Prolonged central motor conduction time and pyramidal tract degeneration in amyotrophic lateral sclerosis.

Electrophysiological methods to detect the degeneration of the upper motor neuron system have not been fully established in patients with amyotrophic lateral sclerosis (ALS). This may be partly because the parallel demonstration of electrophysiology and a corresponding pathological abnormality is insufficient, and because a substantial number of patients with ALS do not exhibit upper motor neuron degeneration. Recently, we encountered 2 patients with ALS who had been examined for abnormal central motor conduction time (CMCT) using transcranial magnetic stimulation within a 20-day period prior to their death. Autopsy revealed that 1 patient had marked pyramidal degeneration with prolonged CMCT; in contrast, the other patient had no obvious pyramidal degeneration and showed normal CMCT. Both the patients with contrasting clinicopathological differences contributed to the identification that the prolongation of CMCT was possibly linked to the degeneration of the corticospinal tract. This report indicates that CMCT is useful for predicting the severity of upper motor neuron degeneration in patients with ALS.

Recurrent Stroke Incidence and Etiology in Patients with Embolic Stroke of Undetermined Source and Other Stroke Subtypes.

AIMS: This study aimed at clarifying the incidence of recurrent stroke and its etiology in patients with embolic stroke of undetermined source (ESUS) and other stroke subtypes in both the acute and chronic periods. METHODS: A total of 645 patients who were admitted with acute ischemic stroke (IS) between March 2015 and August 2019 were enrolled. Among them, 511 patients with ESUS, cardioembolism (CE), large artery atherosclerosis (LAA), or small vessel disease (SVD) were analyzed in this study. After discharge, 391 patients who visited the outpatient clinic were followed up until August 2020. The outcome was stroke recurrence. RESULTS: In the acute admission, recurrence rates were 7.6%, 8.1%, 18.8%, and 2.2% in patients with ESUS, CE, LAA, and SVD, respectively, and there were significant differences between the groups. The subtype of recurrence was almost identical to that of the index stroke. In the outpatient clinic, the annual recurrence rates were 4.4%, 4.3%, 6.0%, and 2.9% in ESUS, CE, LAA, and SVD, respectively, and no difference was observed. Subtypes of recurrence in outpatients with ESUS included ESUS, intracerebral hemorrhage (ICH), and SVD. Patients with ESUS and SVD had a higher risk of ICH during follow-up. CONCLUSIONS: Although the risk of recurrence was comparable between patients with ESUS and CE and intermediate between patients with LAA and SVD, in the acute admission unit, the risk in outpatients was similar among all subtypes. ESUS was the most recurrent stroke subtype in outpatients with ESUS. The risk of hemorrhagic stroke was significant in patients with SVD and ESUS.

Localization of Infratentorial Lesion could Predict Patent Foramen Ovale as an Etiology in Embolic Stroke of Undetermined Source.

AIM: Embolic stroke of undetermined source (ESUS) is a clinical construct introduced to describe cryptogenic stroke cases with ambiguous diagnoses. Cardiac causes are recognized as a major cause of ESUS, Patent foramen ovale (PFO) being among them. We aimed to investigate the relationship between infarct patterns and PFO in patients with ESUS. METHODS: We evaluated 190 consecutive patients with ESUS registered in the Tokyo Women's Medical University Stroke Registry. Among them, 94 patients who underwent magnetic resonance imaging and angiography, as well as transthoracic and transesophageal echocardiography, were included in this study. The infarct patterns were classified according to location (infratentorial or non-infratentorial lesions), size (small or large infarcts), and number (single or multiple lesions). RESULTS: Prevalence of PFO was significantly higher in patients in the infratentorial than those in the non-infratentorial lesion group (40.7% versus 14.9%, respectively; P=0.007). However, neither lesion size nor number were associated with PFO. In multivariate logistic regression analysis, the presence of infratentorial lesions was independently associated with PFO in ESUS patients (odds ratio: 2.18; 95% confidence interval: 1.24-3.95; P＜0.007). In 21 patients with PFO, large PFOs were more prevalent in the infratentorial than in the non-infratentorial lesion group. CONCLUSIONS: Infratentorial lesions may be independently associated with PFO in patients with ESUS. The presence of infratentorial lesions could predict the presence of PFO in ESUS cases.

Prevalence of Microembolic Signals in Embolic Stroke of Undetermined Source and Other Subtypes of Ischemic Stroke.

Background and Purpose- Embolic stroke of undetermined source (ESUS) has been proposed to cause thromboembolic infarction from unknown but potential embolic sources. However, an embolus remains undetected in ESUS. The goal of this study was to characterize the prevalence and risk factors of microembolic signals (MESs) in ESUS. Methods- We examined 108 patients with acute ischemic stroke in the internal carotid artery territory or transient ischemic attack within 14 days of symptom onset and who were admitted to our hospital between April 2017 and March 2019. MESs were monitored in the middle cerebral artery on transcranial Doppler for 60 minutes. We examined the prevalence and number of MES in ESUS and other stroke subtypes, such as cardioembolism, large artery atherosclerosis, cerebral small vessel disease, and transient ischemic attack. The present study was registered in University Hospital Medical Information Network Clinical Trials Registry (UMIN000031913). Results- MESs were detected in 33 (31%) of 108 patients. ESUS showed the highest proportion (12/24 [50%]), followed by large artery atherosclerosis (8/20 [40%]), cardioembolism (6/18 [33%]), transient ischemic attack (4/24 [17%]), and cerebral small vessel disease (3/21 [14%]). Univariate analysis showed that higher systolic blood pressure, body mass index, hemoglobin A1c, and ESUS were significantly associated with MES. In multiple logistic regression analysis, ESUS remained significantly associated with MES after adjustment for described covariates from univariate analysis (odds ratio, 2.86 [95% CI, 1.01-8.08]). Conclusions- This study demonstrated significant association of ESUS with MES, supporting the embolic nature of this stroke subtype. Registration- URL: https://upload.umin.ac.jp. Unique identifier: UMIN000031913.

Recurrent Cerebral Infarction Due to Benign Uterine Myoma.

The hypercoagulable state in patients with cancer has been shown to be closely associated with ischemic stroke. However, it is unlikely that benign tumors are related to stroke. The development of benign uterine tumors is common in middle-aged women. Previous studies have shown cases of ischemic stroke with benign uterine tumor, but the causal relationship between these 2 remain unknown. We report a case of recurrent ischemic stroke in a middle-aged woman who had a benign uterine tumor. After excision, there was no recurrence for 2 years. Microemboli detection, clinical course and histological findings support a relationship between uterine tumor and ischemic stroke.