Hirotoshi Sumie

Middle Fossa Arachnoid Cyst: Clinical, Neuroradiological, and Surgical Features

16 patients and 4 adult cases of small-or medium-sized middle fossa arachnoid cyst were subjected to various neuroradiological investigations and their results were analyzed in terms of possible mechanisms of cyst expansion. Based on the results of the investigations which strongly suggested that the cyst is an expanding lesion, all cases were surgically treated by the same techniques of craniotomy, excision of the outer cyst membrane, followed by a cystoperitoneal shunt, resulting in complete disappearance of the cyst concomitant with reexpansion of the surrounding brain and marked improvement in the clinical pictures of the patients.

MRI findings in the mild type of mucopolysaccharidosis II (Hunter's syndrome)

SummaryNeuroradiological findings in a 44-year-old male with the typical mild type of Hunters disease are reported. Cranial MRI revealed patchy areas of increased and decreased signals in T1- and T2-weighted images in the thalamus and the basal ganglia giving rise to a honey comb-like appearance as a whole. The deep white matter showed high signals in the T2-weighted image. To our knowledge, the honey comb-like appearance has never been reported in this disorder. Deposition of mucopolysaccharides and/or glycolipids and increase in fluid content seem to be responsible for these changes.

Cervical radiculomyelopathy due to calcification of the ligamenta flava

Three cases of cervical radiculomyelopathy caused by calcification of the ligamenta flava of the cervical spine are reported. A review of the literature yielded 13 cases of calcification of the cervical ligamenta flava with findings similar to those in our cases. Specifically, we observed that 1) all patients were more than 50 years of age; 2) most were female; and 3) the calcifications appeared consistently as oval nodules, located symmetrically and paramedially in and around the region of the fifth cervical vertebra. Such characteristic similarities in both clinical and radiologic features are important in considering the etiology of calcification of the cervical ligamenta flawa.

Surgically confirmed myelographic classification of congenital intraspinal lipoma in the lumbosacral region

Twenty-four cases of histologically confirmed congenital intraspinal lipoma of the lumbosacral region were studied by means of myelography with metrizamide. The findings were compared with intraoperative observations. Myelography with metrizamide clearly revealed the detailed intrathecal structures and allowed a classification of intraspinal lipomas into four types, in terms of their insertion into the conus medullaris: (1) dorsal type, either with direct or indirect (via an intrathecal stalk) insertion of the extrathecal lipoma into the dorsal aspect of the conus medullaris; (2) caudal type; (3) combined type; and (4) filar lipoma. Based on our surgical experience in untethering and decompression of the lesions, the classification was found to be useful in designing a safe and effective surgical procedure which minimized all possible trauma to the intrathecal neural structures.

Ammon’s Horn Sclerosis on Pneumoencephalotomography

Fourteen cases with psychomotor seizure were examined by pneumoencephalotomographic technique. In all cases uni- or bilateral changes of the inferior horn were found: diverticular dilatation of subiculum, lowering and irregularity of the floor, reduction of width, and deformation of digitation. These findings correlated well with the autopsy reports. In most cases, EEG findings also correlated.

Basiparallel Cut by Pneumoencephalotomography and Cerebellar Atrophy

The basiparallel cut is a nearly horizontal slice of the posterior fossa used in air study and the structures are observed on a plane parallel to the clivus. Total shrinkage of the cerebellum, with or without fourth ventricle dilatation, was found in cases of olivopontocerebellar atrophy, some intoxications, and a few senile subjects. Some atrophy of paleocerebellar portions was seen in Holmes-type degeneration. Another pattern was symmetric shrinkage of neocerebellar lobules and relatively specific for the cases of ‘multiple system atrophy’ such as progressive supranuclear palsy, striatonigral degeneration, Marie’s ataxia, etc. Loss of the superior cerebellar peduncle was clearly demonstrated in this view.