Magnetic resonance scans of 74 patients with multiple sclerosis participating in a controlled trial were compared 6 months before and at the end of a 24-32 months-treatment period with either Cyclosporin A (n = 31) or Azathioprine (n = 43). Both qualitative rating and computation of lesion volume showed deterioration in more than 40% of the patients, while by clinical criteria only 10-30% were worse. No significant difference was noted when the two treatment groups were compared. If careful repositioning and standardized image parameters are used, MRI is an indispensable tool for the objective determination of disease progression in MS although it cannot replace clinical examination.

The volumes of intracranial arachnoid cysts were measured in 136 CT scans of 86 patients. Absolute and relative cyst size was calculated. Left hemisphere and middle cranial fossa location prevailed. A slight negative correlation of relative cyst size with age (r = -0.21, NS) disappeared when analysis was restricted to the adult age group (greater than or equal to 20 years). After the sample was divided into two groups according to relative cyst size (cysts less than mean volume vs cysts greater than mean volume), small AC showed no correlation with age, while large AC correlated positively with age (r = 0.79, P less than 0.05). A subgroup of large AC appears to expand with time, while the majority of small AC remain unchanged.

No abstract

Malignant melanoma of the meninges is a rare neoplasm derived from melanocytes of the cranial or spinal meninges. Histologically classified as grade IV tumours, malignant melanoma may present either as a diffuse meningeal neoplasm, first described by Virchow in 1859, or as a circumscribed tumour attached to the meninges. Although diagnosis is rarely established prior to surgery or autopsy, MR and CT may provide indispensable information probably leading to earlier diagnosis. In 4 patients, diagnosis of a primary meningeal melanoma was based on MR and CT findings and histology. Histology was obtained in 3 cases by surgery, in one patient by autopsy and showed a melanotic and an amelanotic malignant melanoma in 2 patients each. Autopsy was carried out in 3 cases after survival of 4, 5, and 18 months; in a single case, the follow-up period is almost 3 years.

A case of cerebral air embolism from a rather unusual cause is reported; an esophago-cardiac fistula permitted food particles and air to enter the systemic arterial circulation. Massive embolization caused the patient to become deeply comatose rather suddenly. The computed tomogram (CT) revealed massive cerebral edema with the contradictory finding of wide superficial subarachnoid spaces. These subarachnoid spaces on further evaluation proved to be air in the cerebral vessels.