Brain tumors in the first 2 years of life in Saudi Arabia.

Thirty-four patients with brain tumors were diagnosed and treated during the first 2 years of life, representing 8% of the 273 children treated for primary brain tumors from 1981 to 1990 inclusive. Large head circumference, vomiting, and altered level of consciousness were the chief findings at the time of presentation. Overall, the tumors were located mainly supratentorially; in patients in the 1st year of life they were equally distributed above and below the tentorium, while two-thirds of the patients presenting in the 2nd year of life had supratentorial tumors. The most common histological types were astrocytomas and medulloblastomas. Treatment methods were ventricular peritoneal shunt, craniotomy with total or partial removal of the tumor, adjuvant radiotherapy, and in a few cases chemotherapy. The 2-month mortality rate was 5.9%. The follow-up period ranged from 3 to 50 months.

The parenchymal CT myelogram: in vivo imaging of the gray matter of the spinal cord.

Past attempts to visualize the internal structure of the spinal cord in vivo have been hampered by many factors, including the small size of the cord, the dense bony investiture of the spine, and the similarities of tissue densities from one region to another within the cord. Delayed CT is the imaging technique currently being used at our institution as an adjunct to iopamidol myelography to visualize the deep gray matter of the cord. This visualization is achieved by a poorly understood differential gray/white-matter enhancement, possibly due to either a shielding effect of the white matter as it envelops the gray matter, a differential absorption rate between gray and white matter, or a greater rate of reabsorption of contrast by the more highly vascularized gray matter. This method is not being advocated as a primary diagnostic technique due to the lack of reliability in providing successful results from section to section, from patient to patient, and from one time period of delay to the next. Instead, it is an initial attempt to image the basic, intrinsic structure of the spinal cord in vivo, which may herald a valuable advance in imaging methodology.