DIGITAL SUBTRACTION VERSUS FILM-SCREEN ANGIOGRAPHY FOR DETECTING ACUTE PULMONARY EMBOLI - EVALUATION IN A PORCINE MODEL

PURPOSE: To compare the diagnostic performance of digital subtraction angiography (DSA) to that of film-screen angiography (FSA) for detecti ng acute pulmonary embolism (PE) in a porcine model. MATERIALS AND MET HODS: DSA and FSA were performed in 13 pigs before and after central v enous administration of autologous emboli, Results were compared to fi ndings at necropsy with use of ex vivo pulmonary angiography to guide pathologic sectioning. The sensitivity and predictive value of a posit ive case for detecting each embolus were computed for each pulmonary a rtery branch order and compared with use of 95% confidence intervals, Interobserver variability among three readers for individual PE detect ion was calculated. RESULTS: Pathologic examination of the lungs revea led 100 total PEs (location by vessel order: 1st = 1, 2nd = 0, 3rd = 1 5, 4th = 32, > 5th = 52). On average, FSA review identified 72 (72%) e mboli and DSA review, 65 (65%), There was no significant difference in sensitivity or predictive value of a positive case between DSA and FS A for detecting emboli (P > .05), There was similar agreement among re aders for individual PE detection with DSA (mean, 84%) and FSA (mean, 80%). CONCLUSION: The diagnostic performance of DSA is equivalent to t hat of FSA for detecting emboli in porcine PA branches. Interobserver agreement for individual PE detection is similar for both imaging tech niques.