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Miao Q, Hua S, Gong Y, Lyu Z, Qian P, Liu C, Jin W, Hu P, Qi H. Free-Breathing Non-Contrast T1ρ Dispersion MRI of Myocardial Interstitial Fibrosis in Comparison with Extracellular Volume Fraction. J Cardiovasc Magn Reson 2024:101093. [PMID: 39245148 DOI: 10.1016/j.jocmr.2024.101093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Revised: 08/27/2024] [Accepted: 09/03/2024] [Indexed: 09/10/2024] Open
Abstract
BACKGROUND Myocardial fibrosis is a common feature in various cardiac diseases. It causes adverse cardiac remodeling and is associated with poor clinical outcomes. Late gadolinium enhancement (LGE) and extracellular volume fraction (ECV) are the standard MRI techniques for detecting focal and diffuse myocardial fibrosis. However, these contrast-enhanced techniques require the administration of gadolinium contrast agents, which is not applicable to patients with gadolinium contraindications. To eliminate the need of contrast agents, we develop and apply an endogenous free-breathing T1ρ dispersion imaging technique (FB-MultiMap) for diagnosing diffuse myocardial fibrosis in a cohort with suspected cardiomyopathies. METHODS The proposed FB-MultiMap technique, enabling T2, T1ρ and their difference (myocardial fibrosis index, mFI) quantification in a single scan was developed in phantoms and 15 healthy subjects. In the clinical study, 55 patients with suspected cardiomyopathies were imaged using FB-MultiMap, conventional native T1 mapping, LGE, and ECV imaging. The accuracy of the endogenous parameters for predicting increased ECV was evaluated using receiver operating characteristic (ROC) curve analysis. In addition, the correlation of native T1, T1ρ, and mFI with ECV was respectively assessed using Pearson correlation coefficients. RESULTS FB-MultiMap showed a good agreement with conventional separate breath-hold mapping techniques in phantoms and healthy subjects. Considering all the patients, T1ρ was more accurate than mFI and native T1 for predicting increased ECV, with area under the curve (AUC) values of 0.91, 0.79 and 0.75, respectively, and showed stronger correlation with ECV (correlation coefficient r: 0.72 vs. 0.52 vs. 0.40). In the subset of 47 patients with normal T2 values, the diagnostic performance of mFI was significantly strengthened (AUC=0.90, r=0.83), outperforming T1ρ and native T1. CONCLUSION The proposed free-breathing T1ρ dispersion imaging technique enabling simultaneous quantification of T2, T1ρ and mFI in a single scan has shown great potential for diagnosing diffuse myocardial fibrosis in patients with complex cardiomyopathies without contrast agents.
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Affiliation(s)
- Qinfang Miao
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Sha Hua
- Department of Cardiovascular Medicine, Heart Failure Center, Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yiwen Gong
- Department of Cardiovascular Medicine, Heart Failure Center, Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhenfeng Lyu
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Pengfang Qian
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Chun Liu
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Wei Jin
- Department of Cardiovascular Medicine, Heart Failure Center, Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Peng Hu
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Haikun Qi
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, China; Shanghai Clinical Research and Trial Center, Shanghai, China.
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Ai QYH, King AD, Tsang YM, Yu Z, Mao K, Mo FKF, Wong LM, Leung HS, So TY, Hui EP, Ma BBY, Chen W. Predictive markers for head and neck cancer treatment response: T1rho imaging in nasopharyngeal carcinoma. Eur Radiol 2024:10.1007/s00330-024-10948-5. [PMID: 39191996 DOI: 10.1007/s00330-024-10948-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/14/2024] [Accepted: 06/20/2024] [Indexed: 08/29/2024]
Abstract
OBJECTIVES To investigate the potential of T1rho, a new quantitative imaging sequence for cancer, for pre and early intra-treatment prediction of treatment response in nasopharyngeal carcinoma (NPC) and compare the results with those of diffusion-weighted imaging (DWI). MATERIALS AND METHODS T1rho and DWI imaging of primary NPCs were performed pre- and early intra-treatment in 41 prospectively recruited patients. The mean preT1rho, preADC, intraT1rho, intraADC, and % changes in T1rho (ΔT1rho%) and ADC (ΔADC%) were compared between residual and non-residual groups based on biopsy in all patients after chemoradiotherapy (CRT) with (n = 29) or without (n = 12) induction chemotherapy (IC), and between responders and non-responders to IC in the subgroup who received IC, using Mann-Whitney U-test. A p-value of < 0.05 indicated statistical significance. RESULTS Significant early intra-treatment changes in mean T1rho (p = 0.049) and mean ADC (p < 0.01) were detected (using paired t-test), most showing a decrease in T1rho (63.4%) and an increase in ADC (95.1%). Responders to IC (n = 17), compared to non-responders (n = 12), showed higher preT1rho (64.0 ms vs 66.5 ms) and a greater decrease in ΔT1rho% (- 7.5% vs 1.3%) (p < 0.05). The non-residual group after CRT (n = 35), compared to the residual group (n = 6), showed higher intraADC (0.96 vs 1.09 × 10-3 mm2/s) and greater increase in ΔADC% (11.7% vs 27.0%) (p = 0.02). CONCLUSION Early intra-treatment changes are detectable on T1rho and show potential to predict tumour shrinkage after IC. T1rho may be complementary to DWI, which, unlike T1rho, did not predict response to IC but did predict non-residual disease after CRT. CLINICAL RELEVANCE STATEMENT T1rho has the potential to complement DWI in the prediction of treatment response. Unlike DWI, it predicted shrinkage of the primary NPC after IC but not residual disease after CRT. KEY POINTS Changes in T1rho were detected early during cancer treatment for NPC. Pre-treatment and early intra-treatment change in T1rho predicted response to IC, but not residual disease after CRT. T1rho can be used to complement DWI with DWI predicting residual disease after CRT.
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Affiliation(s)
- Qi Yong H Ai
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong S.A.R., P.R. China
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Ann D King
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China.
| | - Yip Man Tsang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Ziqiang Yu
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Kaijing Mao
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong S.A.R., P.R. China
| | - Frankie K F Mo
- Department of Clinical Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
- State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Hong Kong S.A.R., P.R. China
| | - Lun M Wong
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Ho Sang Leung
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Tiffany Y So
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Edwin P Hui
- Department of Clinical Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
- State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Hong Kong S.A.R., P.R. China
- Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Brigette B Y Ma
- Department of Clinical Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
- State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Hong Kong S.A.R., P.R. China
- Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
| | - Weitian Chen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong S.A.R., P.R. China
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Han C, Xu H, Gao H, Liu F, Wu J, Liu Y, Cheng Y, Deng W, Yue X, Wu Z, Yu Y, Zhao R, Han Y, Li X. Effect of spin-lock frequency on quantitative myocardial T1ρ mapping. Insights Imaging 2024; 15:176. [PMID: 38992330 PMCID: PMC11239636 DOI: 10.1186/s13244-024-01762-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 06/24/2024] [Indexed: 07/13/2024] Open
Abstract
OBJECTIVES To use T1ρ mapping to assess myocardial fibrosis and to provide a reference for future clinical application, it is necessary to understand the factors influencing T1ρ values. This study explored the influence of different spin-locking frequencies on T1ρ values under a 3.0-T MR system. METHODS Fifty-seven healthy subjects were prospectively and consecutively included in this study, and T1ρ mapping was performed on them in 3 short-axis slices with three spin-lock frequencies at the amplitude of 300 Hz, 400 Hz, and 500 Hz, then nine T1ρ images were acquired per subject. Four T1ρ-weighted images were acquired using a spin-lock preparation pulse with varying durations (0 msec, 13.3 msec, 26.6 msec, 40 msec). T1ρ relaxation times were quantified for each slice and each myocardial segment. The results were analyzed using Student's t-test and one-way analysis of variance (ANOVA) methods. RESULTS Mean T1ρ relaxation times were 43.5 ± 2.8 msec at 300 Hz, 44.9 ± 3.6 msec at 400 Hz, and 46.2 ± 3.1 msec at 500 Hz, showing a significant progressive increase from low to high spin-lock frequency (300 Hz vs. 400 Hz, p = 0.046; 300 Hz vs. 500 Hz, p < 0.001; 400 Hz vs. 500 Hz, p = 0.043). In addition, The T1ρ values of females were significantly higher than those of males (300 Hz, p = 0.049; 400 Hz, p = 0.01; 500 Hz, p = 0.002). CONCLUSION In this prospective study, myocardial T1ρ values for the specific CMR setting are provided, and we found that gender and spin-lock frequency can affect the T1ρ values. CRITICAL RELEVANCE STATEMENT T1ρ mapping could supersede late gadolinium enhancement for detection of myocardial fibrosis. Establishing reference mean values that take key technical elements into account will facilitate interpretation of data in disease states. KEY POINTS This study established myocardial T1ρ reference values for different spin-lock frequencies. T1ρ values increased with spin-lock frequency, but numerical differences were minimal. Females had higher T1ρ values than males at all frequencies.
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Affiliation(s)
- Caiyun Han
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | - Huimin Xu
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | - Hui Gao
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | - Fang Liu
- Department of Cardiology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, 230022, Hefei, China
| | - Jian Wu
- Department of Cardiology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, 230022, Hefei, China
| | - Yan Liu
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | - Yong Cheng
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | - Wei Deng
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China
| | | | | | - Yongqiang Yu
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China.
| | - Ren Zhao
- Department of Cardiology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, 230022, Hefei, China.
| | - Yuchi Han
- Cardiovascular Division, Wexner Medical Center, College of Medicine, the Ohio State University Medical Center, Columbus, Ohio, USA
| | - Xiaohu Li
- Department of Radiology, the First Affiliated Hospital of Anhui Medical University; Research Center of Clinical Medical Imaging; Anhui Province Clinical Image Quality Control Center, Hefei, 230032, Anhui Province, China.
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Deng W, Wang Z, Jia Z, Liu F, Wu J, Yang J, An S, Yu Y, Han Y, Zhao R, Li X. Cardiac T1ρ Mapping Values Affected by Age and Sex in a Healthy Chinese Cohort. J Magn Reson Imaging 2024. [PMID: 38168067 DOI: 10.1002/jmri.29196] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/04/2023] [Accepted: 12/05/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND To facilitate the clinical use of cardiac T1ρ, it is important to understand the impact of age and sex on T1ρ values of the myocardium. PURPOSE To investigate the impact of age and gender on myocardial T1ρ values. STUDY TYPE Cross-sectional. POPULATION Two hundred ten healthy Han Chinese volunteers without cardiovascular risk factors (85 males, mean age 34.4 ± 12.5 years; 125 females, mean age 37.9 ± 14.8 years). FIELD STRENGTH/SEQUENCE 1.5 T; T1ρ-prepared steady-state free precession (T1ρ mapping) sequence. ASSESSMENT Basal, mid, and apical short-axis left ventricular T1ρ maps were acquired. T1ρ maps acquired with spin-lock frequencies of 5 and 400 Hz were subtracted to create a myocardial fibrosis index (mFI) map. T1ρ and mFI values across different age decades, sex, and slice locations were compared. STATISTICAL TESTS Shapiro-Wilk test, Student's t test, Mann-Whitney U test, linear regression analysis, one-way analysis of variance and intraclass correlation coefficient. SIGNIFICANCE P value <0.05. RESULTS Women had significantly higher T1ρ and mFI values than men (50.3 ± 2.0 msec vs. 47.7 ± 2.4 msec and 4.7 ± 1.0 msec vs. 4.3 ± 1.1 msec, respectively). Additionally, in males and females combined, there was a significant positive but weak correlation between T1ρ values and age (r = 0.27), while no correlation was observed between the mFI values and age (P = 0.969). DATA CONCLUSION We report potential reference values for cardiac T1ρ by sex, age distribution, and slice location in a Chinese population. T1ρ was significantly correlated with age and sex, while mFI was only associated with sex. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Wei Deng
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
| | - Zhen Wang
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
| | - Zhuoran Jia
- Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Fang Liu
- Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Jian Wu
- Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Jinxiu Yang
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
| | - Shutian An
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
| | - Yongqiang Yu
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
| | - Yuchi Han
- Cardiovascular Division, Wexner Medical Center, College of Medicine, The Ohio State University Medical Center, Columbus, Ohio, USA
| | - Ren Zhao
- Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Xiaohu Li
- Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Research Center of Clinical Medical Imaging, Anhui Province Clinical Image Quality Control Center, Hefei, Anhui, China
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Lyu Z, Hua S, Xu J, Shen Y, Guo R, Hu P, Qi H. Free-breathing simultaneous native myocardial T1, T2 and T1ρ mapping with Cartesian acquisition and dictionary matching. J Cardiovasc Magn Reson 2023; 25:63. [PMID: 37946191 PMCID: PMC10636995 DOI: 10.1186/s12968-023-00973-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 10/20/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND T1, T2 and T1ρ are well-recognized parameters for quantitative cardiac MRI. Simultaneous estimation of these parameters allows for comprehensive myocardial tissue characterization, such as myocardial fibrosis and edema. However, conventional techniques either quantify the parameters individually with separate breath-hold acquisitions, which may result in unregistered parameter maps, or estimate multiple parameters in a prolonged breath-hold acquisition, which may be intolerable to patients. We propose a free-breathing multi-parametric mapping (FB-MultiMap) technique that provides co-registered myocardial T1, T2 and T1ρ maps in a single efficient acquisition. METHODS The proposed FB-MultiMap performs electrocardiogram-triggered single-shot Cartesian acquisition over 16 consecutive cardiac cycles, where inversion, T2 and T1ρ preparations are introduced for varying contrasts. A diaphragmatic navigator was used for prospective through-plane motion correction and the in-plane motion was corrected retrospectively with a group-wise image registration method. Quantitative mapping was conducted through dictionary matching of the motion corrected images, where the subject-specific dictionary was created using Bloch simulations for a range of T1, T2 and T1ρ values, as well as B1 factors to account for B1 inhomogeneities. The FB-MultiMap was optimized and validated in numerical simulations, phantom experiments, and in vivo imaging of 15 healthy subjects and six patients with suspected cardiac diseases. RESULTS The phantom T1, T2 and T1ρ values estimated with FB-MultiMap agreed well with reference measurements with no dependency on heart rate. In healthy subjects, FB-MultiMap T1 was higher than MOLLI T1 mapping (1218 ± 50 ms vs. 1166 ± 38 ms, p < 0.001). The myocardial T2 and T1ρ estimated with FB-MultiMap were lower compared to the mapping with T2- or T1ρ-prepared 2D balanced steady-state free precession (T2: 41.2 ± 2.8 ms vs. 42.5 ± 3.1 ms, p = 0.06; T1ρ: 45.3 ± 4.4 ms vs. 50.2 ± 4.0, p < 0.001). The pathological changes in myocardial parameters measured with FB-MultiMap were consistent with conventional techniques in all patients. CONCLUSION The proposed free-breathing multi-parametric mapping technique provides co-registered myocardial T1, T2 and T1ρ maps in 16 heartbeats, achieving similar mapping quality to conventional breath-hold mapping methods.
