at 60 degrees were measured. In 10 VM patients VOR parameters were obtained twice sequentially first in the ictal and second in the interictal period. RESULTS: Although the average of the VOR gain in VM group was lower than that of TTH group but there was no statistical significance. An asymmetry of the VOR was significantly higher in VM group. There were various changes in other VOR parameters between ictal and interictal periods with no consistent trends. CONCLUSION: We could deduce that VM patients might have subclinical vestibular dysfunction from the reduced gain and increased asymmetry of the VOR in the interictal period. Dynamic changes of the VOR in the ictal period could be responsible for dizziness in VM patients, which are caused by the pathological alteration of the physiologic plasticity of the VOR.

Assessment of Vestibular Functional Recovery Using Video Head Impulse Test in Vestibular Neuritis / 대한평형의학회지

OBJECTIVE: The video head impulse test (vHIT) is useful for evaluation of high frequency vestibulo-ocular reflex. There are a few reports regarding the recovery of head impulse test in vestibular neuritis (VN) but the factors for the recovery were not studied. The study aimed to identify the recovery patterns of vHIT in VN and the factors influencing the recovery. METHODS: Among 31 patients with acute VN, 18 patients with identified recovery pattern were selected. We conducted serial checks of subjective vertigo and spontaneous nystagmus until discharged (1-8 days), and scheduled vHITs. We found three patterns in serial vHITs during follow-ups and analyzed the relationship of initial vestibular function tests, serial check-ups of subjective vertigo, bedside neuro-otologic tests, and vHITs. RESULTS: Five patients showed normal vHIT gain in acute stage (non-damaged pattern) and 8 patients' gains were recovered after 30 days after symptom onset (early recovered pattern). Poor recovery pattern was found in 5 patients (poorly recovered pattern). There were relationship between vHIT recovery patterns and the severity of vestibular dysfunctions. Duration of spontaneous nystagmus (until grade 1), degree of subjective visual vertical tilt, ocular vestibular myogenic potential abnormalities, and abnormality of rotatory chair test were all related to poorly recovered vHIT patterns. All poor recovery patients had residual symptom at 30 days after symptom onset. CONCLUSION: The vHIT may give clinicians useful hints in predicting prognosis in VN, and the recovery of vHIT would be delayed if the damage were more extensive.

The Clinical Characteristics according to the Educational Level in the Elderly Patients with Mild Alzheimer's Disease Dementia

BACKGROUND AND PURPOSE: Cognitive reserve is important for the individual susceptibility to dementia. Among the various determinants of cognitive reserve, the number of years of formal education would be of prime importance. We performed this study to explore its contribution to the clinical characteristics of dementia. METHODS: We included consecutive mild Alzheimer's disease (AD) dementia patients (clinical dementia rating, CDR=0.5 or 1) who visited our memory clinic and were older than 70 years at the evaluation from October 2013 to September 2015. According to the number of years of education, the corresponding subjects was grouped into two extreme educational groups, low education (illiterate or partially illiterate, LE, n=43) vs. high education (more than 9 years of education, HE, n=34). Among these patients, we compared various demographic, neuropsychological and neuroimaging characteristics. RESULTS: The groups were comparable in terms of age, frequency of hypertension and diabetes, and CDR and its sum of box. However, female gender was more frequent in the LE group (p=0.000). Also this group showed a more depressive mood on the geriatric depression scale (p=0.007). The raw scores on Korean Version of Mini-Mental State Examination and well-validated neuropsychological tests were lower in the LE group. However, the cognitive performance was found to be more preserved in the LE group than in the HE group when assessed using the z-score in certain specified tests on univariate and multivariate analyses (p<0.05). The Schelten's grade of medial temporal atrophy was similar between the two educational groups. Also, the degree of combined ischemic burden did not differ between the two groups. CONCLUSIONS: We identified that the prevalence of depressive mood and the extent of decline from the corresponding norm in a particular neuropsychological performance differ according to the educational level of mild AD patients.

