Browsing by Author "Hajhosseiny, Reza"
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- ItemAutomated detection of cardiac rest period for trigger delay calculation for image-based navigator coronary magnetic resonance angiography(NLM (Medline), 2023) Wood, Gregory; Uglebjerg Pedersen, Alexandra; Kunze, Karl P; Neji, Radhouene; Hajhosseiny, Reza; Wetzl, Jens; Yoon, Seung Su; Schmidt, Michaela; Norgaard, Bjarne Linde; Prieto Vásquez, Claudia; Botnar, René Michael; Kim, Won YongBACKGROUND: Coronary magnetic resonance angiography (coronary MRA) is increasingly being considered as a clinically viable method to investigate coronary artery disease (CAD). Accurate determination of the trigger delay to place the acquisition window within the quiescent part of the cardiac cycle is critical for coronary MRA in order to reduce cardiac motion. This is currently reliant on operator-led decision making, which can negatively affect consistency of scan acquisition. Recently developed deep learning (DL) derived software may overcome these issues by automation of cardiac rest period detection. METHODS: Thirty individuals (female, n = 10) were investigated using a 0.9 mm isotropic image-navigator (iNAV)-based motion-corrected coronary MRA sequence. Each individual was scanned three times utilising different strategies for determination of the optimal trigger delay: (1) the DL software, (2) an experienced operator decision, and (3) a previously utilised formula for determining the trigger delay. Methodologies were compared using custom-made analysis software to assess visible coronary vessel length and coronary vessel sharpness for the entire vessel length and the first 4 cm of each vessel. RESULTS: There was no difference in image quality between any of the methodologies for determination of the optimal trigger delay, as assessed by visible coronary vessel length, coronary vessel sharpness for each entire vessel and vessel sharpness for the first 4 cm of the left mainstem, left anterior descending or right coronary arteries. However, vessel length of the left circumflex was slightly greater using the formula method. The time taken to calculate the trigger delay was significantly lower for the DL-method as compared to the operator-led approach (106 ± 38.0 s vs 168 ± 39.2 s, p < 0.01, 95% CI of difference 25.5-98.1 s). CONCLUSIONS: Deep learning-derived automated software can effectively and efficiently determine the optimal trigger delay for acquisition of coronary MRA and thus may simplify workflow and improve reproducibility.
- ItemCoronary Magnetic Resonance Angiography in Chronic Coronary Syndromes(FRONTIERS MEDIA SA, 2021) Hajhosseiny, Reza; Munoz, Camila; Cruz, Gastao; Khamis, Ramzi; Kim, Won Yong; Prieto, Claudia; Botnar, Rene M.Cardiovascular disease is the leading cause of mortality worldwide, with atherosclerotic coronary artery disease (CAD) accounting for the majority of cases. X-ray coronary angiography and computed tomography coronary angiography (CCTA) are the imaging modalities of choice for the assessment of CAD. However, the use of ionising radiation and iodinated contrast agents remain drawbacks. There is therefore a clinical need for an alternative modality for the early identification and longitudinal monitoring of CAD without these associated drawbacks. Coronary magnetic resonance angiography (CMRA) could be a potential alternative for the detection and monitoring of coronary arterial stenosis, without exposing patients to ionising radiation or iodinated contrast agents. Further advantages include its versatility, excellent soft tissue characterisation and suitability for repeat imaging. Despite the early promise of CMRA, widespread clinical utilisation remains limited due to long and unpredictable scan times, onerous scan planning, lower spatial resolution, as well as motion related image quality degradation. The past decade has brought about a resurgence in CMRA technology, with significant leaps in image acceleration, respiratory and cardiac motion estimation and advanced motion corrected or motion-resolved image reconstruction. With the advent of artificial intelligence, great advances are also seen in deep learning-based motion estimation, undersampled and super-resolution reconstruction promising further improvements of CMRA. This has enabled high spatial resolution (1 mm isotropic), 3D whole heart CMRA in a clinically feasible and reliable acquisition time of under 10 min. Furthermore, latest super-resolution image reconstruction approaches which are currently under evaluation promise acquisitions as short as 1 min. In this review, we will explore the recent technological advances that are designed to bring CMRA closer to clinical reality.
