Long Spontaneous Remission in Neuromyelitis Optica

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system characterized by optic neuritis and longitudinal extensive transverse myelitis. The clinical course can be either polyphasic (relapsing-remitting) or monophasic. The relapsing-remitting course is observed in more than 80% of NMO cases, and relapse generally occurs within 1 year in 60% of patients, and within 3 years in 90%. We report a rare case of long spontaneous remission in untreated NMO.

Brachial Plexopathy Caused by Vertebral Artery Dissection

No abstract available.

Neuroleptic Malignant Syndrome Caused by Long Term Intake of Haloperidol

Neuroleptic malignant syndrome (NMS) is a fatal complication most often caused by an adverse reaction to neuroleptic or antipsychotic drugs, and is mostly brought out in the initial stage of medication. Late onset NMS after long term intake of neuroleptics is uncommon, and the neurochemical mechanism is undiscovered. We report a patient of late onset NMS after a long term intake of haloperidol who was successfully treated with dantrolene and bromocriptine.

Transcranial Doppler Sonography in Acute Ischemic Stroke

The acute stage of an ischemic stroke shows various hemodynamic changes of the involved intracranial arteries. Transcranial Doppler sonography (TCD) is known to be the only tool that can monitor the hemodynamic changes and microembolic signals in the intracranial artery in real-time after an ischemic stroke. Findings of TCD during systemic thrombolytics could inform us of a recanalization of the occluded vessel and the need for further intervention. It has been accepted that ultrasounds have thrombolytic effect on clots when it is used with systemic thrombolytics although the standard protocol and the evidence for its safety are still lacking until now. In this article, we review current utilities of TCD for the management of acute ischemic strokes.

Gene-to-Gene Interaction between Sodium Channel-Related Genes in Determining the Risk of Antiepileptic Drug Resistance

The pathogenesis of antiepileptic drug (AED) resistance is multifactorial. However, most candidate gene association studies typically assess the effects of candidate genes independently of each other, which is partly because of the limitations of the parametric-statistical methods for detecting the gene-to-gene interactions. A total of 200 patients with drug-resistant epilepsy and 200 patients with drug-responsive epilepsy were genotyped for 3 representative the single nucleotide polymorphisms (SNPs) of the voltage-gated sodium channel genes (SCN1A, SCN1B, and SCN2A) by polymerase chain reaction and direct sequencing analysis. Besides the typical parametric statistical method, a new statistical method (multifactor dimensionality reduction [MDR]) was used to determine whether gene-to-gene interactions increase the risk of AED resistance. None of the individual genotypes or alleles tested in the present study showed a significant association with AED resistance, regardless of their theoretical functional value. With the MDR method, of three possible 2-locus genotype combinations, the combination of SCN2A-PM with SCN1B-PM was the best model for predicting susceptibility to AED resistance, with a p value of 0.0547. MDR, as an analysis paradigm for investigating multi-locus effects in complex disorders, may be a useful statistical method for determining the role of gene-to-gene interactions in the pathogenesis of AED resistance.

Predisposition of genetic disease by modestly decreased expression of GCH1 mutant allele

Recently it was shown that single nucleotide polymorphisms (SNPs) can explain individual variation because of the small changes of the gene expression level and that the 50% decreased expression of an allele might even lead to predisposition to cancer. In this study, we found that a decreased expression of an allele might cause predisposition to genetic disease. Dopa responsive dystonia (DRD) is a dominant disease caused by mutations in GCH1 gene. The sequence analysis of the GCH1 in a patient with typical DRD symptoms revealed two novel missense mutations instead of a single dominant mutation. Family members with either of the mutations did not have any symptoms of DRD. The expression level of a R198W mutant allele decreased to about 50%, suggesting that modestly decreased expression caused by an SNP should lead to predisposition of a genetic disease in susceptible individuals.

Symptomatic Intracranial Hemorrhage after Thrombolytic Therapy at the Site of a Prior Microbleed, Contralateral to the Acute Ischemic Field

No abstract available.