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Affiliation(s)
- Zhenfeng Lyu
- School of Biomedical Engineering, ShanghaiTech University, 4th Floor, BME Building, 393 Middle Huaxia Road, Pudong District, Shanghai, 201210, China
- Shanghai Clinical Research and Trial Center, Shanghai, China
| | - Sha Hua
- Department of Cardiovascular Medicine, Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian Xu
- UIH America, Inc., Houston, TX, USA
| | - Yiwen Shen
- Department of Cardiovascular Medicine, Ruijin Hospital Lu Wan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Rui Guo
- School of Medical Technology, Beijing Institute of Technology, Beijing, China
| | - Peng Hu
- School of Biomedical Engineering, ShanghaiTech University, 4th Floor, BME Building, 393 Middle Huaxia Road, Pudong District, Shanghai, 201210, China.
- Shanghai Clinical Research and Trial Center, Shanghai, China.
| | - Haikun Qi
- School of Biomedical Engineering, ShanghaiTech University, 4th Floor, BME Building, 393 Middle Huaxia Road, Pudong District, Shanghai, 201210, China.
- Shanghai Clinical Research and Trial Center, Shanghai, China.
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Coletti C, Fotaki A, Tourais J, Zhao Y, van de Steeg-Henzen C, Akçakaya M, Tao Q, Prieto C, Weingärtner S. Robust cardiac T 1 ρ $$ {\mathrm{T}}_{1_{\boldsymbol{\rho}}} $$ mapping at 3T using adiabatic spin-lock preparations. Magn Reson Med 2023; 90:1363-1379. [PMID: 37246420 PMCID: PMC10984724 DOI: 10.1002/mrm.29713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 04/26/2023] [Accepted: 05/04/2023] [Indexed: 05/30/2023]
Abstract
PURPOSE The aim of this study is to develop and optimize an adiabaticT 1 ρ $$ {\mathrm{T}}_{1\uprho} $$ (T 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ ) mapping method for robust quantification of spin-lock (SL) relaxation in the myocardium at 3T. METHODS Adiabatic SL (aSL) preparations were optimized for resilience againstB 0 $$ {\mathrm{B}}_0 $$ andB 1 + $$ {\mathrm{B}}_1^{+} $$ inhomogeneities using Bloch simulations. OptimizedB 0 $$ {\mathrm{B}}_0 $$ -aSL, Bal-aSL andB 1 $$ {\mathrm{B}}_1 $$ -aSL modules, each compensating for different inhomogeneities, were first validated in phantom and human calf. MyocardialT 1 ρ $$ {\mathrm{T}}_{1\uprho} $$ mapping was performed using a single breath-hold cardiac-triggered bSSFP-based sequence. Then, optimizedT 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ preparations were compared to each other and to conventional SL-preparedT 1 ρ $$ {\mathrm{T}}_{1\uprho} $$ maps (RefSL) in phantoms to assess repeatability, and in 13 healthy subjects to investigate image quality, precision, reproducibility and intersubject variability. Finally, aSL and RefSL sequences were tested on six patients with known or suspected cardiovascular disease and compared with LGE,T 1 $$ {\mathrm{T}}_1 $$ , and ECV mapping. RESULTS The highestT 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ preparation efficiency was obtained in simulations for modules comprising 2 HS pulses of 30 ms each. In vivoT 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ maps yielded significantly higher quality than RefSL maps. Average myocardialT 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ values were 183.28± $$ \pm $$ 25.53 ms, compared with 38.21± $$ \pm $$ 14.37 ms RefSL-preparedT 1 ρ $$ {\mathrm{T}}_{1\uprho} $$ .T 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ maps showed a significant improvement in precision (avg. 14.47± $$ \pm $$ 3.71% aSL, 37.61± $$ \pm $$ 19.42% RefSL, p < 0.01) and reproducibility (avg. 4.64± $$ \pm $$ 2.18% aSL, 47.39± $$ \pm $$ 12.06% RefSL, p < 0.0001), with decreased inter-subject variability (avg. 8.76± $$ \pm $$ 3.65% aSL, 51.90± $$ \pm $$ 15.27% RefSL, p < 0.0001). Among aSL preparations,B 0 $$ {\mathrm{B}}_0 $$ -aSL achieved the better inter-subject variability. In patients,B 1 $$ {\mathrm{B}}_1 $$ -aSL preparations showed the best artifact resilience among the adiabatic preparations.T 1 ρ , adiab $$ {\mathrm{T}}_{1\uprho, \mathrm{adiab}} $$ times show focal alteration colocalized with areas of hyper-enhancement in the LGE images. CONCLUSION Adiabatic preparations enable robust in vivo quantification of myocardial SL relaxation times at 3T.
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Affiliation(s)
- Chiara Coletti
- Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Anastasia Fotaki
- Department of Biomedical Engineering, King’s College London, London, United Kingdom
| | - Joao Tourais
- Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Yidong Zhao
- Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | | | - Mehmet Akçakaya
- Department of Electrical and Computer Engineering and Center for Magnetic Resonance Research, University of Minnesota, Minnesota, USA
| | - Qian Tao
- Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Claudia Prieto
- Department of Biomedical Engineering, King’s College London, London, United Kingdom
- School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
- Milleniun Institute for Intelligent Healthcare Engineering, Santiago, Chile
| | - Sebastian Weingärtner
- Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
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Yang Y, Wang C, Liu Y, Chen Z, Liu X, Zheng H, Liang D, Zhu Y. A robust adiabatic constant amplitude spin-lock preparation module for myocardial T 1ρ quantification at 3 T. NMR IN BIOMEDICINE 2023; 36:e4830. [PMID: 36093600 DOI: 10.1002/nbm.4830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 08/25/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
T1ρ quantification has the potential to assess myocardial fibrosis without contrast agent. However, its preparation spin-lock pulse is sensitive to B1 and B0 inhomogeneities, resulting in severe banding artifacts in the heart region, especially at high magnetic field such as 3 T. We aimed to design a robust spin-lock (SL) preparation module that can be used in myocardial T1ρ quantification at 3 T. We used the tan/tanh pulse to tip up and tip down the magnetization in the spin-lock preparation module (tan/tanh-SL). Bloch simulation was used to optimize pulse shape parameters of the tan/tanh with a pulse duration (Tp ) of 8, 4, and 2 ms, respectively. The designed tan/tanh-SL modules were implemented on a 3-T MR scanner. They were evaluated in phantom studies under three different cases of B0 and B1 inhomogeneities, and tested in cardiac T1ρ quantification of healthy volunteers. The performance of the tan/tanh-SL was compared with the composite SL preparation pulses and the commonly used hyperbolic secant pulse for spin-lock (HS-SL). Feasible pulse shape parameters were obtained using Bloch simulation. Compared with HS-SL, the quantification error of tan/tanh-SL was reduced by 27.7% for Tp = 8 ms (mean ∆Q = 126.15 vs. 174.42) and 75.6% for Tp = 4 ms (mean ∆Q = 136.65 vs. 559.53). In the phantom study, tan/tanh-SL was less sensitive to B1 and B0 inhomogeneity compared with composite SL pulses and HS-SL. In cardiac T1ρ quantification, the T1ρ maps using tan/tanh-SL showed fewer banding artifacts than using composite SL pulses and HS-SL. The proposed tan/tanh-SL preparation module greatly improves the robustness to B0 and B1 field inhomogeneities and can be used in cardiac T1ρ quantification at 3 T.
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Affiliation(s)
- Yuxin Yang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- Department of Biomedical Engineering, Chongqing University of Technology, Chongqing, China
| | - Che Wang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- Department of Biomedical Engineering, Chongqing University of Technology, Chongqing, China
| | - Yuanyuan Liu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Zhongmin Chen
- Department of Biomedical Engineering, Chongqing University of Technology, Chongqing, China
| | - Xin Liu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Hairong Zheng
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Dong Liang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Yanjie Zhu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
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8
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Fotaki A, Velasco C, Prieto C, Botnar RM. Quantitative MRI in cardiometabolic disease: From conventional cardiac and liver tissue mapping techniques to multi-parametric approaches. Front Cardiovasc Med 2023; 9:991383. [PMID: 36756640 PMCID: PMC9899858 DOI: 10.3389/fcvm.2022.991383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 12/29/2022] [Indexed: 01/24/2023] Open
Abstract
Cardiometabolic disease refers to the spectrum of chronic conditions that include diabetes, hypertension, atheromatosis, non-alcoholic fatty liver disease, and their long-term impact on cardiovascular health. Histological studies have confirmed several modifications at the tissue level in cardiometabolic disease. Recently, quantitative MR methods have enabled non-invasive myocardial and liver tissue characterization. MR relaxation mapping techniques such as T1, T1ρ, T2 and T2* provide a pixel-by-pixel representation of the corresponding tissue specific relaxation times, which have been shown to correlate with fibrosis, altered tissue perfusion, oedema and iron levels. Proton density fat fraction mapping approaches allow measurement of lipid tissue in the organ of interest. Several studies have demonstrated their utility as early diagnostic biomarkers and their potential to bear prognostic implications. Conventionally, the quantification of these parameters by MRI relies on the acquisition of sequential scans, encoding and mapping only one parameter per scan. However, this methodology is time inefficient and suffers from the confounding effects of the relaxation parameters in each single map, limiting wider clinical and research applications. To address these limitations, several novel approaches have been proposed that encode multiple tissue parameters simultaneously, providing co-registered multiparametric information of the tissues of interest. This review aims to describe the multi-faceted myocardial and hepatic tissue alterations in cardiometabolic disease and to motivate the application of relaxometry and proton-density cardiac and liver tissue mapping techniques. Current approaches in myocardial and liver tissue characterization as well as latest technical developments in multiparametric quantitative MRI are included. Limitations and challenges of these novel approaches, and recommendations to facilitate clinical validation are also discussed.
