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Yoon MA, Gold GE, Chaudhari AS. Accelerated Musculoskeletal Magnetic Resonance Imaging. J Magn Reson Imaging 2023. [PMID: 38156716 DOI: 10.1002/jmri.29205] [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: 10/24/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 01/03/2024] Open
Abstract
With a substantial growth in the use of musculoskeletal MRI, there has been a growing need to improve MRI workflow, and faster imaging has been suggested as one of the solutions for a more efficient examination process. Consequently, there have been considerable advances in accelerated MRI scanning methods. This article aims to review the basic principles and applications of accelerated musculoskeletal MRI techniques including widely used conventional acceleration methods, more advanced deep learning-based techniques, and new approaches to reduce scan time. Specifically, conventional accelerated MRI techniques, including parallel imaging, compressed sensing, and simultaneous multislice imaging, and deep learning-based accelerated MRI techniques, including undersampled MR image reconstruction, super-resolution imaging, artifact correction, and generation of unacquired contrast images, are discussed. Finally, new approaches to reduce scan time, including synthetic MRI, novel sequences, and new coil setups and designs, are also reviewed. We believe that a deep understanding of these fast MRI techniques and proper use of combined acceleration methods will synergistically improve scan time and MRI workflow in daily practice. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Min A Yoon
- Department of Radiology, Stanford University, Stanford, California, USA
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Garry E Gold
- Department of Radiology, Stanford University, Stanford, California, USA
- Department of Orthopaedic Surgery, Stanford University, Stanford, California, USA
- Department of Bioengineering, Stanford University, Stanford, California, USA
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Tolpadi AA, Han M, Calivà F, Pedoia V, Majumdar S. Region of interest-specific loss functions improve T 2 quantification with ultrafast T 2 mapping MRI sequences in knee, hip and lumbar spine. Sci Rep 2022; 12:22208. [PMID: 36564430 PMCID: PMC9789075 DOI: 10.1038/s41598-022-26266-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
MRI T2 mapping sequences quantitatively assess tissue health and depict early degenerative changes in musculoskeletal (MSK) tissues like cartilage and intervertebral discs (IVDs) but require long acquisition times. In MSK imaging, small features in cartilage and IVDs are crucial for diagnoses and must be preserved when reconstructing accelerated data. To these ends, we propose region of interest-specific postprocessing of accelerated acquisitions: a recurrent UNet deep learning architecture that provides T2 maps in knee cartilage, hip cartilage, and lumbar spine IVDs from accelerated T2-prepared snapshot gradient-echo acquisitions, optimizing for cartilage and IVD performance with a multi-component loss function that most heavily penalizes errors in those regions. Quantification errors in knee and hip cartilage were under 10% and 9% from acceleration factors R = 2 through 10, respectively, with bias for both under 3 ms for most of R = 2 through 12. In IVDs, mean quantification errors were under 12% from R = 2 through 6. A Gray Level Co-Occurrence Matrix-based scheme showed knee and hip pipelines outperformed state-of-the-art models, retaining smooth textures for most R and sharper ones through moderate R. Our methodology yields robust T2 maps while offering new approaches for optimizing and evaluating reconstruction algorithms to facilitate better preservation of small, clinically relevant features.
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Affiliation(s)
- Aniket A Tolpadi
- Department of Radiology and Biomedical Imaging, University of California, 1700, 4th Street, San Francisco, CA, 94158, USA.
