Purpose: To elucidate the characteristics of stroke related to infective endocarditis (IE), we retrospectively reviewed the records of patients with IE at our hospital. Methods: Ninety patients with IE (mean age 63.8 ± 17.4 years) were selected in this study, and neuroradiological findings and background factors related to stroke were evaluated in all subjects with stroke. Results: Of the 90 subjects with IE, 25 (28%) had stroke (18 cerebral infarctions, 5 intracerebral hemorrhages, and 2 subarachnoid hemorrhages). Subjects with a modified Rankin scale ≥3 at discharge were significantly more prevalent in the stroke group than in the non-stroke group (52% vs. 28%, P = 0.046). The majority of cerebral infarctions were detected in the territory supplied by the cerebral cortical branches. Intracerebral hemorrhages were found with multiple hematomas in the subcortical or cerebellar regions. Cerebral infarctions mainly occurred in the initial stage of IE, and intracerebral hemorrhage or subarachnoid hemorrhage developed after the appearance of several physical symptoms of IE. Conclusion: Stroke occurred in almost one-third of IE patients. In particular, ischemic stroke occurred in the initial stage of IE.

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Background and Purpose: Transient ischemic attack (TIA) is a high risk of subsequent ischemic stroke. We have reported one case receiving intravenous recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke occurring during hospitalization for TIA. We analyzed other consecutive patients receiving rt-PA for acute ischemic stroke occurring during hospitalization for TIA. Methods: We reviewed four cases (2 males and 2 females, aged from 74 to 89 years) from our facility’s rt-PA database between October 2005 and December 2013. Results: The ABCD² score of preceding TIA ranged from 4 to 6. Three of the four patients had atrial fibrillation and major artery occlusion on admission and/or time of the occurrence of subsequent ischemic stroke. Diffusion weighted imaging (DWI) on admission revealed a hyperintense lesion in the left medial thalamus in one patient. Elapsed time from the index TIA to the time of occurrence of ischemic stroke ranged from 2 hours to 3 days. The National Institutes of Health Stroke Scale score at the onset of ischemic stroke ranged from 7 to 30. The onset-to-treatment time of rt-PA was 33, 33, 160, and 170 minutes, respectively. Modified Rankin Scale score at 90 days was 0 in 2 patients and 5 in one patient. The other one patient could not be followed up. Conclusions: Patients with TIA being at high risk for subsequent ischemic stroke should be immediately hospitalized. To avoid delay in timely treatment including acute revascularization therapy, occurrence of subsequent ischemic stroke should be always kept in mind.

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Background and Purpose: We investigated the clinical usefulness of thin section diffusion weighted images (DWIs) in patients with acute cerebral infarction. Methods: Thin section DWI was examined in addition to conventional DWI in 258 patients with suspected acute cerebral infarction. Results: 1) Of these patients, 124 patients were diagnosed with cerebral infarction. 2) Of 124 patients, 112 patients (90.3%) were conventional DWI positive. 3) One hundred and twenty patients (96.7%) were thin section DWI positive, and detection rate was significantly higher than conventional DWI (p=0.0078). 4) The frequency of lacunar infarction revealed thin section DWI that was significantly higher than the frequency with conventional DWI (p=0.0067). 5) The comparison of interval times from onset to evaluation and distribution patterns of cerebral infarction showed no significant difference. Conclusion: The detection rate of cerebral infarction with thin section DWI was significantly higher than with conventional DWI. We recommend thin section DWI for patients with suspected acute cerebral infarction especially when conventional DWI is negative.

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Background and purpose: For secondary prevention of cardiogenic cerebral embolism with nonvalvular atrial fibrillation (CE-NVAF), non-vitamin K antagonist oral anticoagulants (NOACs) have become popular. This study sought to evaluate the current status of choice of oral anticoagulants (OACs), including warfarin, dabigatran, rivaroxaban, and apixaban. Methods: We studied a total of 197 patients with CE-NVAF who had been treated in our institute between June 2012 and February 2015. Among these, 80 patients were also examined who were treated between March 2014 and February 2015, when three NOACs had been available equally. Results: In the 197 patients, warfarin was chosen for 69 patients (35.0%) and NOACs for 100 (50.8%). Switching from NOACs to warfarin during followup was made in nine patients (9%) with severe disability. Compared to warfarin, NOACs were preferentially chosen for the patients with lower severity, better renal function, and better prognosis. In the 80 patients, multiple comparison tests among three NOACs showed statistical difference on initial National Institutes of Health and Stroke Scale score between rivaroxaban and apixaban groups. Conclusion: The present study revealed that the NOACs were chosen not only medically but also socioeconomically by attending physicians, which may suggest that public education of anticoagulation therapy is important for primary care doctors, pharmacists, and caregivers including patients’ family.

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A 67-year-old man was admitted to our hospital with a sudden onset of left dominant quadriparesis and left sensory impairment. The patient had diagnosed with Stanford type B aortic dissection (AD) and ischemic stroke in the left posterior inferior cerebellar artery (PICA) territory 1 year before his admission. Magnetic resonance imaging revealed acute ischemic stroke in the left PICA and anterior spinal artery territory. Transesophageal echography (TEE) was performed to identify the etiology. The false lumen of the type B AD was partially thrombosed, and the primary intimal tear was found to be close to the origin of the left vertebral artery (VA), which arose from proximal portion of left subclavian artery. Moreover, color Doppler TEE revealed a retrograde flow from the false lumen to the left VA. We considered that the thrombus in the false lumen of the type B AD could be an embolic source of repetitive strokes of the left VA territory. The patient was treated with anticoagulant therapy to prevent the formation of thrombus in the false lumen. No recurrence was observed until 1 year of follow-up.

