The relationship between blood pressure (BP) and cognitive impairment (CI) and/or dementia (Dm) is more complicated than previously appreciated. In cross-sectional studies, some studies have shown positive relationship between higher BP levels and CI/Dm, while others have shown an inverse association. A U-shaped association was also reported.It is consistently reported that midlife hypertension can increase the risk for late age CI/Dm especially in those never treated with anti-hypertensive medication. Longitudinal studies on late life BP and subsequent CI/Dm have yielded mixed results. Reports that both low diastolic pressure and high systolic pressure in elderly persons were associated with subsequent development of CI/Dm might arbitrate such opposed views.High BP is positively associated with vascular CI/Dm, while it is inconsistently associated with Alzheimer disease. Several studies have shown that BP tended to decrease over the course of developing dementia. BP starts to decrease before dementia diagnosis and continues to decline afterward. Declining BP may be a consequence of the dementia process, while it is possible that low BP may predispose a subsequent development of dementia.Studies applying 24-hour BP monitoring showed increased nighttime BP patterns, non-dipper or riser, are strongly associated with CI/Dm. Non-dipper is considered to be associated with salt sensitive hypertension that is prevalent in Japan and reported to be ameliorated by the use of diuretics. Actually some reports suggested diuretic use was associated with reduced risk of CI/Dm. Especially for vascular dementia or Alzheimer disease with cerebrovascular disease, relevant use of diuretics may help preventing CI/Dm.

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Establishment of telestroke networks has been proposed to overcome regional disparities in stroke treatment in Japan. To identify potential demand for telestroke network and a prerequisite step for introduction, we performed geographic information system (GIS) analysis with questionnaire survey for hospitals in Shizuoka prefecture. The GIS analysis showed that 4.3% of the population lived in areas where they could not reach hospitals that are authorized to admit patients with acute stroke within 60 minutes. If 24/7 full telestroke support was introduced to the hospitals, 50–70 more patients could be treated by intravenous tissue plasminogen activator (tPA) annually. As a prerequisite step before introduction of telestroke network, 24% hospitals chose “an establishment of local transfer protocol for acute stroke patients with surgical indication” and 15% of hospitals chose “medical malpractice and liability”. This study revealed a potential demand for the telestroke network even in hospitals specialized for stroke treatment and that GIS analysis is useful for estimating the effects of introducing telestroke networks in a community.

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As there are no stroke specialists in medically under-served areas, the delivery of thrombolysis therapy using alteplase, the standard treatment for patients with acute ischemic stroke, is difficult. In February 2013, in Tokushima Prefectural Kaifu Hospital, we introduced a telemedicine system that uses a smartphone and the internet to treat patients with acute stroke. Using this system, physicians in this medically under-served area can relay neuro-radiological images such as CT or MRI scans and patient data any time via their smartphone to specialists such as neurosurgeons and cardiovascular surgeons at other sites. In the course of 11 months we used this system to treat 126 patients seen in the emergency room. This system facilitated the delivery of thrombolysis therapy using alteplase to four patients with acute ischemic stroke and we found telemedicine highly effective for the treatment of patients with acute stroke in medically under-served areas.

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Purpose: The purpose of this study is to analyze the diagnostic utility of 320-row detector computed tomography in dural arteriovenous fistulas (AVFs).Method: Thirty-five dural AVFs of 30 cases from 2009 to 2013 in Keio University Hospital were evaluated using 320-row detector computed tomography and catheter angiography by two physicians. The Cohen kappa statistic was used to assess interobserver and intermodality agreement. Also we investigated all cases after treatments using 320-row detector computed tomography.Results: 320-row detector computed tomography revealed fistula sites (94.3%), feeders (55.1%), venous drainage, extracranial vein and sinus occlusion (100%), and disturbance of cerebral perfusion (88%). The kappa test analysis revealed a high level of interobserver and intermodality agreement in reading fistula sites, venous drainage, disturbance of cerebral perfusion, extracranial vein, and sinus occlusion (κ, 0.86–1.00). In terms of reading venous drainage, 320-row detector computed tomography had the advantage, in some cases, of detecting the transformation of Cognard's type in two cases during follow-up period.Conclusions: 320-row detector computed tomography is a useful tool for making the initial definitive diagnosis and checkup during follow-up period of dural AVFs.

