Abstract No. 698 ■ FEATURED ABSTRACT Role of Time-resolved angiography With Interleaved Stochastic Trajectories (TWIST) magnetic resonance angiography for treatment planning in Nonspecific aorto-arteritis: a prospective study

Abstract

Nonspecific aorto-arteritis (NSAA) is a rare, chronic granulomatous panarteritis affecting primarily aorta and its branches. DSA is gold standard for the assessment of vascular involvement in these patients. Recent advances in MR Angiography such as Time-resolved angiography With Interleaved Stochastic Trajectories (TWIST) sequence can noninvasively assess the vascular involvement. We conducted a prospective study to evaluate the role of TWIST MR angiography for treatment planning in NSAA patients. Over the period between 2017 and 2019, 17 patients with NSAA were included in the study. Contrast-enhanced MRA using TWIST and diagnostic digital subtraction angiography (DSA) was performed in all the 17 patients. The average age of our patient cohort was 27.13 years and majority were females (11 were females and 6 patients were males). 17 patients underwent both MRA using TWIST sequence and DSA. Data from both MRA and DSA findings were compared, considering DSA is gold standard for the evaluation of arterial system. Common vessel involved are right renal artery (82.35%) followed by abdominal aorta (70.6%) followed by left renal artery (64.7%). Left subclavian artery was involved in 10 (58.8%) patients and right subclavian artery in 6 (35.3%) patients. In all the patients, the involved vessels were correctly identified in both TWIST angiography images and DSA. The sensitivity and specificity of TWIST MRA is 100% as compared to DSA in the detection of lesions involving Aorta, arch, arch vessels, celiac artery, SMA. However, the sensitivity and specificity of TWIST MR angiography in the assessment of renal arteries are 100% and 71.4% respectively. However, the sensitivity and specificity of VA lesion evaluation in 85.7% and 33.3%, respectively. TWIST MRA can be effective for the evaluation of vascular involvement in treatment planning in NSAA patients. TWIST MRA will be useful in those patients where breath holding is an issue or in uncooperative patients. It provides dynamic assessment of vascular system noninvasively. To the best of our knowledge, there is no study in the literature, which used TWIST MRA in the vascular evaluation in the patients of NSAA.