Diffuse brain abnormalities in myotonic dystrophy type 1 detected by 3.0 T proton magnetic resonance spectroscopy.

Patients with myotonic dystrophy type 1 (DM1) (n = 14) were compared with healthy controls (n = 13) using 3.0 T proton magnetic resonance spectroscopy ((1)H-MRS) to investigate brain pathophysiology. (1)H-MRS imaging revealed reduced N-acetylaspartate to creatine ratio (NAA/Cr) in multiple brain regions (average 24%), suggesting diffuse brain abnormalities among patients with DM1. Single-voxel (1)H-MRS among patients with DM1 showed (1) reduced NAA in both the frontal cortex (23%) and frontal white matter (31%) and unaltered myo-inositol, suggesting neuronal abnormalities without significant gliosis; and (2) elevated glutamine in the frontal cortex (36%) and reduced glutamate in the frontal white matter (20%) among patients with DM1, suggesting abnormalities in the glutamatergic system in the brain of patients with DM1. We consider that these results reflect brain abnormalities that cannot be detected by neuropathological assessment in patients with DM1.

Hypoglycemic Hemiplegia Associated with Reversible Narrowing of the Contralateral Middle Cerebral Artery in a Patient with Adrenal Insufficiency.

A 56-year-old man with a 2.5-month history of anorexia developed sweating, weakness, and left hemiplegia and hemispatial neglect. Brain magnetic resonance imaging detected no abnormalities, but magnetic resonance angiography revealed narrowing of the right middle cerebral artery (MCA). The focal neurological signs and narrowing of the MCA resolved after detection and correction of hypoglycemia. Endocrinological examinations indicated adrenal insufficiency. Hemiplegia is a rare but important neurological manifestation of hypoglycemia, although the mechanisms involved remain unknown. Combined hypoglycemia and decreased MCA blood flow associated with vasospasm probably induced regionally severe neuroglycopenia with ischemia, which presented as focal neurological symptoms.

An 81-Year-Old Man Presenting with Asthenia and Anorexia After an Alcohol-Induced Hypoglycemic Coma and a Diagnosis of Central Adrenal Insufficiency: A Case Report.

BACKGROUND Alcohol abuse inhibits the ability of the liver to release glucose into the bloodstream, primarily by inhibiting gluconeogenesis, so chronic alcohol abusers exhibit hypoglycemia after drinking alcohol without eating; this is called alcohol-induced hypoglycemia. Central adrenal insufficiency (AI) is characterized by cortisol deficiency due to a lack of adrenocorticotropic hormone. It is challenging to diagnose central AI, as it usually presents with nonspecific symptoms, such as asthenia, anorexia, and a tendency toward hypoglycemia. Here, we report a rare case of central AI that presented with AI symptoms shortly after an alcohol-induced hypoglycemic coma. CASE REPORT An 81-year-old Japanese man who had been a moderate drinker for >40 years developed a hypoglycemic coma after consuming a large amount of sake (alcohol, 80 g) without eating. After the hypoglycemia was treated with a glucose infusion, he rapidly recovered consciousness. After stopping alcohol consumption and following a balanced diet, he had normal plasma glucose levels. However, 1 week later, he developed asthenia and anorexia. The endocrinological investigation results indicated central AI. He was started on oral hydrocortisone (15 mg/day), which relieved his AI symptoms. CONCLUSIONS Cases of central AI associated with alcohol-induced hypoglycemic attacks have been reported. Our patient developed AI symptoms following an alcohol-induced hypoglycemic attack. His alcohol-induced hypoglycemic attack likely occurred in combination with a developing cortisol deficiency. This case highlights the importance of considering central AI in chronic alcohol abusers presenting with nonspecific symptoms, including asthenia and anorexia, especially when patients have previously experienced alcohol-induced hypoglycemic attacks.

Association of nitrogen compounds in drinking water with incidence of esophageal squamous cell carcinoma in Shexian, China.

