Yoshimasa Sueda

Detection of cervical nerve root hypertrophy by ultrasonography in chronic inflammatory demyelinating polyradiculoneuropathy

Several studies have demonstrated abnormal MRI findings in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), especially hypertrophy and abnormal enhancement of spinal nerve roots, but there have been few reports on ultrasonographic findings of spinal nerve roots in CIDP. To determine whether ultrasonography (US) enables detection of hypertrophy of the cervical nerve roots, how frequently hypertrophy occurs in CIDP, and whether US findings correlate with any clinical and laboratory features, US of cervical nerve roots was performed using a 7.5-MHz linear-array transducer in 13 CIDP patients and 35 control subjects. A coronal oblique plane with a transducer placed on the lateral side of the neck was used to visualize the cervical nerve roots just after their point of exit from the cervical foramina, and their diameters were measured. US demonstrated hypertrophy of the cervical nerve roots in 9 (69%) of the 13 CIDP patients as compared with findings in control subjects. The degree of hypertrophy was significantly associated with the level of CSF protein (chi2=5.8, p<0.05, logistic simple regression analysis) but not with other clinical features. US is considered to be a useful method for evaluating cervical nerve root hypertrophy, which is frequently seen in patients with CIDP, particularly in patients with elevated level of CSF protein.

Cancer‐associated ischemic stroke is associated with elevated d‐dimer and fibrin degradation product levels in acute ischemic stroke with advanced cancer

Aim:  Although several studies have reported various causes of ischemic stroke in patients with cancer, only a few have evaluated the clinical relevance of ischemic stroke pathogenesis to cancer. The aim of the present study was to elucidate the clinical characteristics of cancer‐associated ischemic stroke.

Therapeutic effects of postischemic treatment with hypotensive doses of an angiotensin II receptor blocker on transient focal cerebral ischemia.

Background Neurovascular protection against cerebral ischemia is not consistently observed with a postischemia hypotensive dose of candesartan. The aim of this study was to determine the levels of brain angiotensin II after reperfusion and the efficacy and therapeutic time window of postischemic treatments with hypotensive doses of candesartan for the treatment of cerebral ischemia. Method Occlusions of the right middle cerebral artery (60 min) followed by reperfusion were performed using the thread method under halothane anesthesia in Sprague–Dawley (SD) rats. Protein levels of brain angiotensin II and mRNA levels of renin–angiotensin system components were evaluated following reperfusion (n=184 in total). Low-dose or high-dose treatments with candesartan cilexetil (1 or 10 mg/kg per day, respectively) were administered orally immediately following reperfusion once daily for 4 or 7 days (n = 119 in total). An additional group was treated with low-dose candesartan cilexetil after a 12-h delay based on the brain angiotensin II levels (n = 14). Results Levels of brain angiotensin II transiently increased 4–12 h after reperfusion, which followed an increase in angiotensinogen mRNA. Candesartan cilexetil treatments significantly reduced blood pressure (BP) in rats administered the high dose and moderately in rats receiving the low dose. A low dose of candesartan cilexetil reduced the infarct size, cerebral edema, and neurological deficits, whereas the high-dose treatments showed limited reductions. Furthermore, oxidative stress following reperfusion was reduced with the low-dose treatments. The therapeutic time window was open for at least 12 h after reperfusion when brain angiotensin II levels had peaked. Conclusion Postischemic treatments using low hypotensive doses of candesartan cilexetil provided protection against cerebral ischemic injury and may have a clinically relevant therapeutic time window.

