No abstract

A specific group of intrinsic dorsal midbrain tumors was identified in six children by computerized tomography (CT) and magnetic resonance (MR) imaging. Each patient presented with raised intracranial pressure as a result of hydrocephalus due to obstruction of the sylvian aqueduct. No patient had brain-stem signs referable to the tectal tumor initially or subsequently. All six children underwent cerebrospinal fluid (CSF) diversionary procedures. The radiological features were consistent and specific, with all patients showing tectal calcification or primary increased attenuation of the tectal plate on CT scans. In addition, lack of contrast enhancement was noted initially in four patients and eventually in all six patients. In all patients MR imaging showed a focal tectal tumor distorting the collicular plate with no cystic component and increased signal intensity on T2-weighted images. There has been no evidence of progression in these six patients in the follow-up period ranging from 8 months to 17 years (8 months and 2 1/2, 4 1/2, 8, and 17 years). Diversion of CSF has been the only surgical treatment and no patient underwent deep x-ray therapy. Five patients have had normal intellectual development. In contrast to the majority of previously described periaqueductal and tectal tumors, this group of lesions appeared to be truly benign. The authors suggest that patients presenting with these clinical and radiological features may be managed by CSF diversion, serial examination, and MR imaging.

The increasing sophistication of neuroradiology has significantly and progressively improved the diagnosis of diastematomyelia in 172 children presenting at the Hospital for Sick Children, Toronto, over a 40-year period. Standard radiography, computed tomography and magnetic resonance imaging are all necessary to accurately assess all the facets of this most interesting of spinal cord anomalies.

The findings at autopsy were correlated with the computed tomographic (CT) diagnosis in 90 neonates that had suffered perinatal hypoxia and had CT within 10 days before autopsy. CT was accurate in the diagnosis of supratentorial hemorrhage whether it was subependymal, intraventricular, or intracerebral. Infratentorial hemorrhage was difficult to detect or localize with accuracy. Correlation between areas of hypodense brain tissue seen on CT and areas of ischemic brain damage other than hemorrhage at autopsy was poor. Diagnosis of generalized cerebral edema by CT, however, was very good.

The imaging of craniopharyngioma may include plain skull x-rays, computer tomography (CT) scans, magnetic resonance imaging (MRI) and angiography. Coronal studies are essential to properly define the regional anatomy. The solid or cystic character of the lesion is especially apparent with contrast enhancement. MRI adds a sagittal projection which is useful, and its increasing sophistication may eventually make angiography superfluous in these tumours. The appearance of craniopharyngiomas in each modality is described, including 3D, and an ideal imaging strategy presented. Postoperative imaging is best done with both MRI and CT, and enhanced studies done within 48 h to avoid the effect of surgical trauma.