| | - Misung Han
- Department of Radiology and Biomedical Imaging, University of California, 1700, 4th Street, San Francisco, CA, 94158, USA
| | - Francesco Calivà
- Department of Radiology and Biomedical Imaging, University of California, 1700, 4th Street, San Francisco, CA, 94158, USA
| | - Valentina Pedoia
- Department of Radiology and Biomedical Imaging, University of California, 1700, 4th Street, San Francisco, CA, 94158, USA
| | - Sharmila Majumdar
- Department of Radiology and Biomedical Imaging, University of California, 1700, 4th Street, San Francisco, CA, 94158, USA
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Feasibility of an accelerated 2D-multi-contrast knee MRI protocol using deep-learning image reconstruction: a prospective intraindividual comparison with a standard MRI protocol. Eur Radiol 2022; 32:6215-6229. [PMID: 35389046 PMCID: PMC9381615 DOI: 10.1007/s00330-022-08753-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 01/19/2023]
Abstract
OBJECTIVES The aim of this study was to evaluate the image quality and diagnostic performance of a deep-learning (DL)-accelerated two-dimensional (2D) turbo spin echo (TSE) MRI of the knee at 1.5 and 3 T in clinical routine in comparison to standard MRI. MATERIAL AND METHODS Sixty participants, who underwent knee MRI at 1.5 and 3 T between October/2020 and March/2021 with a protocol using standard 2D-TSE (TSES) and DL-accelerated 2D-TSE sequences (TSEDL), were enrolled in this prospective institutional review board-approved study. Three radiologists assessed the sequences regarding structural abnormalities and evaluated the images concerning overall image quality, artifacts, noise, sharpness, subjective signal-to-noise ratio, and diagnostic confidence using a Likert scale (1-5, 5 = best). RESULTS Overall image quality for TSEDL was rated to be excellent (median 5, IQR 4-5), significantly higher compared to TSES (median 5, IQR 4 - 5, p < 0.05), showing significantly lower extents of noise and improved sharpness (p < 0.001). Inter- and intra-reader agreement was almost perfect (κ = 0.92-1.00) for the detection of internal derangement and substantial to almost perfect (κ = 0.58-0.98) for the assessment of cartilage defects. No difference was found concerning the detection of bone marrow edema and fractures. The diagnostic confidence of TSEDL was rated to be comparable to that of TSES (median 5, IQR 5-5, p > 0.05). Time of acquisition could be reduced to 6:11 min using TSEDL compared to 11:56 min for a protocol using TSES. CONCLUSION TSEDL of the knee is clinically feasible, showing excellent image quality and equivalent diagnostic performance compared to TSES, reducing the acquisition time about 50%. KEY POINTS • Deep-learning reconstructed TSE imaging is able to almost halve the acquisition time of a three-plane knee MRI with proton density and T1-weighted images, from 11:56 min to 6:11 min at 3 T. • Deep-learning reconstructed TSE imaging of the knee provided significant improvement of noise levels (p < 0.001), providing higher image quality (p < 0.05) compared to conventional TSE imaging. • Deep-learning reconstructed TSE imaging of the knee had similar diagnostic performance for internal derangement of the knee compared to standard TSE.
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Kim S, Park C, Kim KS, Jeong HS, Lee SM. Clinical feasibility of simultaneous multislice acceleration in knee MRI. Clin Imaging 2021; 82:216-223. [PMID: 34896934 DOI: 10.1016/j.clinimag.2021.11.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/13/2021] [Accepted: 11/27/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE To find the best simultaneous multislice (SMS) accelerated setting for clinical application in knee MRI. MATERIAL AND METHODS Thirty-three patients (mean age, 54 years; 21 women) who underwent knee MRI (conventional/SMS sequences) between June and October 2020 were enrolled. Two radiologists retrospectively evaluated sagittal T1- and T2-weighted conventional (2-fold parallel acquisition technique [PAT-2]) and SMS (SMS-2 [PAT-2 with 2-fold SMS], SMS-3, and SMS-4) images. For qualitative analysis, artifacts (zebra/residual aliasing) and diagnostic confidence for internal derangement of knee (bone marrow, cartilage, meniscus, anterior cruciate ligament, and synovium abnormalities) were evaluated. For quantitative analysis, contrast-to-noise ratios of bone marrow, meniscus, joint effusion, and ligament were evaluated. RESULTS Compared to PAT-2 (2 min 32 s), mean acquisition time was reduced by 47% in SMS-2; 64%, SMS-3; and 70%, SMS-4. In qualitative analysis, zebra artifacts were only seen on T2-weighted SMS images. The more SMS was applied, the more zebra and residual aliasing artifacts were seen and the lower diagnostic confidence was for internal derangement. However, qualitative analysis showed acceptable image quality in SMS-2 and SMS-3 images, but not in SMS-4 images. In quantitative analysis, SMS-4 images showed the lowest contrast-to-noise ratios and there were no significant differences among PAT-2, SMS-2, and SMS-3 images. CONCLUSION Applying SMS-3 to knee MRI reduced scan time and showed acceptable image quality compared to conventional (PAT-2). However, when evaluating SMS images, radiologists should know that when more SMS is applied, more zebra and residual aliasing artifacts appear.