Flow Diversion on TCD in Symptomatic MCA Steno-Occlusive Disorder: Evidence of Leptomeningeal Collateral Circulation

BACKGROUND: To investigate the clinical significance of flow diversion (FD) of the anterior cerebral artery (ACA) or posterior cerebral artery (PCA), a transcranial doppler (TCD) was used in patients with middle cerebral artery (MCA) occlusive disorders. METHODS: This is a retrospective study of 51 patients from 1999 to 2001. FD was determined using TCD. Leptomeningeal collateral channels (LMCs) were identified by conventional angiography. The author analyzed the sensitivity, specificity, positive and negative predictability of FD of ACA or PCA to predict the LMCs, and also evaluated the relationship between FD and leptomeningeal collateral circulation. RESULTS: LMC was noted in 41% of patients with M1 (MCA) occlusive disorders. It showed a tendency of increasing prevalence with an increasing degree of M1 MCA stenosis (rho=0.605, p<0.001). FD was noted in 47% of patients with MCA occlusive diseases. It also had a tendency of high prevalence with an increasing degree of M1 MCA stenosis (rho=0.382, p=0.006). To predict the presence of LMCs, FD of ACA or PCA had a sensitivity of 81%, specificity of 76%, positive predictive value of 71% and negative predictive value of 85%. FD of ACA or PCA had a good correlation with LMCs in patients with MCA occlusive disorders (rho=0.568, p<0.001). CONCLUSIONS: These results suggest that FD had good sensitivity and specificity to predict the LMCs, and demonstrated that FD was a reliable source of evidence of LMCs in patients with M1 MCA occlusive disorders. Patients with M1 MCA stenosis had heterogeneous hemodynamics in the development of collateral circulation.

A Case of Intradural, Extramedullary Tuberculous Granuloma Developed During the Treatment of Tuberculous Meningitis

A 24-year-old man was treated with anti-tuberculous therapy after being diagnosed with tuberculous meningitis. However, he developed abrupt onset of weakness in the lower extremities. Thoracic spinal magnetic resonance imaging (MRI) showed a soft tissue mass, a compressed posterior spinal cord. A total resection of the intradural extramedullary mass was performed. A histological examination revealed the infiltration of inflammatory cells with granulomatous lesions. Intradural extramedullary tuberculous granuloma is rare, but must be considered in the differential diagnosis of spinal cord compression.

Hypervolemic Versus Normovolemic Therapy in Patients with Ruptured Cerebral Aneurysm

BACKGROUND: Postoperative triple H therapy is regarded as a mainstay for prophylaxis and treatment of delayed ischemic neurologic deficit (DIND) after subarachnoid hemorrhage (SAH). However, there are doubts about its effectiveness. This study was performed to assess hypervolemic dynamic fluid therapy in patients with ruptured cerebral aneurysms. METHODS: The authors retrospectively studied a total of 393 patients with ruptured cerebral aneurysms, consisting of early surgery with or without intraoperative ventriculostomy during a recent 5 year period (July 1998~June 2003). Hypervolemic dynamic fluid therapy was initiated postoperatively in patients with DIND. Since January 2001, however, patients were maintained in normovolemia and normotension, and when DIND had manifested, low molecular weight dextran was only added. The incidence of DIND and outcome according to Glasgow Outcome Scale at 6 months of the normovolemic group were compared with the hypervolemic group. All patients were followed for at least 14 days after the admission including clinical assessment, TCD recording, CT scanning, CVP measurements, and nimodipine infusion. RESULTS: Subjects in the two treatment groups were similar with regard to age, sex, Fisher grade, Hunt-Hess grade, aneurysm location, and aneurysm size. No differences were found between the two groups regarding the incidence of DIND (29/182: 15.9% vs 29/211: 13.7%). Surgical outcome in the normovolemic group (good, 171/211: 81.0%) was comparable to the hypervolemic group (good, 154/182: 84.6%). CONCLUSIONS: Although careful fluid management to avoid hypovolemia may reduce the risk of DIND after SAH, prophylactic hypervolemic dynamic fluid therapy is unlikely to confer an additional benefit.

