ROUTINE ANGIOGRAPHY AFTER SURGERY FOR RUPTURED INTRACRANIAL ANEURYSMS- A COST VERSUS BENEFIT ANALYSIS

PURPOSE: To assess the cost versus the benefit of routine cerebral ang iography after surgery for ruptured aneurysms. METHODS: Decision tree and Markov analyses that used cohort simulation were conducted to dete rmine the incremental cost:benefit ratio of routine postsurgical angio graphy. Input data for unexpected partially clipped and unclipped cere bral aneurysms were estimated from the literature for the following va riables: frequency; annual rate of subsequent hemorrhage; morbidity an d mortality rates of subsequent hemorrhage; efficacy and morbidity and mortality rates of subsequent surgery; and costs of subsequent surger y, angiography, subsequent hemorrhage of aneurysm, and rehabilitation. RESULTS: Baseline input variables resulted in an acceptable cost:bene fit ratio for routine postsurgical angiography. However, essentially a ll of the benefit was derived from intervening in cases of unexpected unclipped aneurysms rather than partially clipped aneurysms. Isolated instances of angiography and subsequent surgery for unexpected partial ly clipped aneurysms yielded unacceptable cost:benefit ratios. Surgica l costs had minimal effect on the analysis. CONCLUSIONS: When routine postsurgical angiography was performed primarily to diagnose and to su bsequently operate on unexpected partially clipped aneurysms, the cost :benefit ratio was unacceptable. However, even low frequencies of unex pected unclipped aneurysms resulted in favorable cost:benefit ratios.