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Athertya JS, Suprana A, Lo J, Lombardi AF, Moazamian D, Chang EY, Du J, Ma Y. Quantitative ultrashort echo time MR imaging of knee osteochondral junction: An ex vivo feasibility study. NMR IN BIOMEDICINE 2024:e5253. [PMID: 39197467 DOI: 10.1002/nbm.5253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 08/12/2024] [Accepted: 08/19/2024] [Indexed: 09/01/2024]
Abstract
Compositional changes can occur in the osteochondral junction (OCJ) during the early stages and progressive disease evolution of knee osteoarthritis (OA). However, conventional magnetic resonance imaging (MRI) sequences are not able to image these regions efficiently because of the OCJ region's rapid signal decay. The development of new sequences able to image and quantify OCJ region is therefore highly desirable. We developed a comprehensive ultrashort echo time (UTE) MRI protocol for quantitative assessment of OCJ region in the knee joint, including UTE variable flip angle technique for T1 mapping, UTE magnetization transfer (UTE-MT) modeling for macromolecular proton fraction (MMF) mapping, UTE adiabatic T1ρ (UTE-AdiabT1ρ) sequence for T1ρ mapping, and multi-echo UTE sequence for T2* mapping. B1 mapping based on the UTE actual flip angle technique was utilized for B1 correction in T1, MMF, and T1ρ measurements. Ten normal and one abnormal cadaveric human knee joints were scanned on a 3T clinical MRI scanner to investigate the feasibility of OCJ imaging using the proposed protocol. Volumetric T1, MMF, T1ρ, and T2* maps of the OCJ, as well as the superficial and full-thickness cartilage regions, were successfully produced using the quantitative UTE imaging protocol. Significantly lower T1, T1ρ, and T2* relaxation times were observed in the OCJ region compared with those observed in both the superficial and full-thickness cartilage regions, whereas MMF showed significantly higher values in the OCJ region. In addition, all four UTE biomarkers showed substantial differences in the OCJ region between normal and abnormal knees. These results indicate that the newly developed 3D quantitative UTE imaging techniques are feasible for T1, MMF, T1ρ, and T2* mapping of knee OCJ, representative of a promising approach for the evaluation of compositional changes in early knee OA.
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Affiliation(s)
- Jiyo S Athertya
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Arya Suprana
- Department of Radiology, University of California San Diego, San Diego, California, USA
- Department of Bioengineering, University of California San Diego, San Diego, California, USA
| | - James Lo
- Department of Radiology, University of California San Diego, San Diego, California, USA
- Department of Bioengineering, University of California San Diego, San Diego, California, USA
| | - Alecio F Lombardi
- Department of Radiology, University of California San Diego, San Diego, California, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, California, USA
| | - Dina Moazamian
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, San Diego, California, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, California, USA
- Department of Bioengineering, University of California San Diego, San Diego, California, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, California, USA
| | - Yajun Ma
- Department of Radiology, University of California San Diego, San Diego, California, USA
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Athertya JS, Statum S, Chen X, Du K, Shin SH, Jerban S, Chung CB, Chang EY, Ma Y. Evaluation of spine disorders using high contrast imaging of the cartilaginous endplate. Front Physiol 2024; 15:1394189. [PMID: 38860112 PMCID: PMC11163041 DOI: 10.3389/fphys.2024.1394189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 05/13/2024] [Indexed: 06/12/2024] Open
Abstract
Introduction: Many spine disorders are caused by disc degeneration or endplate defects. Because nutrients entering the avascular disc are channeled through the cartilaginous endplate (CEP), structural and compositional changes in the CEP may block this solute channel, thereby hindering disc cell function. Therefore, imaging the CEP region is important to improve the diagnostic accuracy of spine disorders. Methods: A clinically available T1-weighted and fat-suppressed spoiled gradient recalled-echo (FS-SPGR) sequence was optimized for high-contrast CEP imaging, which utilizes the short T1 property of the CEP. The FS-SPGR scans with and without breath-hold were performed for comparison on healthy subjects. Then, the FS-SPGR sequence which produced optimal image quality was employed for patient scans. In this study, seven asymptomatic volunteers and eight patients with lower back pain were recruited and scanned on a 3T whole-body MRI scanner. Clinical T2-weighted fast spin-echo (T2w-FSE) and T1-weighted FSE (T1w-FSE) sequences were also scanned for comparison. Results: For the asymptomatic volunteers, the FS-SPGR scans under free breathing conditions with NEX = 4 showed much higher contrast-to-noise ratio values between the CEP and bone marrow fat (BMF) (CNRCEP-BMF) (i.e., 7.8 ± 1.6) and between the CEP and nucleus pulposus (NP) (CNRCEP-NP) (i.e., 6.1 ± 1.2) compared to free breathing with NEX = 1 (CNRCEP-BMF: 4.0 ± 1.1 and CNRCEP-NP: 2.5 ± 0.9) and breath-hold condition with NEX = 1 (CNRCEP-BMF: 4.2 ± 1.3 and CNRCEP-NP: 2.8 ± 1.3). The CEP regions showed bright linear signals with high contrast in the T1-weighted FS-SPGR images in the controls, while irregularities of the CEP were found in the patients. Discussion: We have developed a T1-weighted 3D FS-SPGR sequence to image the CEP that is readily translatable to clinical settings. The proposed sequence can be used to highlight the CEP region and shows promise for the detection of intervertebral disc abnormalities.
