MICROVASCULATURE IN GERMINAL MATRIX LAYER - ITS RELATIONSHIP TO GERMINAL MATRIX HEMORRHAGE

Microvasculature in the germinal matrix layer (GML) was studied by postmortem microangiography and stereomicroscopic observation on cleared specimens in methyl salicylate. A number of arterioles from penetrating and medullary branches of main cerebral arteries were distributed in the GML, forming a fine network of arterioles anastomosing with each other. Many venules in the GML converged at a few points and drained into subependymal veins. The main converging zone of venules was situated inside the GML close to the border zone of the GML and adjacent cerebral parenchyma. The converging zone coincided with the site of GML hemorrhage. Thus, many factors, including both venous and arterial, appear to influence circulation in the GML; ultimately the converging zones become overloaded and rupture, leading to GML hemorrhage.