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  1. Article ; Online: Development and Stability Analysis of Carpal Kinematic Metrics from 4D Magnetic Resonance Imaging.

    Sharafi, Azadeh / Nencka, Andrew S / Koch, Kevin M

    ArXiv

    2023  

    Abstract: Introduction: Wrist instability remains a common health concern. The potential of dynamic Magnetic Resonance Imaging (MRI) in assessing carpal dynamics associated with this condition is a field of ongoing research. This study contributes to this line of ...

    Abstract Introduction: Wrist instability remains a common health concern. The potential of dynamic Magnetic Resonance Imaging (MRI) in assessing carpal dynamics associated with this condition is a field of ongoing research. This study contributes to this line of inquiry by developing MRI-derived carpal kinematic metrics and investigating their stability.
    Methods: A previously described 4D MRI approach for tracking the movements of carpal bones in the wrist was deployed in this study. A panel of 120 metrics characterizing radial/ulnar deviation and flexion extension movements was constructed by fitting low order polynomial models of scaphoid and lunate degrees of freedom against that of the capitate. Intraclass Correlation Coefficients were utilized to analyze intra- and inter-subject stability within a mixed cohort of 49 subjects, including 20 with and 29 without a history of wrist injury.
    Results: A comparable degree of stability across the two different wrist movements. Out of the total 120 derived metrics, distinct subsets demonstrated high stability within each type of movement. Among asymptomatic subjects, 16 out of 17 metrics with high intra-subject stability also showed high inter-subject stability. Interestingly, some quadratic term metrics, although relatively unstable within asymptomatic subjects, showed increased stability within this group, hinting at potential differentiation in their behavior across different cohorts.
    Conclusion: This study showed the developing potential of dynamic MRI to characterize complex carpal bone dynamics. Stability analyses of the derived kinematic metrics showed encouraging differences between cohorts with and without a history of wrist injury. Although these broad metric stability variations highlight the potential utility of this approach for analysis of carpal instability, further studies are necessary to better characterize these observations.
    Language English
    Publishing date 2023-05-25
    Publishing country United States
    Document type Preprint
    ISSN 2331-8422
    ISSN (online) 2331-8422
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Development and Stability Analysis of Carpal Kinematic Metrics from 4D Magnetic Resonance Imaging

    Sharafi, Azadeh / Nencka, Andrew S / Koch, Kevin M

    2023  

    Abstract: Introduction: Wrist instability remains a common health concern. The potential of dynamic Magnetic Resonance Imaging (MRI) in assessing carpal dynamics associated with this condition is a field of ongoing research. This study contributes to this line of ... ...

    Abstract Introduction: Wrist instability remains a common health concern. The potential of dynamic Magnetic Resonance Imaging (MRI) in assessing carpal dynamics associated with this condition is a field of ongoing research. This study contributes to this line of inquiry by developing MRI-derived carpal kinematic metrics and investigating their stability. Methods: A previously described 4D MRI approach for tracking the movements of carpal bones in the wrist was deployed in this study. A panel of 120 metrics characterizing radial/ulnar deviation and flexion extension movements was constructed by fitting low order polynomial models of scaphoid and lunate degrees of freedom against that of the capitate. Intraclass Correlation Coefficients were utilized to analyze intra- and inter-subject stability within a mixed cohort of 49 subjects, including 20 with and 29 without a history of wrist injury. Results: A comparable degree of stability across the two different wrist movements. Out of the total 120 derived metrics, distinct subsets demonstrated high stability within each type of movement. Among asymptomatic subjects, 16 out of 17 metrics with high intra-subject stability also showed high inter-subject stability. Interestingly, some quadratic term metrics, although relatively unstable within asymptomatic subjects, showed increased stability within this group, hinting at potential differentiation in their behavior across different cohorts. Conclusion: This study showed the developing potential of dynamic MRI to characterize complex carpal bone dynamics. Stability analyses of the derived kinematic metrics showed encouraging differences between cohorts with and without a history of wrist injury. Although these broad metric stability variations highlight the potential utility of this approach for analysis of carpal instability, further studies are necessary to better characterize these observations.