Acute Sensory Neuropathy Associated with anti-GD1b Ig G Antibody

Acute sensory neuropathy (ASN) is rare and is characterized by acute onset of sensory ataxia, loss of deep tendon reflexes and impaired vibratory and joint position sensations. Similar to Guillain-Barre syndrome (GBS) with prominent sensory ataxia, a few cases of ASN associated with antiganglioside antibodies have been reported. This suggests that a common autoimmue mechanism operates in some cases of ASN and of GBS with sensory ataxia. We report a patient with ASN associated with anti-GD1b IgG antibody.

Expression of Phosphorylated ERK1/2 and cFos Proteins in Vestibular Nuclei by Selective Stimulation of Horizontal Semicircular Canal

BACKGROUND: There is a little information about the effect of selective vestibular stimulation on the expression of activity-dependent metabolic markers in the vestibular nuclei. The purpose of this study was to evaluate effect of afferent excitation of the horizontal semicircular canal on expression of phosphorylated ERK1/2 (pERK1/2) and cFos proteins in the vestibular nuclei. METHODS: The horizontal semicircular canal of Sprague-Dawley rats was selectively stimulated by using the sinusoidal horizontal stimulator with 10-minute duration of stimulation. Conventional immunohistochemical method was used to visualize pERK1/2 or cFos immunoreactive neurons in the vestibular nuclei following rotation. RESULTS: Five minutes after stimulation of the horizontal semicircular canal there was a high expression of pERK1/2 protein in the medial vestibular nucleus among 4 major subnuclei of the central vestibular nuclear complex. On the contrary, immunoreactivity of cFos protein was observed in the medial and inferior vestibular nucleus 2 hours after horizontal sinusoidal rotation. The lateral vestibular nucleus was free from the expression of pERK1/2 and cFos proteins in response to excitation of the horizontal semicircular canal. However, in the vestibular nuclei of unilaterally labyrinthectomized rats expression of pERK and cFos proteins was markedly suppressed in ipsi-lesional side as well as contra-lesional side following stimulation of the horizontal semicircular canal. Furthermore no expression of pERK1/2 and cFos protein in the bilateral vestibular nuclei of bilaterally labyrinthectomized rats was noted after stimulation of the horizontal semicircular canal. CONCLUSIONS: Therefore these results of present study suggest that excitatory afferent signals from the peripheral vestibular receptors are essential for protein translation for pERK1/2 and cFos in response to stimulation of the semicircular canal.

Transcranial Doppler Examination Following EIAB in Patients with Hemodynamic Cerebral Ischemia

OBJECTIVE: The aim of this study is to evaluate the effects of intracranial-extracranial arterial bypass(EIAB) surgery on cerebrovascular reserve capacity(CRC) in patients with hemodynamic cerebral ischemia and to assess the significance of transcranial doppler(TCD) examination before and after EIAB surgery. METHODS: In 29 consecutive patients who underwent EIAB surgery due to symptomatic internal carotid artery or middle cerebral artery(MCA) occlusion, 21 patients were studied using preoperative and postoperative digital subtraction angiogram(DSA), SPECT, and TCD examination. After measuring mean radioactivity count of a region of interest, relative regional cerebral blood flow(rrCBF) was quantitated by the following formula: lesional radioactivity count/contralateral radioactivity count x 100%. CRC was calculated as the percentage change from baseline flow after a vasodilatory challenge. RESULTS: Postoperative DSA showed good collateral circulation through the bypass except 4 patients. Preoperative mean value of rCRC improved significantly after EIAB surgery from -14.8+/-2.6% to 6.9+/-2.7%(p<0.01). Intraoperatively, flow velocity of superficial temporal artery(STA) and MCA just after anastomoses increased remarkably in comparison with the values just before anastomoses(p<0.01). There was no correlation between the change of pre- and postoperative flow velocity and the change of rrCBF. In patients with the increase of flow velocity after surgery manifested good collateral circulation through the bypass. The difference was statistically significant(repeated measures ANOVA, p<0.05). Over a mean follow-up period of almost 3 years, no patient had another episode of brain ischemia. CONCLUSION: We believe that the measurement of flow velocity is expected a good method to evaluate the degree of collateral circulation through the bypass.