Clinical Characteristics in Lacunar Infarction with Less Than 50% Stenosis in the Parent Artery

BACKGROUND: Contrary to the initial hypothesis, there is accumulating evidence that the pathogenesis of lacunar infarction (LI) is heterogeneous. LI is often accompanied by intracranial stenosis, and while the clinical significance of severe stenosis of the intracranial parent artery in LI has been demonstrated, that of mild stenosis in LI has not been. Thus the aim of this study was to determine the clinical relevance of mild intracranial stenosis in LI. METHODS: Ninety-three consecutive patients with acute LI were enrolled between March 2011 and December 2013. The patients were divided according to the presence of intracranial stenosis in the parent artery into pure LI (PLI) and LI with mild intracranial stenosis (<50% stenosis, BAD). Various clinical and laboratory characteristics were compared between the two groups. RESULTS: PLI group were older and, had a less frequent history of smoking, a larger infarct, lower likelihood of a favorable outcome, and higher National Institute of Health Stroke Scale score at discharge in the univariate analysis. After adjusting for confounding factors, BAD was associated with older age at onset [odds ratio (OR) = 1.113, 95% confidence interval (95% CI) = 1.056-1.172, p<0.001), no history of previous statin medication (OR = 13.362, 95% CI = 1.014-176.062, p=0.049), and nonsignificant stenosis in the parent artery was associated with larger infarct (beta=0.296, p=0.01) in the multivariate analyses. CONCLUSIONS: LI with mild parent-artery disease was demonstrated to have distinct clinical characteristics compared to LI without parent artery disease. Thus, even mild branch atheromatous disease in LI should be evaluated thoroughly and treated via a planned and systematic approach.

Comparison of Audiovestibular Dysfunction in Patients of Acute Unilateral Peripheral Vestibulopathy with and without Vascular Risk Factors / 대한평형의학회지

BACKGROUND AND OBJECTIVES: Etiology of acute unilateral peripheral vestibulopathy (AUPV) includes virus, ischemia, and autoimmune. As anatomical distribution is similar between vasculature and innervation, AUPV with vascular risk factors could be ischemic origin. We investigated the pattern of audiovestibular dysfunction to explore the influence of risk factors on AUPV. MATERIALS AND METHODS: We collected records of 162 AUPV patients from 2011 to 2013 who were admitted within 7 days from vertigo onset and diagnosed as AUPV by caloric test and neuro-otologic examination. Vascular risk factors are stroke history, hypertension, diabetes, body mass index >25, age >60, and vertebrobasilar stenosis. Bedside examination includes spontaneous nystagmus grade, head impulse test, head shaking test. Results of rotatory chair test (n=125), caloric test (n=162), cervical (n=33) and ocular (n=23) vestibular evoked myogenic potential (VEMP), subjective visual vertical (SVV) (n=91), and pure tone audiometry (PTA) (n=62) are collected. RESULTS: Abnormalities of PTA are found more in patients with vascular risk factor than without any risk factor. Specifically, hypertension (p=0.008) and old age (p=0.025) are associated with PTA abnormality (p=0.006). Tilt angle of vertical is larger in risk factor group (p=0.019). The number of vascular risk factor correlates with abnormalities of PTA (p=0.025) and tilt angle of SVV. Results of bedside examination, rotatory chair test, caloric test, cervical and ocular VEMP are not associated with vascular risk factors. CONCLUSION: AUPV patients with vascular risk factors have more extensive involvement of audiovestibular function. Ischemic etiology may contribute to pathogenesis of extensive AUPV.