    Comment: 15 pages, 10 figure, 1 table
    Keywords Physics - Medical Physics
    Subject code 621
    Publishing date 2023-05-25
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Optimization of spin-lock times in T

    Zibetti, Marcelo V W / Sharafi, Azadeh / Regatte, Ravinder R

    Magnetic resonance in medicine

    2021  Volume 87, Issue 3, Page(s) 1418–1434

    Abstract: Purpose: To compare different optimization approaches for choosing the spin-lock times (TSLs), in spin-lattice relaxation time in the rotating frame (T: Methods: Optimization criteria for TSLs based on Cramér-Rao lower bounds (CRLB) are compared with ...

    Abstract Purpose: To compare different optimization approaches for choosing the spin-lock times (TSLs), in spin-lattice relaxation time in the rotating frame (T
    Methods: Optimization criteria for TSLs based on Cramér-Rao lower bounds (CRLB) are compared with matched sampling-fitting (MSF) approaches for T
    Results: All optimized criteria were better than non-optimized ones. However, we observe that a modified CRLB and an MSF based on the mean of the normalized absolute error (MNAE) were more robust optimization approaches, performing well in all tested cases. The optimized TSLs obtained the best performance with synthetic data (3.5-8.0% error), model phantoms (1.5-2.8% error), and healthy volunteers (7.7-21.1% error), showing stable and improved quality results, comparing to non-optimized approaches (4.2-13.3% error on synthetic data, 2.1-6.2% error on model phantoms, 9.8-27.8% error on healthy volunteers).
    Conclusion: A modified CRLB and the MSF based on MNAE are robust optimization approaches for choosing TSLs in T
    MeSH term(s) Cartilage, Articular/diagnostic imaging ; Humans ; Knee ; Knee Joint/diagnostic imaging ; Magnetic Resonance Imaging ; Phantoms, Imaging
    Language English
    Publishing date 2021-11-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 605774-3
    ISSN 1522-2594 ; 0740-3194
    ISSN (online) 1522-2594
    ISSN 0740-3194
    DOI 10.1002/mrm.29063
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: 3D magnetic resonance fingerprinting for rapid simultaneous T1, T2, and T1ρ volumetric mapping of human articular cartilage at 3 T.

    Sharafi, Azadeh / Zibetti, Marcelo V W / Chang, Gregory / Cloos, Martijn / Regatte, Ravinder R

    NMR in biomedicine

    2022  Volume 35, Issue 12, Page(s) e4800

    Abstract: Quantitative MRI can detect early biochemical changes in cartilage; however, the conventional techniques only measure one parameter (e.g., ... ...

    Abstract Quantitative MRI can detect early biochemical changes in cartilage; however, the conventional techniques only measure one parameter (e.g., T
    MeSH term(s) Humans ; Adult ; Middle Aged ; Cartilage, Articular/diagnostic imaging ; Cartilage, Articular/pathology ; Reproducibility of Results ; Magnetic Resonance Imaging/methods ; Knee Joint/diagnostic imaging ; Osteoarthritis, Knee/diagnostic imaging ; Osteoarthritis, Knee/pathology ; Magnetic Resonance Spectroscopy
    Language English
    Publishing date 2022-07-30
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1000976-0
    ISSN 1099-1492 ; 0952-3480
    ISSN (online) 1099-1492
    ISSN 0952-3480
    DOI 10.1002/nbm.4800
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Age-Dependent Changes in Knee Cartilage T

    Kijowski, Richard / Sharafi, Azadeh / Zibetti, Marcelo V W / Chang, Gregory / Cloos, Martijn A / Regatte, Ravinder R

    Journal of magnetic resonance imaging : JMRI

    2022  Volume 57, Issue 6, Page(s) 1805–1812

    Abstract: Background: Magnetic resonance fingerprinting (MRF) techniques have been recently described for simultaneous multiparameter cartilage mapping of the knee although investigation of their ability to detect early cartilage degeneration remains limited.: ... ...