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Affiliation(s)
- Shinyoung Kim
- Department of Radiology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Chankue Park
- Department of Radiology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea.
| | | | - Hee Seok Jeong
- Department of Radiology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
| | - Sang-Min Lee
- Department Orthopedic Surgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea
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Advanced Imaging Techniques in the Knee: Benefits and Limitations of New Rapid Acquisition Strategies for Routine Knee MRI. AJR Am J Roentgenol 2017. [DOI: 10.2214/ajr.17.18228] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Shapiro LM, McWalter EJ, Son MS, Levenston M, Hargreaves BA, Gold GE. Mechanisms of osteoarthritis in the knee: MR imaging appearance. J Magn Reson Imaging 2014; 39:1346-56. [PMID: 24677706 DOI: 10.1002/jmri.24562] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 07/14/2013] [Indexed: 01/15/2023] Open
Abstract
Osteoarthritis has grown to become a widely prevalent disease that has major implications in both individual and public health. Although originally considered to be a degenerative disease driven by "wear and tear" of the articular cartilage, recent evidence has led to a consensus that osteoarthritis pathophysiology should be perceived in the context of the entire joint and multiple tissues. MRI is becoming an increasingly more important modality for imaging osteoarthritis, due to its excellent soft tissue contrast and ability to acquire morphological and biochemical data. This review will describe the pathophysiology of osteoarthritis as it is associated with various tissue types, highlight several promising MR imaging techniques for osteoarthritis and illustrate the expected appearance of osteoarthritis with each technique.
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Affiliation(s)
- Lauren M Shapiro
- Department of Radiology, Stanford University, Stanford, California, USA
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Braun HJ, Dragoo JL, Hargreaves BA, Levenston ME, Gold GE. Application of advanced magnetic resonance imaging techniques in evaluation of the lower extremity. Radiol Clin North Am 2013; 51:529-45. [PMID: 23622097 PMCID: PMC3639445 DOI: 10.1016/j.rcl.2012.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This article reviews current magnetic resonance imaging (MR imaging) techniques for imaging the lower extremity, focusing on imaging of the knee, ankle, and hip joints. Recent advancements in MR imaging include imaging at 7 T, using multiple receiver channels, T2* imaging, and metal suppression techniques, allowing more detailed visualization of complex anatomy, evaluation of morphologic changes within articular cartilage, and imaging around orthopedic hardware.
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Affiliation(s)
- Hillary J. Braun
- Department of Radiology, Stanford University
- Department of Orthopaedic Surgery, Stanford University
| | | | - Brian A. Hargreaves
- Department of Radiology, Stanford University
- Department of Bioengineering, Stanford University
| | | | - Garry E. Gold
- Department of Radiology, Stanford University
- Department of Orthopaedic Surgery, Stanford University
- Department of Bioengineering, Stanford University
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Abstract
Osteoarthritis (OA) is a chronic, debilitating joint disease characterized by degenerative changes to the bones, cartilage, menisci, ligaments, and synovial tissue. Imaging modalities such as radiography, magnetic resonance imaging (MRI), optical coherence tomography (OCT), and ultrasound (US) permit visualization of these structures and can evaluate disease onset and progression. Radiography is primarily useful for the assessment of bony structures, while OCT is used for evaluation of articular cartilage and US for ligaments and the synovium. MRI permits visualization of all intraarticular structures and pathologies, though US or OCT may be preferential in some circumstances. As OA is a disease of the whole joint, a combination of imaging techniques may be necessary in order to gain the most comprehensive picture of the disease state. This article is part of a Special Issue entitled "Osteoarthritis".
