Background and Purpose: Thrombolytic treatment with alteplase at 0.6 mg/kg is approved for use within 3 h of stroke onset in Japan. Thus, only a small percentage of patients can benefit. A meta-analysis and more recent studies suggest a benefit to patients beyond 3 h with alteplase at 0.9 mg/kg or desmoteplase. We assessed the efficacy and safety of intravenous alteplase at 0.6 mg/kg more than 3 h after stroke onset in patients with acute MCA occlusion who were selected using perfusion-diffusion mismatch.
Methods: Patients with MCA occlusion eligible for intravenous alteplase within 3 h were selected using MRI (DW, FLAIR, T2*, T2)/MRA and beyond 3 h using evidence of perfusion-diffusion mismatch. Recanalization was evaluated using MRA within 24 h after treatment. Baseline characteristics, recanalization rates, early and late good clinical outcomes (NIHSS scores of 0 to 1 or 8-points or greater improvement at 24 h and mRS scores of 0 or 1 on the 90th day), symptomatic intracranial hemorrhage (within 72 h) and mortality (at the 90th day) were evaluated for both groups. Also for both groups, the relationships between recanalization and early and late good clinical outcomes were evaluated.
Results: 63 patients with MCA occlusion were treated using intravenous alteplase within 3 h (n=53) and beyond 3 h (n=10). No statistically significant differences were found between the two groups for recanalization rates (52.8 vs. 70.0%), early and late good clinical outcomes (early: 41.5 vs. 60.0%, late: 37.7 vs. 50.0%), symptomatic intracranial hemorrhage (0 vs. 0%), or mortality (1.9 vs. 0%).
Conclusion: Our data suggest that intravenous alteplase at 0.6 mg/kg beyond 3 h after MCA occlusion for patients selected using perfusion-diffusion mismatch has the same efficacy and safety as treatment within 3 h. However, a larger sample size is needed to evaluate the relationship between recanalization and clinical outcomes of the treatment beyond 3 h.

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Background: The factor most greatly affecting the incidence of stroke is atmospheric temperature. Incidences have been reported to be the highest in winter and the lowest in summer, but this is not necessarily consistent. This is because meteorological effects are complex, and furthermore, problems have been pointed out in the research methodology, such as limited periods of observation and limited study population sizes.
Method: The subjects of the present study were 46,031 stroke patients who were admitted to the Rosai General Hospitals located in various cities in Japan for medical treatment from the 2002 fiscal year to the 2008 fiscal year. The number of incidences were compared by month and by type of stroke. For meteorological classification, four regional groups were studied.
Results: The incidence of cerebral hemorrhage was low in summer and high in winter for both males and females, with the lowest month differing by one month between Northern and Western Japan. The incidence of subarachnoid hemorrhage was high in females and was low in summer and higher from autumn to winter. The incidence of cerebral hemorrhage did not show an evident seasonal difference. The incidence of both lacunar infarction and atherothrombotic infarction showed a bimodal distribution with a rapid increase in summer and a repeat increase in January. Cardioembolic infarction showed a high incidence only in winter.
Conclusion: Measures should be taken to prevent stroke, taking into consideration not only the living environment but also the occupational environment that accompanies changes in the global environment.

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A 33-year-old man had episodic symptoms of motor aphasia and sensory disturbance of the right side of the face that lasted about one minute while running. He had a second attack two days after the first attack. A brain MRI revealed a cortical infarct in the left middle cerebral artery territory. Difficulty was encountered in using duplex carotid ultrasonography with a linear probe to evaluate the left extracranial cervical internal carotid artery (LECICA) with a high bifurcation. As an alternative evaluation, a microconvex probe (MCP) showed the LECICA lesion with a narrow lumen surrounded by a hypoechoic lesion and with an increased vascular diameter for a length of 2 cm, starting from 2 cm distal to the carotid bulb. In addition, B-flow imaging (BFI) clearly showed echogenic structures of a hyperechoic intravascular lumen; a hypoechoic lesion with a subtle flow signal, which indicated a false lumen; and a mobile membranous septal structure between them. The findings of contrast-enhanced CT angiography were consistent with those of the B-flow imaging. The LECICA lesion was diagnosed as a spontaneous dissection. Carotid ultrasonography using MCP with BFI can improve the diagnosis of extracranial carotid artery dissection, which has been difficult for patients with high bifurcation of the carotid artery.