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Affiliation(s)
- Anastasia Fotaki
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom,*Correspondence: Anastasia Fotaki,
| | - Carlos Velasco
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Claudia Prieto
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom,School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile,Institute for Biological and Medical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile,Millennium Institute for Intelligent Healthcare Engineering, Santiago, Chile
| | - René M. Botnar
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom,School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile,Institute for Biological and Medical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile,Millennium Institute for Intelligent Healthcare Engineering, Santiago, Chile
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9
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Abstract
Myocardial inflammation occurs following activation of the cardiac immune system, producing characteristic changes in the myocardial tissue. Cardiovascular magnetic resonance is the non-invasive imaging gold standard for myocardial tissue characterization, and is able to detect image signal changes that may occur resulting from inflammation, including edema, hyperemia, capillary leak, necrosis, and fibrosis. Conventional cardiovascular magnetic resonance for the detection of myocardial inflammation and its sequela include T2-weighted imaging, parametric T1- and T2-mapping, and gadolinium-based contrast-enhanced imaging. Emerging techniques seek to image several parameters simultaneously for myocardial tissue characterization, and to depict subtle immune-mediated changes, such as immune cell activity in the myocardium and cardiac cell metabolism. This review article outlines the underlying principles of current and emerging cardiovascular magnetic resonance methods for imaging myocardial inflammation.
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Affiliation(s)
- Katharine E Thomas
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, United Kingdom (K.E.T., V.M.F.)
| | - Anastasia Fotaki
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, United Kingdom (A.F., R.M.B.)
| | - René M Botnar
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, United Kingdom (A.F., R.M.B.)
- Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile (R.M.B.)
- Millennium Institute for Intelligent Healthcare Engineering, Santiago, Chile (R.M.B.)
| | - Vanessa M Ferreira
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, United Kingdom (K.E.T., V.M.F.)
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10
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Qi H, Lv Z, Hu J, Xu J, Botnar R, Prieto C, Hu P. Accelerated 3D free-breathing high-resolution myocardial T 1ρ mapping at 3 Tesla. Magn Reson Med 2022; 88:2520-2531. [PMID: 36054715 DOI: 10.1002/mrm.29417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 07/18/2022] [Accepted: 07/27/2022] [Indexed: 11/08/2022]
Abstract
PURPOSE To develop a fast free-breathing whole-heart high-resolution myocardial T1ρ mapping technique with robust spin-lock preparation that can be performed at 3 Tesla. METHODS An adiabatically excited continuous-wave spin-lock module, insensitive to field inhomogeneities, was implemented with an electrocardiogram-triggered low-flip angle spoiled gradient echo sequence with variable-density 3D Cartesian undersampling at a 3 Tesla whole-body scanner. A saturation pulse was performed at the beginning of each cardiac cycle to null the magnetization before T1ρ preparation. Multiple T1ρ -weighted images were acquired with T1ρ preparations with different spin-lock times in an interleaved fashion. Respiratory self-gating approach was adopted along with localized autofocus to enable 3D translational motion correction of the data acquired in each heartbeat. After motion correction, multi-contrast locally low-rank reconstruction was performed to reduce undersampling artifacts. The accuracy and feasibility of the 3D T1ρ mapping technique was investigated in phantoms and in vivo in 10 healthy subjects compared with the 2D T1ρ mapping. RESULTS The 3D T1ρ mapping technique provided similar phantom T1ρ measurements in the range of 25-120 ms to the 2D T1ρ mapping reference over a wide range of simulated heart rates. With the robust adiabatically excited continuous-wave spin-lock preparation, good quality 2D and 3D in vivo T1ρ -weighted images and T1ρ maps were obtained. Myocardial T1ρ values with the 3D T1ρ mapping were slightly longer than 2D breath-hold measurements (septal T1ρ : 52.7 ± 1.4 ms vs. 50.2 ± 1.8 ms, P < 0.01). CONCLUSION A fast 3D free-breathing whole-heart T1ρ mapping technique was proposed for T1ρ quantification at 3 T with isotropic spatial resolution (2 mm3 ) and short scan time of ∼4.5 min.
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Affiliation(s)
- Haikun Qi
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, People's Republic of China
| | - Zhenfeng Lv
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, People's Republic of China
| | - Junpu Hu
- United Imaging Healthcare, Shanghai, People's Republic of China
| | - Jian Xu
- UIH America, Inc., Houston, Texas
| | - René Botnar
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.,Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Institute for Intelligent Healthcare Engineering, Santiago, Chile
| | - Claudia Prieto
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.,Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Institute for Intelligent Healthcare Engineering, Santiago, Chile
| | - Peng Hu
- School of Biomedical Engineering, ShanghaiTech University, Shanghai, People's Republic of China
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11
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Serai SD. Basics of magnetic resonance imaging and quantitative parameters T1, T2, T2*, T1rho and diffusion-weighted imaging. Pediatr Radiol 2022; 52:217-227. [PMID: 33856502 DOI: 10.1007/s00247-021-05042-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/18/2021] [Accepted: 03/01/2021] [Indexed: 01/27/2023]
Abstract
Magnetic resonance imaging is widely available and accepted as the imaging method of choice for many pediatric body imaging applications. Traditionally, it has been used in a qualitative way, where the images are reported non-numerically by radiologists. But now MRI machines have built-in post-processing software connected to the scanner and the database of MR images. This setting enables and encourages simple quantitative analysis of MR images. In this paper, the author reviews the fundamentals of MRI and discusses the most common quantitative MRI techniques for body imaging: T1, T2, T2*, T1rho and diffusion-weighted imaging (DWI). For each quantitative imaging method, this article reviews the technique, its measurement mechanism, and selected clinical applications to body imaging.
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Affiliation(s)
- Suraj D Serai
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA. .,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
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12
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Fast myocardial T 1ρ mapping in mice using k-space weighted image contrast and a Bloch simulation-optimized radial sampling pattern. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2021; 35:325-340. [PMID: 34491466 PMCID: PMC8995242 DOI: 10.1007/s10334-021-00951-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/17/2022]
Abstract
Purpose T1ρ dispersion quantification can potentially be used as a cardiac magnetic resonance index for sensitive detection of myocardial fibrosis without the need of contrast agents. However, dispersion quantification is still a major challenge, because T1ρ mapping for different spin lock amplitudes is a very time consuming process. This study aims to develop a fast and accurate T1ρ mapping sequence, which paves the way to cardiac T1ρ dispersion quantification within the limited measurement time of an in vivo study in small animals. Methods A radial spin lock sequence was developed using a Bloch simulation-optimized sampling pattern and a view-sharing method for image reconstruction. For validation, phantom measurements with a conventional sampling pattern and a gold standard sequence were compared to examine T1ρ quantification accuracy. The in vivo validation of T1ρ mapping was performed in N = 10 mice and in a reproduction study in a single animal, in which ten maps were acquired in direct succession. Finally, the feasibility of myocardial dispersion quantification was tested in one animal. Results The Bloch simulation-based sampling shows considerably higher image quality as well as improved T1ρ quantification accuracy (+ 56%) and precision (+ 49%) compared to conventional sampling. Compared to the gold standard sequence, a mean deviation of − 0.46 ± 1.84% was observed. The in vivo measurements proved high reproducibility of myocardial T1ρ mapping. The mean T1ρ in the left ventricle was 39.5 ± 1.2 ms for different animals and the maximum deviation was 2.1% in the successive measurements. The myocardial T1ρ dispersion slope, which was measured for the first time in one animal, could be determined to be 4.76 ± 0.23 ms/kHz. Conclusion This new and fast T1ρ quantification technique enables high-resolution myocardial T1ρ mapping and even dispersion quantification within the limited time of an in vivo study and could, therefore, be a reliable tool for improved tissue characterization. Supplementary Information The online version contains supplementary material available at 10.1007/s10334-021-00951-y.
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13
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Ai QYH, Zhang H, Jiang B, So TY, Mo FKF, Qamar S, Chen W, King AD. Test-retest repeatability of T1rho (T1ρ) MR imaging in the head and neck. Eur J Radiol 2020; 135:109489. [PMID: 33395595 DOI: 10.1016/j.ejrad.2020.109489] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/15/2020] [Accepted: 12/18/2020] [Indexed: 12/27/2022]
Abstract
PURPOSE T1rho imaging is a new quantitative MRI sequence for head and neck cancer and the repeatability for this region is unknown. This study aimed to evaluate the repeatability of quantitative T1rho imaging in the head and neck. MATERIALS AND METHODS T1rho imaging of the head and neck was prospectively performed in 15 healthy participants on three occasions. Scan 1 and 2 were performed with a time interval of 30 minutes (intra-session) and scan 3 was performed 14 days later (inter-session). T1rho values for normal tissues (parotid glands, palatine tonsils, pterygoid muscles, and tongue) were obtained on each scan. Intra-class coefficients (ICCs), within-subject coefficient of variances (wCoVs), and repeatability coefficient (RCs) of the intra-session scan (scan 1 vs 2) and inter-session scan (scan 1 vs 3) for the normal tissues were calculated. RESULTS The ICCs of T1rho values for normal tissues were almost perfect (0.83-0.97) for intra-session scans and were substantial (0.71-0.80) for inter-session scans. The wCoVs showed a small range (2.46%-3.30%) for intra-session scans, and slightly greater range (3.27%-6.51%) for inter-session scan. The greatest and lowest wCoVs of T1rho were found in the parotid gland and muscles, respectively. The T1rho RCs varied for all tissues between intra- and inter- sessions, and the greatest RC of 10.07 msec was observed for parotid gland on inter-session scan. CONCLUSION T1rho imaging is a repeatable quantitative MRI sequence in the head and neck but variances of T1rho values among tissues should be take into account during analysis.
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Affiliation(s)
- Qi Yong H Ai
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong.
| | - Huimin Zhang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Baiyan Jiang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Tiffany Y So
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Frankie K F Mo
- Department of Clinical Oncology, State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Sahrish Qamar
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Weitian Chen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
| | - Ann D King
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
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14
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Ai QYH, Chen W, So TY, Lam WKJ, Jiang B, Poon DMC, Qamar S, Mo FKF, Blu T, Chan Q, Ma BBY, Hui EP, Chan KCA, King AD. Quantitative T1ρ MRI of the Head and Neck Discriminates Carcinoma and Benign Hyperplasia in the Nasopharynx. AJNR Am J Neuroradiol 2020; 41:2339-2344. [PMID: 33122214 DOI: 10.3174/ajnr.a6828] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 08/07/2020] [Indexed: 12/25/2022]
Abstract
BACKGROUND AND PURPOSE T1ρ imaging is a new quantitative MR imaging pulse sequence with the potential to discriminate between malignant and benign tissue. In this study, we evaluated the capability of T1ρ imaging to characterize tissue by applying T1ρ imaging to malignant and benign tissue in the nasopharynx and to normal tissue in the head and neck. MATERIALS AND METHODS Participants with undifferentiated nasopharyngeal carcinoma and benign hyperplasia of the nasopharynx prospectively underwent T1ρ imaging. T1ρ measurements obtained from the histogram analysis for nasopharyngeal carcinoma in 43 participants were compared with those for benign hyperplasia and for normal tissue (brain, muscle, and parotid glands) in 41 participants using the Mann-Whitney U test. The area under the curve of significant T1ρ measurements was calculated and compared using receiver operating characteristic analysis and the Delong test, respectively. A P < . 05 indicated statistical significance. RESULTS There were significant differences in T1ρ measurements between nasopharyngeal carcinoma and benign hyperplasia and between nasopharyngeal carcinoma and normal tissue (all, P < . 05). Compared with benign hyperplasia, nasopharyngeal carcinoma showed a lower T1ρ mean (62.14 versus 65.45 × ms), SD (12.60 versus 17.73 × ms), and skewness (0.61 versus 0.76) (all P < .05), but no difference in kurtosis (P = . 18). The T1ρ SD showed the highest area under the curve of 0.95 compared with the T1ρ mean (area under the curve = 0.72) and T1ρ skewness (area under the curve = 0.72) for discriminating nasopharyngeal carcinoma and benign hyperplasia (all, P < .05). CONCLUSIONS Quantitative T1ρ imaging has the potential to discriminate malignant from benign and normal tissue in the head and neck.
