Evaluation of cerebral aneurysms with high-resolution MR angiography usinga section-interpolation technique: Correlation with digital subtraction angiography

BACKGROUND AND PURPOSE: The objective was to evaluate the results of high-r esolution, fast-speed, section-interpolation MR angiography and digital sub traction angiography (DSA), thereby examining the potential use of a primar y noninvasive screening test for intracranial aneurysms. METHODS: The images were obtained in 39 cerebral aneurysmal lesions from 30 patients with a time-of-flight MR angiographic technique using a 1.5-T sup erconducting MR system. The total image volume was divided into four slabs, with 48 partitions each. To save time, only 24 phase-encoded steps were me asured and interpolated to 48, The parameters used included 30/6.4 (TR/TE), a flip angle of 25 degrees, a 160 x 512 matrix, a field of view of 150 x 2 00, 7 minutes 42 seconds of scan time, an effective thickness of 0.7 mm, an d an entire thickness of 102.2 mm. Maximum intensity projection was used fo r the image analysis, and a multiplanar reconstruction technique was used f or patients with intracranial aneurysms. RESULTS: Among 39 intracranial aneurysmal lesions in 30 patients, 21 were r uptured and 18 were unruptured. Twelve lesions were less than 2 mm in size, 12 were 3 to 5 mm, 12 were 6 to 9 mm, and three were larger than 10 mm. At initial examinations, 38 of 39 aneurysmal lesions were detected by both MR angiography and DSA, with 97% sensitivity. In confirming aneurysms in neck and parent vessels, multiplanar reconstruction was successful in detecting all 39 aneurysms, whereas MR angiography was successful in detecting 27 (6 9%) and DSA was successful in detecting 32 (82%) of the lesions. CONCLUSION: High-resolution MR angiography with a section-interpolation tec hnique showed equal results: to those of DSA for the detection of intracran ial aneurysms and may be used as a primary noninvasive screening test. In t he evaluation of aneurysms in neck and parent vessels, the concurrent use o f MR angiography and multiplanar reconstruction was far superior to the use of either MR angiography or DSA alone.