The authors have reviewed the clinical records of 110 patients with intracranial cavernous malformations diagnosed by histological examination and/or magnetic resonance imaging over a mean follow-up period of 4.71 years. These cases were divided, based on their presentation, into a hemorrhage group, a seizure group, and an incidentally diagnosed group. The rate of subsequent symptomatic bleeding was investigated in relation to age at onset, sex, and location of the initial lesion. A high rate of subsequent symptomatic bleeding episodes was found in the hemorrhage group, especially among younger females. The nonhemorrhagic-onset cases had a very low incidence of bleeding. The outcome was generally good, except in patients with lesions in the basal ganglia and brainstem. These findings will be helpful in planning a rational therapeutic strategy for intracranial cavernous malformations.

The correlation of magnetic resonance imaging (MRI) with histopathological findings was analysed in 26 patients with untreated cerebral gliomas. In low-grade gliomas, T2-weighted images demonstrated relatively homogeneous high-intensity lesions involving both the grey and the white matter. In high-grade gliomas, especially grade IV, T2-weighted images demonstrated prominent heterogeneity in signal intensity, which consisted of a hyperintense "core", less hyperintense or normal intensity "rim" and surrounding finger-like areas of high intensity. Marked and irregular contrast enhancement was evident in all but one case of these high-grade gliomas in which gadolinium-DTPA was used. Histological examination revealed tumour cells extending as far as the borders of the high-intensity areas shown on T2-weighted images in both high- and low-grade gliomas, but in 5 of 8 low-grade and 4 of 18 high-grade gliomas, isolated tumour cells extended beyond the hyperintense areas shown on T2-weighted images.

There has been a growing evidence for the existence of magnetic fields in the extra-galactic regions, while the attempt to associate their origin with the inflationary epoch alone has been found extremely challenging. We therefore take into account the consistent post-inflationary evolution of the magnetic fields that are originated from vacuum fluctuations during inflation. In the model of our interest, the electromagnetic (EM) field is coupled to a pseudo-scalar inflaton φ through the characteristic term φFF , breaking the conformal invariance. This interaction dynamically breaks the parity and enables a continuous production of only one of the polarization states of the EM field through tachyonic instability. The produced magnetic fields are thus helical. We find that the dominant contribution to the observed magnetic fields in this model comes from the modes that leave the horizon near the end of inflation, further enhanced by the tachyonic instability right after the end of inflation. The EM field is subsequently amplified by parametric resonance during the period of inflaton oscillation. Once the thermal plasma is formed (reheating), the produced helical magnetic fields undergo a turbulent process called inverse cascade, which shifts their peak correlation scales from smaller to larger scales. We consistently take all these effects into account within the regime where the perturbation of φ is negligible and obtain B eff ∼ 10 −19 G, indicating the necessity of additional mechanisms to accommodate the observations.

SUMMARY The dolichoectatic basilar artery was found in 23 cases during a 10-year period. The 19 males and 4 females ranged in age from 30 to 69 years (mean: 55 years). Hypertension was noted in 17 patients. In seventeen (74%) of the present cases this anomaly could be visualized with CT scan. Seven patients (30%) presented with pontine infarction, which was identified on CT scan in all cases. Vertebro-basilar insufficiency was found in four patients. One patient had transient ischemic attacks. There were facial spasms in four patients and impairment of the lower cranial nerves in one. One patient exhibited cerebellar hemorrhage. In two patients this anomaly was found incidentally. Associated intracranial aneurysms were identified in seven patients, including fusiform aneurysms in 4 and saccular aneurysms in 3. Three patients had an accompanying hydrocephalus. The dolichoectatic basilar artery is associated with various consequences especially in relation to the pathogenesis of brainstem infarction. When this anomaly is diagnosed by CT findings, even if it is clinically asymptomatic, it may be better to treat these patients with medical therapy used to prevent ischemic stroke.

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