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Affiliation(s)
- Q Y H Ai
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
| | - W Chen
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
| | - T Y So
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
| | - W K J Lam
- Li Ka Shing Institute of Health Sciences (W.K.J.L., D.M.C.P., B.B.Y.M., E.P.H., K.C.A.C.).,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.).,Department of Chemical Pathology (W.K.J.L., K.C.A.C.), State Key Laboratory in Oncology in South China, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, SAR
| | - B Jiang
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
| | - D M C Poon
- Li Ka Shing Institute of Health Sciences (W.K.J.L., D.M.C.P., B.B.Y.M., E.P.H., K.C.A.C.).,Department of Clinical Oncology (D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H.), State Key Laboratory in Oncology in South China, Sir Y.K. Pao Centre for Cancer, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR.,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.)
| | - S Qamar
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
| | - F K F Mo
- Department of Clinical Oncology (D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H.), State Key Laboratory in Oncology in South China, Sir Y.K. Pao Centre for Cancer, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR.,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.)
| | - T Blu
- Department of Electrical Engineering (T.B.), The Chinese University of Hong Kong, Hong Kong, SAR
| | - Q Chan
- Philips Healthcare (Q.C.), Hong Kong, SAR
| | - B B Y Ma
- Li Ka Shing Institute of Health Sciences (W.K.J.L., D.M.C.P., B.B.Y.M., E.P.H., K.C.A.C.).,Department of Clinical Oncology (D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H.), State Key Laboratory in Oncology in South China, Sir Y.K. Pao Centre for Cancer, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR.,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.)
| | - E P Hui
- Li Ka Shing Institute of Health Sciences (W.K.J.L., D.M.C.P., B.B.Y.M., E.P.H., K.C.A.C.).,Department of Clinical Oncology (D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H.), State Key Laboratory in Oncology in South China, Sir Y.K. Pao Centre for Cancer, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR.,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.)
| | - K C A Chan
- Li Ka Shing Institute of Health Sciences (W.K.J.L., D.M.C.P., B.B.Y.M., E.P.H., K.C.A.C.).,State Key Laboratory of Translational Oncology (W.K.J.L., D.M.C.P., F.K.F.M., B.B.Y.M., E.P.H., K.C.A.C.).,Department of Chemical Pathology (W.K.J.L., K.C.A.C.), State Key Laboratory in Oncology in South China, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, SAR
| | - A D King
- From the Department of Imaging and Interventional Radiology (Q.Y.H.A., W.C., T.Y.S., B.J., S.Q., A.D.K.)
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15
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Abstract
Ischemic heart disease is the most common cause of cardiovascular morbidity and mortality. Cardiac magnetic resonance (CMR) improves on other noninvasive modalities in detection, assessment, and prognostication of ischemic heart disease. The incorporation of CMR in clinical trials allows for smaller patient samples without the sacrifice of power needed to demonstrate clinical efficacy. CMR can accurately quantify infarct acuity, size, and complications; guide therapy; and prognosticate recovery. Timing of revascularization remains the holy grail of ischemic heart disease, and viability assessment using CMR may be the missing link needed to help reduce morbidity and mortality associated with the disease.
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Affiliation(s)
- Aneesh S Dhore-Patil
- Tulane University Heart and Vascular Center, Tulane University, 1415 Tulane Avenue, New Orleans, LA 70112, USA
| | - Ashish Aneja
- Department of Cardiovascular Diseases, Case Western Reserve University, MetroHealth Medical Center, 2500 MetroHealth Drive, Cleveland, OH 44109, USA.
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16
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López K, Neji R, Mukherjee RK, Whitaker J, Phinikaridou A, Razavi R, Prieto C, Roujol S, Botnar R. Contrast-free high-resolution 3D magnetization transfer imaging for simultaneous myocardial scar and cardiac vein visualization. MAGMA (NEW YORK, N.Y.) 2020; 33:627-640. [PMID: 32078075 PMCID: PMC7502043 DOI: 10.1007/s10334-020-00833-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 01/27/2020] [Accepted: 01/29/2020] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To develop a three-dimensional (3D) high-resolution free-breathing magnetization transfer ratio (MTR) sequence for contrast-free assessment of myocardial infarct and coronary vein anatomy. MATERIALS AND METHODS Two datasets with and without off-resonance magnetization transfer preparation were sequentially acquired to compute MTR. 2D image navigators enabled beat-to-beat translational and bin-to-bin non-rigid motion correction. Two different imaging sequences were explored. MTR scar localization was compared against 3D late gadolinium enhancement (LGE) in a porcine model of myocardial infarction. MTR variability across the left ventricle and vessel sharpness in the coronary veins were evaluated in healthy human subjects. RESULTS A decrease in MTR was observed in areas with LGE in all pigs (non-infarct: 25.1 ± 1.7% vs infarct: 16.8 ± 1.9%). The average infarct volume overlap on MTR and LGE was 62.5 ± 19.2%. In humans, mean MTR in myocardium was between 37 and 40%. Spatial variability was between 15 and 20% of the mean value. 3D whole heart MT-prepared datasets enabled coronary vein visualization with up to 8% improved vessel sharpness for non-rigid compared to translational motion correction. DISCUSSION MTR and LGE showed agreement in infarct detection and localization in a swine model. Free-breathing 3D MTR maps are feasible in humans but high spatial variability was observed. Further clinical studies are warranted.
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Affiliation(s)
- Karina López
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK.
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
- MR Research Collaborations, Siemens Healthcare Limited, Frimley, UK
| | - Rahul K Mukherjee
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - Alkystis Phinikaridou
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - Claudia Prieto
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - Sébastien Roujol
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
| | - René Botnar
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, 3rd Floor Lambeth Wing, London, SE1 7EH, UK
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17
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Qi H, Bustin A, Kuestner T, Hajhosseiny R, Cruz G, Kunze K, Neji R, Botnar RM, Prieto C. Respiratory motion-compensated high-resolution 3D whole-heart T1ρ mapping. J Cardiovasc Magn Reson 2020; 22:12. [PMID: 32014001 PMCID: PMC6998259 DOI: 10.1186/s12968-020-0597-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 01/03/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Cardiovascular magnetic resonance (CMR) T1ρ mapping can be used to detect ischemic or non-ischemic cardiomyopathy without the need of exogenous contrast agents. Current 2D myocardial T1ρ mapping requires multiple breath-holds and provides limited coverage. Respiratory gating by diaphragmatic navigation has recently been exploited to enable free-breathing 3D T1ρ mapping, which, however, has low acquisition efficiency and may result in unpredictable and long scan times. This study aims to develop a fast respiratory motion-compensated 3D whole-heart myocardial T1ρ mapping technique with high spatial resolution and predictable scan time. METHODS The proposed electrocardiogram (ECG)-triggered T1ρ mapping sequence is performed under free-breathing using an undersampled variable-density 3D Cartesian sampling with spiral-like order. Preparation pulses with different T1ρ spin-lock times are employed to acquire multiple T1ρ-weighted images. A saturation prepulse is played at the start of each heartbeat to reset the magnetization before T1ρ preparation. Image navigators are employed to enable beat-to-beat 2D translational respiratory motion correction of the heart for each T1ρ-weighted dataset, after which, 3D translational registration is performed to align all T1ρ-weighted volumes. Undersampled reconstruction is performed using a multi-contrast 3D patch-based low-rank algorithm. The accuracy of the proposed technique was tested in phantoms and in vivo in 11 healthy subjects in comparison with 2D T1ρ mapping. The feasibility of the proposed technique was further investigated in 3 patients with suspected cardiovascular disease. Breath-hold late-gadolinium enhanced (LGE) images were acquired in patients as reference for scar detection. RESULTS Phantoms results revealed that the proposed technique provided accurate T1ρ values over a wide range of simulated heart rates in comparison to a 2D T1ρ mapping reference. Homogeneous 3D T1ρ maps were obtained for healthy subjects, with septal T1ρ of 58.0 ± 4.1 ms which was comparable to 2D breath-hold measurements (57.6 ± 4.7 ms, P = 0.83). Myocardial scar was detected in 1 of the 3 patients, and increased T1ρ values (87.4 ± 5.7 ms) were observed in the infarcted region. CONCLUSIONS An accelerated free-breathing 3D whole-heart T1ρ mapping technique was developed with high respiratory scan efficiency and near-isotropic spatial resolution (1.7 × 1.7 × 2 mm3) in a clinically feasible scan time of ~ 6 mins. Preliminary patient results suggest that the proposed technique may find applications in non-contrast myocardial tissue characterization.
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Affiliation(s)
- Haikun Qi
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK.
| | - Aurelien Bustin
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
| | - Thomas Kuestner
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
| | - Reza Hajhosseiny
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
| | - Gastao Cruz
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
| | - Karl Kunze
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
- Siemens Healthcare, MR Research Collaborations, Frimley, UK
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
- Siemens Healthcare, MR Research Collaborations, Frimley, UK
| | - René M Botnar
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
- Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudia Prieto
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, Lambeth Palace Rd, London, SE1 7EH, UK
- Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile
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Jiang B, Chen W. On-resonance and off-resonance continuous wave constant amplitude spin-lock and T 1ρ quantification in the presence of B 1 and B 0 inhomogeneities. NMR IN BIOMEDICINE 2018; 31:e3928. [PMID: 29693744 DOI: 10.1002/nbm.3928] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 02/06/2018] [Accepted: 03/06/2018] [Indexed: 06/08/2023]
Abstract
Spin-lock MRI is a valuable diagnostic imaging technology, as it can be used to probe the macromolecule environment of tissues. Quantitative T1ρ imaging is one application of spin-lock MRI that is reported to be promising for a number of clinical applications. Spin-lock is often performed with a continuous RF wave at a constant RF amplitude either on resonance or off resonance. However, both on- and off-resonance spin-lock approaches are susceptible to B1 and B0 inhomogeneities, which results in image artifacts and quantification errors. In this work, we report a continuous wave constant amplitude spin-lock approach that can achieve negligible image artifacts in the presence of B1 and B0 inhomogeneities for both on- and off-resonance spin-lock. Under the adiabatic condition, by setting the maximum B1 amplitude of the adiabatic pulses equal to the B1 amplitude of spin-lock RF pulse, the spins are ensured to align along the effective field throughout the spin-lock process. We show that this results in simultaneous compensation of B1 and B0 inhomogeneities for both on- and off-resonance spin-lock. The relaxation effect during the entire adiabatic half passage (AHP) and reverse AHP, and the stationary solution of the Bloch-McConnell equation present at off-resonance frequency offset, are considered in the revised relaxation model. We demonstrate that these factors create a direct current component to the conventional relaxation model. In contrast to the previously reported dual-acquisition method, the revised relaxation model just requires one acquisition to perform quantification. The simulation, phantom, and in vivo experiments demonstrate that the proposed approach achieves superior image quality compared with the existing methods, and the revised relaxation model can perform T1ρ quantification with one acquisition instead of two.
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Affiliation(s)
- Baiyan Jiang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China
| | - Weitian Chen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China
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Yla-Herttuala E, Laidinen S, Laakso H, Liimatainen T. Quantification of myocardial infarct area based on T RAFFn relaxation time maps - comparison with cardiovascular magnetic resonance late gadolinium enhancement, T 1ρ and T 2 in vivo. J Cardiovasc Magn Reson 2018; 20:34. [PMID: 29879996 PMCID: PMC5992705 DOI: 10.1186/s12968-018-0463-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 05/24/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Two days after myocardial infarction (MI), the infarct consists mostly on necrotic tissue, and the myocardium is transformed through granulation tissue to scar in two weeks after the onset of ischemia in mice. In the current work, we determined and optimized cardiovascular magnetic resonance (CMR) methods for the detection of MI size during the scar formation without contrast agents in mice. METHODS We characterized MI and remote areas with rotating frame relaxation time mapping including relaxation along fictitious field in nth rotating frame (RAFFn), T1ρ and T2 relaxation time mappings at 1, 3, 7, and 21 days after MI. These results were compared to late gadolinium enhancement (LGE) and Sirius Red-stained histology sections, which were obtained at day 21 after MI. RESULTS All relaxation time maps showed significant differences in relaxation time between the MI and remote area. Areas of increased signal intensities after gadolinium injection and areas with increased TRAFF2 relaxation time were highly correlated with the MI area determined from Sirius Red-stained histology sections (LGE: R2 = 0.92, P < 0.01, TRAFF2: R2 = 0.95, P < 0.001). Infarct area determined based on T1ρ relaxation time correlated highly with Sirius Red histology sections (R2 = 0.97, P < 0.01). The smallest overestimation of the LGE-defined MI area was obtained for TRAFF2 (5.6 ± 4.2%) while for T1ρ overestimation percentage was > 9% depending on T1ρ pulse power. CONCLUSION T1ρ and TRAFF2 relaxation time maps can be used to determine accurately MI area at various time points in the mouse heart. Determination of MI size based on TRAFF2 relaxation time maps could be performed without contrast agents, unlike LGE, and with lower specific absorption rate compared to on-resonance T1ρ relaxation time mapping.