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Affiliation(s)
- Jiyo S. Athertya
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Sheronda Statum
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Xiaojun Chen
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Kevin Du
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Soo Hyun Shin
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
| | - Christine B. Chung
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, San Diego, CA, United States
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Cheng KY, Moazamian D, Ma Y, Jang H, Jerban S, Du J, Chung CB. Clinical application of ultrashort echo time (UTE) and zero echo time (ZTE) magnetic resonance (MR) imaging in the evaluation of osteoarthritis. Skeletal Radiol 2023; 52:2149-2157. [PMID: 36607355 PMCID: PMC10323038 DOI: 10.1007/s00256-022-04269-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/13/2022] [Accepted: 12/13/2022] [Indexed: 01/07/2023]
Abstract
Novel compositional magnetic resonance (MR) imaging techniques have allowed for both the qualitative and quantitative assessments of tissue changes in osteoarthritis, many of which are difficult to characterize on conventional MR imaging. Ultrashort echo time (UTE) and zero echo time (ZTE) MR imaging have not been broadly implemented clinically but have several applications that leverage contrast mechanisms for morphologic evaluation of bone and soft tissue, as well as biochemical assessment in various stages of osteoarthritis progression. Many of the musculoskeletal tissues implicated in the initiation and progression of osteoarthritis are short T2 in nature, appearing dark as signal has already decayed to its minimum when image sampling starts. UTE and ZTE MR imaging allow for the qualitative and quantitative assessments of these short T2 tissues (bone, tendon, calcified cartilage, meniscus, and ligament) with both structural and functional reference standards described in the literature [1-3]. This review will describe applications of UTE and ZTE MR imaging in musculoskeletal tissues focusing on its role in knee osteoarthritis. While the review will address tissue-specific applications of these sequences, it is understood that osteoarthritis is a whole joint process with involvement and interdependence of all tissues. KEY POINTS: • UTE MR imaging allows for the qualitative and quantitative evaluation of short T2 tissues (bone, calcified cartilage, and meniscus), enabling identification of both early degenerative changes and subclinical injuries that may predispose to osteoarthritis. • ZTE MR imaging allows for the detection of signal from bone, which has some of the shortest T2 values, and generates tissue contrast similar to CT, potentially obviating the need for CT in the assessment of osseous features of osteoarthritis.
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Affiliation(s)
- Karen Y Cheng
- Department of Radiology, University of California, San Diego, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, USA
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
- Department of Orthopedic Surgery, University of California, San Diego, San Diego, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
- Department of Bioengineering, University of California, San Diego, CA, USA
| | - Christine B Chung
- Department of Radiology, University of California, San Diego, CA, USA.
- Department of Radiology, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA.
