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In ischaemic stroke, expansion of the infarct core occurs at the expense of surrounding hypoxic, metabolically compromised tissue over a period of 24 h or more in a considerable proportion of patients. It is uncertain whether hypoxic tissue observed at later times after stroke onset retains the potential for survival or whether such survival has an impact on functional outcome. These factors may determine the effectiveness of therapeutic strategies aimed at salvaging this tissue. We tested the hypotheses that metabolically compromised hypoxic tissue observed within 48 h after onset of ischaemic stroke retains the potential for spontaneous survival and that the impact of such survival on functional outcome is time dependent. Consecutive patients presenting within 48 h of ischaemic stroke were studied with [18F]fluoromisonidazole, a ligand binding to hypoxic but viable tissue, and PET. Subjects were grouped into two time epochs, ≤12 and >12 h, based on the interval from stroke onset to the time of tracer injection, and had infarct volumes measured on CT/MRI at 7 days (n = 60). The total ischaemic volume (TIV) and the proportion of the TIV that spontaneously survived (surviving hypoxic volume ratio, SHVR) were defined from the co‐registered CT/MRI images. These volumetric measures were correlated with neurological outcome assessed at day 7–10 by percentage change in the National Institutes of Health Stroke Scale (ΔNIHSS), and at 3 months by Barthel Index (BI) and modified Rankin Score (mRS). Of 66 patients investigated, hypoxic tissue occurred in 33 and outcome data was available in 27. Hypoxic tissue constituted >20% of the TIV in 60% of studies ≤12 h and 16% >12 h. The spontaneously surviving proportion of the TIV (median 6.9%) or hypoxic tissue (median 45.9%) was not significantly different in patient subgroups studied ≤12 or >12 h after stroke onset. Spontaneous survival of hypoxic tissue (surviving hypoxic volume ratio) was associated with improved neurological outcome in both time epochs: ≤12 h, ΔNIHSS (r = 0.85, P < 0.01), day 90 BI (r = 0.86, P < 0.01) and day 90 mRS (r = –0.89, P < 0.01); >12 h, ΔNIHSS (r = 0.59, P < 0.01) and day 90 mRS (r = –0.46, P < 0.05). The finding that similar proportions of hypoxic tissue survived spontaneously within each time epoch suggests that its fate is not predetermined. The favourable neurological outcome associated with spontaneous survival of hypoxic tissue, even 12–48 h after stroke onset, suggests that the volume of hypoxic tissue that progressed to infarction may represent a valuable target for therapeutic intervention.

Objective:Since little is known concerning factors which may influence long-term prognosis of patients presenting with lacunar stroke, we conducted a longitudinal study of this stroke subtype. Variables likely to affect outcome were assessed at baseline, including those from transoesophageal echocardiographic studies. Methods:Consecutive patients presenting with first-ever lacunar stroke underwent diagnostic workup that included brain CT or MRI, carotid duplex, and transthoracic and transoesophageal echocardiography. An assessment of patients was planned at entry (baseline), and thereafter every 12 months (clinic visit or telephone call), drop-out, or endpoint. The primary endpoint was nonfatal or fatal stroke. Secondary endpoint was death due to any cause. Results:Among 60 consecutive lacunar patients with the mean follow-up period of 3.9 years, 12 patients (20%) had stroke recurrence. The mean annual rate for stroke was 5.2%, and for death 2.8%. For multivariate Cox proportional hazards analysis, the following three variables with the values of p < 0.1 after univariate testing were chosen: age (p = 0.095); aortic atheroma (p = 0.066); and any source of embolism from heart (p = 0.007). Any source of embolism from heart was the only factor which significantly enhanced the risk of stroke recurrence (p = 0.015). Using Kaplan-Meier life table analysis, the curves of percent free of recurrent stroke were significantly different (log rank test p = 0.002). Conclusions:Until the mechanism of lacunar stroke is better understood, it is reasonable to suggest that its investigation and prevention should be directed at all potential causes of future strokes including cardioembolism.