Predictors of Cerebrovascular Causes in the Emergency Department Patients with Dizziness: Application of the ABCD2 Score / 대한평형의학회지

BACKGROUND AND OBJECTIVES: Dizziness is a common presenting complaint in the emergency department (ED) that had various pathologic causes. Most of dizziness can be caused by benign origin but identifying cerebrovascular causes among ED patients with dizziness is a diagnostic challenge. ABCD2 score is clinical prediction tool for assessing the risk of stroke after a transient ischemic attack. We evaluated predictors of cerebrovascular causes and whether ABCD2 score would identify cerebrovascular events among ED patients with dizziness. MATERIALS AND METHODS: We analyzed 180 patients (> or =20 years old) with dizziness in ED, Presbyterian Medical Center (single-center prospective observational study) for 2 months. Type of dizziness, associated symptoms, past medical history, ABCD2 score (0-7), neuro-otologic examination, diagnosis were recorded. RESULTS: The incidence of dizziness is 3.6% (192/5,374). After excluding 12 patients, 180 patients (56% female, mean 59 years) met our eligibility criteria and were included in the final analysis. Cerebrovascular causes of dizziness were found in 10% (18/180): 3 vertebrobasilar insufficiency, 9 cerebellar infarction, 1 right middle cerebral artery (MCA) infarction, 1 right MCA giant aneurysm, 1 lateral medullary infarction, 1 posterior limb of internal capsule infarction, 1 intracerebral hemorrhage of cerebellum. Patients with cerebrovascular cause were males and had more hypertension, diabetes mellitus, imbalance, abnormal neuro-otologic findings and ABCD2 score. CONCLUSION: Several clinical factors (hypertension, diabetes, abnormal neuro-otologic findings ABCD2 scores) favored a diagnosis of central neurological causes of dizziness. ABCD2 score is a simple and easily applied tool for distinguishing cerebrovascular from peripheral causes of dizziness in ED.

Serial Positron Emission Tomography Findings and Neuropsychological Assessments in Limbic Encephalitis

OBJECTIVE: Limbic encephalitis (LE) is characterized by rapid development of impaired cognitive function, seizure and psychiatric symptoms. Brain 18fluoro labelled deoxyglucose (18FDG)-positron emission tomography (PET) typically showed glucose hypermetabolism in the temporomesial region in the acute stage. Although several studies about brain 18FDG-PET in LE have been reported, serial 18FDG-PET findings during the course of the disease are limited. The purpose of this study is to analyze serial 18FDG-PET findings in LE and to compare them with the results of neuropsychological test. METHODS: We studied prospectively two patients diagnosed as LE using clinical criteria. They underwent serial brain magnetic resonance imaging (MRI) and 18FDG-PET scans. They also received detailed neuropsychological tests. RESULTS: Initial 18FDG-PET presented glucose hypermetabolism in unilateral temporomesial region without obvious abnormalities in brain MRI. Follow-up 18FDG-PET images obtained three month later displayed hypometabolism in both temporomesial region. Correspondingly, neuropsychological studies revealed prominent visuospatial and verbal memory deficits. CONCLUSION: The initial 18FDG-PET was very sensitive in visualizing the disease process compared with MRI and suggesting more markedly functional impairment than structural damage in early stage of LE. This was well correlated with cognitive dysfunction measured by neuropsychological test such as anterograde episodic memory loss involving both verbal and non-verbal materials.

Leucine-rich, Glioma Inactivated 1 Antibody-related Limbic Encephalitis Presenting as Recurrent Complex Partial Seizures

No abstract available.

Pathophysiology of Nystagmus in Benign Paroxysmal Positional Vertigo / 대한평형의학회지

Benign paroxysmal positional vertigo (BPPV) is easily diagnosed when the specific pattern of nystagmus is demonstrated by adequate provoking maneuver. Therefore, recognizing the pattern of nystagmus is important to determine the affected ear and whether the otoconia is free-floating in the canal or attached to the cupula. However, the latency and the duration of nystamus can be various depending on the type of otoconia and even the direction of nystagmus is atypical in some cases. In addition, not all the positionally-induced nystamus are ascribed to benign semicircular canal pathology. Atypical pattern and refractory for the canalith repositioning maneuver can raise the possibility for the central positional vertigo or nystagmus. Physicians are often perplexed if the pattern of nystagmus by positioning maneuver is not the expected one. For those account, physicians should be well equipped with the knowledge of the pathophysiology of nystamus in BPPV. The pathophysiology and the various patterns of nystagmus in BPPV are discussed in this review.