Effects of Meteorological Conditions on the Risk of Ischemic Stroke Events in Patients Treated with Alteplase—HEWS-tPA

BACKGROUND Predicting a day that presents a high risk for the occurrence of ischemic stroke events may enable health professionals to prepare for emergency stroke therapy more properly. We evaluated the association between meteorological conditions and the frequency of ischemic stroke events in Japanese patients. METHODS Ischemic stroke patients (n = 299) who were treated with alteplase at 9 stroke hospitals in 3 restricted areas were examined. The daily rates of ischemic stroke events were compared with the daily mean thermo-hydrological index (THI), the atmospheric pressure, and the daily changes of these variables for the 6 days preceding an ischemic stroke event using Poisson regression analysis. RESULTS We trisected onset days based on the THI (low-temperature, intermediate-temperature, and high-temperature), atmospheric pressure (low-pressure, intermediate-pressure, and high-pressure), changes in THI for preceding 6 days from the previous day (cooler, unchanged-temperature, and warmer), and changes in atmospheric pressure (decreased-pressure, unchanged-pressure, and increased-pressure). The frequency of ischemic stroke was significantly higher on low-temperature or high-pressure days (risk ratio, 1.398, P = .022; risk ratio, 1.374, P = .039), on warmer-temperature days, and when atmospheric pressure varied from the day before (P < .05). There were significantly lower risks for ischemic stroke events on cooler-temperature days, and higher risks were associated with a variation in atmospheric pressure 3 days before the onset from 4 days before (P < .05). CONCLUSIONS There were higher risks for ischemic stroke events associated with low ambient temperature, high atmospheric pressure, increased temperature, and varied atmospheric pressure. Also, atmospheric pressure variation 3 days before may be associated.

The Association between Hyperintense Vessel Sign and Final Ischemic Lesion Differ in Its Location

BACKGROUND The hyperintense vessel sign (HVS) on fluid-attenuated inversion recovery images can frequently be detected in patients with acute cerebral infarction attributable to large artery stenosis or occlusion. The prognostic values and clinical characteristics of HVS remain to be elucidated. The aim of this study was to evaluate the association of HVS with ischemic lesions and severity of neurologic deficit. METHODS A total of 96 consecutive acute ischemic stroke patients (54 women, median age 76.5 [range 39-97] years), who had symptomatic severe stenosis or occlusion in the proximal middle cerebral artery that was detected with magnetic resonance angiography within 24 hours of onset, were enrolled. The extent of HVS was graded by a systematic quantitative scoring system (the HVS distribution score) based on Alberta Stroke Program Early Computed Tomographic Score. RESULTS An HVS was detected in 89 patients (93%) at admission, and the patients who displayed wider HVS distribution scores exhibited more severe neurologic deficits at admission (P<.05). The follow-up magnetic resonance imaging, which was obtained in 79 patients (82%), was performed an average of 13 days. The association between HVS distribution score and final ischemic lesions was strongly observed (n=67, P<.05) but not in the patients with intravenous thrombolysis (n=12, P=.06). CONCLUSIONS Although the distribution of HVS reflected final ischemic lesion, this association might not apply to the patients with the thrombolysis treatment. The interpretation of HVS distribution score with acute ischemic stroke patients should be discussed dependent on thrombolysis.

Blood pressure variability and prognosis in acute ischemic stroke with vascular compression on the rostral ventrolateral medulla (RVLM)

One of the known causes of hypertension is vascular compression on the rostral ventrolateral medulla (RVLM). However, it remains unknown whether RVLM vascular compression causes the significant variability in blood pressure observed during acute ischemic stroke. The purpose of this study was to evaluate differences in blood pressure variability and prognosis in acute ischemic stroke patients based on the presence or absence of RVLM vascular compression. We evaluated 56 patients with acute ischemic stroke. Blood pressure was measured every 6 h for 72 h after admission and evaluated with successive variation (SV). The presence of RVLM vascular compression was evaluated using time-of-flight 3D magnetic resonance imaging. Neurological severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS) at admission and 14 days after admission, and clinical improvement was determined by taking the difference in the NIHSS scores between admission and at 14 days. Patient clinical outcome was evaluated with the modified Rankin scale on discharge. Vascular compression of the RVLM was identified in 15 patients (26.8%). The proportion of patients showing clinical improvement was significantly higher in the non-compression group (odds ratio, 0.21 (95% CI=0.06–0.78); P=0.01). The SV value for systolic blood pressure was significantly higher in the compression group (P<0.0001). We found that patients with RVLM vascular compression had a greater variability in blood pressure during the acute ischemic stroke phase, which may be related to poorer prognosis.