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Doria AS, Chaudry GA, Nasui C, Rayner T, Wang C, Moineddin R, Babyn PS, White LM, Sussman MS. The use of parallel imaging for MRI assessment of knees in children and adolescents. Pediatr Radiol 2010; 40:284-93. [PMID: 19949946 DOI: 10.1007/s00247-009-1426-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 09/02/2009] [Indexed: 11/29/2022]
Abstract
BACKGROUND Parallel imaging provides faster scanning at the cost of reduced signal-to-noise ratio (SNR) and increased artifacts. OBJECTIVE To compare the diagnostic performance of two parallel MRI protocols (PPs) for assessment of pathologic knees using an 8-channel knee coil (reference standard, conventional protocol [CP]) and to characterize the SNR losses associated with parallel imaging. MATERIALS AND METHODS Two radiologists blindly interpreted 1.5 Tesla knee MRI images in 21 children (mean 13 years, range 9-18 years) with clinical indications for an MRI scan. Sagittal proton density, T2-W fat-saturated FSE, axial T2-W fat-saturated FSE, and coronal T1-W (NEX of 1,1,1) images were obtained with both CP and PP. Images were read for soft tissue and osteochondral findings. RESULTS There was a 75% decrease in acquisition time using PP in comparison to CP. The CP and PP protocols fell within excellent or upper limits of substantial agreement: CP, kappa coefficient, 0.81 (95% CIs, 0.73-0.89); PP, 0.80-0.81 (0.73-0.89). The sensitivity of the two PPs was similar for assessment of soft (0.98-1.00) and osteochondral (0.89-0.94) tissues. Phantom data indicated an SNR of 1.67, 1.6, and 1.51 (axial, sagittal and coronal planes) between CP and PP scans. CONCLUSION Parallel MRI provides a reliable assessment for pediatric knees in a significantly reduced scan time without affecting the diagnostic performance of MRI.
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Trattnig S, Mamisch TC, Noebauer I. [High-field and ultrahigh-field magnetic resonance imaging: new possibilities for imaging joints]. Z Rheumatol 2009; 65:681-7. [PMID: 17106667 DOI: 10.1007/s00393-006-0121-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Whole-body MR tomography at 3 T is moving steadily from research into routine clinical practice. The most important advantage of high-field MRI is the higher signal to noise ratio, which allows acquisitions in the musculo-skeletal system with higher resolution within the same scan time. The imaging of small joints, the visualization of labral anatomy and pathology in the shoulder and hip joints, as well as cartilage imaging will benefit from higher resolution protocols. In addition to improved morphological imaging of articular cartilage, the higher sensitivity of 3 T allows the clinical use of advanced MR techniques of cartilage such as T1 and T2 mapping, diffusion and sodium imaging. The improved spectral resolution with the higher field may improve metabolic imaging of tumors of the skeleton and soft tissues.
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Affiliation(s)
- S Trattnig
- Exzellenzzentrum Hochfeld-MR, Universitäts-Klinik für Radiodiagnostik, Medizinische Universität Wien, Osterreich.
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Fox MG. MR imaging of the meniscus: review, current trends, and clinical implications. Radiol Clin North Am 2008; 45:1033-53, vii. [PMID: 17981182 DOI: 10.1016/j.rcl.2007.08.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
MR imaging is the preferred imaging modality for evaluating the meniscus. Overall, when strict criteria are followed, it is accurate in diagnosing meniscal tears in patients who have not had prior meniscal surgery. However, an accurate interpretation requires a through knowledge of the normal meniscal anatomy, common meniscal variants, and common diagnostic pitfalls. In this article, the author emphasizes the importance of describing meniscal tears properly and discusses treatment options. Diagnosing a recurrent tear is more complicated in patients who have had prior partial meniscal resection or repair, and the use of MR arthrography in this group of patients is discussed. Recent developments in areas such as 3 T and parallel imaging offer promise for accurate meniscal evaluation with even shorter scan times.
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Affiliation(s)
- Michael G Fox
- Division of Musculoskeletal Radiology, Department of Radiology, University of Virginia, Charlottesville, VA 22908, USA.
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Bauer JS, Banerjee S, Henning TD, Krug R, Majumdar S, Link TM. Fast High-Spatial-Resolution MRI of the Ankle with Parallel Imaging Using GRAPPA at 3 T. AJR Am J Roentgenol 2007; 189:240-5. [PMID: 17579177 DOI: 10.2214/ajr.07.2066] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of our study was to compare an autocalibrating parallel imaging technique at 3 T with standard acquisitions at 3 and 1.5 T for small-field-of-view imaging of the ankle. MATERIALS AND METHODS MRI of the ankle was performed in three fresh human cadaver specimens and three healthy volunteers. Axial and sagittal T1-weighted, axial fat-saturated T2-weighted, and coronal intermediate-weighted fast spin-echo sequences, as well as a fat-saturated spoiled gradient-echo sequence, were acquired at 1.5 and 3 T. At 3 T, reduced data sets were reconstructed using a generalized autocalibrating partially parallel acquisition (GRAPPA) technique, with a scan time reduction of approximately 44%. All images were assessed by two radiologists independently concerning image quality. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured in every data set. In the cadaver specimens, macroscopic findings after dissection served as a reference for the pathologic evaluation. RESULTS SNR and CNR in the GRAPPA images were comparable to the standard acquisition at 3 T. The image quality was rated significantly higher at 3 T with both normal and parallel acquisition compared with 1.5 T. There was no significant difference in ligament and cartilage visualization or in image quality between standard and GRAPPA reconstruction at 3 T. Ankle abnormalities were better seen at 3 T than at 1.5 T for both normal and parallel acquisitions. CONCLUSION Using higher field strength combined with parallel technique, MR images of the ankle were obtained with excellent diagnostic quality and a scan time reduction of about 44%. In addition, parallel imaging can provide more flexibility in protocol design.
