EXTRACRANIAL ATHEROSCLEROTIC CAROTID-ARTERY DISEASE - EVALUATION OF NON-BREATH-HOLD 3-DIMENSIONAL GADOLINIUM-ENHANCED MR-ANGIOGRAPHY

OBJECTIVE: The purpose of this study was to compare the diagnostic inf ormation provided by a combination of two-dimensional and three-dimens ional (3D) time-of-flight (TOF) techniques with that provided by non-b reath-hold 3D spoiled gradient-echo gadolinium-enhanced MR angiography . MATERIALS AND METHODS. Fifty patients suspected of having extracrani al atherosclerotic carotid artery disease were examined with all three imaging techniques using a 1.5-T MR imaging system. Three observers i ndependently and retrospectively measured the degree of stenosis accor ding to the North American Symptomatic Carotid Endarterectomy Trial cr iteria. The observers were unaware of the results of other MR imaging pulse sequences and digital subtraction angiography. The standard of r eference was established by digital subtraction angiography. Results w ere evaluated with receiver operating characteristic curve analysis. T he degree of interobserver agreement was determined using pairwise kap pa statistics. RESULTS. The grading of carotid artery stenosis as meas ured by the area under the receiver operating characteristic curve was less accurate with non-breath-hold 3D gadolinium-enhanced MR angiogra phy than with TOF imaging. Interobserver variability was greater for n on-breath-hold 3D gadolinium-enhanced MR angiography than for TOF tech niques. CONCLUSION. Routine evaluation of carotid artery stenosis at t he level of the bifurcation using non-breath-hold 3D gadolinium-enhanc ed MR angiography is less accurate than is TOF imaging and is therefor e not recommended. The weakness of this technique may be due to proble ms in timing the injection of gadolinium and the masking of the caroti d bifurcation by the venous jugular system.