Dynamic cisternography in normal dogs and in human beings.

Cisternography and ventriculography were performed in five normal anesthetized dogs to study the dynamics of tracer dispersal. Indium 111-diethylenetriaminepentaacetic acid was injected into lateral ventricles, cisterna magna, thoracic subarachnoid space, and lumbar sac. The patterns of dispersal from each injection site support a nonflow dispersal mechanism with a tendency toward ultimate equilibrium distribution throughout the cerebrospinal fluid. Quantitative data in humans complement observations made in dogs. A theory of abnormal tracer movements, based on factors observed to affect tracer dispersal in dog and man, is proposed and applied to the interpretation of abnormal cisternographic patterns seen in clinical situations.