Toshinori Yamashita

Estimation of rate of growth of malignant brain tumors by computed tomography scanning

The growth rate of malignant gliomas was estimated by serial computed tomography scanning. The actual tumor doubling time was determined by calculating the change in tumor volume on the scans. Eleven malignant gliomas were assessed by this method. The actual tumor doubling times of malignant gliomas ranged from 15.0 to 21.1 days, averaged 19.5 +/- 1.9 days, and showed no significant variation according to histopathologic differences. By determining the tumor doubling time in this manner, the growth rate of a tumor can be assessed. The efficacy of treatment and subsequent prognosis in malignant brain tumors can be predicted more accurately by estimation of the growth rate. The clinical application of the growth rate of malignant gliomas is presented.

Thermosensitive Determination of Patency in Lumboperitoneal Shunts: Technical note

Surface cooling and thermistor recording over shunt tubing was used in 23 studies of cerebrospinal fluid shunt patency in 19 patients with lumboperitoneal shunts and normal-pressure hydrocephalus. Shunt patency was shown by downward reflection of the recording trace similar to that obtained for ventriculoperitoneal shunts. Obstruction was demonstrated by a flat-line recording or an upward deflection.