Pulsatile Tinnitus Caused by Arteriovenous Fistula of External Carotid Artery

Isolated pulsatile tinnitus is a rare condition in patients with neurological disorders but can be the only clue to a potentially life-threatening disease such as intracranial vascular malformation. We report a patient with pulsatile tinnitus caused by an arteriovenous fistula of the external carotid artery, which was successfully treated with coil embolization.

The Relations of Otholith Function Tests and Risk Factors of Benign Paroxysmal Positional Vertigo / 대한평형의학회지

BACKGROUND AND OBJECTIVES: Since the liberated otoconia from the degenerated utricle has been postulated as the cause of the benign paroxysmal positional vertigo (BPPV), the relationship of the utricular function and the generation of BPPV have been studied. In addition, abnormal bone metabolism and vascular risk factors resulting insufficient circulation to utricle has been reported to be related to the utricular degeneration in BPPV. We investigated the relationship between the vascular risk factors, bone mineral density (BMD) and recurrence for the BPPV and otholith function tests of BPPV. MATERIALS AND METHODS: Consecutive patients 84 with BPPV were recruited in a dizziness clinic. Caloric test, ocular vestibular evoked myogenic potentials (oVEMPs) were tested in all the patients in acute phase of BPPV. At the same time, vascular risk factors and BMD were performed. Vascular risk factors were history of hypertension, diabetes mellitus, hyperlipidemia and ischemic heart disease. All the data were analyzed for the relationship between abnormal results of vestibular function tests and the risk factors. RESULTS: Patients 58 (69%) showed abnormal cervical VEMPs that were related to decreased bone density, having more than one vascular risk factor, and older age (>55 years). Abnormal oVEMPs were showed in 53 patients (63%) that were related to older age and vascular risk factors, but not statistically related to bone mineral density. Caloric tests failed to show any statistically significant results. CONCLUSION: We found abnormal results of cVEMPs and oVEMPs is related to the BMD, vascular risk factors and age. VEMPs could be used for the demonstration of presumptive otolith degeneration in BPPV.

Non-Convulsive Status Epilepticus as a Manifestation of Hashimoto's Encephalopathy

No abstract available.

Secondary Hyperkalemic Paralysis Mimicking Demyelinating Sensorimotor Polyneuropathy

No abstract available.

Predictors of Antiplatelet Treatment Failure in Noncardioembolic Stroke

BACKGROUND: The purpose of this study is to identify the differences of risk factors and stroke mechanism between early and late recurrence in patients with long-term antiplatelet therapy for stroke prevention. METHODS: We enrolled 114 consecutive patients with recurrent infarction who had been taking antiplatelet agents regularly since previous noncardioembolic cerebral infarction. Total 81 patients (49 men and 32 women) were met to the inclusion criteria through standardized evaluation. Subjects were classified into two groups depending on the time-to-recurrence after antiplatelet therapy: early antiplatelet failure (within 2 years, n=41, hereafter as "EAF") and later antiplatelet failure (after 2 years, n=40, hereafter as "LAF"). We investigated the differences of clinical factors between two groups using univariate and multivariate analysis. RESULTS: Family history of stroke (29.3% in EAF vs. 10% in LAF, p=0.029) was more frequent in EAF group. Low HDL-cholesterol and High total cholesterol/HDL-cholesterol ratio were associated with the LAF group (p=0.042, 0.005 respectively). Multivariate analysis showed that family history of stroke (OR=5.283, 95%CI 1.178-23.699, p=0.030) and previous infarction classified as large artery atherosclerosis (OR=8.497, 95%CI 1.444-50.015, p=0.018) were significant predictors for EAF whereas total cholesterol/HDL-cholesterol ratio (OR=2.002, 95%CI 1.183-3.389, p=0.010) was for LAF. CONCLUSIONS: This study suggests that family history of stroke and cerebral infarction due to large artery atherosclerosis are more responsible for the early recurrence while dyslipidemic condition is more related to the late recurrence during long-term antiplatelet therapy in patients with previous cerebral infarction.