    Abstract Background: Magnetic resonance fingerprinting (MRF) techniques have been recently described for simultaneous multiparameter cartilage mapping of the knee although investigation of their ability to detect early cartilage degeneration remains limited.
    Purpose: To investigate age-dependent changes in knee cartilage T
    Study type: Prospective.
    Subjects: The study group consisted of 24 healthy asymptomatic human volunteers (15 males with mean age 34.9 ± 14.4 years and 9 females with mean age 44.5 ± 13.1 years).
    Field strength/sequence: A 3.0 T gradient-echo-based 3D-MRF sequence was used to simultaneously create proton density-weighted images and T
    Assessment: Mean global cartilage and regional cartilage (lateral femur, lateral tibia, medial femur, medial tibia, and patella) T
    Statistical tests: Kruskal-Wallis tests were used to compared cartilage T
    Results: Higher age groups showed higher global and regional cartilage T
    Conclusion: Cartilage T
    MeSH term(s) Male ; Female ; Humans ; Young Adult ; Adult ; Middle Aged ; Prospective Studies ; Cartilage, Articular/diagnostic imaging ; Cartilage, Articular/pathology ; Knee Joint/diagnostic imaging ; Knee Joint/pathology ; Knee ; Magnetic Resonance Imaging/methods
    Language English
    Publishing date 2022-10-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1146614-5
    ISSN 1522-2586 ; 1053-1807
    ISSN (online) 1522-2586
    ISSN 1053-1807
    DOI 10.1002/jmri.28451
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Three-dimensional multi-parameter brain mapping using MR fingerprinting.

    Menon, Rajiv G / Sharafi, Azadeh / Muccio, Marco / Smith, Tyler / Kister, Ilya / Ge, Yulin / Regatte, Ravinder R

    Research square

    2023  

    Abstract: The purpose of this study was to develop and test a 3D multi-parameter MR fingerprinting (MRF) method for brain imaging applications. The subject cohort included 5 healthy volunteers, repeatability tests done on 2 healthy volunteers and tested on two ... ...

    Abstract The purpose of this study was to develop and test a 3D multi-parameter MR fingerprinting (MRF) method for brain imaging applications. The subject cohort included 5 healthy volunteers, repeatability tests done on 2 healthy volunteers and tested on two multiple sclerosis (MS) patients. A 3D-MRF imaging technique capable of quantifying T
    Language English
    Publishing date 2023-03-24
    Publishing country United States
    Document type Preprint
    DOI 10.21203/rs.3.rs-2675278/v1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Age and Gender-Dependence of Single-and Bi-Exponential T

    Lise de Moura, Hector / Kijowski, Richard / Zhang, Xiaoxia / Sharafi, Azadeh / Zibetti, Marcelo V W / Regatte, Ravinder

    Journal of magnetic resonance imaging : JMRI

    2023  

    Abstract: Background: There is limited understanding of differences in the composition and structure of ligaments between healthy males and females, and individuals of different ages. Females present higher risk for ligament injuries than males and there are ... ...

    Abstract Background: There is limited understanding of differences in the composition and structure of ligaments between healthy males and females, and individuals of different ages. Females present higher risk for ligament injuries than males and there are conflicting reports on its cause. This study looks into T
    Purpose: To investigate gender-related and age-related differences in T
    Study type: Prospective.
    Population: The study group consisted of 22 healthy subjects (11 females, ages: 41 ± 18 years, and 11 males, ages: 41 ± 14 years) with no known inflammation, trauma, or pain in the knee joint.
    Field strength/sequence: A T
    Assessment: Monoexponential, biexponential, and stretched-exponential 3D-PETRA-T
    Statistical tests: Mann-Whitney U-tests were used to compare 3D-PETRA-T
    Results: Significant correlations with age were found the three ligaments with most of the measured T
    Data conclusion: 3D-PETRA-T
    Level of evidence: 2 TECHNICAL EFFICACY: Stage 1.
    Language English
    Publishing date 2023-10-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1146614-5
    ISSN 1522-2586 ; 1053-1807
    ISSN (online) 1522-2586
    ISSN 1053-1807
    DOI 10.1002/jmri.29084
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Fast multicomponent 3D-T

    Zibetti, Marcelo V W / Helou, Elias S / Sharafi, Azadeh / Regatte, Ravinder R

    NMR in biomedicine

    2020  Volume 33, Issue 12, Page(s) e4318

    Abstract: NMR relaxometry can provide information about the relaxation of the magnetization in different tissues, increasing our understanding of molecular dynamics and biochemical composition in biological systems. In general, tissues have complex and ... ...