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Affiliation(s)
- Elias Yla-Herttuala
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Svetlana Laidinen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Hanne Laakso
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- Center for Magnetic Resonance Research, Minneapolis, MN USA
| | - Timo Liimatainen
- Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, University Hospital of Oulu, P.O. Box 50, 90029 OYS Oulu, Finland
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20
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Lottonen-Raikaslehto L, Rissanen R, Gurzeler E, Merentie M, Huusko J, Schneider JE, Liimatainen T, Ylä-Herttuala S. Left ventricular remodeling leads to heart failure in mice with cardiac-specific overexpression of VEGF-B 167: echocardiography and magnetic resonance imaging study. Physiol Rep 2017; 5:5/6/e13096. [PMID: 28351964 PMCID: PMC5371547 DOI: 10.14814/phy2.13096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 10/07/2016] [Accepted: 11/20/2016] [Indexed: 01/24/2023] Open
Abstract
Cardiac-specific overexpression of vascular endothelial growth factor (VEGF)-B167 is known to induce left ventricular hypertrophy due to altered lipid metabolism, in which ceramides accumulate to the heart and cause mitochondrial damage. The aim of this study was to evaluate and compare different imaging methods to find the most sensitive way to diagnose at early stage the progressive left ventricular remodeling leading to heart failure. Echocardiography and cardiovascular magnetic resonance imaging were compared for imaging the hearts of transgenic mice with cardiac-specific overexpression of VEGF-B167 and wild-type mice from 5 to 14 months of age at several time points. Disease progression was verified by molecular biology methods and histology. We showed that left ventricular remodeling is already ongoing at the age of 5 months in transgenic mice leading to heart failure by the age of 14 months. Measurements from echocardiography and cardiovascular magnetic resonance imaging revealed similar changes in cardiac structure and function in the transgenic mice. Changes in histology, gene expressions, and electrocardiography supported the progression of left ventricular hypertrophy. Longitudinal relaxation time in rotating frame (T1ρ ) in cardiovascular magnetic resonance imaging could be suitable for detecting severe fibrosis in the heart. We conclude that cardiac-specific overexpression of VEGF-B167 leads to left ventricular remodeling at early age and is a suitable model to study heart failure development with different imaging methods.
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Affiliation(s)
- Line Lottonen-Raikaslehto
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Riina Rissanen
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Erika Gurzeler
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Mari Merentie
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jenni Huusko
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jurgen E Schneider
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, United kingdom
| | - Timo Liimatainen
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.,Clinical Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Seppo Ylä-Herttuala
- Department of Biotechnology and Molecular Medicine, A. I. Virtanen Institute for Molecular Sciences, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland .,Gene Therapy Unit, Kuopio University Hospital, Kuopio, Finland.,Heart Center, Kuopio University Hospital, Kuopio, Finland
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21
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Weingärtner S, Moeller S, Schmitter S, Auerbach E, Kellman P, Shenoy C, Akçakaya M. Simultaneous multislice imaging for native myocardial T 1 mapping: Improved spatial coverage in a single breath-hold. Magn Reson Med 2017; 78:462-471. [PMID: 28580583 PMCID: PMC5509494 DOI: 10.1002/mrm.26770] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 04/10/2017] [Accepted: 05/06/2017] [Indexed: 01/02/2023]
Abstract
PURPOSE To develop a saturation recovery myocardial T1 mapping method for the simultaneous multislice acquisition of three slices. METHODS Saturation pulse-prepared heart rate independent inversion recovery (SAPPHIRE) T1 mapping was implemented with simultaneous multislice imaging using FLASH readouts for faster coverage of the myocardium. Controlled aliasing in parallel imaging (CAIPI) was used to achieve minimal noise amplification in three slices. Multiband reconstruction was performed using three linear reconstruction methods: Slice- and in-plane GRAPPA, CG-SENSE, and Tikhonov-regularized CG-SENSE. Accuracy, spatial variability, and interslice leakage were compared with single-band T1 mapping in a phantom and in six healthy subjects. RESULTS Multiband phantom T1 times showed good agreement with single-band T1 mapping for all three reconstruction methods (normalized root mean square error <1.0%). The increase in spatial variability compared with single-band imaging was lowest for GRAPPA (1.29-fold), with higher penalties for Tikhonov-regularized CG-SENSE (1.47-fold) and CG-SENSE (1.52-fold). In vivo multiband T1 times showed no significant difference compared with single-band (T1 time ± intersegmental variability: single-band, 1580 ± 119 ms; GRAPPA, 1572 ± 145 ms; CG-SENSE, 1579 ± 159 ms; Tikhonov, 1586 ± 150 ms [analysis of variance; P = 0.86]). Interslice leakage was smallest for GRAPPA (5.4%) and higher for CG-SENSE (6.2%) and Tikhonov-regularized CG-SENSE (7.9%). CONCLUSION Multiband accelerated myocardial T1 mapping demonstrated the potential for single-breath-hold T1 quantification in 16 American Heart Association segments over three slices. A 1.2- to 1.4-fold higher in vivo spatial variability was observed, where GRAPPA-based reconstruction showed the highest homogeneity and the least interslice leakage. Magn Reson Med 78:462-471, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Sebastian Weingärtner
- Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
- Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
| | - Steen Moeller
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Sebastian Schmitter
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
- Medical Physics and Metrological Information Technology, Physikalisch-Technische Bundesanstalt, Berlin, Germany
| | - Edward Auerbach
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Peter Kellman
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | - Chetan Shenoy
- Cardiovascular Division, Department of Medicine, University of Minnesota, Minneapolis, MN, United States
| | - Mehmet Akçakaya
- Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
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Stoffers RH, Madden M, Shahid M, Contijoch F, Solomon J, Pilla JJ, Gorman JH, Gorman RC, Witschey WR. Assessment of myocardial injury after reperfused infarction by T1ρ cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2017; 19:17. [PMID: 28196494 PMCID: PMC5310026 DOI: 10.1186/s12968-017-0332-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 01/24/2017] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The evolution of T1ρ and of other endogenous contrast methods (T2, T1) in the first month after reperfused myocardial infarction (MI) is uncertain. We conducted a study of reperfused MI in pigs to serially monitor T1ρ, T2 and T1 relaxation, scar size and transmurality at 1 and 4 weeks post-MI. METHODS Ten Yorkshire swine underwent 90 min of occlusion of the circumflex artery and reperfusion. T1ρ, T2 and native T1 maps and late gadolinium enhanced (LGE) cardiovascular magnetic resonance (CMR) data were collected at 1 week (n = 10) and 4 weeks (n = 5). Semi-automatic FWHM (full width half maximum) thresholding was used to assess scar size and transmurality and compared to histology. Relaxation times and contrast-to-noise ratio were compared in healthy and remote myocardium at 1 and 4 weeks. Linear regression and Bland-Altman was performed to compare infarct size and transmurality. RESULTS Relaxation time differences between infarcted and remote myocardial tissue were ∆T1 (infarct-remote) = 421.3 ± 108.8 (1 week) and 480.0 ± 33.2 ms (4 week), ∆T1ρ = 68.1 ± 11.6 and 74.3 ± 14.2, and ∆T2 = 51.0 ± 10.1 and 59.2 ± 11.4 ms. Contrast-to-noise ratio was CNRT1 = 7.0 ± 3.5 (1 week) and 6.9 ± 2.4 (4 week), CNRT1ρ = 12.0 ± 6.2 and 12.3 ± 3.2, and CNRT2 = 8.0 ± 3.6 and 10.3 ± 5.8. Infarct size was not significantly different for T1ρ, T1 and T2 compared to LGE (p = 0.14) and significantly decreased from 1 to 4 weeks (p < 0.01). Individual infarct size changes were ∆T1ρ = -3.8%, ∆T1 = -3.5% and ∆LGE = -2.8% from 1 - 4 weeks, but there was no observed change in infarct size for T2 or histologically. CONCLUSIONS T1ρ was highly correlated with alterations left ventricle (LV) pathology at 1 and 4 weeks post-MI and therefore it may be a useful method endogenous contrast imaging of infarction.
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Affiliation(s)
- Rutger H. Stoffers
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA USA
| | - Marie Madden
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
| | - Mohammed Shahid
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
| | - Francisco Contijoch
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA USA
| | - Joseph Solomon
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
| | - James J. Pilla
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
| | - Joseph H. Gorman
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA USA
| | - Robert C. Gorman
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA USA
| | - Walter R.T. Witschey
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein 3400 Spruce Street, Philadelphia, PA USA 19104
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Early Changes of Irradiated Parotid Glands Evaluated by T1rho-Weighted Imaging. J Comput Assist Tomogr 2017; 41:472-476. [DOI: 10.1097/rct.0000000000000547] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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24
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Chen W. Artifacts correction for T1rho imaging with constant amplitude spin-lock. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 274:13-23. [PMID: 27842257 DOI: 10.1016/j.jmr.2016.11.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 10/16/2016] [Accepted: 11/04/2016] [Indexed: 06/06/2023]
Abstract
T1rho imaging with constant amplitude spin-lock is prone to artifacts in the presence of B1 RF and B0 field inhomogeneity. Despite significant technological progress, improvements on the robustness of constant amplitude spin-lock are necessary in order to use it for routine clinical practice. This work proposes methods to simultaneously correct for B1 RF and B0 field inhomogeneity in constant amplitude spin-lock. By setting the maximum B1 amplitude of the excitation adiabatic pulses equal to the expected constant amplitude spin-lock frequency, the spins become aligned along the effective field throughout the spin-lock process. This results in T1rho-weighted images free of artifacts, despite the spatial variation of the effective field caused by B1 RF and B0 field inhomogeneity. When the pulse is long, the relaxation effect during the adiabatic half passage may result in a non-negligible error in the mono-exponential relaxation model. A two-acquisition approach is presented to solve this issue. Simulation, phantom, and in-vivo scans demonstrate the proposed methods achieve superior image quality compared to existing methods, and that the two-acquisition method is effective in resolving the relaxation effect during the adiabatic half passage.
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Affiliation(s)
- Weitian Chen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong Special Administrative Region.
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Peng XG, Wang Y, Zhang S, Bai Y, Mao H, Teng GJ, Ju S. Noninvasive assessment of age, gender, and exercise effects on skeletal muscle: Initial experience with T 1 ρ MRI of calf muscle. J Magn Reson Imaging 2016; 46:61-70. [PMID: 27862560 DOI: 10.1002/jmri.25546] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/25/2016] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To prospectively investigate age- and gender-related changes in the fast-twitch (tibialis anterior, TA) and slow-twitch (soleus, SOL) skeletal muscle of healthy rats and volunteers and to compare the exercise-related difference in health volunteers with T1 ρ magnetic resonance imaging (MRI). MATERIALS AND METHODS In all, 18 rats and 70 humans were involved in this study. For the animal study, T1 ρ relaxation times were measured in the TA and SOL rat muscle with a 3.0T MRI scanner and compared to histological data. For the human study, three groups (young, middle-aged, and elderly) of volunteers underwent T1 ρ MRI scans (3.0T) of their calves. To further differentiate the human scans, 18 volunteers were recruited, half of them (n = 9) routinely trained with high-intensity sports, while the other half (n = 9) with no physical training. Statistical analysis was performed via paired t-test, independent-sample t-test, and analysis of variance (ANOVA). Correlations between T1 ρ and age/gender/physical endurance were calculated. RESULTS The average T1 ρ relaxation times of the TA and SOL of female rats were higher than that of male rats (P < 0.001). The T1 ρ relaxation time of TA was significantly lower compared to SOL (P < 0.001). A significant linear correlation was observed between T1 ρ and the type I slow-twitch fiber proportion (%) in SOL (R2 = 0.837, P < 0.001). Similarly, in human studies the average T1 ρ relaxation times of TA were significantly lower than SOL for all age groups (P < 0.001). The higher T1 ρ relaxation times of TA and SOL in the elderly volunteers (P < 0.001) and in the females (P < 0.05) indicated significant age- and gender-dependent differences. In high-intensity sports groups, the higher T1 ρ in SOL (P < 0.01) and lower in TA (P < 0.05) were observed compared with the control group. CONCLUSION This study demonstrated that T1 ρ MRI can be used to display the differences in fast- and slow-twitch skeletal muscle as well as potentially age-, gender-, and exercise-related differences. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:61-70.
