Blood flow quantification from 2D phase contrast MRI in renal arteries using an unsupervised data driven approach

Zöllner, Frank G.; Monssen, Jan Ankar; Rørvik, Jarle; Lundervold, Arvid; Schad, Lothar R.

doi:10.1016/j.zemedi.2008.10.011

Cited by 16 publications

(5 citation statements)

References 33 publications

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“…where Δ represents the phase difference. As signal phase is only unique between -and + , this corresponds to velocities being unique from -Venc to + Venc [8]. The obtained signal phase is carried over into the phase of the complex reconstructed images, and therefore, after reconstruction, two sets of images exist: the magnitude images and the velocity maps, which are the phase images.…”

Section: Pc-mri Acquisition Methodsmentioning

confidence: 99%

“…ROIs cannot be kept constant across time frames, and should rather be adjusted in each of them, to account for movement of the vessels during the cardiac cycle, unless spatial registration was performed beforehand. Alternatively, automatic ROI segmentation techniques requiring no adjustment, such as adaptive thresholding [28], graph searching [29], active contour [30,31], paraboloid velocity profiles [32] and k-mean clustering [8], show promise.…”

Section: Pc-mri Processingmentioning

confidence: 99%

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Phase-contrast magnetic resonance imaging to assess renal perfusion: a systematic review and statement paper

Villa

Ringgaard

Hermann

et al. 2019

Magn Reson Mater Phy

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Objective Phase-contrast magnetic resonance imaging (PC-MRI) is a non-invasive method used to compute blood flow velocity and volume. This systematic review aims to discuss the current status of renal PC-MRI and provide practical recommendations which could inform future clinical studies and its adoption in clinical practice. Methodology A comprehensive search of all the PC-MRI studies in human healthy subjects or patients related to the kidneys was performed. Results A total of 39 studies were included in which PC-MRI was used to measure renal blood flow (RBF) alongside other derivative hemodynamic parameters. PC-MRI generally showed good correlation with gold standard methods of RBF measurement, both in vitro and in vivo, and good reproducibility. Despite PC-MRI not being routinely used in clinical practice, there are several clinical studies showing its potential to support diagnosis and monitoring of renal diseases, in particular renovascular disease, chronic kidney disease and autosomal dominant polycystic kidney disease. Discussion Renal PC-MRI shows promise as a non-invasive technique to reliably measure RBF, both in healthy volunteers and in patients with renal disease. Future multicentric studies are needed to provide definitive normative ranges and to demonstrate the clinical potential of PC-MRI, likely as part of a multi-parametric renal MRI protocol.

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Section: Pc-mri Acquisition Methodsmentioning

confidence: 99%

Section: Pc-mri Processingmentioning

confidence: 99%

Phase-contrast magnetic resonance imaging to assess renal perfusion: a systematic review and statement paper

Villa

Ringgaard

Hermann

et al. 2019

Magn Reson Mater Phy

View full text Add to dashboard Cite

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“…Several methods have been proposed for (semi‐) automated 2D, (2D+t), 3D, or even (3D+t) segmentation of the arteries. A variety of image processing strategies have been applied: region growing (14), adaptive thresholding (15, 16), dynamic programming (17), and active contours (8, 18–20). Besides the methodological approaches, the ability of the methods to correctly account for the characteristics of the image and of the arteries is a key point to their successful clinical application.…”

Section: Discussionmentioning

confidence: 99%

Automated segmentation of the aorta from phase contrast MR images: Validation against expert tracing in healthy volunteers and in patients with a dilated aorta

Herment

Kachenoura

Lefort

et al. 2010

Magnetic Resonance Imaging

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Purpose: To assess if segmentation of the aorta can be accurately achieved using the modulus image of phase contrast (PC) magnetic resonance (MR) acquisitions.Materials and Methods: PC image sequences containing both the ascending and descending aorta of 52 subjects were acquired using three different MR scanners. An automated segmentation technique, based on a 2Dþt deformable surface that takes into account the features of PC aortic images, such as flow-related effects, was developed. The study was designed to: 1) assess the variability of our approach and its robustness to the type of MR scanner, and 2) determine its sensitivity to aortic dilation and its accuracy against an expert manual tracing.Results: Interobserver variability in the lumen area was 0.59 6 0.92% for the automated approach versus 10.09 6 8.29% for manual segmentation. The mean Dice overlap measure was 0.945 6 0.014. The method was robust to the aortic size and highly correlated (r ¼ 0.99) with the manual tracing in terms of aortic area and diameter.Conclusion: A fast and robust automated segmentation of the aortic lumen was developed and successfully tested on images provided by various MR scanners and acquired on healthy volunteers as well as on patients with a dilated aorta.

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“…A single 6 mm slice with a 256 x132 acquisition matrix reconstructed to voxel dimensions of 1.6 mm x 1.6 mm was acquired using a TR/TE of 10.7/6.5 ms and turbo field echo factor 50. Macrovascular arterial and venous vessels within the quadriceps muscles were identified using k means clustering (5 bins and unrestricted cluster size using velocity maps and magnitude images as input and an adaptive threshold of ten percent above average absolute water velocity of the quadriceps (19,30,79) .…”

Section: = • • * +mentioning

confidence: 99%

Exercise-induced fluid shifts are distinct to exercise mode and intensity: a comparison of blood flow-restricted and free-flow resistance exercise

Haddock

Hansen

Lindberg

et al. 2021

Journal of Applied Physiology

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Aim: MRI can provide fundamental tools in decoding physiological stressors stimulated by training paradigms. Acute physiological changes induced by three diverse exercise protocols known to elicit similar levels of muscle hypertrophy were evaluated using muscle functional magnetic resonance imaging (mfMRI). Methods: The study was a cross-over study with participants (n=10) performing three acute unilateral knee extensor exercise protocols to failure and a work matched control exercise protocol. Participants were scanned after each exercise protocol; 70% 1 repetition maximum (RM) (FF70); 20% 1RM (FF20); 20% 1RM with blood flow restriction (BFR20); free-flow (FF) control work matched to BFR20 (FF20WM). Post exercise mfMRI scans were used to obtain interleaved measures of muscle R2 (indicator of edema), R2' (indicator of deoxyhemoglobin), muscle cross sectional area (CSA) blood flow and diffusion. Results: Both BFR20 and FF20 exercise resulted in a larger acute decrease in R2, decrease in R2', and expansion of the extracellular compartment with slower rates of recovery. BFR20 caused greater acute increases in muscle CSA than FF20WM and FF70. Only BFR20 caused acute increases in intracellular volume. Post-exercise muscle blood flow was higher after FF70 and FF20 exercise than BFR20. Acute changes in mean diffusivity were similar across all exercise protocols. Conclusion: This study was able to differentiate the acute physiological responses between anabolic exercise protocols. Low-load exercise protocols, known to have relatively higher energy contributions from glycolysis at task failure, elicited a higher mfMRI response. Noninvasive mfMRI represents a promising tool for decoding mechanisms of anabolic adaptation in muscle.

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Blood flow quantification from 2D phase contrast MRI in renal arteries using an unsupervised data driven approach

Cited by 16 publications

References 33 publications

Phase-contrast magnetic resonance imaging to assess renal perfusion: a systematic review and statement paper

Phase-contrast magnetic resonance imaging to assess renal perfusion: a systematic review and statement paper

Automated segmentation of the aorta from phase contrast MR images: Validation against expert tracing in healthy volunteers and in patients with a dilated aorta

Exercise-induced fluid shifts are distinct to exercise mode and intensity: a comparison of blood flow-restricted and free-flow resistance exercise

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