Time-resolved three-dimensional contrast-enhanced MR angiography of the peripheral vessels

PURPOSE: To compare the diagnostic accuracy of time-resolved-three-dimensional contrast material-enhanced-magnetic. resonance (MR) angiography with that of conventional angiography for imaging the lower extremity vasculature. MATERIALS AND METHODS: Sixty-nine patients who were evaluated for possible surgical intervention underwent conventional angiography (ie, digital subtraction angiography [DSA]) and, contrast-enhanced MR angiography (ie, time-resolved imaging of contrast kinetics [TRICKS]). Two independent, blinded readers evaluated vessel stenosis and occlusion at DSA and MR angiographic image readings. Sensitivity, specificity, positive and negative predictive values, and area under the receiver operating characteristic curve were analyzed with repeated-measures analysis of variance. The Cohen kappa test was performed to examine interreader variability. RESULTS: At pooled readings, contrast-enhanced MR angiography had a sensitivity of 78% and a specificity of 98% for detection of occlusion. For detection of significant stenosis (at least one greater than or equal to50% stenosis), sensitivity and specificity were 77% and 91%, respectively. interreader agreement was high for detection of both occlusion (kappa = 0.76) and significant stenosis (kappa = 0.68). Sensitivity increased as MR angiographic technical parameters were optimized. When improvements resulting from coil type and injection protocol were considered, the sensitivity and specificity of TRICKS MR angiography-were 89% and 97%, respectively, for occlusion detection and 87% and 90%, respectively, for significant stenosis detection. CONCLUSION: Contrast-enhanced TRICKS MR angiography is a feasible and minimally invasive means of acquiring angiograms of the peripheral vasculature with high sensitivity and specificity. (C) RSNA, 2002.