Purpose: The characteristics of carotid artery plaques were evaluated by both MRI and enhanced CT and the results were compared between the two modalities.
Methods: Between October 2007 and September 2009, 35 vessels in 35 patients with carotid artery stenosis of more than 70% were treated by carotid artery stenting and included in the analysis. Nineteen vessels demonstrating high signal intensity on BB-MRI were categorized as an unstable plaque group (U group), and 16 demonstrating iso-low signal intensity on BB-MRI were categorized as a stable plaque group (S group). CE-CT evaluation of the carotid plaques was conducted by obtaining average CT numbers in Hounsfield units (HU) of three random regions-of-interest (ROI) in each plaque. In addition, plaque/muscle ratios (P/M) were measured by BB-MRI T1W. The CT numbers of the U and S groups and the correlation between HU and P/M ratios were evaluated.
Results: The average CT number of the U group was 35.4 HU and that of the S group was 80.2 HU, with a significant difference between the two groups by the Mann-Whitney test (p < 0.01). Furthermore, there was a significant correlation between the HU and P/M ratios in the plaques (r = -5.89, p < .0001).
Conclusion: In assessing carotid plaques, a good correlation between MRI and CT findings was obtained in this study. Since diagnosis by CT is more speedy and simpler than with MRI, this diagnostic modality may thus be preferable for evaluation of carotid lesions.

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Background and Purpose: Predicting neurological deterioration in ischemic stroke patients with initially mild symptoms at onset is difficult in the very early phase of treatment. Prevention is often difficult after neurological deterioration. We analyzed the clinical characteristics of progressed cases.
Methods: We retrospectively reviewed 451 consecutive patients with acute ischemic stroke who were admitted to our institute within 48 h of their symptom onset. Their National Institutes of Health Stroke Scale (NIHSS) scores on admission were equal to or less than five points. Progressing ischemic stroke is defined as neurological deterioration when a two-point or more increase is observed in NIHSS scores within one week of onset. We statistically investigated the correlation between progressing ischemic stroke and patient characteristics, stroke mechanisms, lesion location, and medication taken.
Results: One hundred and twenty four patients (27.5%) were defined as having progressing ischemic stroke. Based on logistic regression analysis, older age, non-lacunar infarction, and corona radiata or pontine lesion were defined as independent risk factors for progressing ischemic stroke.
Conclusions: Corona radiata or pontine lesion was an independent risk factor for progressing ischemic stroke. Aggressive intervention at the very early stage of treatment should be considered in such cases to improve the prognosis.

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Background and Purpose: Reports vary on the effect of hyperlipidemia on the clinical indexes of stroke. Methods: We extracted 16,850 stroke cases with non-medicated hyperlipidemia, diabetes or hypertension from the Japanese Stroke Databank, which contains 47,782 cases. The mean age was 67.4±14.3 years and 61% were male. Results: We analyzed the effects of hyperlipidemia on the clinical indexes of stroke. We used modified Rankin Scale, Japan Stroke Scale, National Institute of Health Stroke Scale and mortality on discharge as clinical indexes. All clinical indexes were significantly lower in patients with hyperlipidemia than in those without hyperlipidemia, after adjusting for sex and age. Conclusions: Japanese criteria of hyperlipidemia are very low: 140 mg/dl for LDL-C and 150 mg/dl for triglycerides. Therefore, many false positives may be included as having hyperlipidemia. Japan has the slimmest people in the OECD. However, mortality is greater in lean people than in obese people in Japan. Poor nutrition in the elderly may be the cause of increased risk of stroke.

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Aspiration pneumonia is a common complication among acute stroke patients and is an important factor affecting their mortality and morbidity. Thus, it is imperative to evaluate their swallowing as early as possible to prevent aspiration pneumonia. In this study, we performed both a simple swallowing provocation test (SSPT) and a water swallowing test (WST) for patients with acute ischemic stroke, and evaluated whether these tests and the combined screening method using both tests were useful. For this purpose, we performed both tests continuously on the first or second hospital day before the start of diet in 127 patients who were suspected to have dysphagia. We performed statistical analyses to determine whether there was an association between aspiration pneumonia, these tests, and the combined screening method.
Eighteen patients (14.2%) developed aspiration pneumonia in the hospital. Significant risk factors for pneumonia were aging, male gender, and the severity of stroke on admission. SSPT was successfully performed in all patients, whereas WST failed to be completed in 14 patients (11.0%), 8 of whom developed pneumonia. An abnormal response to either SSPT or WST was significantly associated with pneumonia. In addition, multiple logistic regression analysis showed that an abnormal response to our combined screening method was an independent risk factor for pneumonia (p=0.012, odds ratio 9.79, 95% confidence interval 1.64–8.43).
Our combined screening method using both SSPT and WST is useful for the evaluation of swallowing in acute ischemic stroke patients, because it can be used for all patients with various underlying conditions.