The incidence of esophageal squamous cell carcinoma (ESCC), which is the eighth most common malignancy worldwide, is highest in China. The purpose of this study was to investigate the association between nitrogen compounds in drinking water with the incidence of ESCC by geographical spatial analysis. The incidence of ESCC is high in Shexian county, China, and environmental factors, particularly nitrogen-contaminated drinking water, are the main suspected risk factors. This study focuses on three nitrogen compounds in drinking water, namely, nitrates, nitrites, and ammonia, all of which are derived mainly from domestic garbage and agricultural fertilizer. The study surveyed 48 villages in the Shexian area with a total population of 54,716 (661 adults with ESCC and 54,055 non-cancer subjects). Hot-spot analysis was used to identify spatial clusters with a high incidence of ESCC and a high concentration of nitrogen compounds. Logistic regression analysis was used to detect risk factors for ESCC incidence. Most areas with high concentrations of nitrate nitrogen in drinking water had a high incidence of ESCC. Correlation analysis revealed a significant positive relationship between nitrate concentration and ESCC (P = 0.01). Logistic regression analysis also confirmed that nitrate nitrogen has a significantly higher odds ratio. The results indicate that nitrate nitrogen is associated with ESCC incidence in Shexian county. In conclusion, high concentrations of nitrate nitrogen in drinking water may be a significant risk factor for the incidence of ESCC.

Brainstem metabolites in multiple system atrophy of cerebellar type: 3.0-T magnetic resonance spectroscopy study.

BACKGROUND: The aim of this study was to find biomarkers of disease severity in multiple system atrophy of cerebellar type by imaging disease specific regions using proton magnetic resonance spectroscopy on a 3.0 T system. METHODS: We performed proton magnetic resonance spectroscopy separately in the pons and medulla on 12 multiple system atrophy of cerebellar type patients and 12 age and gender matched control subjects. The metabolite concentrations were estimated from single-voxel proton magnetic resonance spectra measured by point resolved spectroscopy, which were then correlated with clinical severity using Part I, II, and IV of the unified multiple system atrophy rating scale. RESULTS: Proton magnetic resonance spectroscopy showed that myo-inositol concentrations in both the pons and medulla were significantly higher in multiple system atrophy of cerebellar type patients compared to those of the control subjects (P < 0.05). By contrast, total N-acetylaspartate (the sum of N-acetylaspartate and N-acetylaspartylglutamate) and total choline compounds concentrations in both the pons and medulla were significantly lower in multiple system atrophy of cerebellar type patients compared to control subjects (P < 0.05). Creatine concentration in the pons was significantly higher in multiple system atrophy of cerebellar type patients compared to the control subjects (P < 0.05). Furthermore, a significant correlation was found between the myo-inositol/creatine ratio in the pons and clinical severity, defined by the sum score of unified multiple system atrophy rating scale (I+II+IV) (r = 0.76, P < 0.01). CONCLUSION: Proton magnetic resonance spectroscopy, in conjunction with a 3.0 T system, can be feasible to detect part of pathological changes in the brainstem, such as gliosis and neuronal cell loss, and the metabolites can be used as biomarkers of clinical severity in multiple system atrophy of cerebellar type patients.

A stochastic model of neuronal growth cone guidance regulated by multiple sensors.

Neuronal growth cones migrate directionally under the control of axon guidance molecules, thereby forming synapses in the developing brain. The signal transduction system by which a growth cone detects surrounding guidance molecules, analyzes the detected signals, and then determines the overall behavior remains undetermined. In this study, we describe a novel stochastic model of this behavior that utilizes multiple sensors on filopodia to respond to guidance molecules. Overall growth cone behavior is determined by using only the concentration gradients of guidance molecules in the immediate vicinity of each sensor. The detected signal at each sensor, which is treated as a vector quantity, is sent to the growth cone center and then integrated to determine axonal growth in the next step by means of a simple vector operation. We compared the results of computer simulations of axonal growth with observations of actual axonal growth from co-culture experiments using olfactory bulb and septum. The probabilistic distributions of axonal growth generated by the computer simulation were consistent with those obtained from the culture experiments, indicating that our model accurately simulates growth cone behavior. We believe that this model will be useful for elucidating the as yet unknown mechanisms responsible for axonal growth in vivo.

