Particulate emboli retained by a screen and a depth transfusion filter. A SEM study.

Microembolization by platelet leukocyte aggregates is a threat to the pulmonary microvasculature when blood is transfused to patients. Those aggregates can be removed by filters (either depth filter or screen filter); their efficiency, as shown by SFP measurements is not questionable, however they are working in different ways as observed by SEM: mechanical retention and adsorption.