Cardiotomy suction: a major source of brain lipid emboli during cardiopulmonary bypass.

Background: Brain injury remains a significant problem in patients undergoing cardiac surgery assisted by cardiopulmonary bypass (CPB). Autopsy brain specimens of patients after cardiac operations with CPB reveal numerous acellular lipid deposits (10 to 70 microm) in the microvasculature. We hypothesize that these small capillary and arterial dilatations result from a diffuse inflammatory response to CPB or from emboli delivered by the bypass circuit.

Cerebral microvascular alterations in aging, leukoaraiosis, and Alzheimer's disease.

We have been using alkaline phosphatase (AP) histochemical staining, formerly a research tool for the study of cerebral cortical vascular morphology, to examine pathological changes in the cortex and deep cerebral structures. Deep structures stain similarly to the cortex. The AP stain is found in the afferent vessels (small arteries, arterioles, and capillaries), but not in venules and veins.

Human germinal matrix: venous origin of hemorrhage and vascular characteristics.

Purpose: To examine the vascular supply and architecture of the germinal matrix in the preterm neonatal brain and to determine whether veins or arterioles are the source of germinal matrix hemorrhage.

Methods: Brains from eight preterm neonates (24 to 35 weeks' gestation) and two full-term infants were fixed in alcohol, embedded in celloidin, sectioned at 100- and 500-micron thicknesses, stained for alkaline phosphatase, and examined with light microscopy. High-resolution contact radiographs of 500-micron-thick sections were also mounted on glass slides for microscopic examination.