Non-contrast-enhanced magnetic resonance angiography: a reliable clinical tool for evaluating transplant renal artery stenosis

Aouad

Exploratory Research and Hypothesis in Medicine

et al. 2021

Background and objectives: Renal transplant patients often require periodic imaging to evaluate the transplant vessel anastomosis for potential vascular complications. The use of non-contrast enhanced magnetic resonance angiography (NCE-MRA) techniques is encouraged in these patients because they are at increased risk of nephrogenic systemic fibrosis (NSF) due to their renal insufficiency. This study aimed to evaluate the performance of two NCE-MRA techniques (three-dimensional [3D] balanced steady-state free precession [bSSFP] with inversion recovery and quiescent-interval slice-selective [QISS]) for the evaluation of renal allograft vasculature in patients with clinical suspicion, or Doppler ultrasound, or both of arterial anastomotic stenosis.Methods: A total of 43 patients were included in this retrospective study. Two radiologists independently scored the images from 3D bSSFP and QISS MRA sequences for image quality and confidence in anastomosis interpretation, and the degree of stenosis at the arterial anastomosis. Correlations with digital subtraction angiography (DSA) were carried out when available. In addition, inter-rater agreement was calculated.Results: In total, 43 patients underwent QISS and 3D bSSFP MRA. For QISS, all cases were adequate for evaluation. For 3D SSFP, 86% of cases were adequate for evaluation. There was a good-to-excellent inter-rater agreement for all scores and an excellent correlation between NCE-MRA and DSA results when available (12 patients).Conclusions: QISS and 3D SSFP showed good inter-rater agreement for image quality and stenosis grade, with more cases being of adequate image quality that used QISS. Further study is required; however, NCE-MRA shows

Section: Discussionmentioning

confidence: 71%

“…Previous studies have reported slightly higher numbers, which included 87% in a study of 15 patients, 16 and 95.4% of cases in a larger study of 369 examinations. 19 The differences in the reported success rate could be related to differences in the study design, technique implementation, or patient populations.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of Renal Allograft Vasculature Using Non-contrast 3D Inversion Recovery Balanced Steady-state Free Precession MRA and 2D Quiescent-interval Slice-selective MRA

Aouad

Exploratory Research and Hypothesis in Medicine

et al. 2021

“…The outcomes in detecting stenosis by MRA appear to be comparable with DSA and US [110]. Compared to DSA, NCE-MRA displays a sensitivity up to 100%, a specificity ranging from 85.7 to 90% and an accuracy of 91-96.6% [104,105,111,112]. Studies using CE-MRA report a comparable sensitivity and specificity [113][114][115][116][117].…”

Section: Long-term Vascular Complicationsmentioning

confidence: 98%

“…When the donor transplant artery is excessively long, artery kinking can occur, resulting in a turbulent blood flow. Several cases of artery kinking successfully depicted with MRA are described [104,105].…”

Section: Short-term Vascular Complicationsmentioning

confidence: 99%

MRI for diagnosis of post-renal transplant complications: current state-of-the-art and future perspectives

Schutter

Lantinga

Borra

et al. 2019

Magn Reson Mater Phy

Kidney transplantation has developed into a widespread procedure to treat end stage renal failure, with transplantation results improving over the years. Postoperative complications have decreased over the past decades, but are still an important cause of morbidity and mortality. Early accurate diagnosis and treatment is the key to prevent renal allograft impairment or even graft loss. Ideally, a diagnostic tool should be able to detect post-transplant renal dysfunction, differentiate between the different causes and monitor renal function during and after therapeutic interventions. Non-invasive imaging modalities for diagnostic purposes show promising results. Magnetic resonance imaging (MRI) techniques have a number of advantages, such as the lack of ionizing radiation and the possibility to obtain relevant tissue information without contrast, reducing the risk of contrast-induced nephrotoxicity. However, most techniques still lack the specificity to distinguish different types of parenchymal diseases. Despite some promising outcomes, MRI is still barely used in the post-transplantation diagnostic process. The aim of this review is to survey the current literature on the relevance and clinical applicability of diagnostic MRI modalities for the detection of various types of complications after kidney transplantation.

European Journal of Radiology Open

“…NCE-MRA including bSSFP techniques have shown to be reliable in depicting normal [27] and stenosed renal arteries [31][32][33], as well as of transplanted renal arteries [34]. Similarly, REACT may be a viable alternative to screen for and monitor patients with renal artery stenosis.…”

Section: Assessment Of Renal Artery Patencymentioning

confidence: 99%

REACT – A novel flow-independent non-gated non-contrast MR angiography technique using magnetization-prepared 3D non-balanced dual-echo dixon method: Preliminary clinical experience

Tan

Zhang

Tirukonda

et al. 2020

Flow-independent relaxation-based non-contrast MR angiography techniques yield good signal-to-noise ratio and high blood-tissue contrast, complementing non-contrast flow-dependent and contrast-enhanced MR angiography techniques in the assessment of vascular disorders. However, these techniques often suffer from imaging artifacts at high magnetic field strengths or across large fields-of-view. Relaxation-Enhanced Angiography without Contrast and Triggering (REACT) is a recently introduced flow-independent non-gated non-contrast three-dimensional MR angiography technique that has been developed to mitigate some of these issues. We present our initial experience with the clinical applications of REACT in imaging disorders of the central and peripheral vascular systems.