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Balloon-mounted stent placement was performed for intracranial stenosis in 14 patients. The stenoses were located at the internal carotid artery petrous or cavernous portion (C45) in 10 patients, intracranial vertebral artery or basilar artery (VABA) in 3 patients and middle cerebral artery (MC) in 1 patient. MRI plaque image was observed in one patient. As a result, stenoses were improved by 65±20%. There were no ischemic symptoms after surgery in 13 patients. Restenosis was less than 50% in 12 patients. One patient who received a 3×15 mm stent in the basilar artery subsequently developed more than 50% stenosis and additional percutaneous transluminal angioplasty was performed. In one middle cerebral artery with placement of a 2.25×8 mm stent subsequently developed occlusion. The diameter of the vessel near stenosis was 3.9±0.7 mm in C45 stenoses, 3.0±0.3 mm in VABA stenoses and 2.2±0.2 mm in MC stenosis.
In conclusion, balloon-mounted stent placement was effective because sufficient dilatation of vessels was achieved, preventing further ischemia, especially in the petrous and cavernous portion. Stenosis less than 7 mm in length and more than 3 mm in diameter may be treatable using a balloon-mounted stent because the restenosis rate was not high. Vessel wall information will be useful using MRI plaque image.

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The objective of this study was to examine the clinical characteristics in very old patients suffering from acute stroke and to determine predictors of patient survival outcome in a regional hospital in which elderly patients with acute stroke are treated. Ninety-seven very old patients (> 79 years) with acute stroke admitted to the department of neurosurgery in our hospital were enrolled, and the association between patient outcome and several factors including age, sex, modified Rankin Scale (mRS) at discharge from the hospital, tube feeding at discharge and pneumonia during the hospitalization were analyzed by using Cox hazard model and log rank test. One-year survival of the 97 patients was 75%. Among them, patients younger than 85 years and those with mRS 0 to 3 resulted in a good outcome. Moreover, in 82 patients, excluding 15 patients who died during hospitalization, mRS 3 to 5, tube feeding and pneumonia were risk factors associated with patient death after discharge. Among them, pneumonia was the most significant and independent risk factor. Therefore, in very old patients with acute stroke, pneumonia during hospitalization as well as age and mRS may be important risk factors for predicting survival outcome. We should consider these factors when treatment after discharge is planned.

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Background and Purpose: In Japan, calcium antagonists have traditionally been prescribed for secondary prevention of stroke. However, the PROGRESS study, which showed the effectiveness of angiotensin converting enzyme inhibitors and diuretics to prevent stroke recurrence, should have influenced the selection of antihypertensive drugs. The purpose of this study was to survey the recent trends in the use of antihypertensive drugs for patients with stroke.
Methods: Among 2,153 patients with acute stroke in the Fukuoka Stroke Registry, 1,576 hypertensive patients were enrolled in this study. We studied stroke subtypes, prescribed antihypertensive drugs before admission and at discharge, and blood pressure levels at day 30 after admission.
Results: Antihypertensive drugs were prescribed to 860 patients (54.6% of enrolled patients) at discharge. Inhibitors of renin-angiotensin system (angiotensin converting enzyme inhibitor and angiotensin II receptor blocker) were most frequently prescribed (34.3%), followed by calcium antagonists (27.4%). Regarding 1,176 first-ever stroke patients, the most prescribed antihypertensive drugs before admission were calcium antagonists (64.9% of first-ever stroke patients with antihypertensive drugs) followed by inhibitors of the renin-angiotensin system (55.0%). However, inhibitors of the renin-angiotensin system were most frequently prescribed at discharge (66.7%) followed by calcium antagonists (47.7%). Blood pressure level at day 30 after admission showed good control level in all ages (systolic blood pressure range was 130–34 mmHg and diastolic pressure was 70–84 mmHg).
Conclusions: Our study revealed that inhibitors of the renin-angiotensin system are replacing calcium antagonists as the most preferable antihypertensive drugs for secondary prevention of stroke.

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The patient was a 43-year-old woman. She was brought to the hospital by ambulance with left hemiparesis, and cerebral infarction in the right cerebral hemisphere was observed on head MRI. Tubular stenosis in both internal carotid arteries near the first vertebral body was observed by cerebral angiography, and cerebral infarction caused by fibromuscular dysplasia (FMD) of the internal carotid arteries was diagnosed. Neurological symptoms gradually worsened despite anticoagulative treatment, and since MRI revealed enlargement of the cerebral infarction on the right cerebral hemisphere and a new cerebral infarction on the left cerebral hemisphere, percutaneous transluminal angioplasty (PTA) was performed on both internal carotid arteries. Worsening of neurological symptoms was not observed postoperatively, and although slight paralysis remained on the left side, she was discharged ambulatorily and was socially rehabilitated. Endovascular treatment that can be performed simultaneously on both sides was considered useful in a case such as this with internal carotid artery FMD causing progressive exacerbation. Angioplasty using only a balloon (POBA: plain old balloon angiography) is considered the first choice for FMD, but rupture or dissection of the intima occurs easily in POBA, and in such cases stenting is useful for rescue procedure.

