Peripheral arterial disease: Meta-analysis of the diagnostic performance of MR angiography

PURPOSE: To summarize the overall diagnostic performance of magnetic resona nce (MR) angiography in the evaluation of peripheral arteriosclerotic occlu sive disease and to identify the most important sources of variation in dia gnostic accuracy between studies. MATERIALS AND METHODS: A search strategy in MEDLINE and citation tracking w ere used to identify relevant English-language articles published since 199 1. Each article was critically appraised for examination, patient, and stud y design characteristics. The accuracy data from different studies were ana lyzed by constructing summary receiver operating characteristic curves; mul tiple linear regression was used to examine the variation between study res ults. RESULTS: Twenty-three studies were included. There was much heterogeneity i n the study results, which could not be explained as differences in the thr eshold for a positive result. About half of the variation was due to the ty pe of MR angiographic examination and the extent of image evaluation. The r elative diagnostic odds ratio (DOR) for three-dimensional (3D) gadolinium-e nhanced MR angiography compared with two-dimensional (2D) time-of-flight MR angiography was 7.46 (95% CI: :2.48, 22.20). The relative DOR for review o f transverse source images or multiplanar; reformations in addition to maxi mum intensity projections (MIPs) compared with the use of only MIPs for ima ge evaluation was 4.53 (95% CI: 1.46, 13.87). CONCLUSION: The diagnostic accuracy of 3D gadolinium-enhanced MR angiograph y is superior to that of 2D time-of-flight MR angiography. Also, the review of I transverse source images or use of additional postprocessing techniqu es, such as multiplanar reformation, results in significantly better diagno stic performance.