Diagnostic value of fast breath-hold MRI techniques in aortic dissection

Objective: To evaluate the value of both fast breath-hold MRI techniques, i.e. true FISP and 3D CE MRA, in diagnosing aortic dissection (AD) and associated lesions. Methods: One hundred and thirteen consecutive patients with clinically suspected or known AD were prospectively examined with both true FISP and 3D CEMRA. All MR images were evaluated independently by two radiologists, and the results were compared with the findings of surgery and other imaging modalities (including DSA, TEE, CT, and conventional MRI). Results: Among those 113 patients studied by true FISP and 3D CE MRA, the results were as follows: 74 patients with AD, 15 with thoracic aortic aneurysms, 5 with aortic atherosclerosis with mural thrombus, and 19 with normal aorta. Compared to the results of surgery and other imaging studies, the sensitivity and specificity in the diagnosis of AD with true FISP and 3D CE MRA were 98.6% and 100.0%, and 100.0% and 100.0%, respectively. In 74 patients with AD, 56 were with intimal entry, one with intimal intussusception, 9 with thrombus-obliterated AD with ulcer-like lesions, and 8 with aortic intramural hematoma. Among 59 intimal entries of 56 patients, true FISP demonstrated 37 (62.7%) and 3D CE MRA demonstrated 54 (91.5%). The demonstration rate of the intimal entry of 3D CE MRA was obviously higher than that of true FISP (χ2=13.88, P<0.01). In 345 major branch vessels of 74 AD patients, the identical rate of the two MR techniques was 84.3%(291/345). The rate of positive demonstration was 29.3% in 3D CEMRA and 22.0% in true FISP, respectively. Conclusion: Both fast breath-hold MR imaging techniques (true FISP and 3D CE MRA) are accurate and reliable in the diagnosis of AD, and these two MR techniques are superior to conventional MRI, particularly in evaluating intimal entry and branch vessel involvement