- ItemEnd-to-end deep learning nonrigid motion-corrected reconstruction for highly accelerated free-breathing coronary MRA(2021) Qi, Haikun; Hajhosseiny, Reza; Cruz, Gastao; Kuestner, Thomas; Kunze, Karl; Neji, Radhouene; Botnar, René Michael; Prieto Vásquez, ClaudiaPurpose: To develop an end-to-end deep learning technique for nonrigid motion-corrected (MoCo) reconstruction of ninefold undersampled free-breathing whole-heart coronary MRA (CMRA).
- ItemFully self-gated free-running 3D Cartesian cardiac CINE with isotropic whole-heart coverage in less than 2 min(2021) Küstner, Thomas; Bustin, Aurelien; Jaubert, Olivier; Hajhosseiny, Reza; Masci, Pier Giorgio; Neji, Radhouene; Botnar, René Michael; Prieto Vásquez, Claudia
- ItemHigh-resolution non-contrast free-breathing coronary cardiovascular magnetic resonance angiography for detection of coronary artery disease : validation against invasive coronary angiography(2022) Nazir, Muhummad S.; Bustin, Aurélien; Hajhosseiny, Reza; Yazdani, Momina; Ryan, Matthew; Vergani, Vittoria; Neji, Radhouene; Kunze, Karl P.; Perera, Divaka; Botnar, René Michael; Prieto Vásquez, ClaudiaCoronary artery disease (CAD) is the single most common cause of death worldwide. Recent technological developments with coronary cardiovascular magnetic resonance angiography (CCMRA) allow high-resolution free-breathing imaging of the coronary arteries at submillimeter resolution without contrast in a predictable scan time of ~ 10 min. The objective of this study was to determine the diagnostic accuracy of high-resolution CCMRA for CAD detection against the gold standard of invasive coronary angiography (ICA). Methods: Forty-five patients (15 female, 62 ± 10 years) with suspected CAD underwent sub-millimeter-resolution (0.6 mm3) non-contrast CCMRA at 1.5T in this prospective clinical study from 2019–2020. Prior to CCMR, patients were given an intravenous beta blockers to optimize heart rate control and sublingual glyceryl trinitrate to promote coronary vasodilation. Obstructive CAD was defined by lesions with ≥ 50% stenosis by quantitative coronary angiography on ICA. Results: The mean duration of image acquisition was 10.4 ± 2.1 min. On a per patient analysis, the sensitivity, specificity, positive predictive value and negative predictive value (95% confidence intervals) were 95% (75–100), 54% (36–71), 60% (42–75) and 93% (70–100), respectively. On a per vessel analysis the sensitivity, specificity, positive predictive value and negative predictive value (95% confidence intervals) were 80% (63–91), 83% (77–88), 49% (36–63) and 95% (90–98), respectively. Conclusion: As an important step towards clinical translation, we demonstrated a good diagnostic accuracy for CAD detection using high-resolution CCMRA, with high sensitivity and negative predictive value. The positive predictive value is moderate, and combination with CMR stress perfusion may improve the diagnostic accuracy. Future multicenter evaluation is now required
- ItemHigh-Spatial-Resolution 3D Whole-Heart MRI T2 Mapping for Assessment of Myocarditis(2021) Bustin, Aurélien; Hua, Alina; Milotta, Giorgia; Jaubert, Olivier; Hajhosseiny, Reza; Ismail, Tevfik F.; Botnar, René Michael; Prieto Vásquez, ClaudiaBackground: Clinical guidelines recommend the use of established T2 mapping sequences to detect and quantify myocarditis and edema, but T2 mapping is performed in two dimensions with limited coverage and repetitive breath holds.Purpose:To assess the reproducibility of an accelerated free-breathing three-dimensional (3D) whole-heart T2 MRI mapping se-quence in phantoms and participants without a history of cardiac disease and to investigate its clinical performance in participants with suspected myocarditis.Materials and Methods: Eight participants (three women, mean age, 31 years 6 4 [standard deviation]; cohort 1) without a history of cardiac disease and 25 participants (nine women, mean age, 45 years 6 17; cohort 2) with clinically suspected myocarditis underwent accelerated free-breathing 3D whole-heart T2 mapping with 100% respiratory scanning efficiency at 1.5 T. The participants were enrolled from November 2018 to August 2020. Three repeated scans were performed on 2 separate days in cohort 