Cost-effectiveness of nuclear medicine procedures in renovascular hypertension.

The role of nuclear medicine in the differential diagnosis of renovascular hypertension (RVH) has been a highly controversial one. The reason for this rests with the lack of specificity of this test in screening for RVH. Although renography is very sensitive in detecting unilateral renal disease, it is nonspecific and an unacceptable number of false-positives occur. Recently the introduction of captopril renography has provided a new stimulus for reevaluation of this test in the differential diagnosis of renovascular disease. In spite of prevailing opinion, a careful review of the relative cost of renography and digital subtraction angiography (DSA) demonstrates that there is a role for renography in this differential diagnosis at all stages of investigation. Routine renography, when interposed between DSA studies, significantly reduces the cost per case of RVH found. If captopril renography proves as specific as is theoretically possible, the cost reductions achieved can be even greater. There is a significant and cost-efficient role for renography in the differential diagnosis of RVH. In addition to its reduction of cost in case finding, renography also avoids the risk of contrast media administration in a significant number of patients by reducing the population for screening to those at very high risk of disease.