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Affiliation(s)
- Xin-Gui Peng
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
| | - Yuancheng Wang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
| | - Shijun Zhang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
| | - Yingying Bai
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
| | - Hui Mao
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Gao-Jun Teng
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
| | - Shenghong Ju
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, P.R. China
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26
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Mitrea BG, Krafft AJ, Song R, Loeffler RB, Hillenbrand CM. Paired self-compensated spin-lock preparation for improved T1ρ quantification. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 268:49-57. [PMID: 27161095 DOI: 10.1016/j.jmr.2016.04.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 06/05/2023]
Abstract
PURPOSE Spin-lock (SL) imaging allows quantification of the spin-lattice relaxation time in the rotating frame (T1ρ). B0 and B1 inhomogeneities impact T1ρ quantification because the preparatory block in SL imaging is sensitive to the field heterogeneities. Here, a modified preparatory block (PSC-SL) is proposed that attempts to alleviate SL sensitivity to field inhomogeneities in scenarios where existing approaches fail, i.e. high SL frequencies. METHODS Computer simulations, phantom and in vivo experiments were used to determine the effect of field inhomogeneities on T1ρ quantification. Existing SL preparations were compared with PSC-SL in different conditions to assess the advantages and disadvantages of each method. RESULTS Phantom experiments and computer modeling demonstrate that PSC-SL provides superior T1ρ quantification at high SL frequencies in situations where the existing SL preparation methods fail. This result has been confirmed in pre-clinical neuro and body imaging at 7T. CONCLUSION PSC-SL complements existing methods by increasing the accuracy of T1ρ quantification at high spin-lock frequencies when large field inhomogeneities are present. A-priory information about the experimental conditions such, as field distribution and spinlock frequency are useful for selecting an appropriate spin-lock preparation for specific applications.
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Affiliation(s)
- Bogdan G Mitrea
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Axel J Krafft
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ruitian Song
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ralf B Loeffler
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Claudia M Hillenbrand
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA.
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van Oorschot JWM, Güçlü F, de Jong S, Chamuleau SAJ, Luijten PR, Leiner T, Zwanenburg JJM. Endogenous assessment of diffuse myocardial fibrosis in patients with T 1ρ -mapping. J Magn Reson Imaging 2016; 45:132-138. [PMID: 27309545 DOI: 10.1002/jmri.25340] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 05/26/2016] [Indexed: 01/31/2023] Open
Abstract
PURPOSE Recently, it was shown that a significantly higher T1ρ is found in compact myocardial fibrosis after chronic myocardial infarction. In this study, we investigated the feasibility of native T1ρ -mapping for the detection of diffuse myocardial fibrosis in patients with dilated cardiomyopathy (DCM). MATERIALS AND METHODS T1ρ -mapping was performed on three explanted hearts from DCM patients at 3 Tesla (T). Histological fibrosis quantification was performed, and compared with the T1ρ -relaxation times in the heart. Furthermore, twenty DCM patients underwent an MRI at 1.5T. Native T1ρ -maps, native T1 -maps, and extracellular volume (ECV)-maps were acquired. Additionally, eight healthy volunteers were scanned for reference values. RESULTS A significant correlation (Pearson r = 0.49; P = 0.005) was found between ex vivo T1ρ -values and fibrosis fraction from histology. Additionally, a significantly higher T1ρ -relaxation time (55.2 ± 2.7 ms) was found in DCM patients compared with healthy control subjects (51.5 ± 1.2 ms) (P = 0.0024). The relation between in vivo T1ρ -values and ECV-values was significant (Pearson r = 0.66). No significant relation was found between native T1 - and ECV-values in this study (P = 0.89). CONCLUSION This study showed proof of principle for the endogenous detection of diffuse myocardial fibrosis with T1ρ -MRI. Ex vivo and in vivo experiments showed promising results that T1ρ -MRI can be used to measure the extent of diffuse myocardial fibrosis in the myocardium. LEVEL OF EVIDENCE 2 J. Magn. Reson. Imaging 2017;45:132-138.
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Affiliation(s)
- Joep W M van Oorschot
- Philips Healthcare, Best, The Netherlands.,Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Fatih Güçlü
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Sanne de Jong
- Department of Medical Physiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Steven A J Chamuleau
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter R Luijten
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Tim Leiner
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jaco J M Zwanenburg
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
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Zhang J, Nissi MJ, Idiyatullin D, Michaeli S, Garwood M, Ellermann J. Capturing fast relaxing spins with SWIFT adiabatic rotating frame spin-lattice relaxation (T1ρ) mapping. NMR IN BIOMEDICINE 2016; 29:420-30. [PMID: 26811973 PMCID: PMC4805510 DOI: 10.1002/nbm.3474] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 11/20/2015] [Accepted: 11/28/2015] [Indexed: 05/18/2023]
Abstract
Rotating frame spin-lattice relaxation, with the characteristic time constant T1ρ, provides a means to access motion-restricted (slow) spin dynamics in MRI. As a result of their restricted motion, these spins are sometimes characterized by a short transverse relaxation time constant T2 and thus can be difficult to detect directly with conventional image acquisition techniques. Here, we introduce an approach for three-dimensional adiabatic T1ρ mapping based on a magnetization-prepared sweep imaging with Fourier transformation (MP-SWIFT) sequence, which captures signal from almost all water spin populations, including the extremely fast relaxing pool. A semi-analytical procedure for T1ρ mapping is described. Experiments on phantoms and musculoskeletal tissue specimens (tendon, articular and epiphyseal cartilages) were performed at 9.4 T for both the MP-SWIFT and fast spin echo (FSE) read outs. In the phantom with liquids having fast molecular tumbling and a single-valued T1ρ time constant, the measured T1ρ values obtained with MP-SWIFT and FSE were similar. Conversely, in normal musculoskeletal tissues, T1ρ values measured with MP-SWIFT were much shorter than the values obtained with FSE. Studies of biological tissue specimens demonstrated that T1ρ-weighted SWIFT provides higher contrast between normal and diseased tissues relative to conventional acquisitions. Adiabatic T1ρ mapping with SWIFT readout captures contributions from the otherwise undetected fast relaxing spins, allowing more informative T1ρ measurements of normal and diseased states.
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Affiliation(s)
- J Zhang
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - M J Nissi
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
- Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - D Idiyatullin
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - S Michaeli
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - M Garwood
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - J Ellermann
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, USA
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Berisha S, Han J, Shahid M, Han Y, Witschey WRT. Measurement of Myocardial T1ρ with a Motion Corrected, Parametric Mapping Sequence in Humans. PLoS One 2016; 11:e0151144. [PMID: 27003184 PMCID: PMC4803208 DOI: 10.1371/journal.pone.0151144] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/23/2016] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To develop a robust T1ρ magnetic resonance imaging (MRI) sequence for assessment of myocardial disease in humans. MATERIALS AND METHODS We developed a breath-held T1ρ mapping method using a single-shot, T1ρ-prepared balanced steady-state free-precession (bSSFP) sequence. The magnetization trajectory was simulated to identify sources of T1ρ error. To limit motion artifacts, an optical flow-based image registration method was used to align T1ρ images. The reproducibility and accuracy of these methods was assessed in phantoms and 10 healthy subjects. Results are shown in 1 patient with pre-ventricular contractions (PVCs), 1 patient with chronic myocardial infarction (MI) and 2 patients with hypertrophic cardiomyopathy (HCM). RESULTS In phantoms, the mean bias was 1.0 ± 2.7 msec (100 msec phantom) and 0.9 ± 0.9 msec (60 msec phantom) at 60 bpm and 2.2 ± 3.2 msec (100 msec) and 1.4 ± 0.9 msec (60 msec) at 80 bpm. The coefficient of variation (COV) was 2.2 (100 msec) and 1.3 (60 msec) at 60 bpm and 2.6 (100 msec) and 1.4 (60 msec) at 80 bpm. Motion correction improved the alignment of T1ρ images in subjects, as determined by the increase in Dice Score Coefficient (DSC) from 0.76 to 0.88. T1ρ reproducibility was high (COV < 0.05, intra-class correlation coefficient (ICC) = 0.85-0.97). Mean myocardial T1ρ value in healthy subjects was 63.5 ± 4.6 msec. There was good correspondence between late-gadolinium enhanced (LGE) MRI and increased T1ρ relaxation times in patients. CONCLUSION Single-shot, motion corrected, spin echo, spin lock MRI permits 2D T1ρ mapping in a breath-hold with good accuracy and precision.
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Affiliation(s)
- Sebastian Berisha
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Joyce Han
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Mohammed Shahid
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Yuchi Han
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Walter R. T. Witschey
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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Wang L, Yuan J, Zhang SJ, Gao M, Wang YC, Wang YX, Ju S. MyocardialT1rho mapping of patients with end-stage renal disease and its comparison withT1mapping andT2mapping: A feasibility and reproducibility study. J Magn Reson Imaging 2016; 44:723-31. [PMID: 26889749 DOI: 10.1002/jmri.25188] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 01/22/2016] [Indexed: 02/02/2023] Open
Affiliation(s)
- Lin Wang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital; Medical School of Southeast University; Nanjing China
| | - Jing Yuan
- Medical Physics and Research Department; Hong Kong Sanatorium & Hospital; Happy Valley Hong Kong SAR China
| | - Shi-Jun Zhang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital; Medical School of Southeast University; Nanjing China
| | - Min Gao
- Department of Nephology, Zhongda Hospital; Medical School of Southeast University; Nanjing China
| | - Yuan-Cheng Wang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital; Medical School of Southeast University; Nanjing China
| | - Yi-Xiang Wang
- Department of Imaging and Interventional Radiology, Prince of Wales Hospital; the Chinese University of Hong Kong; Shatin Hong Kong SAR China
| | - Shenghong Ju
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital; Medical School of Southeast University; Nanjing China
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Abstract
The spin-lattice relaxation time constant in rotating frame (T1rho) is useful for assessment of the properties of macromolecular environment inside tissue. Quantification of T1rho is found promising in various clinical applications. However, T1rho imaging is prone to image artifacts and quantification errors, which remains one of the greatest challenges to adopt this technique in routine clinical practice. The conventional continuous wave spin-lock is susceptible to B1 radiofrequency (RF) and B0 field inhomogeneity, which appears as banding artifacts in acquired images. A number of methods have been reported to modify T1rho prep RF pulse cluster to mitigate this effect. Adiabatic RF pulse can also be used for spin-lock with insensitivity to both B1 RF and B0 field inhomogeneity. Another source of quantification error in T1rho imaging is signal evolution during imaging data acquisition. Care is needed to affirm such error does not take place when specific pulse sequence is used for imaging data acquisition. Another source of T1rho quantification error is insufficient signal-to-noise ratio (SNR), which is common among various quantitative imaging approaches. Measurement of T1rho within an ROI can mitigate this issue, but at the cost of reduced resolution. Noise-corrected methods are reported to address this issue in pixel-wise quantification. For certain tissue type, T1rho quantification can be confounded by magic angle effect and the presence of multiple tissue components. Review of these confounding factors from inherent tissue properties is not included in this article.
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Affiliation(s)
- Weitian Chen
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, China
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Bakermans AJ, Abdurrachim D, Moonen RPM, Motaal AG, Prompers JJ, Strijkers GJ, Vandoorne K, Nicolay K. Small animal cardiovascular MR imaging and spectroscopy. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 88-89:1-47. [PMID: 26282195 DOI: 10.1016/j.pnmrs.2015.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
The use of MR imaging and spectroscopy for studying cardiovascular disease processes in small animals has increased tremendously over the past decade. This is the result of the remarkable advances in MR technologies and the increased availability of genetically modified mice. MR techniques provide a window on the entire timeline of cardiovascular disease development, ranging from subtle early changes in myocardial metabolism that often mark disease onset to severe myocardial dysfunction associated with end-stage heart failure. MR imaging and spectroscopy techniques play an important role in basic cardiovascular research and in cardiovascular disease diagnosis and therapy follow-up. This is due to the broad range of functional, structural and metabolic parameters that can be quantified by MR under in vivo conditions non-invasively. This review describes the spectrum of MR techniques that are employed in small animal cardiovascular disease research and how the technological challenges resulting from the small dimensions of heart and blood vessels as well as high heart and respiratory rates, particularly in mice, are tackled.