Serial assessments of delayed encephalopathy after carbon monoxide poisoning using magnetic resonance spectroscopy and diffusion tensor imaging on 3.0T system.

To elucidate the still unclear mechanism of delayed encephalopathy after carbon monoxide (CO) poisoning, we serially performed single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion tensor imaging (DTI) on a 3.0T system and intelligence tests in 2 patients, while they were undergoing hyperbaric oxygenation therapy. The chronological changes in (1)H-MRS- and DTI-derived parameters indicated the following: (1) White matter demyelination, aerobic metabolism inhibition, and cytotoxic edema persisted for at least 3 months even after starting the hyperbaric oxygenation therapy; (2) the axonal function and structural integrity of the white matter were initially severely impaired and then gradually and partially improved for 5 months, showing changes similar to those in the scores of the intelligence tests. The results demonstrated that brain damage after CO poisoning may persist longer than expected, and that the (1)H-MRS- and DTI-derived parameters are good indicators of the clinical progress of a patient. The combination of (1)H-MRS and DTI on a 3.0T system is useful for monitoring the changes in brain damage and the clinical symptoms of patients with delayed encephalopathy after CO poisoning.

Cost-effectiveness of the national screening program for hepatitis C virus in the general population and the high-risk groups.

In Japan, the national screening for the hepatitis C virus (HCV) has been started for both the general population and the high-risk groups. Our cost-effectiveness analysis was based on the result of the screening program including 99,001 people among the general population and 42,538 people among the high risk group from 2003 to 2006. The screening was performed using the three steps of the semi-quantitative HCV antibody test, the HCV core antigen test and the HCV-PCR test. A Markov model for HCV infected patients was constructed to estimate the future clinical benefits and the lifetime cost and the cost-effectiveness analysis was performed considering the recent treatment with peginterferon plus ribavirin. In the cost-effectiveness analysis, the cohort, in which the screening was implemented (= screening strategy), was compared with the similar cohort without the screening (= no-screening strategy) in both the general population and the high-risk group, stratified by age. The infection rates of the general population and the high-risk group were 0.36% and 0.81%, respectively. The incremental cost-effectiveness ratio (ICER), a measure of cost-effectiveness, of the general population and the high-risk group was calculated to be from 848 to 4,825 and--749 to 2,297 $/life expectancy gained, respectively. The treatment effectiveness, transition probabilities and the infection rate varied in the one-way sensitivity analyses, but the superiority of the screening strategy regarding the cost-effectiveness was unchanged. In conclusion, the screening strategy in both the general population and the high-risk group therefore appears to be more cost-effective than a no-screening strategy.

Reversible Non-parkinsonian Bradykinesia with Impaired Frontal Lobe Function as the Predominant Manifestation of Adrenal Insufficiency.

A 69-year-old Japanese man with a history of suprasellar surgery and irradiation developed bradykinesia and mild fatigue without muscle weakness, myalgia, pyramidal or extrapyramidal signs, parkinsonian symptoms, or ataxia. An endocrinological work-up revealed anterior hypopituitarism associated with secondary adrenal insufficiency. Higher brain function tests indicated an impaired frontal lobe function. The patient's bradykinesia, fatigue, and frontal lobe dysfunction improved within 2 weeks after the initiation of corticosteroid replacement therapy. To our knowledge, this is the first reported case of adrenal insufficiency manifesting as non-parkinsonian bradykinesia. Physicians should consider reversible non-parkinsonian bradykinesia associated with frontal lobe dysfunction as an unusual manifestation of adrenal insufficiency.

Daytime hypoxemia, sleep-disordered breathing, and laryngopharyngeal findings in multiple system atrophy.