    Abstract NMR relaxometry can provide information about the relaxation of the magnetization in different tissues, increasing our understanding of molecular dynamics and biochemical composition in biological systems. In general, tissues have complex and heterogeneous structures composed of multiple pools. As a result, bulk magnetization returns to its original state with different relaxation times, in a multicomponent relaxation. Recovering the distribution of relaxation times in each voxel is a difficult inverse problem; it is usually unstable and requires long acquisition time, especially on clinical scanners. MRI can also be viewed as an inverse problem, especially when compressed sensing (CS) is used. The solution of these two inverse problems, CS and relaxometry, can be obtained very efficiently in a synergistically combined manner, leading to a more stable multicomponent relaxometry obtained with short scan times. In this paper, we will discuss the details of this technique from the viewpoint of inverse problems.
    MeSH term(s) Algorithms ; Animals ; Cartilage, Articular/diagnostic imaging ; Cattle ; Liver/diagnostic imaging ; Magnetic Resonance Imaging ; Phantoms, Imaging
    Language English
    Publishing date 2020-05-02
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1000976-0
    ISSN 1099-1492 ; 0952-3480
    ISSN (online) 1099-1492
    ISSN 0952-3480
    DOI 10.1002/nbm.4318
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Simultaneous bilateral T

    Sharafi, Azadeh / Zibetti, Marcelo V W / Chang, Gregory / Cloos, Martijn A / Regatte, Ravinder R

    NMR in biomedicine

    2021  Volume 35, Issue 5, Page(s) e4651

    Abstract: Quantitative MRI can detect early biochemical changes in cartilage, but its bilateral use in clinical routines is challenging. The aim of this prospective study was to demonstrate the feasibility of magnetic resonance fingerprinting for bilateral ... ...

    Abstract Quantitative MRI can detect early biochemical changes in cartilage, but its bilateral use in clinical routines is challenging. The aim of this prospective study was to demonstrate the feasibility of magnetic resonance fingerprinting for bilateral simultaneous T
    MeSH term(s) Cartilage, Articular/diagnostic imaging ; Cartilage, Articular/pathology ; Hip Joint/diagnostic imaging ; Hip Joint/pathology ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Prospective Studies
    Language English
    Publishing date 2021-11-26
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1000976-0
    ISSN 1099-1492 ; 0952-3480
    ISSN (online) 1099-1492
    ISSN 0952-3480
    DOI 10.1002/nbm.4651
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: 3D-T

    Sharafi, Azadeh / Baboli, Rahman / Chang, Gregory / Regatte, Ravinder R

    Journal of magnetic resonance imaging : JMRI

    2019  Volume 50, Issue 4, Page(s) 1207–1218

    Abstract: Background: In addition to the articular cartilage, osteoarthritis (OA) affects several other tissues such as tendons, ligaments, and subchondral bone. T1: Purpose: To develop a 3D spin-lattice relaxation in the rotating frame (T: Study type: ... ...

    Abstract Background: In addition to the articular cartilage, osteoarthritis (OA) affects several other tissues such as tendons, ligaments, and subchondral bone. T1
    Purpose: To develop a 3D spin-lattice relaxation in the rotating frame (T
    Study type: Prospective.
    Population: Phantom, two bovine whole knee joint and Achilles tendon specimens, 10 healthy volunteers with no known inflammation, trauma or pain in the knee or ankle.
    Field strength/sequence: A customized PETRA sequence to acquire fat-suppressed 3D T
    Assessment: Mono- and biexponential T
    Statistical tests: Kruskal-Wallis with post-hoc Dunn's test for multiple pairwise comparisons.
    Results: Phantom and ex vivo studies showed the feasibility of T
    Data conclusion: The 3D-T
    Level of evidence: 2 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1207-1218.
    MeSH term(s) Achilles Tendon/anatomy & histology ; Adult ; Animals ; Ankle Joint/anatomy & histology ; Cattle ; Feasibility Studies ; Female ; Healthy Volunteers ; Humans ; Image Processing, Computer-Assisted/methods ; Imaging, Three-Dimensional/methods ; Knee Joint/anatomy & histology ; Magnetic Resonance Imaging/methods ; Male ; Models, Animal ; Phantoms, Imaging ; Prospective Studies ; Reference Values
    Language English
    Publishing date 2019-01-28
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1146614-5
    ISSN 1522-2586 ; 1053-1807
    ISSN (online) 1522-2586
    ISSN 1053-1807
    DOI 10.1002/jmri.26664
    Database MEDical Literature Analysis and Retrieval System OnLINE

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