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Hu Y, Xu J, Zhou R, Xu Q, Sun S, Wang W, Chen H. The value of magnetic resonance ultrashort echo time imaging to evaluate non-calcified cartilage of the knee joint and its damage. Heliyon 2023; 9:e14120. [PMID: 36915568 PMCID: PMC10006742 DOI: 10.1016/j.heliyon.2023.e14120] [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: 02/10/2023] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 03/05/2023] Open
Abstract
Objectives To image knee osteochondral specimens using magnetic resonance (MR) ultrashort echo time imaging with pointwise encoding time reduction with radial acquisition combined fat suppression (PETRA-FS) sequence to determine whether it can reveal non-calcified cartilage, including the deep radial layer, and to assess its effectiveness in cartilage damage diagnosis. Materials and methods PETRA-FS imaging was performed on 58 osteochondral specimens of the lower femur and upper tibia to observe depth of cartilage damage, combined with histological results to observe signal intensity composition. Sensitivity, specificity, and reliability of PETRA-FS sequence for diagnosing cartilage damage were evaluated using histological results as the gold standard. Diagnostic efficacy was assessed using receiver operating characteristic (ROC) curve. Results MR ultrashort echo time imaging PETRA-FS sequence showed non-calcified cartilage, including tangential, transitional, and radial layers, which showed a high signal. PETRA-FS sequence showed 37 cases of cartilage damage and 21 cases of no damage among 58 specimens, kappa value of 0.75. Histological analysis of the 58 osteochondral specimens revealed 38 cases of cartilage injury and 20 cases of undamaged cartilage. Using histological results as the gold standard, PETRA-FS sequence had a sensitivity of 87.00%, specificity of 80.00%, kappa value of 0.81, and an area under the ROC curve (AUC) of 0.83 for cartilage injury diagnosis. Conclusion MR ultrashort echo time imaging PETRA-FS sequence can show non-calcified cartilage, including the deep radial layer (which cannot be shown by conventional MR), by exhibiting a high signal in knee osteo-chondral specimens. Thus, PETRA-FS sequences may have important diagnostic value for cartilage injury diagnosis.
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Affiliation(s)
- Yawen Hu
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Jun Xu
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Ruizhi Zhou
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Qi Xu
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Shiqing Sun
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Wenzhe Wang
- Department of Joint Surgery, The Affliated Hospital of Qingdao University Qingdao, 266003, China
| | - Haisong Chen
- Department of Radiology, The Affliated Hospital of Qingdao University Qingdao, 266003, China
- Corresponding author.
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Athertya JS, Akers J, Sedaghat S, Wei Z, Moazamian D, Dwek S, Thu M, Jang H. Detection of iron oxide nanoparticle (IONP)-labeled stem cells using quantitative ultrashort echo time imaging: a feasibility study. Quant Imaging Med Surg 2023; 13:585-597. [PMID: 36819276 PMCID: PMC9929408 DOI: 10.21037/qims-22-654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/17/2022] [Indexed: 01/12/2023]
Abstract
Background In this study, we investigated the feasibility of quantitative ultrashort echo time (qUTE) magnetic resonance (MR) imaging techniques in the detection and quantification of iron oxide nanoparticle (IONP)-labeled stem cells. Methods A stem cell phantom containing multiple layers of unlabeled or labeled stem cells with different densities was prepared. The phantom was imaged with quantitative UTE (qUTE) MR techniques [i.e., UTE-T1 mapping, UTE-T2* mapping, and UTE-based quantitative susceptibility mapping (UTE-QSM)] as well as with a clinical T2 mapping sequence on a 3T clinical MR system. For T1 mapping, a variable flip angle (VFA) method based on actual flip angle imaging (AFI) technique was utilized. For T2* mapping and UTE-QSM, multiple images with variable, interleaved echo times including UTE images and gradient recalled echo (GRE) images were used. For UTE-QSM, the phase information from the multi-echo images was utilized and processed using a QSM framework based on the morphology-enabled dipole inversion (MEDI) algorithm. The qUTE techniques were also evaluated in an ex vivo experiment with a mouse injected with IONP-labeled stem cells. Results In the phantom experiment, the parameters estimated with qUTE techniques showed high linearity with respect to the density of IONP-labeled stem cells (R2>0.99), while the clinical T2 parameter showed impaired linearity (R2=0.87). In the ex vivo mouse experiment, UTE-T2* mapping and UTE-QSM showed feasibility in the detection of injected stem cells with high contrast, whereas UTE-T1 and UTE-T2* showed limited detection. Overall, UTE-QSM demonstrated the best contrast of all, with other methods being subjected more to a confounding factor due to different magnetic susceptibilities of various types of neighboring tissues, which creates inhomogeneous contrast that behaves similar to IONP. Conclusions In this study, we evaluated the feasibility of a series of qUTE imaging techniques as well as conventional T2 mapping for the detection of IONP-labeled stem cells in vitro and ex vivo. UTE-QSM performed superior amongst other qUTE techniques as well as conventional T2 mapping in detecting stem cells with high contrast.