1. Segmental variations in T2 relaxation times of the left ventricular myocardium were assessed, and intrasession and intersession reproducibility were measured. In cohort 2, segmental myocardial T2 values, detection of focal inflammation, and map quality were compared with those obtained from clinical breath-hold two-dimensional (2D) T2 mapping. Statistical differences were assessed using the nonparametric Mann-Whitney and Kruskal-Wallis tests, whereas the paired Wilcoxon signed-rank test was used to assess subjective scores.Results: Whole-heart T2 maps were acquired in a mean time of 6 minutes 53 seconds 6 1 minute 5 seconds at 1.5 mm3 resolution. Breath-hold 2D and free-breathing 3D T2 mapping had similar intrasession (mean T2 change of 3.2% and 2.3% for 2D and 3D, respectively) and intersession (4.8% and 4.9%, respectively) reproducibility. The two T2 mapping sequences showed similar map quality (P = .23, cohort 2). Abnormal myocardial segments were identified with confidence (score 3) in 14 of 25 participants (56%) with 3D T2 mapping and only in 10 of 25 participants (40%) with 2D T2 mapping.Conclusion: High-spatial-resolution three-dimensional (3D) whole-heart T2 mapping shows high intrasession and intersession repro-ducibility and helps provide T2 myocardial characterization in agreement with clinical two-dimensional reference, while enabling 3D assessment of focal disease with higher confidence.
- ItemImaging the extracellular matrix in prevalent cardiovascular diseases(MDPI AG, 2020) Chaher, Nadia; Hajhosseiny, Reza; Phinikaridou, Alkystis; Botnar, René MichaelThe extracellular matrix (ECM) is a highly complex macromolecular network present in all tissues and organs. The ECM is continuously remodelling under an orchestrated process facilitated by many matrix-degrading and matrix-synthesising enzymes in both health and disease. Disturbance of this balance can be the result of or can lead to various diseases. In cardiovascular diseases (CVDs), changes to the ECM are evident in conditions including: atherosclerosis, myocardial infarction (MI), venous thromboembolism (VTE) and abdominal aortic aneurysm (AAA). ECM proteins and ECM regulating enzymes are differently expressed in various CVDs. Most importantly, the altered deposition, macromolecule arrangement and activity of the ECM makes it an attractive marker of disease onset, pathogenesis and progression. Many medical imaging modalities allow disease assessment by exploiting native image contrast, by using non-targeted or by using protein or cell specific (targeted) imaging probes. However, the ability to directly visualise and quantify changes in specific ECM proteins enhances our understanding of the biological role of these proteins, enables monitoring of disease progression and response to treatment and may improve patient diagnosis and allocation of personalised therapies. This review focuses on the biochemistry of the major extracellular matrix proteins and advancements in the development of ECM-targeted probes for molecular imaging of CVD, particularly for applications of molecular magnetic resonance imaging (MRI) and position emission tomography (PET) imaging.
- ItemSimultaneous Highly Efficient Contrast-Free Lumen and Vessel Wall MR Imaging for Anatomical Assessment of Aortic Disease(2023) Muñoz, Camila; Fotaki, Anastasia; Hua, Alina; Hajhosseiny, Reza; Kunze, Karl P.; Ismail, Tevfik F.; Neji, Radhouene; Pushparajah, Kuberan; Botnar, René Michael; Prieto Vásquez, ClaudiaBackground: Bright-blood lumen and black-blood vessel wall imaging are required for the comprehensive assessment of aortic disease. These images are usually acquired separately, resulting in long examinations and potential misregistration between images. Purpose: To characterize the performance of an accelerated and respiratory motion-compensated three-dimensional (3D) cardiac MRI technique for simultaneous contrast-free aortic lumen and vessel wall imaging with an interleaved T2 and inversion recovery prepared sequence (iT2Prep-BOOST). Study Type: Prospective. Population: A total of 30 consecutive patients with aortopathy referred for a clinically indicated cardiac MRI examination (9 females, mean age ± standard deviation: 32 ± 12 