Prospective evaluation of peripheral arterial occlusive disease by 2D MR subtraction angiography

The purpose of this study was to assess the diagnostic value of two-dimensi onal (2D) MR subtraction angiography of lower extremities in patients with symptomatic peripheral arterial occlusive disease with conventional angiogr aphy as the standard of reference, Twenty patients were prospectively inclu ded. 2D subtraction MR angiography (MRA) consisted of multisection gradient -recalled echo (GRE) acquisitions with the shortest TE available on our mac hine (4 msec), obtained in the coronal plane before and after intravenous b olus administration of gadolinium chelate. MR images were reconstructed aft er subtraction with a maximum-pixel-intensity-projection (MIP) algorithm. M RA was performed in all cases 1-4 days before diagnostic angiography. In a prospective blinded analysis, the number and location of significant tie, > 50% stenoses and occlusions were evaluated for each vascular segment. Sensi tivity and specificity were used to evaluate MRA data. Significant stenoses (38 of 46, 83%) and occlusions (66 of 67, 99%) seen at conventional angiog raphy were identified with MRA The sensitivity and specificity of MRA for d etermination of stenoses >50% or occlusions was 100% and 97%, respectively. The location and extent of stenoses and/or occlusions on MRA and angiogram s were well correlated (kappa values, r = .73, P < .05), Contrast 2D MR sub traction angiography, by providing comparable information to that of conven tional angiography, is well suited to evaluate the presence and severity of atherosclerotic lesions of the lower limbs.