Partial Splenic Embolization with Y-Shaped Silicone Particles

We have developed an embolizing material consisting of Y-shaped silicone particles for partial splenic embolization. Wide spaces for blood flow are left around the particles when these are lodged in arterial branches. We embolized one kidney in each of 3 dogs with the particles and observed a slowly induced occlusion of renal arterial branches during one month. The particles were also used for partial splenic embolization in 14 patients. The average portion of infarcted spleen tissue 7 days after embolization was 51% calculated from CT images. In 6 patients who had CT both 2 and 7 days after embolization, the average rate of splenic infarction increased from 29% at 2 days to 60% at 7 days. Our patients required analgesics for only 2.3 days on average. The Y-shaped silicone particles by slowly occluding splenic arterial branches produce ischemia in a gradual fashion which may minimize the pain after embolization.