BACKGROUND: The mechanism underlying nocturnal sudden death in patients with MSA remains unclear. It may be explained by upper airway obstruction, such as vocal cord abductor paralysis; an impairment of the respiratory center, such as Cheyne-Stokes respiration; or an impaired hypoxemic ventilatory response. OBJECTIVE: To investigate the mechanism of sleep-disordered breathing in multiple system atrophy (MSA). DESIGN: We recruited 21 patients with probable MSA who were admitted sequentially to our hospital, and performed daytime blood gas analysis, pulmonary function tests, polysomnography, and fiberoptic laryngoscopy during wakefulness and with the patient under anesthesia. RESULTS: A decrease in arterial oxygen pressure and an increase in alveolar-arterial oxygen gradient significantly correlated with disease duration (P = .045 and .046, respectively). Polysomnography demonstrated Cheyne-Stokes respiration in 3 (15%) of 20 patients. Fiberoptic laryngoscopy during wakefulness showed that 3 (14%) of the 21 patients exhibited vocal cord abductor paralysis, and laryngoscopy under anesthesia showed that 9 (45%) of 20 patients exhibited vocal cord abductor paralysis. Laryngoscopy under anesthesia also revealed that 11 (55%) of 20 patients showed upper airway obstruction in places other than the vocal cords, including obstruction at the base of the tongue or soft palate. In addition, it demonstrated novel laryngopharyngeal findings, such as floppy epiglottis and airway obstruction at the arytenoid. CONCLUSIONS: We observed daytime hypoxemia with an increased alveolar-arterial oxygen gradient, Cheyne-Stokes respiration, and novel abnormal laryngopharyngeal movements in patients with MSA. We also found that laryngoscopy under anesthesia might be useful for evaluating upper airway obstruction. The significance of these findings to the mechanism of sudden death in those with MSA needs to be examined.

Multiplex families with multiple system atrophy.

BACKGROUND: Multiple system atrophy (MSA) has been considered a sporadic disease, without patterns of inheritance. OBJECTIVE: To describe the clinical features of 4 multiplex families with MSA, including clinical genetic aspects. DESIGN: Clinical and genetic study. SETTING: Four departments of neurology in Japan. Patients Eight patients in 4 families with parkinsonism, cerebellar ataxia, and autonomic failure with age at onset ranging from 58 to 72 years. Two siblings in each family were affected with these conditions. MAIN OUTCOME MEASURES: Clinical evaluation was performed according to criteria by Gilman et al. Trinucleotide repeat expansion in the responsible genes for the spinocerebellar ataxia (SCA) series and for dentatorubral-pallidoluysian atrophy (DRPLA) was evaluated by polymerase chain reaction. Direct sequence analysis of coding regions in the alpha-synuclein gene was performed. RESULTS: Consanguineous marriage was observed in 1 of 4 families. Among 8 patients, 1 had definite MSA, 5 had probable MSA, and 2 had possible MSA. The most frequent phenotype was MSA with predominant parkinsonism, observed in 5 patients. Six patients showed pontine atrophy with cross sign or slitlike signal change at the posterolateral putaminal margin or both on brain magnetic resonance imaging. Possibilities of hereditary ataxias, including SCA1 (ataxin 1, ATXN1), SCA2 (ATXN2), Machado-Joseph disease/SCA3 (ATXN1), SCA6 (ATXN1), SCA7 (ATXN7), SCA12 (protein phosphatase 2, regulatory subunit B, beta isoform; PP2R2B), SCA17 (TATA box binding protein, TBP) and DRPLA (atrophin 1; ATN1), were excluded, and no mutations in the alpha-synuclein gene were found. CONCLUSIONS: Findings in these multiplex families suggest the presence of familial MSA with autosomal recessive inheritance and a genetic predisposition to MSA. Molecular genetic approaches focusing on familial MSA are expected to provide clues to the pathogenesis of MSA.

Visualization of the Intimal Flap in Intracranial Arterial Dissection Using High-Resolution 3T MRI.