Expression of Immediate-Early Gene Proteins by Transient Occlusion of Anterior Inferior Cerebellar Artery in Vestibular Nuclei of Sprague-Dawley Rats

BACKGROUND: Anterior cerebellar artery (AICA) occlusion results in vestibular dysfunctions because the AICA supplies the vestibular nuclei (VN) in the brain stem as well as the peripheral vestibular organs in the inner ear. The purpose of this study was to evaluate the expression of immediate-early gene products, a metabolic marker of neural excitation in neurons, by AICA occlusion in the VN of Sprague-Dawley rats. METHODS: After chloral hydrate anesthesia all animals were subjected to unilateral AICA occlusion by using a microsurgical clamp for 30 min to induce a transient ischemia. Unilateral labyrinthectomy was chemically undertaken to eliminate vestibular afferent activity. Immunohistochemical staining and image analysis for cFos, FosB, Krox-24, and JunB proteins were performed 2 hours after AICA occlusion. RESULTS: There was a high expression of cFos protein in the bilateral medial and inferior VN 2 hours after AICA occlusion. AICA occlusion induced minimal changes in cFos protein expression in the lateral and superior VN. Mild to moderate expressions of FosB and JunB protein in VN was observed 2 hours after ischemic injury of the brain stem and inner ear. On the contrary, the number of cFos and FosB immunoreactive neurons significantly decreased in the medial vestibular nucleus ipsilateral to the injured labyrinth 2 hours after AICA occlusion in the UL group. CONCLUSIONS: These results suggest that ischemic afferent activity from the peripheral vestibular apparatus is essential for the expression of immediate-early gene products in the medial and inferior VN of rats following AICA occlusion.

Relationships of Apolipoprotein E Genotypes with Vascular Risk Factors in Patients with Alzheimer's Disease

BACKGROUND: Apolipoprotein E-epsilon4 (APOE-epsilon4) is a known genetic risk factor for Alzheimer's disease (AD), but its relationship with vascular risk factors is still controversial. METHODS: We retrospectively studied 56 probable AD patients diagnosed by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorder's Association (NINCDS-ADRDA) criteria. RESULTS: The frequencies of APOE-epsilon2, 3, and 4 were 6.3%, 69.6%, and 24.1% in patients with AD. Compared to the no APOE-epsilon4 group (n=35), the APOE-epsilon4 group (n=21) revealed a higher frequency of male gender with no difference in age, educational level, dementia onset age, severity of dementia (CDR and K-MMSE), the frequencies of vascular risk factors (hypertension, diabetes, hypercholesterolemia), and total cholesterol level. High density lipoprotein (HDL)-cholesterol level was 36+/- 8 in the APOE-epsilon4 group and 43+/-11 in the no APOE-epsilon4 group with statistical significance (Student's t-test, p=0.02). In adjusting for sex, the APOE-epsilon4 group still had a significantly lower HDL-cholesterol level than the no APOE-epsilon4 group (p=0.047). CONCLUSIONS: These results suggest that there may be the genetic influence of APOE-epsilon4 on serum HDLcholesterol metabolism in AD patients.

Changes in Vestibular Nerve Activity Following Acute Hypotension in Rats

The basic mechanism for the excitation of the peripheral vestibular receptors following acute hypotension induced by sodium nitroprusside (SNP) or hemorrhage was investigated in anesthetized rats. Electrical activity of the afferent vestibular nerve was measured after pretreatment with kynurenic acid, an NMDA receptor antagonist. The activity of the vestibular nerve at rest following acute hypotension induced by SNP or simulating hemorrhage was a greater increase than in control animals. The gain of the vestibular nerve with sinusoidal rotation following acute hypotension increased significantly compared to control animals. The acute hypotension induced by SNP or hemorrhage did not change the activity of the afferent vestibular nerve after kynurenic acid injection. These results suggest that acute hypotension produced excitation of the vestibular hair cells via glutamate excitotoxicity in response to ischemia.

A Case of Extrapontine Myelinolysis with both Frontal Lobe Dysfunction and Decreased Perfusion in SPECT

A thirty-nine year old woman was consulted because of personality change, agitation and memory disturbance. She received chemotherapy and oral steroids because of carcinoma within the bronchus. She had a high serum osmolarity caused by hyperglycemia and hypernatremia, and it was corrected rapidly. Her brain MRI showed EPM (extrapontine myelinolysis). Brain SPECT showed hypoperfusion in the bilateral orbitofrontal regions. We report a patient with EPM with typical frontal lobe dysfunction as an initial manifestation and bilateral orbitofrontal hypoperfusion.