Prognosis of Hearing According to the Presence of Recurrent Vertigo in Meniere's Disease / 대한평형의학회지

BACKGROUND AND OBJECTIVES: In Meniere's disease, the relationship between the vertigo attacks and prognosis of hearing remains unclear. Our study aimed to elucidate the possible role of recurrent vertigo in the prognosis of hearing in Meniere's disease. MATERIALS AND METHODS: The medical records of 53 patients with definite Meniere's disease over 2 years follow-up were analyzed retrospectively and we analyzed the changes of vertigo and hearing over time. RESULTS: While 49% of patients who were treated conservatively experienced recurrent vertigo attacks, 40% of patients did not have an episode of vertigo during the follow-up. Worsening of hearing and fluctuation were found in about 30% and 26%, respectively. There is no obvious coincidence in the course of vertigo and hearing. CONCLUSION: The prognosis of hearing dose not depend on the the presence of recurrent vertigo in Meniere's disease.

Relationship Between Clinical Features and Recurrence in Benign Paroxysmal Positional Vertigo of Posterior Semicircular Canal / 대한평형의학회지

BACKGROUND AND OBJECTIVES: The aim of this study is to evaluate the relationship between the recurrence and clinical features of posterior canal benign paroxysmal positional vertigo (p-BPPV). MATERIALS AND METHODS: Eighty one consecutive patients with p-BPPV in 1 year period were selected and traced for 2 years by telephone interview and chart review. We reviewed the clinical chart to confirm the lesional side of semicircular canals when 13 patients of the recurrent groups had readmitted. We compared clinical characters between the recurrent group and the nonrecurrent group. RESULTS: The recurrence rate after the successful treatment in the p-BPPV is 28% (23/81) patients. There was no difference in the age, sex, and days prior to visit between the recurrent group and the nonrecurrent group (72%, 58/81). The interval to recurrences were ranged from 8 days to 24 months. In the patients we could confirm the side of recurrences (13/23), there was a tendency of recurring on the same side in the early recurrences (within 14 days) (4/13). CONCLUSION: In considering the causes, the fact that early recurrences tend to be on the same side may be related to unilateral otolith dysfunction as the cause of recurrences in p-BPPV. But the late recurrence may be related to systemic condition because recurrent BPPV developed equally on both sides.

Primary Position Downbeat Nystagmus During Acute Vestibular Migraine

Only a few cases of primary position downbeat nystagmus (PPDN) during an acute vestibular migraine (VM) have been reported but without details of the nystagmus pattern. A 15-year old girl with a history of recurrent headache and oscillopsia presented with PPDN, which lasted about 12 hours and resolved spontaneously. VM should be considered in the differential diagnosis of PPDN which are presumed to be caused by the dysfunction of the vestibular cerebellum and its connection.

Spinocerebellar Ataxia Type 6 Presenting With Cervical Dystonia

A 29-year-old man presented with involuntary head turning to the right. His family history showed that his mother and two maternal uncles had dysarthria and gait disturbance. Other than mild swaying on tandem gait, his neurologic examination was normal. Brain magnetic resonance imaging demonstrated cerebellar atrophy. Molecular analysis revealed an expanded SCA6 (spinocerebellar ataxia 6) allele of 23 CAG repeats. We therefore report a case of SCA6 presenting with disabling cervical dystonia.