BALLOON OCCLUSION SCINTIGRAPHY OF AORTOPULMONARY COLLATERALS

We evaluated two children with pulmonary atresia for coil embolization of aortopulmonary collateral vessels after placement of palliative ao rtopulmonary shunts. To determine vessel distribution and lung perfusi on prior to collateral embolization, perfusion scintigraphy with techn etium 99m-labeled macroaggregated albumin assessed pulmonary blood flo w before and after balloon wedge catheter occlusion of the collaterals . In the first patient we found no perfusion defect during collateral occlusion, and we proceeded with embolization. In the second child, pe rfusion scintigraphy during occlusion of the collateral vessels demons trated a filling defect, and embolization was not performed, thus avoi ding the creation of a potential perfusion defect in this patient. Ass essing the physiologic significance of aortopulmonary collateral vesse ls by utilizing temporary balloon occlusion of the collateral vessels and concurrent perfusion scintigraphy as an adjunct to selective angio graphy can provide a significant contribution to the safety and accura cy of coil embolization.