We describe a patient with a cerebral infarction localized mainly in the left posterior frontal and anterior parietal subcortices who experienced a Broca's aphasia which evolved into a conduction aphasia. Such a rare recovery pattern of aphasia appeared to result from amelioration of the damage to the left precentral gyrus.

Sequential gadolinium-DTPA (Gd-DTPA) enhanced MR images were obtained before and after steroid therapy in a case of neuro-Behçet's disease. Multiple scattered lesions, which could not be detected on pre-and post-contrast CT, were demonstrated mainly in the white matter of the pons and/or the cerebrum with both T1-and T2-weighted images. Some of these lesions, however, were not enhanced at all by infusion of Gd-DTPA. The Gd-DTPA infusion study demonstrated marked enhancement in the white matter of the pons and cerebrum. Some lesions not seen with T2-weighted images were also strongly enhanced by Gd-DTPA infusion at the acute stage. After steroid therapy, the symptoms and abnormal laboratory findings were resolved. The pontine and cerebral lesions on plain MR images remained unchanged even after resolution of the symptoms, suggesting that they were inactive old foci. On the other hand, the lesions detected in the enhancement study before steroid therapy disappeared with the repeat Gd-DTPA enhanced MR images which were performed after resolution of the symptoms. Some active inflammatory lesions in, neuro-Behçet's disease may be demonstrated only on Gd-DTPA enhanced MR images. Gd-DTPA enhanced MR imaging appears to be potentially useful for detecting active inflammatory lesions in neuro-Behçet's disease and for evaluating the efficacy of treatment.

A 58‐year‐old man with intravascular malignant lymphomatosis initially developed myeloradiculopathy without cerebral symptoms. His MRI, however, demonstrated solid, wedge‐shaped, and well‐demarcated lesions in the deep white matter and a string‐shaped lesion along with nerve fibers in the splenium of corpus callosum. A variety of cerebral symptoms manifested a month afterward. The possibility of this disease should be considered in cases of undiagnosed myeloradiculopathy with such silent brain lesions.

To reassess the independent risk factors for lacunar stroke and to clarify the role of potential embolic sources, we conducted a case-control study using transesophageal echocardiography and duplex ultrasonography. Among 62 consecutive patients with their first lacunar stroke and 202 normal controls, we found that hypertension (p< 0.001), smoking (p0.001), and aortic arch atheroma (p0.006) were independently associated with an increased risk of lacunar stroke. Whether proximal aortic arch atheroma is mechanistically associated with lacunar stroke or merely coexistent is uncertain.

In 80 patients with no stenotic lesions in the vertebrobasilar arterial system, a study was made of the relationship between the deviation of the basilar artery (BA) from the midline on computed tomography (CT) and the right-to-left vertebral arterial caliber difference on angiograms. In 66 patients (83%), the BA was visible on plain CT films, and 55 of them showed deviation of the BA to either side. In 44 of these patients (80%), the vertebral artery (VA) contralateral to the side of BA deviation had a larger caliber compared with the ipsilateral one on angiograms. In 6 patients whose unilateral VA terminated in the posterior inferior cerebellar artery (PICA) and showed an extremely small caliber compared to the contralateral one, the BA was always deviated to the side of the smaller VA. Our data suggest that the deviation of the BA on plain CT films may represent a good indicator for estimating the right-to-left VA caliber difference. At the time of vertebral angiography, injection of contrast medium should preferably be made from the larger VA in order to avoid laminar flow in the BA and to shorten the procedure. Prior estimation of the right-to-left VA caliber difference by CT may be of great benefit to the angiographic procedure.

We describe a patient with a cerebral infarction localized mainly in the left posterior frontal and anterior parietal subcortices who experienced a Broca's aphasia which evolved into a conduction aphasia. Such a rare recovery pattern of aphasia appeared to result from amelioration of the damage to the left precentral gyrus.