S-Space College of Medicine/School of Medicine (의과대학/대학원) Dept. of Medicine (의학과) Theses (Master's Degree_의학과)
단일 용량 조영제를 사용한 3 T 자기공명 지연 조영 영상 -고식적 이중용량 1.5 T 자기공명 지연 조영 영상과의 비교-
Single Dose Gadolinium Contrast for 3 T Late Gadolinium Enhancement MRI -Intra-individual Comparison with Conventional Double Dose at 1.5 T MRI-
- 의과대학 의학과
- Issue Date
- 서울대학교 대학원
- Myocardial infarction; magnetic resonance imaging; 3 Tesla; contrast agent; gadolinium; image quality; infarct size
- 학위논문 (석사)-- 서울대학교 대학원 : 의학과, 2015. 2. 이활.
- Purpose: 3 T late gadolinium enhancement (LGE) imaging is expected to provide comparable image quality to 1.5 T even with reduction of gadolinium contrast, thanks to superior signal to noise ratio and longer T1 relaxation time of normal myocardium. This prospective study was designed to perform intra-individual comparison of 3 T MR with use of 0.1 mmol/kg of gadoterate meglumine to 1.5 T MR with use of 0.2 mmol/kg of the same gadolinium contrast for the assessment of myocardial infarction.
Materials and Methods: In this prospective study, a total of ten patients (M:F = 8:2
mean age, 62.5 ± 11.8 years) diagnosed as old myocardial infarction were examined at 3 T MR with single dose within two weeks after 1.5 T conventional double dose MR. A single representative short-axis image was acquired at three-time point temporal scans (10 minute, 15 minute and 20 minute) after administration of gadolinium agent (Uniray, gadoterate meglumine, Dongkook Pharmaceutical Co., Ltd). Two contrast to noise ratios (CNRs) between infarcted and normal myocardium and between infarcted and left ventricular (LV) cavity were calculated and compared intra-individually at each temporal scan. Two independent readers assessed infarct size semiautomatically by using a threshold of 6 standard deviations above the mean signal intensity of the remote myocardium. The interobserver reproducibility was also evaluated using intraclass correlation coefficient (ICC).
Results: Despite the usage of single dose of gadolinium, the mean values of infarcted myocardium tended to be higher at 3 T MR than 1.5 T MR with double dose at each time scan. 3 T LGE images with the single dose of gadolinium showed no significant difference in CNR between infarcted and normal myocardium at each time scan (all, p > 0.05). The CNR between infarcted myocardium and LV cavity was significantly better at 10 minute scan, compared to that of 1.5 T double dose (12.4 ± 8.2 vs. 7.6 ± 4.5, p = 0.049) but there were no differences at 15 and 20 minute scan. The measurement of relative infarct size was not significantly different between 1.5 T and 3 T MR by both observers 1 and 2 (all, p > 0.05). Interobserver reproducibility was excellent at 3 T single-dose MR (ICC range: 0.962-0.968) and good or excellent at 1.5 T double-dose MR (ICC range: 0.769-0.866).
Conclusions: LGE imaging at 3 T with single-dose contrast is as effective as 1.5 T conventional double-dose MR for the delineation of infarcted myocardium from non-infarcted myocardium and is superior for detection of infarcted myocardium from blood cavity at 10 minute scan. Therefore, 3 T LGE imaging using a single dose of gadolinium is expected to not only reduce risk of nephrogenic systemic fibrosis but also help to delineate subendocardial infarction