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Affiliation(s)
- Adrianus J Bakermans
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Desiree Abdurrachim
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Rik P M Moonen
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Abdallah G Motaal
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeanine J Prompers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Gustav J Strijkers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Katrien Vandoorne
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Klaas Nicolay
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
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van Oorschot JWM, El Aidi H, Jansen of Lorkeers SJ, Gho JMIH, Froeling M, Visser F, Chamuleau SAJ, Doevendans PA, Luijten PR, Leiner T, Zwanenburg JJM. Endogenous assessment of chronic myocardial infarction with T(1ρ)-mapping in patients. J Cardiovasc Magn Reson 2014; 16:104. [PMID: 25526973 PMCID: PMC4272542 DOI: 10.1186/s12968-014-0104-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 12/01/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Detection of cardiac fibrosis based on endogenous magnetic resonance (MR) characteristics of the myocardium would yield a measurement that can provide quantitative information, is independent of contrast agent concentration, renal function and timing. In ex vivo myocardial infarction (MI) tissue, it has been shown that a significantly higher T(1ρ) is found in the MI region, and studies in animal models of chronic MI showed the first in vivo evidence for the ability to detect myocardial fibrosis with native T(1ρ)-mapping. In this study we aimed to translate and validate T(1ρ)-mapping for endogenous detection of chronic MI in patients. METHODS We first performed a study in a porcine animal model of chronic MI to validate the implementation of T(1ρ)-mapping on a clinical cardiovascular MR scanner and studied the correlation with histology. Subsequently a clinical protocol was developed, to assess the feasibility of scar tissue detection with native T(1ρ)-mapping in patients (n = 21) with chronic MI, and correlated with gold standard late gadolinium enhancement (LGE) CMR. Four T1ρ-weighted images were acquired using a spin-lock preparation pulse with varying duration (0, 13, 27, 45 ms) and an amplitude of 750 Hz, and a T(1ρ)-map was calculated. The resulting T(1ρ)-maps and LGE images were scored qualitatively for the presence and extent of myocardial scarring using the 17-segment AHA model. RESULTS In the animal model (n = 9) a significantly higher T(1ρ) relaxation time was found in the infarct region (61 ± 11 ms), compared to healthy remote myocardium (36 ± 4 ms) . In patients a higher T(1ρ) relaxation time (79 ± 11 ms) was found in the infarct region than in remote myocardium (54 ± 6 ms). Overlap in the scoring of scar tissue on LGE images and T(1ρ)-maps was 74%. CONCLUSION We have shown the feasibility of native T(1ρ)-mapping for detection of infarct area in patients with a chronic myocardial infarction. In the near future, improvements on the T(1ρ)-mapping sequence could provide a higher sensitivity and specificity. This endogenous method could be an alternative for LGE imaging, and provide additional quantitative information on myocardial tissue characteristics.
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Affiliation(s)
- Joep WM van Oorschot
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
| | - Hamza El Aidi
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
- />Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Johannes MIH Gho
- />Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Martijn Froeling
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
| | | | - Steven AJ Chamuleau
- />Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Pieter A Doevendans
- />Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter R Luijten
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
| | - Tim Leiner
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
| | - Jaco JM Zwanenburg
- />Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100 3582 CX, Utrecht, The Netherlands
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van Oorschot JW, Gho JM, van Hout GP, Froeling M, Jansen of Lorkeers SJ, Hoefer IE, Doevendans PA, Luijten PR, Chamuleau SA, Zwanenburg JJ. Endogenous contrast MRI of cardiac fibrosis: Beyond late gadolinium enhancement. J Magn Reson Imaging 2014; 41:1181-9. [DOI: 10.1002/jmri.24715] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 07/14/2014] [Accepted: 07/15/2014] [Indexed: 12/27/2022] Open
Affiliation(s)
| | - Johannes M.I.H. Gho
- Department of Cardiology; University Medical Center Utrecht; Utrecht The Netherlands
| | | | - Martijn Froeling
- Department of Radiology; University Medical Center Utrecht; Utrecht The Netherlands
| | | | - Imo E. Hoefer
- Department of Cardiology; University Medical Center Utrecht; Utrecht The Netherlands
| | - Pieter A. Doevendans
- Department of Cardiology; University Medical Center Utrecht; Utrecht The Netherlands
| | - Peter R. Luijten
- Department of Radiology; University Medical Center Utrecht; Utrecht The Netherlands
| | - Steven A.J. Chamuleau
- Department of Cardiology; University Medical Center Utrecht; Utrecht The Netherlands
| | - Jaco J.M. Zwanenburg
- Department of Radiology; University Medical Center Utrecht; Utrecht The Netherlands
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Wang L, Regatte RR. T₁ρ MRI of human musculoskeletal system. J Magn Reson Imaging 2014; 41:586-600. [PMID: 24935818 DOI: 10.1002/jmri.24677] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/03/2014] [Indexed: 12/21/2022] Open
Abstract
Magnetic resonance imaging (MRI) offers the direct visualization of the human musculoskeletal (MSK) system, especially all diarthrodial tissues including cartilage, bone, menisci, ligaments, tendon, hip, synovium, etc. Conventional MRI techniques based on T1 - and T2 -weighted, proton density (PD) contrast are inconclusive in quantifying early biochemically degenerative changes in MSK system in general and articular cartilage in particular. In recent years, quantitative MR parameter mapping techniques have been used to quantify the biochemical changes in articular cartilage, with a special emphasis on evaluating joint injury, cartilage degeneration, and soft tissue repair. In this article we focus on cartilage biochemical composition, basic principles of T1ρ MRI, implementation of T1ρ pulse sequences, biochemical validation, and summarize the potential applications of the T1ρ MRI technique in MSK diseases including osteoarthritis (OA), anterior cruciate ligament (ACL) injury, and knee joint repair. Finally, we also review the potential advantages, challenges, and future prospects of T1ρ MRI for widespread clinical translation.
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Affiliation(s)
- Ligong Wang
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Medical College of Soochow University, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu, China
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36
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Kali A, Cokic I, Tang RLQ, Yang HJ, Sharif B, Marbán E, Li D, Berman DS, Dharmakumar R. Determination of location, size, and transmurality of chronic myocardial infarction without exogenous contrast media by using cardiac magnetic resonance imaging at 3 T. Circ Cardiovasc Imaging 2014; 7:471-81. [PMID: 24682268 DOI: 10.1161/circimaging.113.001541] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Late-gadolinium-enhanced (LGE) cardiac MRI (CMR) is a powerful method for characterizing myocardial infarction (MI), but the requisite gadolinium infusion is estimated to be contraindicated in ≈20% of patients with MI because of end-stage chronic kidney disease. The purpose of this study is to investigate whether T1 CMR obtained without contrast agents at 3 T could be an alternative to LGE CMR for characterizing chronic MIs using a canine model of MI. METHODS AND RESULTS Canines (n=29) underwent CMR at 7 days (acute MI [AMI]) and 4 months (chronic MI [CMI]) after MI. Infarct location, size, and transmurality measured by using native T1 maps and LGE images at 1.5 T and 3 T were compared. Resolution of edema between AMI and CMI was examined with T2 maps. T1 maps overestimated infarct size and transmurality relative to LGE images in AMI (P=0.016 and P=0.007, respectively), which was not observed in CMI (P=0.49 and P=0.81, respectively) at 3 T. T1 maps underestimated infarct size and transmurality relative to LGE images in AMI and CMI (P<0.001) at 1.5 T. Relative to the remote territories, T1 of the infarcted myocardium was increased in CMI and AMI (P<0.05), and T2 of the infarcted myocardium was increased in AMI (P<0.001) but not in CMI (P>0.20) at both field strengths. Histology showed extensive replacement fibrosis within the CMI territories. CMI detection sensitivity and specificity of T1 CMR at 3 T were 95% and 97%, respectively. CONCLUSIONS Native T1 maps at 3 T can determine the location, size, and transmurality of CMI with high diagnostic accuracy. Patient studies are necessary for clinical translation.
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Affiliation(s)
- Avinash Kali
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Ivan Cokic
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Richard L Q Tang
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Hsin-Jung Yang
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Behzad Sharif
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Eduardo Marbán
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Debiao Li
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Daniel S Berman
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.)
| | - Rohan Dharmakumar
- From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
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Han Y, Liimatainen T, Gorman RC, Witschey WRT. Assessing Myocardial Disease Using T 1ρ MRI. CURRENT CARDIOVASCULAR IMAGING REPORTS 2014; 7:9248. [PMID: 24688628 PMCID: PMC3968806 DOI: 10.1007/s12410-013-9248-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
There is great interest to use magnetic resonance imaging (MRI) for non-invasive assessment of myocardial disease in ischemic and non-ischemic cardiomyopathies. Recently, there has been a renewed interest to use a magnetic resonance imaging (MRI) technique utilizing spin locking radiofrequency (RF) pulses, called T1ρ MRI. The spin locking RF pulse creates sensitivity to some mechanisms of nuclear relaxation such as 1H exchange between water and amide, amine and hydroxyl functional groups in molecules; consequently, there is the potential to non-invasively, and without exogenous contrast agents, obtain important molecular information from diseased myocardial tissue. The purpose of this article is to review and critically examine the recent published literature in the field related to T1ρ MRI of myocardial disease.
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Affiliation(s)
- Yuchi Han
- Cardiovascular Division, Department of Medicine, Perelman School of Medicine, Hospital of the University of Pennsylvania, 9022 Gates, 3400 Spruce Street, Philadelphia, PA, USA
| | - Timo Liimatainen
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Robert C. Gorman
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg 421, 7th floor, Rm 103, Philadelphia, PA 19104, USA
| | - Walter R. T. Witschey
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg 421, 7th floor, Rm 103, Philadelphia, PA 19104, USA
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Musthafa HSN, Dragneva G, Lottonen L, Merentie M, Petrov L, Heikura T, Ylä-Herttuala E, Ylä-Herttuala S, Gröhn O, Liimatainen T. Longitudinal rotating frame relaxation time measurements in infarcted mouse myocardium in vivo. Magn Reson Med 2012; 69:1389-95. [DOI: 10.1002/mrm.24382] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 05/02/2012] [Accepted: 05/28/2012] [Indexed: 12/21/2022]
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Witschey WRT, Zsido GA, Koomalsingh K, Kondo N, Minakawa M, Shuto T, McGarvey JR, Levack MM, Contijoch F, Pilla JJ, Gorman JH, Gorman RC. In vivo chronic myocardial infarction characterization by spin locked cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2012; 14:37. [PMID: 22704222 PMCID: PMC3461454 DOI: 10.1186/1532-429x-14-37] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/15/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Late gadolinium enhanced (LGE) cardiovascular magnetic resonance (CMR) is frequently used to evaluate myocardial viability, estimate total infarct size and transmurality, but is not always straightforward is and contraindicated in patients with renal failure because of the risk of nephrogenic systemic fibrosis. T2- and T1-weighted CMR alone is however relatively insensitive to chronic myocardial infarction (MI) in the absence of a contrast agent. The objective of this manuscript is to explore T1ρ-weighted rotating frame CMR techniques for infarct characterization without contrast agents. We hypothesize that T1ρ CMR accurately measures infarct size in chronic MI on account of a large change in T1ρ relaxation time between scar and myocardium. METHODS 7Yorkshire swine underwent CMR at 8 weeks post-surgical induction of apical or posterolateral myocardial infarction. Late gadolinium enhanced and T1ρ CMR were performed at high resolution to visualize MI. T1ρ-weighted imaging was performed with a B₁ = 500 Hz spin lock pulse on a 3 T clinical MR scanner. Following sacrifice, the heart was excised and infarct size was calculated by optical planimetry. Infarct size was calculated for all three methods (LGE, T1ρ and planimetry) and statistical analysis was performed. T1ρ relaxation time maps were computed from multiple T1ρ-weighted images at varying spin lock duration. RESULTS Mean infarct contrast-to-noise ratio (CNR) in LGE and T1ρ CMR was 2.8 ± 0.1 and 2.7 ± 0.1. The variation in signal intensity of tissues was found to be, in order of decreasing signal intensity, LV blood, fat and edema, infarct and healthy myocardium. Infarct size measured by T1ρ CMR (21.1% ± 1.4%) was not significantly different from LGE CMR (22.2% ± 1.5%) or planimetry (21.1% ± 2.7%; p < 0.05).T1ρ relaxation times were T1ρinfarct = 91.7 ms in the infarct and T1ρremote = 47.2 ms in the remote myocardium. CONCLUSIONS T1ρ-weighted imaging using long spin locking pulses enables high discrimination between infarct and myocardium. T1ρ CMR may be useful to visualizing MI without the need for exogenous contrast agents for a wide range of clinical cardiac applications such as to distinguish edema and scar tissue and tissue characterization of myocarditis and ventricular fibrosis.