BACKGROUND AND PURPOSE: Presence of an intimal flap is a critical imaging finding in diagnosing intracranial artery dissection (ICAD). Recent reports showed that high-resolution magnetic resonance imaging (MRI) was better at identifying intimal flaps as compared with routine MRI techniques used in clinical settings. However, no current standardized sequence for high-resolution MRI without gadolinium enhancement produces images of satisfactory quality with clinically tolerable scanning times. This study evaluated a nonenhanced high-resolution fast spin echo (HR-FSE) MRI sequence for visualizing intimal flaps in patients with ICAD. SUBJECTS AND METHODS: Three patients with ICAD underwent plain MRI examination using a 2-dimensional T2-weighted FSE imaging sequence optimized for our 3T system (in-plane pixel size, .23 mm × .23 mm; slice thickness 3 mm with no interslice gap), as well as scanning with conventional modalities, including CT angiography, magnetic resonance angiography, and digital subtraction angiography. We assessed whether these imaging methods could visualize an intimal flap and/or double lumen sign in the participants and compared the results between HR-FSE and the other modalities. RESULTS: HR-FSE images clearly showed intimal flaps and double lumen signs in all 3 patients, whereas the conventional modalities identified a double lumen sign in only 2 of the 3 patients. CONCLUSIONS: The present method of optimized HR-FSE imaging with a 3T system improved visualization of intimal flaps and should thus be considered for assessing patients with suspected ICAD that cannot be definitively diagnosed by conventional imaging modalities.

Generalized Status Epilepticus in a Patient with Acute-onset Type 1 Diabetes Mellitus Associated with Severe Kidney Dysfunction: A Case Report and Literature Review.

A 65-year-old Japanese man with advanced chronic kidney disease (CKD) developed acute-onset type 1 diabetes mellitus (T1D) that was associated with severe acute kidney injury and was manifested by generalized tonic-clonic status epilepticus. His seizures resolved without recurrence after correcting the diabetic ketoacidosis. Although hyperglycemia is an important cause of acute symptomatic seizure (ASS), patients with ketotic hyperglycemia develop ASS less frequently. In this T1D case with CKD, severe hyperglycemia in conjunction with other metabolic insults, such as uremia, hyponatremia, and hypocalcemia, probably provoked his seizure despite the severe ketonemia.

[Posttraumatic hyperkinésie volitionnelle was markedly improved by Vim thalamic deep brain stimulation].

A 69-year-old man presented with hyperkinésie volitionnelle (HV) one year after a brain injury. We considered diffuse axonal injury (DAI) as the cause of HV in this patient. Neither three-dimensional anisotropy contrast magnetic resonance axonography (3DAC-MRX) nor movement-related cortical potential (MRCP) measurements revealed any abnormal findings. These suggest that the cerebellar efferent pathways were intact. Vim deep brain stimulation (DBS) markedly improved HV, which was resistant to clonazepam. This study demonstrated that traumatic brain injury can cause the tremor type of HV even when the cerebellar efferent pathways are intact, and that Vim DBS is an alternative treatment for HV that is unresponsive to drugs.

[A patient with HIV encephalopathy presenting with parkinsonism during HAART therapy].

We report the case of a 32-year-old man presenting symptoms of parkinsonism. Neurological examination revealed parkinsonism symptoms such as akinesia and postural instability, dementia and frontal lobe signs. He was diagnosed as having human immunodeficiency virus (HIV) encephalopathy. Brain MRI, 99mTc ECD-SPECT and 1H-MR spectroscopy demonstrated symmetrical cerebral white matter lesions, predominantly in the bilateral frontal lobes. Frontal lobe dysfunction could be responsible for his parkinsonism associated with HIV encephalopathy. His neurological symptoms improved transiently after the initiation of HAART but fluctuated when antiretroviral drugs were changed because of their side effects. Although HAART effectively decreased plasma HIV-RNA load and increased peripheral blood CD4 cell count, his parkinsonism and dementia eventually exacerbated. Our results suggest that a combination of antiretroviral drugs affects the therapeutic efficacy against HIV encephalopathy, and that CNS symptoms could be aggravated during HAART, even when plasma HIV-RNA load and CD4 cell count are maintained under favorable conditions.

Laryngeal stridor in multiple system atrophy: Clinicopathological features and causal hypotheses.