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A 63-year-old woman presenting with a 6-month history of chorea was diagnosed with moyamoya disease. Cerebral angiography revealed occlusion of bilateral internal carotid arteries and net-like collaterals compatible with moyamoya disease. Single-photon emission computed tomography demonstrated diffuse hypoperfusion of the whole brain, including bilateral striatum. Chorea resolved without therapy. The disappearance of chorea may be explained by improvements in striatal ischemia due to formation of collateral arteries, or suppression of hyperexcitability in the pallidal inhibitory neurons with progression of pallidal ischemia.

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A 75 year-old female transported to hospital by heli-ambulance presented with disturbance of consciousness. She had been treated for hypertension, chronic atrial fibrillation, and chronic heart failure with an angiotensin converting enzyme (ACE) inhibitor (imidapril 10 mg/day). Examination on admission showed roving eye movement and right hemiparesis. NIHSS score was 35. Head magnetic resonance imaging (MRI) showed a fresh infarction in the left middle cerebral artery (MCA) territory. Magnetic resonance angiography showed the left MCA as defective downstream of the M2 portion. She was treated with 0.6 mg/kg intravenous alteplase at 103 minutes after onset. Shortly after recombinant human tissue-type plasminogen activator (rt-PA) thrombolysis, we found lingual swelling and she was intravenously treated with 500 mg of methylprednisolone. Her disturbance of consciousness and right hemiparesis improved (NIHSS score 16), but after 17 hours, her consciousness disturbance worsened again. Head MRI demonstrated a relapse of a brain infarction in the right MCA territory. Lingual angioedema completely disappeared after 36 hours. When a patient taking an ACE inhibitor is treated with intravenous rt-PA, it appears necessary to ascertain any orolingual angioedema, which can be difficult to find when limited to the tongue.

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A 67-year-old man was admitted to our hospital due to a sudden onset of unconsciousness and right hemiparesis. Acute basilar artery occlusion was suspected due to his clinical symptoms and the presence of atrial fibrillation on ECG. His brain CT scan demonstrated no abnormal findings 1 hr after the onset. The rapid improvement in consciousness and motor function, in addition to no occlusion and stenosis in major intra-cranial arteries on a 3D-CT angiography, suggested very early spontaneous recanalization of occluded vessels, and therefore, thrombolytic therapy was not indicated. Although he looked neurologically intact thereafter on the day of admission, he complained of blindness on the next day. He was diagnosed with cortical blindness because of acute bilateral posterior cerebral artery infarction on his brain MRI. The patient, on the day of admission, appeared to manifest Anton’s syndrome, a form of anosognosia in which patients do not realize their blindness. To take advantage of t-PA, prompt and precise evaluation of neurological symptoms needs to be done in all cases of acute cerebral infarctions. The current case is an example of the pit falls in diagnosing acute cerebral infarctions, and suggests the necessity of evaluating NIHSS even in cases in which early spontaneous recanalization of occluded vessels shows improvement of neurological symptoms and thrombolytic therapy is not indicated.

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A 66-year-old man was admitted due to internal and external ophthalmoplegia six days after developing headache and nausea. On gadolinium-enhanced magnetic resonance image, bilateral cavernous sinuses and superior orbital veins were not enhanced, which suggested cavernous sinus thrombosis. The left cavernous sinus contained an aneurysm of the internal carotid artery. Cerebral spinal fluid demonstrated pleocytosis of polymorphonuclear leukocytes and decreased glucose level, which suggested bacterial meningitis. After we started anticoagulants and antibiotics, the right cavernous sinus thrombosis and meningitis improved, but aneurysm of the left cavernous sinus enlarged and infectious aneurysms appeared on his cerebral cortex. Continuation of only antibiotics resulted in reduction of these aneurysms, but the left cavernous sinus thrombosis was not dissolved and left ophthalmoplegia remained. His sphenoid bone had defective areas on the upper wall, through which bacteria of sinusitis were assumed to have invaded and thrombosed the cavernous sinus. It was also assumed that bacterial thrombus influenced the meninges and internal carotid artery, thereby causing meningitis and aneurysm, which became an embolic source of infectious aneurysms on his cerebral cortex. Although cavernous sinus thrombosis is infrequent since the advent of antibiotics, it is necessary to pay attention to its development in people with defective sphenoid bone.

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