Noncontrast dynamic MRA in intracranial arteriovenous malformation (AVM): comparison with time of flight (TOF) and digital subtraction angiography (DSA)

Abstract

Purpose Digital subtraction angiography (DSA) remains the gold standard to diagnose intracranial arteriovenous malformations (AVMs) but is invasive. Existing magnetic resonance angiography (MRA) is suboptimal for assessing the hemodynamics of AVMs. The objective of this study was to evaluate the clinical utility of a novel noncontrast four-dimensional (4D) dynamic MRA (dMRA) in the evaluation of intracranial AVMs through comparison with DSA and time-of-flight (TOF) MRA. Materials and methods Nineteen patients (12 women, mean age 26.2±10.7 years) with intracranial AVMs were examined with 4D dMRA, TOF and DSA. Spetzler–Martin grading scale was evaluated using each of the above three methods independently by two raters. Diagnostic confidence scores for three components of AVMs (feeding artery, nidus and draining vein) were also rated. Kendall's coefficient of concordance was calculated to evaluate the reliability between two raters within each modality (dMRA, TOF, TOF plus dMRA). The Wilcoxon signed-rank test was applied to compare the diagnostic confidence scores between each pair of the three modalities Results dMRA was able to detect 16 out of 19 AVMs, and the ratings of AVM size and location matched those of DSA. The diagnostic confidence scores by dMRA were adequate for nidus (3.5/5), moderate for feeding arteries (2.5/5) and poor for draining veins (1.5/5). The hemodynamic information provided by dMRA improved diagnostic confidence scores by TOF MRA. Conclusion As a completely noninvasive method, 4D dMRA offers hemodynamic information with a temporal resolution of 50–100 ms for the evaluation of AVMs and can complement existing methods such as DSA and TOF MRA.

4D DSA a new technique for arteriovenous malformation evaluation: a feasibility study

“…Each reviewer was asked to complete an evaluation form assessing each of the abovementioned characteristics in a commonly used four-point grading scale. [5][6][7] Once the images were scored for each modality, the reviewers were asked to state if any one modality was acceptable as a single imaging modality that provided all necessary information to evaluate the AVM and plan a treatment strategy. Thus, in total, the four reviewers evaluated six cases yielding 24 independent evaluations for 2D, 3D, and 4D DSA.…”

Application of Time-Resolved 3D Digital Subtraction Angiography to Plan Cerebral Arteriovenous Malformation Radiosurgery

“…25 Despite that the advancements in MR imaging technique such as 4D-MRA have enabled temporal information to be recorded, its limitations are still prominent. 26,27 Additionally, differences in AVM nidus contouring-derived MR images increase the likelihood of mismatch between the dose contour and the exact nidus volume during treatment planning. Stereotactic 4D-DSA may facilitate the treatment planning by providing the hemodynamics and morphology of AVM/DAVF in 1 stop.…”

Fast Contrast-Enhanced 4D MRA and 4D Flow MRI Using Constrained Reconstruction (HYPRFlow): Potential Applications for Brain Arteriovenous Malformations

“…3,4,7–9,26 Noncontrast 4D arterial spin-labeling methods provide excellent temporal resolution and arterial imaging; venous imaging with these methods can be limited due to transit-time signal decay. 27–29 Radial encoding without constrained reconstruction has been successfully used to accelerate acquisition and imaging of AVMs but has SNR limitations. 30 The advantage of combining radial encoding and constrained reconstructions to increase SNR has been previously demonstrated in healthy subjects 31 and patients with AVMs.…”