Various meteorological conditions exhibit both immediate and delayed influences on the risk of stroke events: The HEWS–stroke study

We hypothesized that meteorological conditions on the onset day and conditions on the former days may play important roles in the modulation of physical conditions. Associations of meteorological factors and their changes in former days with stroke onset are of interest. We conducted a multicenter retrospective study to evaluate the frequency of stroke events and their interaction with meteorological conditions and their daily changes. Acute stroke patients (n = 3935, 73.5±12.4 years, 1610 females) who were admitted to 7 stroke hospitals in three restricted areas were enrolled in this study. Poisson regression models involving time-lag variables was used to compare daily rates of stroke events with mean thermo-hydrological index (THI), atmospheric pressure, and their daily changes. We divided onset days into quintiles based on the THI, atmospheric pressure, and their daily changes for the last 7 days. The frequencies of ischemic stroke significantly increased when THI varied either cooler or warmer from a previous day (extremely cooler, risk ratio (RR) 1.19, 95% confidence interval (CI) 1.05 to 1.34; extremely warmer, RR 1.16, 95% CI 1.03 to 1.31; r2 = 0.001 for the best regression, p = 0.001). Intracerebral hemorrhage frequencies significantly decreased on high-THI days (extremely high, RR 0.72, 95% CI 0.54 to 0.95; r2 = 0.013 for the best regression, p<0.001) and increased in high atmospheric pressure days (high, RR 1.31, 95% CI 1.04 to 1.65; r2 = 0.009 for the best regression, p<0.001). Additionally, even after adjusting for the THI on the onset day and its changes for the other days, intracerebral hemorrhage increased when THI got extremely cooler in 4 days prior (RR 1.33, 95% CI 1.03 to 1.71, r2 = 0.006 for the best regression, p<0.001). Various meteorological conditions may exhibit influences on stroke onset. And, when temperature cooled, there may be a possibility to show delayed influence on the frequency of intracerebral hemorrhage 4 days later.

Screening for Fabry Disease in Japanese Patients with Young-Onset Stroke by Measuring α-Galactosidase A and Globotriaosylsphingosine

BACKGROUND Fabry disease is an X-linked lysosomal storage disorder caused by mutations in GLA, which encodes the enzyme α-galactosidase A (α-Gal A). Although the prevalence of Fabry disease in patients with stroke has been reported to range from 0% to 4%, few cohort studies have examined Japanese stroke patients. We aimed to clarify the prevalence of Fabry disease and the frequency of GLA mutations among patients with young-onset stroke in Japan. METHODS From April 2015 to December 2016, we enrolled patients with young-onset (≤60 years old) ischemic stroke or intracerebral hemorrhage. We measured α-Gal A activity and the concentration of globotriaosylsphingosine in plasma. Genetic evaluations were performed in patients with low α-Gal A activity or high concentrations of globotriaosylsphingosine. RESULTS Overall, 516 patients (median age of onset, 52 years old; 120 women) were consecutively enrolled in this study. Five patients (4 men and 1 woman) had low α-Gal A activity, and no patients were detected with the screen for plasma globotriaosylsphingosine levels. The genetic analysis did not identify a causative mutation responsible for classic Fabry disease in any of the patients, but 2 patients (.4%) carried the p.E66Q in GLA. CONCLUSIONS No patient with Fabry disease was detected in our young-onset stroke cohort.

A Case Report of Visual Disturbance Caused by Thrombosis of the Superior Sagittal Sinus

Superior sagittal sinus thrombosis is a rare condition caused by several diseases including malignancy. Major symptoms include headache, seizure, and motor weakness. Ocular sign is a minor symptom. The present case had visual disturbance caused by thrombosis of the superior sagittal sinus, which is an extremely rare case that was treated successfully by our team