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This is a case of a 90-year-old-female with diagnosed atrial fibrillation who was admitted to our hospital suffering from right hemiparalysis and aphasia. The initial NIH Stroke Scale (NIHSS) score was 25 points. On diffusion-weighted imaging (DWI), a diffuse high intensity area was detected in the left insular cortex. Intravenous thrombolysis using tissue plasminogen activator (rt-PA, 40 kg, 24 mg) was administered within 3 hours (1 hour and 45 minutes) of symptom onset, which was caused by acute embolic cerebral infarction. After this treatment, her motor weakness and NIHSS score were improved by 17 points within 1 hour and 30 minutes. However, just after, she suddenly went into shock (maximal blood pressure was 60 mmHg) and into a coma. On head and whole-body CT scans, no intracranial hemorrhage was detected, but a large volume of pericardial effusion resulting in cardiac tamponade was detected. She died 3 hours and 35 minutes after treatment, and a pathological autopsy was performed. The autopsy showed a recent myocardial infarction and a blow-out-type of cardiac rupture of the posterior wall of the left ventricular. We should be alert to fatal cardiac complications of rt-PA treatment for patients with concomitant stroke and myocardial infarction.

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A 72-year-old man was admitted with a chief complaint of involuntary movement of the right arm and leg that had persisted for three weeks. Although chorea of the right arm and leg was observed, the patient had no other neurological abnormalities. SPECT revealed reduced blood flow from the left frontal lobe to the parietal lobe, but no abnormal findings were observed on brain images (brain CT, MRI) or electroencephalogram. Following admission, the involuntary movement spontaneously resolved and disappeared, and the patient was subsequently discharged. However, two days later, he was readmitted due to the onset of aphasia and paralysis of the right arm and leg. Brain MRI showed acute cerebral infarcts dispersed in the left basal ganglia, frontal lobe, and temporal lobe, while MRA revealed occlusion of the left internal carotid artery. Although no clear abnormalities had been detected on imaging tests and electroencephalogram at the initial admission, based on the patient’s course, the involuntary movement of the right arm and leg that had been initially observed was thought to have been limb shaking (LS) associated with hemodynamic factors resulting from the lesion in the left internal carotid artery. As LS generally has a hemodynamic mechanism, symptoms often manifest transiently and rarely persist for a few weeks, as in the present case. If we had initially suspected a cerebrovascular disorder at the first medical examination, we might have prevented cerebral infarction. Therefore, we consider this to be an important instructive case.

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A 47-year-old woman was referred to the emergency room of our hospital because of left hemiparesis and speech disturbance that she had first noticed when she woke up at 2:30 that morning. She gave a history of suffering from severe anorexia over the previous 10 days, during which she had not consumed much other than liquids. On arrival at 4:30 AM, the patient was found to be fully conscious and oriented, and a neurological examination revealed left hemiparesis involving the face. Head CT and head MRA did not reveal any abnormal findings, while diffusion-weighted MRI of the head revealed high-intensity areas in the posterior limb of the internal capsule and splenium of the corpus callosum bilaterally. The blood glucose concentration was 35 mg/dl. The symptoms and signs resolved promptly following intravenous administration of glucose. A laboratory examination revealed evidence of severe hyperthyroidism, and a test for TRAb was positive; the patient was diagnosed as having Basedow’s disease. The plasma levels of IRI and other glucose-regulating hormones were within the normal range, except for an elevated cortisol level, and a test for anti-insulin antibodies was negative. Based on these results, we concluded that the patient presented with hypoglycemia as a result of severe starvation in the presence of hyperthyroidism. To the best of our knowledge, this is the first report of Basedow’s disease manifesting as hypoglycemic hemiparesis. This case suggests the importance of ruling out hypoglycemic hemiparesis before considering rt-PA therapy in patients with Basedow’s disease.

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A 72-year-old male was admitted with right neck pain and hemiplegia. Mild right facial palsy and Horner’s syndrome were noted. Pain and heat sensation were disturbed in the face and the left hemibody. Touch and deep sensation were diminished on the right side. The right soft palate, sternocleidomastoid muscle, and trapezius muscle exhibited paresis. Bilateral Babinski reflexes were positive. MR images revealed a dorsolateral infarction of the right medulla and a lateral infarction of the upper spinal cord. A small cerebellar infarction was noted. Cerebral angiography showed occlusion of the proximal portion of the bilateral vertebral arteries, and the branches of the thyrocervical trunks worked as collateral circulation. The mechanism of this infarction was suspected to be artery-to-artery embolism. Three months later, the patient was able to walk using a cane. After four years, the patient was admitted with severe paraplegia. Cerebral MRI revealed a brain infarction in the medial right precentral gyrus. No other new lesions were observed. The patient again recovered and was able to walk using a cane, but not as well as before. One possible mechanism for this pattern of recovery is reorganization of the right motor cortex such that the non-affected medial part of the right precentral gyrus acquired the ability to control both legs. When the area was damaged by the second attack, paraplegia resulted. This is the first report of tandem infarctions of unilateral spinal cord and cerebellum resulting in paraplegia.