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A 49-year-old male was admitted to our hospital with subarachnoid hemorrhage. After clipping of right middle cerebral artery aneurysm, external and internal decompression were done for extensive brain edema. During subacute period, the bilateral parieto-temporo-occipital subcortical region showed aggravated brain edema. MR venogram revealed a left transverse and sigmoid sinus thrombosis. Systemic heparinization was started but brain edema worsened. Emergency thrombectomy was performed using balloon angioplasty and the thrombus in the sinus was completely removed. However, left internal jugular vein stenosis remained despite successive balloon dilation. Carotid Wallstent^® was placed and the patient improved dramatically. MR venogram of 28 months later showed patent stent. This is assumed to be the first case in Japan treated with stent placement for the jugular vein stenosis accompanied by cerebral venous sinus thrombosis in the literature. However, evidence of the endovascular therapeutic procedure for cerebral venous sinus thrombosis has not been established yet. We expect further studies of this treatment in this endovascular era.

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An 83-year-old male exhibited cognitive impairment and deteriorated in few days. MRI T2WI and FLAIR image showed high signal intensity and low signal intensity on T2^*WI in the thalami. Angiographical images showed small dural arteriovenous fistula at the falco-tentorial junction with straight sinus thrombosis. A part of the venous drainage refluxed and congested to the area of bilateral internal cerebral vein. Based on these findings, the venous congestion of thalami caused the patient to cognitive decline. The dural arteriovenous fistula was treated by transvenous embolization with coil via occluded straight sinus. The cognitive function of the patient made a remarkable recovery about 1 month after the embolization. We report a rare case of cognitive dysfunction with bithalamic lesion caused by falco-tentorial dural arteriovenous fistula with thrombosed straight sinus.

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We present five patients with non-valvular atrial fibrillation (NVAF) with left atrial thrombus, which was detected by transesophageal echocardiography for acute-phase cardioembolic stroke and disappeared after dabigatran etexilate (DE) administration. The mean age at onset was 83 years, and three of the five patients were women. The mean maximum diameter of the left atrial thrombi was 13 mm. Unfractionated heparin was administered and then switched to DE in three patients, and warfarin started before the stroke onset was switched to DE in one patient. In one patient, warfarin started before the onset was switched to unfractionated heparin after the onset and then switched to DE (110 mg b.i.d. for 4 patients, 150 mg b.i.d. for 1 patient). With DE administration for a mean of 18 days (range, 6–39 days) starting 3, 5, 5, 7, and 18 days after the onset, the left atrial thrombus resolved completely without recurrent ischemic events in all patients. The results of this study suggest the efficacy of early administration of DE for the prevention of recurrent thromboembolism in NVAF patients with acute-phase cardioembolic stroke and positive left atrial thrombus.

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We report a case of multiple vascular pathologies including a fenestration of the middle cerebral artery, aneurysms of the anterior communicating artery, and an arteriovenous malformation.A 52-year-old female presented with disturbance of consciousness. Head computed tomography showed a subarachnoid hemorrhage and an intracerebral hemorrhage, and cerebral angiography showed a fenestration of the right middle cerebral artery, aneurysms of the anterior communicating artery, and an arteriovenous malformation in left frontal operculum. We performed endovascular embolization for Acom aneurysms. Postoperative course was uneventful.This combination of vascular pathology was rare.

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A 43-year-old man with a partially thrombosed vertebral artery aneurysm was incidentally diagnosed by chance in the examination of chronic headache. Magnetic resonance imaging (MRI) showed enhancement of the thickened wall and angiography detected staining. This case was successfully treated by internal trapping. His clinical symptoms gradually improved and he fully recovered. Follow-up MRI at 2 years after embolization showed decreased size of the aneurysm.

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A 58-year-old man suddenly developed difficulty in conversation and in using the wireless remote controller, in June 2012. He was referred to us because a brain MRI showed bilateral thalamic signal abnormality in another clinic.Neurological examination revealed disorientation and anisocoria. MRI confirmed brain infarction in the bilateral paramedian thalamus and left hypothalamus. One month later, CT angiography demonstrated that a thalamo-perforating artery branched off from right posterior cerebral artery (P1) with a common trunk and periphery bifurcated. This is a rare case a Percheron artery was identified by CT angiography.

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