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Affiliation(s)
- Jan Stefan Bauer
- Department of Radiology, University of California at San Francisco, San Francisco, CA, USA.
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Fox MG. MR Imaging of the Meniscus: Review, Current Trends, and Clinical Implications. Magn Reson Imaging Clin N Am 2007; 15:103-23. [PMID: 17499184 DOI: 10.1016/j.mric.2007.02.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
MR imaging is the preferred imaging modality for evaluating the meniscus. Overall, when strict criteria are followed, it is accurate in diagnosing meniscal tears in patients who have not had prior meniscal surgery. However, an accurate interpretation requires a through knowledge of the normal meniscal anatomy, common meniscal variants, and common diagnostic pitfalls. In this article, the author emphasizes the importance of describing meniscal tears properly and discusses treatment options. Diagnosing a recurrent tear is more complicated in patients who have had prior partial meniscal resection or repair, and the use of MR arthrography in this group of patients is discussed. Recent developments in areas such as 3 T and parallel imaging offer promise for accurate meniscal evaluation with even shorter scan times.
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Affiliation(s)
- Michael G Fox
- Division of Musculoskeletal Radiology, Department of Radiology, University of Virginia, Box 800170, Charlottesville, VA 22908, USA.
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Kreitner KF, Romaneehsen B, Krummenauer F, Oberholzer K, Müller LP, Düber C. Fast magnetic resonance imaging of the knee using a parallel acquisition technique (mSENSE): a prospective performance evaluation. Eur Radiol 2006; 16:1659-66. [PMID: 16733683 DOI: 10.1007/s00330-006-0288-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 04/05/2006] [Accepted: 04/07/2006] [Indexed: 11/26/2022]
Abstract
The performance of a magnetic resonance (MR) imaging strategy that uses multiple receiver coil elements and integrated parallel imaging techniques (iPAT) in traumatic and degenerative disorders of the knee and to compare this technique with a standard MR imaging protocol was evaluated. Ninety patients with suspected internal derangements of the knee joint prospectively underwent MR imaging at 1.5 T. For signal detection, a 6-channel array coil was used. All patients were investigated with a standard imaging protocol consisting of different turbo spin-echo sequences proton density (PD), T2-weighted turbo spin echo (TSE) with and without fat suppression) in three imaging planes. All sequences were repeated with an integrated parallel acquisition technique (iPAT) using the modified sensitivity encoding (mSENSE) algorithm with an acceleration factor of 2. Two radiologists independently evaluated and scored all images with regard to overall image quality, artefacts and pathologic findings. Agreement of the parallel ratings between readers and imaging techniques, respectively, was evaluated by means of pairwise kappa coefficients that were stratified for the area of evaluation. Agreement between the parallel readers for both the iPAT imaging and the conventional technique, respectively, as well as between imaging techniques was found encouraging with inter-observer kappa values ranging between 0.78 and 0.98 for both imaging techniques, and the inter-method kappa values ranging between 0.88 and 1.00 for both clinical readers. All pathological findings (e.g. occult fractures, meniscal and cruciate ligament tears, torn and interpositioned Hoffa's cleft, cartilage damage) were detected by both techniques with comparable performance. The use of iPAT lead to a 48% reduction of acquisition time compared with standard technique. Parallel imaging using mSENSE proved to be an efficient and economic tool for fast musculoskeletal MR imaging of the knee joint with comparable diagnostic performance to conventional MR imaging.
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Affiliation(s)
- Karl-Friedrich Kreitner
- Department of Diagnostic and Interventional Radiology, Johannes Gutenberg-University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany.
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