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Case: A 73-year-old male who had atrial fibrillation, hypertension, and type 2 diabetes suffered from cerebral infarction and was transferred to our hospital for the treatment of left internal carotid artery (ICA) stenosis. Carotid ultrasonography (CUS) disclosed the existence of hypo-echoic plaque with ulcer which indicated vulnerable lesion. High signal plaque on T1 weighted MRI corresponded with CUS findings. Because the degree of stenosis was 76.8% on digital subtraction angiography, carotid artery stenting (CAS) was performed. In-stent plaque protrusion (ISPP) occurred after placement of self-expanding stent, and therefore ultrasound examination was conducted several times for the follow-up of ISPP. Although CUS was difficult to determine the ISPP, it was well visualized by using contrast enhanced CUS (CEUS). The places and shapes of ISPP were evaluated on CEUS, which corresponded with those on computed tomography angiography. Conclusion: CEUS was useful for the evaluation of ISPP after CAS.

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A 61-year-old woman who presented with sudden dysarthria and left hemiplegia was admitted to our hospital. Brain MRI (diffusion-weighted image; DWI) showed high-intensity lesions from the right putamen to the corona radiata. Her symptoms improved within 2 hours, and the high-intensity lesions were not apparent on the brain MRI obtained 6 days after admission. Although warfarin therapy was started, she experienced a transient ischemic attack (TIA) again at 30 and 38 days after the first attack. Cilostazol was administered in addition to warfarin, but she experienced TIAs 22 and 26 days thereafter. Her therapy was changed from warfarin to cilostazol plus clopidogrel therapy, but she experienced a 6th episode of transient dysarthria and left hemiparesis 20 days later. Despite the addition of aspirin to cilostazol and clopidogrel, she experienced a last ischemic attack. The dysarthria and left hemiparesis (NIHSS 9) lasted for 72 hours, and slight left hemiparesis remained thereafter. MRI fluid-attenuated inversion recovery (FLAIR) image of the head revealed high-intensity lesions from the putamen to the corona radiata (3 slices). Blood examination, cerebrospinal fluid analysis, and gadolinium-enhanced brain MRI showed no evidence of demyelinating disease, cerebral vasculitis, or malignant brain tumor. She was diagnosed with branch atheromatous disease. This case had a characteristic course of repeated TIAs with reversible brain MRI lesions over a 3-month period.

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A 34-year-old primigravida at 9 weeks of gestation presented with sudden headache and consciousness disturbance. Computed tomography (CT), CT angiography (CTA), and angiography showed subarachnoid hemorrhage and a large ruptured aneurysm of the left internal carotid artery. She was immediately admitted and underwent bilateral ventricular drainage, and her consciousness improved slightly. Endovascular embolization of the aneurysm was then performed, resulting in almost complete occlusion of the aneurysmal sac. The patient recovered fully, and a healthy baby was delivered at the 38th week of gestation via cesarean section. Though this case had a good outcome, management of ruptured cerebral aneurysms during early pregnancy requires more discussion.

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We describe a case of arteriovenous malformation (AVM) presenting with spontaneous alteration of perinidal edema. A 62-year-old man with a history of subcortical hemorrhage was admitted to our hospital because of paresis and numbness of the left lower extremity. Computed tomography (CT) demonstrated a low density area in the right parietal lobe. T₂^* magnetic resonance imaging (MRI) images revealed a hypo-intense lesion surrounded by edema that was hyper-intense on T₂-weighted images and iso-intense on diffusion-weighted images. A cerebral angiogram demonstrated a small AVM with a draining cortical vein emptying into the superior sagittal sinus. A follow-up CT scan demonstrated worsening of the edema around the AVM, accompanied by transient worsening of symptoms. One month later, we performed surgical resection of the AVM. Before the operation, his symptoms had improved. CT scan confirmed regression of the brain edema. MRI demonstrated the alteration of description of cortical vein connected with the drainer. Our case suggests that the perinidal edema was induced by obstructed venous drainage due to stenosis of the draining cortical vein, and improved by restored venous drainage.

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A 41-year-old man presented with progressively deteriorating headache and behavioral disorder. Neurological examination showed slight cognitive decline and neck stiffness. Brain MRI demonstrated diffuse thickening of the dura mater. The etiology of the dural thickening was considered to be idiopathic because no infectious, autoimmune, or neoplastic disorders could be found. MR venography revealed occlusion of the superior sagittal and transverse sinuses. The diagnosis was cerebral venous sinus thrombosis due to idiopathic hypertrophic cranial pachymeningitis (IHPM). Subsequent treatment with corticosteroids and an anticoagulant led to full recovery. In a case of cerebral venous thrombosis with headache, it is required to examine the dural thickening and vice versa in a case of IHPM, an association of cerebral venous thrombosis should be considered.

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