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A 16-year-old male was admitted to our hospital with fever, headache, recurrent general convulsion, and consciousness disturbance. A cerebrospinal fluid (CSF) examination revealed increased CSF pressure but no other abnormal findings. Diffusion-weighted MRI revealed a blurred high intensity area without a reduction in the apparent diffusion coefficient in both parietal lobes. The anterior half of the superior sagittal sinus was not shown by angiography and MR venography, and coagulation studies revealed a considerably decreased antithrombin (AT) III value. He was diagnosed with cerebral venous thrombosis (CVT) derived from an ATIII deficiency. Because systemic anticoagulation and anticonvulsant therapy were ineffective, intraarterial thrombolytic therapy using urokinase was administered, but no dissolution of the clot was achieved. Mechanical clot disruption was performed as a secondary treatment using a percutaneous transluminal angioplasty (PTA) balloon catheter, and recanalization was achieved. Anticoagulation therapy with heparin and an AT agent was performed subsequently, and the patient recovered without sequelae. After 2 months, MRI revealed nothing abnormal except a microbleed in the right parietal lobe. Systemic anticoagulation with heparin is thought to be a standard therapy in CVT, but managing patients with ATIII deficiency is difficult because heparin is not effective in a low ATIII environment. Our experience suggests that PTA is an effective treatment for CVT, especially in patients with hemostatic abnormalities. Early diagnosis and appropriate intervention prevent a poor prognosis for CVT.

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We report on a patient who presented with acute internal carotid artery (ICA) occlusion and was recanalized completely using a novel embolectomy device (Merci Retriever) after failed intravenous tPA therapy.
A 58-year-old man who suffered left paralysis and dysarthria was transported to our institution 40 minutes after onset, and his NIHSS was 10 on admission. Diffusion MR imaging showed a small high-intensity lesion in the right middle cerebral artery territory, and MRA showed total occlusion of the right ICA. His neurological symptoms did not improve after intravenous tPA. Emergency angiography showed a severe stenosis of the right ICA bifurcation and an occlusion of the tip of the right ICA, and it was diagnosed as an artery-to-artery embolism.
A thrombectomy using a Merci Retriever was then attempted after successful carotid stenting. After the first procedure, the occluded ICA was opened to the distal M1 portion of middle cerebral artery. The complete recanalization of the ICA was obtained after the second procedure. His neurological symptoms improved markedly, and his modified Rankin Scale score was 1 on discharge. An endovascular embolectomy using a Merci Retriever can significantly restore the blood flow of an occluded ICA during acute ischemic stroke, which is otherwise expected to have a poor outcome.

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A 65-year-old woman who had undergone a clipping surgery for a ruptured left middle cerebral artery aneurysm about 2 years prior showed right hemiparesis and aphasia and was diagnosed with a severe stenosis of her left middle cerebral artery caused by a cerebral artery dissection. She received conservative therapy and recovered from the symptoms. We simultaneously performed computed tomographic angiography (CTA) and CT perfusion (multimodal CT imaging) at the onset of the disease, 1 month later, and 3 months later and were able to clearly evaluate her angiographic findings and cerebral perfusion at each phase. Through this case of cerebral artery dissection, we report the usefulness of the multimodal CT imaging method.

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We report the case of a patient with an anterior cerebral artery dissecting aneurysm associated with fibromuscular dysplasia (FMD). A 50-year-old woman was admitted to our hospital because she complained of sudden pain in the occipital region with muscle weakness on the left side while driving a car. Brain computed tomography and magnetic resonance imaging showed a fresh cerebral infarction and subarachnoid hemorrhage in the right frontal lobe. Cerebral angiography revealed string of beads lesions in both of the internal carotid arteries as well as an accumulation of contrast media in the right anterior cerebral artery. These data suggested that the patient developed the cerebral infarction and subarachnoid hemorrhage due to dissection of the right anterior cerebral artery associated with FMD. Her symptoms gradually disappeared after bed rest and antihypertensive drugs, with no remaining neurological symptoms. FMD should be considered in the differential diagnosis of patients with cerebral artery dissection, especially those with anterior cerebral artery dissection.

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Brain CT and MRI are essential inspections in neurology, but they are difficult for patients to understand. I have drawn simple topographies of neurological brain mappings on CT axial diagrams for co-medical staff in the past. This time, I modified the drawing based on evidence from recent reports.

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