Comparison of whole body MR angiography at 1.5 and 3 Tesla in patients with hereditary hyperlipidemia

Abstract

Background Patients suffering from hereditary hyperlipidemia have a high risk for premature cardiovascular disease and death as a consequence of accelerated atherosclerosis. Purpose To prospectively and intra-individually compare image quality and detectability of stenoses in contrast enhanced whole-body MRA (WBMRA) at 1.5 and 3 Tesla (T) in patients with hereditary hyperlipidemia. Material and Methods Twenty-seven patients with hereditary hyperlipidemia received a 1.5 and 3 T gadopentetate dimeglumine contrast-enhanced WBMRA. Twenty-three defined arterial segments were analyzed regarding depiction of target vessels and image quality according to a 5-point-scale (‘not evaluable’ to ‘excellent’). Wilcoxon matched pair test was performed for comparison. Forty-three defined arterial segments were analyzed for the degree of stenosis (0%, 1–49%, 50–99% and 100%) as well as vessel alterations such as aneurysms. Chi-square test was performed for comparison. Results 1.5 T and 3 T scans yielded WBMRA with diagnostic quality in all patients. In seven of 23 arterial segments (30.4%) image quality was rated significantly higher at 3 T, whereas there was no significant difference in the remaining 16 segments between WBMRA at 1.5 T and 3 T. All relevant stenoses ( n = 5), occlusions ( n = 6), and aneurysms ( n = 3) were evaluated similarly at both field strengths. Conclusion WBMRA can be performed at 1.5 T and 3 T with diagnostic image quality. Image quality was significantly higher at 3 T than at 1.5 T in only 30.4% of the arterial segments. In order to effectively take advantage of the higher field strength, further optimization of sequence parameters and injection protocols for WBMRA at 3 T is necessary.