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Affiliation(s)
- Walter RT Witschey
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
- Department of Radiology, University of Pennsylvania, 500 S Ridgeway Ave, Glenolden, PA 19036, USA
| | - Gerald A Zsido
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin Koomalsingh
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Norihiro Kondo
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Masahito Minakawa
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Takashi Shuto
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Jeremy R McGarvey
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Melissa M Levack
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Francisco Contijoch
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - James J Pilla
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
- Department of Radiology, University of Pennsylvania, 500 S Ridgeway Ave, Glenolden, PA 19036, USA
| | - Joseph H Gorman
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert C Gorman
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
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Richardson OC, Scott MLJ, Tanner SF, Waterton JC, Buckley DL. Overcoming the low relaxivity of gadofosveset at high field with spin locking. Magn Reson Med 2011; 68:1234-8. [PMID: 22161901 PMCID: PMC3666098 DOI: 10.1002/mrm.23316] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 11/10/2011] [Accepted: 11/12/2011] [Indexed: 01/13/2023]
Abstract
The contrast agent gadofosveset, which binds reversibly to serum albumin, has a high longitudinal relaxivity at lower magnetic fields (≤3.0 T) but a much lower relaxivity at high fields. Spin locking is sensitive to macromolecular content; it is hypothesized that combining this technique with the albumin-binding properties of gadofosveset may enable increased relaxivity at high fields. In vitro measurements at 4.7 T found significantly higher spin-lock relaxation rates, R1ρ (1/T1ρ), when gadofosveset was serum albumin-bound than when unbound. R1ρ values for a nonbinding contrast agent (gadopentetate dimeglumine) in serum albumin were similar to those for unbound gadofosveset. R2 (1/T2) values were also significantly higher at 4.7 T for serum albumin-bound gadofosveset than for unbound. Spin locking at high field generates significantly higher relaxation rates for gadofosveset than conventional contrast agents and may provide a method for differentiating free and bound molecules at these field strengths.
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Affiliation(s)
- O C Richardson
- Division of Medical Physics, University of Leeds, Leeds, UK
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Ferrari VA, Witschey WR, Zhou R. Cardiac Magnetic Resonance Assessment of Myocardial Fibrosis. Circ Cardiovasc Imaging 2011; 4:604-6. [DOI: 10.1161/circimaging.111.969204] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Victor A. Ferrari
- From the Cardiovascular Magnetic Resonance Program, Penn Cardiovascular Institute, and the Noninvasive Imaging Laboratory, Hospital of the University of Pennsylvania, University of Pennsylvania Medical Center, Philadelphia, PA (V.A.F.); Center for Magnetic Resonance and Optical Imaging, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, PA (W.R.T.W.); and Molecular Imaging Laboratories, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia,
| | - Walter R.T. Witschey
- From the Cardiovascular Magnetic Resonance Program, Penn Cardiovascular Institute, and the Noninvasive Imaging Laboratory, Hospital of the University of Pennsylvania, University of Pennsylvania Medical Center, Philadelphia, PA (V.A.F.); Center for Magnetic Resonance and Optical Imaging, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, PA (W.R.T.W.); and Molecular Imaging Laboratories, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia,
| | - Rong Zhou
- From the Cardiovascular Magnetic Resonance Program, Penn Cardiovascular Institute, and the Noninvasive Imaging Laboratory, Hospital of the University of Pennsylvania, University of Pennsylvania Medical Center, Philadelphia, PA (V.A.F.); Center for Magnetic Resonance and Optical Imaging, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, PA (W.R.T.W.); and Molecular Imaging Laboratories, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia,
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Witschey WRT, Pilla JJ, Ferrari G, Koomalsingh K, Haris M, Hinmon R, Zsido G, Gorman JH, Gorman RC, Reddy R. Rotating frame spin lattice relaxation in a swine model of chronic, left ventricular myocardial infarction. Magn Reson Med 2011; 64:1453-60. [PMID: 20677236 DOI: 10.1002/mrm.22543] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
T1ρ relaxation times were quantified in a swine model of chronic, left ventricular myocardial infarction. It was found that there were low frequency relaxation mechanisms that suppress endogenous contrast at low spin-lock amplitudes and in T2-weighted images. A moderate amplitude spin-locking pulse could overcome these relaxation mechanisms. Relaxation dispersion data were measured over a range of RF field amplitudes, and a model was formulated to include dipole-dipole relaxation modulated by molecular rotation and an apparent exchange mechanism. These techniques may find some use in the clinic for the observation of chronic, left ventricular cardiac remodeling.
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Affiliation(s)
- Walter R T Witschey
- Department of Radiology, Medical Physics, University Hospital Freiburg, Freiburg im Breisgau, Germany.
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Carbone I, Francone M, Chimenti C, Galea N, Russo M, Frustaci A. Images in cardiovascular medicine: Right ventricular late enhancement as a magnetic resonance marker of glycogen storage disease. Circulation 2010; 122:189-90. [PMID: 20625144 DOI: 10.1161/circulationaha.109.933911] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Iacopo Carbone
- Departments of Radiologic Science, La Sapienza University, Viale del Policlinico 155, 00100 Rome, Italy
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Peters DC, Wylie JV, Hauser TH, Kissinger KV, Botnar RM, Essebag V, Josephson ME, Manning WJ. Detection of Pulmonary Vein and Left Atrial Scar after Catheter Ablation with Three-dimensional Navigator-gated Delayed Enhancement MR Imaging: Initial Experience1. Radiology 2007; 243:690-5. [PMID: 17517928 DOI: 10.1148/radiol.2433060417] [Citation(s) in RCA: 260] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE To prospectively evaluate whether scar caused by radiofrequency (RF) ablation of the left atrium (LA) in patients with atrial fibrillation can be depicted with high-spatial-resolution delayed enhancement magnetic resonance (MR) imaging. MATERIALS AND METHODS All 23 subjects (16 men, seven women; mean age, 54 years +/- 13 [standard deviation]) provided written informed consent; the study was approved by the local institutional review board and was HIPAA compliant. A high-spatial-resolution free-breathing delayed enhancement MR imaging method was developed to detect scar (ie, ablated tissue) in the LA and pulmonary veins (PVs). The LA in 15 patients before ablation and in 18 patients at least 30 days after ablation was examined. A reader with 4 years of experience assessed presence of delayed enhancement on images and circumferential completeness. Signal-to-noise and contrast-to-noise ratios were measured and compared with an unpaired t test. The relationship between measurements of enhancement thickness at the interatrial septum and the number of days after ablation was investigated. RESULTS No subject demonstrated preablation delayed enhancement of the atrial or PV wall, whereas postablation delayed enhancement was identified in all (100%). In patients after ablation, a partial to completely circumferential delayed enhancement pattern could be identified for the left inferior PV that encompassed 88% +/- 11 of the circumference, but only 62% of patients demonstrated more than 90% circumferential delayed enhancement. The signal-to-noise ratio of blood was 12, and the signal-to-noise ratios of the pre- and postablation left atrial wall were 15 and 22, respectively (P<.05). A relationship between delayed enhancement wall thickness and the inverse of the time interval from ablation was identified (P<.05). CONCLUSION High-spatial-resolution delayed enhancement MR imaging allows noninvasive identification of scar induced by RF ablation following isolation therapy of the PV.
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Affiliation(s)
- Dana C Peters
- Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, RW 453, Boston, MA 02215, USA.
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Huber S, Muthupillai R, Lambert B, Pereyra M, Napoli A, Flamm SD. Tissue characterization of myocardial infarction using T1rho: influence of contrast dose and time of imaging after contrast administration. J Magn Reson Imaging 2007; 24:1040-6. [PMID: 16972231 DOI: 10.1002/jmri.20720] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To determine whether contrast between acutely infarcted and normal myocardia in T1-rho-weighted cine TFE (T1rho-TFE) and delayed-enhancement (DE) images (measured using a metric percent enhancement (PE)) varied with the dose or time of imaging after contrast administration. MATERIALS AND METHODS Eighteen patients with acute myocardial infarction (AMI) were randomly divided into three groups according to the dose of gadoversetamide (0.1, 0.2, or 0.3 mmol/kg) administered. After contrast administration, T1rho-TFE images were acquired at five and 40 minutes, and DE images were acquired at 10 and 30 minutes. RESULTS For T1rho-TFE imaging the PE values at 40 minutes were 70+/-14, 98+/-14, and 105+/-41 at 0.1, 0.2, and 0.3 mmol/kg dose levels, which were significantly greater than the corresponding PEs at five minutes after contrast administration (44+/-12, 71+/-14, and 36+/-13). For DE and T1rho-TFE imaging the dose of contrast agent did not significantly affect the PE. However, with DE the PE tended to increase with the dose. At all dose levels, irreversible injury was more conspicuous in T1rho-TFE images acquired at 40 minutes than at five minutes after contrast. CONCLUSION In T1rho-TFE, acute infarction was more conspicuous in images acquired at a later time point, and the PE did not vary with the contrast dose.
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Affiliation(s)
- Steffen Huber
- Department of Radiology, St. Luke's Episcopal Hospital/Texas Heart Institute, and Baylor College of Medicine, Houston, Texas 77030, USA
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Raff GL, O'Neill WW, Gentry RE, Dulli A, Bis KG, Shetty AN, Goldstein JA. Microvascular Obstruction and Myocardial Function after Acute Myocardial Infarction: Assessment by Using Contrast-enhanced Cine MR Imaging. Radiology 2006; 240:529-36. [PMID: 16864676 DOI: 10.1148/radiol.2402050369] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
UNLABELLED This study was approved by the Human Investigation Committee of William Beaumont Hospital, and all patients gave informed consent. The purpose of this study was to prospectively compare contrast material-enhanced cine magnetic resonance (MR) imaging with more-standard MR imaging for the evaluation of microvascular obstruction and myocardial function in 80 patients (56 men, 24 women; mean age, 57 years; range, 29-80 years) with acute myocardial infarction after reperfusion therapy. Findings at contrast-enhanced cine MR imaging agreed with the global and transmural extent of microvascular obstruction at first-pass perfusion (intraclass correlation coefficient [IC] of 0.96 [P < .001] and 0.88 [P < .001], respectively) and inversion-recovery gradient-echo (IC of 0.90 [P < .001] and 0.93 [P < .001], respectively) MR imaging. There was no significant difference between myocardial function parameters before and after contrast material enhancement. Contrast-enhanced cine MR imaging reduced imaging time by 34% (11 of 32 minutes) and improved spatial resolution. SUPPLEMENTAL MATERIAL radiology.rsnajnls.org/cgi/content/full/240/2/529/DC1
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Affiliation(s)
- Gilbert L Raff
- Cardiology Division, Department of Internal Medicine, William Beaumont Hospital, 3601 W 13 Mile Rd, Royal Oak, MI 48073-6769, USA.
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Koskinen SK, Niemi PT, Kajander SA, Komu MES. T1ρ Dispersion profile of rat tissues in vitro at very low locking fields. Magn Reson Imaging 2006; 24:295-9. [PMID: 16563959 DOI: 10.1016/j.mri.2005.04.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2005] [Accepted: 12/11/2005] [Indexed: 10/25/2022]
Abstract
The purpose of this study was to show the T(1rho) dispersion profile in various rat tissues (liver, brain, spleen, kidney, heart and skeletal muscle) at low (0.1 T) B(0) field at very low locking field B1, starting from 10 microT. The T(1rho) dispersion profile showed a quite similar pattern in all tissues. The highest R(1rho) relaxation rates were seen in the liver and muscle followed by the heart, whereas the values for spleen, kidney and brain were rather similar. The greatest difference between R2 relaxation rate and R(1rho) relaxation rate at B1=10 microT was seen in the liver and muscle. The steepest slope for a dispersion curve was seen in the muscle. The value of T(1rho) approximately approached the value of T2 when the locking field B1 approached 0. Except for the liver, the calculated apparent relaxation rate R2' was slightly larger than the calculated one. The potential value of T(1rho) imaging is to combine high R1 contrast of low-field imaging with the high signal-to-noise ratio (SNR) of high static field imaging. T(1rho) relaxation and dispersion data presented in the current study help to optimize the rotating-frame MR imaging.
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Affiliation(s)
- Seppo K Koskinen
- Department of Diagnostic Radiology, Turku University Hospital, FIN-20520 Turku, Finland.
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