Fate of red blood cells injected into cerebrospinal fluid pathways

Abstract

The distribution of tagged red blood cells injected into the cisterna magna of dogs has been studied. Our findings indicated that, of the total injected dose of erythrocytes, approximately 25% is absorbed directly into the blood stream in an intact state. Insignificant hemolysis occurs. The remaining 75% of the injected red cells become enmeshed and fixed in the arachnoid. This experimental finding may explain the occurrence of communicating hydrocephalus following sub-arachnoid hemorrhage by obstruction of the normal absorptive mechanism.