years). Field Strength/Sequence: 1.5-T; bright-blood MR angiography (diaphragmatic navigator-gated T2-prepared 3D balanced steady-state free precession [bSSFP], T2Prep-bSSFP), breath-held black-blood two-dimensional (2D) half acquisition single-shot turbo spin echo (HASTE), and 3D bSSFP iT2Prep-BOOST. Assessment: iT2Prep-BOOST bright-blood images were compared to T2prep-bSSFP images in terms of aortic vessel dimensions, lumen-to-myocardium contrast ratio (CR), and image quality (diagnostic confidence, vessel sharpness and presence of artifacts, assessed by three cardiologists on a 4-point scale, 1: nondiagnostic to 4: excellent). The iT2Prep-BOOST black-blood images were compared to 2D HASTE images for quantification of wall thickness. A visual comparison between computed tomography (CT) and iT2Prep-BOOST was performed in a patient with chronic aortic dissection. Statistical Tests: Paired t-tests, Wilcoxon signed-rank tests, intraclass correlation coefficient (ICC), Bland–Altman analysis. A P value < 0.05 was considered statistically significant. Results: Bright-blood iT2Prep-BOOST resulted in significantly improved image quality (mean ± standard deviation 3.8 ± 0.5 vs. 3.3 ± 0.8) and CR (2.9 ± 0.8 vs. 1.8 ± 0.5) compared with T2Prep-bSSFP, with a shorter scan time (7.8 ± 1.7 minutes vs. 12.9 ± 3.4 minutes) while providing a complementary 3D black-blood image. Aortic lumen diameter and vessel wall thickness measurements in bright-blood and black-blood images were in good agreement with T2Prep-bSSFP and HASTE images (<0.02 cm and <0.005 cm bias, respectively) and good intrareader (ICC > 0.96) and interreader (ICC > 0.94) agreement was observed for all measurements. Data Conclusion: iT2Prep-BOOST might enable time-efficient simultaneous bright- and black-blood aortic imaging, with improved image quality compared to T2Prep-bSSFP and HASTE imaging, and comparable measurements for aortic wall and lumen dimensions. Evidence Level: 2. Technical Efficacy: Stage 2.
- ItemWhole-heart non-rigid motion corrected coronary MRA with autofocus virtual 3D iNAV(ELSEVIER SCIENCE INC, 2022) Schneider, Alina; Cruz, Gastao; Munoz, Camila; Hajhosseiny, Reza; Kuestner, Thomas; Kunze, Karl P.; Neji, Radhouene; Botnar, Rene M.; Prieto, ClaudiaPurpose: Respiratory motion-corrected coronary MR angiography (CMRA) has shown promise for assessing coronary disease. By incorporating coronal 2D image navigators (iNAVs), respiratory motion can be corrected for in a beat-to-beat basis using translational correction in the foot-head (FH) and right-left (RL) directions and in a bin-to-bin basis using non-rigid motion correction addressing the remaining FH, RL and anterior-posterior (AP) motion. However, with this approach beat-to-beat AP motion is not corrected for. In this work we investigate the effect of remaining beat-to-beat AP motion and propose a virtual 3D iNAV that exploits autofocus motion correction to enable beat-to-beat AP and improved RL intra-bin motion correction. Methods: Free-breathing 3D whole-heart CMRA was acquired using a 3-fold undersampled variable-density Cartesian trajectory. Beat-to-beat 3D translational respiratory motion was estimated from the 2D iNAVs in FH and RL directions, and in AP direction with autofocus assuming a linear relationship between FH and AP movement of the heart. Furthermore, motion in RL was also refined using autofocus. This virtual 3D (v3D) iNAV was incorporated in a non-rigid motion correction (NRMC) framework. The proposed approach was tested in 12 cardiac patients, and visible vessel length and vessel sharpness for the right (RCA) and left (LAD) coronary arteries were compared against 2D iNAV-based NRMC. Results: Average vessel sharpness and length in v3D iNAV NRMC was improved compared to 2D iNAV NRMC (vessel sharpness: RCA: 56 +/- 1% vs 52 +/- 11%, LAD: 49 +/- 8% vs 49 +/- 7%; visible vessel length: RCA: 5.98 +/- 1.37 cm vs 5.81 +/- 1.62 cm, LAD: 5.95 +/- 1.85 cm vs 4.83 +/- 1.56 cm), however these improvements were not statistically significant. Conclusion: The proposed virtual 3D iNAV NRMC reconstruction further improved NRMC CMRA image quality by reducing artefacts arising from residual AP motion, however the level of improvement was subject-dependent.