Browsing by Author "Hua, Alina"

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    Efficient non-contrast enhanced 3D Cartesian cardiovascular magnetic resonance angiography of the thoracic aorta in 3 min
    (2022) Fotaki, Anastasia; Munoz, Camila; Emanuel, Yaso; Hua, Alina; Bosio, Filippo; Kunze, Karl P.; Neji, Radhouene; Masci, Pier Giorgio; Botnar, Rene M.; Prieto, Claudia
    Background: The application of cardiovascular magnetic resonance angiography (CMRA) for the assessment of thoracic aortic disease is often associated with prolonged and unpredictable acquisition times and residual motion artefacts. To overcome these limitations, we have integrated undersampled acquisition with image-based navigators and inline non-rigid motion correction to enable a free-breathing, contrast-free Cartesian CMRA framework for the visualization of the thoracic aorta in a short and predictable scan of 3 min.
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    Evaluation of myocarditis with a free-breathing three-dimensional isotropic whole-heart joint T1 and T2 mapping sequence
    (ELSEVIER SCIENCE INC, 2024) Hua, Alina; Velasco, Carlos; Munoz, Camila; Milotta, Giorgia; Fotaki, Anastasia; Bosio, Filippo; Granlund, Inka; Sularz, Agata; Chiribiri, Amedeo; Kunze, Karl P.; Botnar Rene, Michael; Prieto Vásquez, Claudia Del Carmen; Ismail, Tevfik F.
    Background: The diagnosis of myocarditis by cardiovascular magnetic resonance (CMR) requires the use of T2 and T1 weighted imaging, ideally incorporating parametric mapping. Current two-dimensional (2D) mapping sequences are acquired sequentially and involve multiple breath-holds resulting in prolonged scan times and anisotropic image resolution. We developed an isotropic free-breathing three-dimensional (3D) whole-heart sequence that allows simultaneous T1 and T2 mapping and validated it in patients with suspected myocarditis. Methods: Eighteen healthy volunteers and 28 patients with suspected myocarditis underwent conventional 2D T1 and T2 mapping with whole-heart coverage and 3D joint T1/T2 mapping on a 1.5T scanner. Acquisition time, image quality, and diagnostic performance were compared. Qualitative analysis was performed using a 4-point Likert scale. Bland-Altman plots were used to assess the quantitative agreement between 2D and 3D sequences. Results: The 3D T1/T2 sequence was acquired in 8 min 26 s under free breathing, whereas 2D T1 and T2 sequences were acquired with breath-holds in 11 min 44 s (p = 0.0001). All 2D images were diagnostic. For 3D images, 89% (25/ 28) of T1 and 96% (27/28) of T2 images were diagnostic with no significant difference in the proportion of diagnostic images for the 3D and 2D T1 (p = 0.2482) and T2 maps (p = 1.0000). Systematic bias in T1 was noted with biases of 102, 115, and 152 ms for basal-apical segments, with a larger bias for higher T1 values. Good agreement between T2 values for 3D and 2D techniques was found (bias of 1.8, 3.9, and 3.6 ms for basal-apical segments). The sensitivity and specificity of the 3D sequence for diagnosing acute myocarditis were 74% (95% confidence interval [CI] 49%-91%) and 83% (36%-100%), respectively, with a c-statistic (95% CI) of 0.85 (0.79-0.91) and no statistically significant difference between the 2D and 3D sequences for the detection of acute myocarditis for T1 (p = 0.2207) or T2 (p = 1.0000). Conclusion: Free-breathing whole-heart 3D joint T1/T2 mapping was comparable to 2D mapping sequences with respect to diagnostic performance, but with the added advantages of free breathing and shorter scan times. Further work is required to address the bias noted at high T1 values, but this did not significantly impact diagnostic accuracy.
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    High-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, Claudia
    Background: 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.
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    Non-rigid motion-compensated 3D whole-heart T2 mapping in a hybrid 3T PET-MR system
    (2024) Schneider, Alina; Munoz, Camila; Hua, Alina; Ellis, Sam; Jeljeli, Sami; Kunze, Karl P.; Neji, Radhouene; Reader, Andrew J.; Reyes, Eliana; Ismail, Tevfik F.; Botnar, Rene M.; Prieto, Claudia
    Purpose: Simultaneous PET-MRI improves inflammatory cardiac disease diagnosis. However, challenges persist in respiratory motion and mis-registration between free-breathing 3D PET and 2D breath-held MR images. We propose a free-breathing non-rigid motion-compensated 3D T-2-mapping sequence enabling whole-heart myocardial tissue characterization in a hybrid 3T PET-MR system and provides non-rigid respiratory motion fields to correct also simultaneously acquired PET data.Methods: Free-breathing 3D whole-heart T-2-mapping was implemented on a hybrid 3T PET-MRI system. Three datasets were acquired with different T-2-preparation modules (0, 28, 55 ms) using 3-fold under sampled variable-density Cartesian trajectory. Respiratory motion was estimated via virtual 3D image navigators, enabling multi-contrast non-rigid motion-corrected MR reconstruction. T-2-maps were computed using dictionary-matching. Approach was tested in phantom, 8 healthy subjects, 14 MR only and 2 PET-MR patients with suspected cardiac disease and compared with spin echo reference (phantom) and clinical 2D T-2-mapping (in-vivo).Results: Phantom results show a high correlation (R-2 = 0.996) between proposed approach and gold standard 2D T-2 mapping. In-vivo 3D T-2-mapping average values in healthy subjects (39.0 +/- 1.4 ms) and patients (healthy tissue) (39.1 +/- 1.4 ms) agree with conventional 2D T-2-mapping (healthy = 38.6 +/- 1.2 ms, patients = 40.3 +/- 1.7 ms). Bland-Altman analysis reveals bias of 1.8 ms and 95% limits of agreement (LOA) of -2.4-6 ms for healthy subjects, and bias of 1.3 ms and 95% LOA of -1.9 to 4.6 ms for patients.Conclusion: Validated efficient 3D whole-heart T-2-mapping at hybrid 3T PET-MRI provides myocardial inflammation characterization and non-rigid respiratory motion fields for simultaneous PET data correction. Comparable T-2 values were achieved with both 3D and 2D methods. Improved image quality was observed in the PET images after MR-based motion correction.
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    Simultaneous 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, Claudia
    Background: 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.
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    Simultaneous T-1, T-2, and T-1 rho cardiac magnetic resonance fingerprinting for contrast agent-free myocardial tissue characterization
    (WILEY, 2021) Velasco, Carlos; Cruz, Gastao; Lavin, Begona; Hua, Alina; Fotaki, Anastasia; Botnar, Rene M.; Prieto, Claudia
    Purpose: To develop a simultaneous T-1, T-2, and T-1 rho cardiac magnetic resonance fingerprinting (MRF) approach to enable comprehensive contrast agent-free myocardial tissue characterization in a single breath-hold scan.