Effect of Extracranial-Intracranial Bypass on Cerebral Blood Flow and Vasomotor Reactivity in patients with Compromised Cerebral Hemodynamics

BACKGROUND: The obstruction of intracranial arteries causes cerebral hemodynamic impairment. It is now evident that patients with cerebral hemodynamic compromise have a higher risk of stroke than those with normal cerebral blood flow. The purpose of this study is to investigate the changes of cerebral blood flow and vascular reactivity after extra-intracranial arterial bypass (EIAB) surgery in patients with cerebral hemodynamic compromise. METHODS: We enrolled 16 consecutive patients (8 female and 8 male patients) with transient ischemic attack or cerebral infarction resulted from the occlusion of distal internal carotid artery (ICA) or middle cerebral artery (MCA). We measured the relative regional cerebral blood flow (rrCBF) at rest and after Diamox infusion, and vasomotor reactivity by using single photon emission computed tomography (SPECT). We performed extra-intracranial arterial bypass (EIAB) surgery in patients with impaired vasomotor reactivity. Follow-up brain SPECT was done at 3months after EIAB. We compared the rrCBF and vasomotor reactivity before and after EIAB, and evaluated the effect of collateral vessels on the cerebral hemodynamic after surgery. RESULTS: EIAB increases the vasomotor reactivity significantly (-19.6+/-10 before EIAB, 11.2+/-27 after EIAB, p=0.003) but does not increase the cerebral blood flow at rest (70.5% before EIAB, 70.9% after EIAB). The degree of collateral vessel development did not influence on the restoration of vasomotor reactivity. CONCLUSIONS: These results demonstrate that EIAB increases the vasomotor reactivity of the distal part on the occluded ICA or MCA, but does not increase the cerebral blood flow at rest.

Analysis of Role of Peripheral Vestibular Receptors on Orthostatic Tolerance using Heart Rate Variability in Rats

BACKGROUND: There is substantial evidence that the vestibular system is involved in the regulation of blood pressure. Heart rate variability (HRV) is useful to investigate the role of the peripheral vestibular receptors and the baroreceptors in the orthostatic tolerance. METHODS: EKG was recorded during postural changes with the head up either after sinoaortic denervation or after bilateral labyrinthectomies in Sprague-Dawley rats. HRV, including mean, standard deviation, coefficient of variation (CV), and power spectrum, were analyzed from R-R intervals of EKG. RESULTS: Phenylephrine increased low frequency region and sodium nitroprusside increased high frequency region in the power spectral analysis of HRV in anesthetized rats. Postural changes decreased blood pressure transiently and then increased blood pressure gradually in control rats, but the depression of blood pressure induced by postural change was greater in rats with both sinoaortic denervation and bilateral labyrinthectomies. The increase of CV of HRV just after sinoaortic denervation or bilateral labyrinthectomies represents an unstable heart rate in resting position, however, CV of HRV was increased markedly by postural change 7 days after bilateral labyrinthectomies. Postural change with sinoaortic denervation increased low-frequency region representing sympathetic activity, whereas bilateral labyrinthectomies increased highfrequency region representing parasympathetic activity in power spectral analysis. CONCLUSIONS: These results suggest that both the peripheral vestibular receptors and the baroreceptors have subsidiary action in orthostatic tolerance and the peripheral vestibular receptors regulate blood pressure during postural change through the sympathetic nervous system.

Deep Cerebral Venous Thrombosis Showing Parkinsonism such as Micrographia, Hypophonia and Bradykinesia

Deep cerebral venous thrombosis is a rare condition associated with edema, infarction or hemorrhage in basal ganglia, thalamus and periventricular white matter. It presents nonspecific clinical manifestations such as altered consciousness, headache, focal neurological deficit, nausea and vomiting. Extrapyramidal signs are very rare in deep cerebral venous thrombosis. We report a patient who presented micrographia, hypophonia and bradykinesia as an early manifestation of deep cerebral venous thrombosis.