Laryngeal stridor is recognized as a characteristic clinical manifestation in patients with multiple system atrophy (MSA). However, the pathogenic mechanisms underlying this symptom are controversial. Neurogenic atrophy of the posterior cricoarytenoid muscle has been identified in cases of MSA, suggesting that laryngeal abductor weakness contributes to laryngeal stridor. However, dystonia in the laryngeal adductor muscles has also been reported to cause laryngeal stridor. Depletion of serotonergic neurons in the medullary raphe nuclei, which exert tonic drive to activate the posterior cricoarytenoid muscle, has recently been identified in MSA cases. This adds weight to the possibility that laryngeal abductor weakness underlies laryngeal stridor in MSA. Continuous positive airway pressure therapy is currently used in the treatment of laryngeal stridor, but should be used with caution in patients showing contraindications. Current knowledge of the clinical and neuropathological features of laryngeal stridor is summarized in this paper, and the hypothesized causes and possible therapeutic options for this symptom are discussed.

Apparent diffusion coefficients distinguish amyotrophic lateral sclerosis from cervical spondylotic myelopathy.

OBJECTIVE: Fifty percent of patients with amyotrophic lateral sclerosis (ALS) have cervical spondylotic myelopathy (CSM) as a complication. Because patients with ALS do not develop bulbar signs and symptoms at onset, differentiating them from patients with CSM is sometimes difficult. We aimed to determine whether the apparent diffusion coefficients (ADCs) of intracranial corticospinal tracts can be used to distinguish between patients with ALS and those with CSM. METHODS: We evaluated 19 consecutive patients with ALS who did not have CSM by cervical MRI, 16 patients with CSM, and 11 healthy controls. We examined the mean ADCs in the precentral gyrus, the corona radiata, the posterior limbs of the internal capsule (PLIC), and the cerebral peduncle by 3T magnetic resonance imaging (MRI). The mean ADCs in the intracranial corticospinal tracts in patients with ALS were compared with those in patients with CSM. RESULTS: The mean ADCs in the intracranial corticospinal tracts in patients with ALS were compared with those in patients with CSM (p<0.05). Additionally, the mean ADCs in the precentral gyrus, the PLIC, and the cerebral peduncle in the patients with ALS, including the patients who were initially diagnosed as having clinically possible ALS on the basis of the revised El Escorial criteria and did not develop bulbar symptoms at onset, were also higher than those in patients with CSM (p<0.05). CONCLUSIONS: Elevated ADCs in the intracranial corticospinal tracts might be useful for distinguishing ALS from CSM in the early stage of the disease.

EZ-tracing: a new ready-to-use algorithm for magnetic resonance tractography.

A new algorithm for tractography based on diffusion tensor analysis (DTA) is presented. This method, called EZ-tracing, is based on a new algorithm for analyzing DTA data, lambda chart analysis (LCA), and effectively overcomes the main shortcomings of previous methods for tractography. EZ-tracing is written in MATLAB scripting language (MathWorks, Natick, MA, USA) and can be implemented on any of the common operating systems, such as Microsoft Windows, UNIX, and LINUX. The program is available in public at coe@bri.niigata-u.ac.jp.

Quantitative evaluation of brainstem involvement in multiple system atrophy by diffusion-weighted MR imaging.

In multiple system atrophy (MSA), symptoms associated with dysfunctions of the brainstem and autonomic nervous system are important prognostic factors. We investigated brainstem involvement in 12 patients with MSA with predominant cerebellar symptoms (MSA-C) (mean age, 56.3 +/- 9.9 years, median disease duration, 3 years), and 11 controls (57.6 +/- 12.0 years) matched for age using diffusion-weighted MR imaging (DWI). We demonstrated that apparent diffusion coefficients (ADCs) in the pons and middle cerebellar peduncle of MSA-C patients are significantly higher than those of normal controls even though the patients are in the early stage of the disease. Furthermore, we demonstrated that increased ADC values correlated well with the disease duration. The current study demonstrated that DWI is a useful noninvasive method for the quantitative evaluation of the brainstem involvement in MSA-C patients.