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Affiliation(s)
- Jiyo S. Athertya
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
| | | | - Sam Sedaghat
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
| | - Zhao Wei
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
| | - Sophia Dwek
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
| | - Mya Thu
- VisiCELL Medical Inc., San Diego, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, San Diego, CA, USA
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Lombardi AF, Guma M, Chung CB, Chang EY, Du J, Ma YJ. Ultrashort echo time magnetic resonance imaging of the osteochondral junction. NMR IN BIOMEDICINE 2023; 36:e4843. [PMID: 36264245 PMCID: PMC9845195 DOI: 10.1002/nbm.4843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 09/20/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Osteoarthritis is a common chronic degenerative disease that causes pain and disability with increasing incidence worldwide. The osteochondral junction is a dynamic region of the joint that is associated with the early development and progression of osteoarthritis. Despite the substantial advances achieved in the imaging of cartilage and application to osteoarthritis in recent years, the osteochondral junction has received limited attention. This is primarily related to technical limitations encountered with conventional MR sequences that are relatively insensitive to short T2 tissues and the rapid signal decay that characterizes these tissues. MR sequences with ultrashort echo time (UTE) are of great interest because they can provide images of high resolution and contrast in this region. Here, we briefly review the anatomy and function of cartilage, focusing on the osteochondral junction. We also review basic concepts and recent applications of UTE MR sequences focusing on the osteochondral junction.
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Affiliation(s)
- Alecio F. Lombardi
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | - Monica Guma
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
- Department of Medicine, University of California San Diego, CA, United States
| | - Christine B. Chung
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | - Eric Y. Chang
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | - Jiang Du
- Department of Radiology, University of California San Diego, CA, United States
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, CA, United States
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Lombardi AF, Ma Y, Jang H, Jerban S, Tang Q, Searleman AC, Meyer RS, Du J, Chang EY. AcidoCEST-UTE MRI Reveals an Acidic Microenvironment in Knee Osteoarthritis. Int J Mol Sci 2022; 23:4466. [PMID: 35457284 PMCID: PMC9027981 DOI: 10.3390/ijms23084466] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/08/2022] [Accepted: 04/13/2022] [Indexed: 02/01/2023] Open
Abstract
A relationship between an acidic pH in the joints, osteoarthritis (OA), and pain has been previously demonstrated. Acidosis Chemical Exchange Saturation Transfer (acidoCEST) indirectly measures the extracellular pH through the assessment of the exchange of protons between amide groups on iodinated contrast agents and bulk water. It is possible to estimate the extracellular pH in the osteoarthritic joint using acidoCEST MRI. However, conventional MR sequences cannot image deep layers of cartilage, meniscus, ligaments, and other musculoskeletal tissues that present with short echo time and fast signal decay. Ultrashort echo time (UTE) MRI, on the other hand, has been used successfully to image those joint tissues. Here, our goal is to compare the pH measured in the knee joints of volunteers without OA and patients with severe OA using acidoCEST-UTE MRI. Patients without knee OA and patients with severe OA were examined using acidoCEST-UTE MRI and the mean pH of cartilage, meniscus, and fluid was calculated. Additionally, the relationship between the pH measurements and the Knee Injury and Osteoarthritis Outcome Score (KOOS) was investigated. AcidoCEST-UTE MRI can detect significant differences in the pH of knee cartilage, meniscus, and fluid between joints without and with OA, with OA showing lower pH values. In addition, symptoms and knee-joint function become worse at lower pH measurements.
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Affiliation(s)
- Alecio F. Lombardi
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Yajun Ma
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Saeed Jerban
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Qingbo Tang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Adam C. Searleman
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Robert Scott Meyer
- Orthopaedic Surgery Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA;
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Eric Y. Chang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
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Afsahi AM, Sedaghat S, Moazamian D, Afsahi G, Athertya JS, Jang H, Ma YJ. Articular Cartilage Assessment Using Ultrashort Echo Time MRI: A Review. Front Endocrinol (Lausanne) 2022; 13:892961. [PMID: 35692400 PMCID: PMC9178905 DOI: 10.3389/fendo.2022.892961] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/14/2022] [Indexed: 01/05/2023] Open
Abstract
Articular cartilage is a major component of the human knee joint which may be affected by a variety of degenerative mechanisms associated with joint pathologies and/or the aging process. Ultrashort echo time (UTE) sequences with a TE less than 100 µs are capable of detecting signals from both fast- and slow-relaxing water protons in cartilage. This allows comprehensive evaluation of all the cartilage layers, especially for the short T2 layers which include the deep and calcified zones. Several ultrashort echo time (UTE) techniques have recently been developed for both morphological imaging and quantitative cartilage assessment. This review article summarizes the current catalog techniques based on UTE Magnetic Resonance Imaging (MRI) that have been utilized for such purposes in the human knee joint, such as T1, T2∗ , T1ρ, magnetization transfer (MT), double echo steady state (DESS), quantitative susceptibility mapping (QSM) and inversion recovery (IR). The contrast mechanisms as well as the advantages and disadvantages of these techniques are discussed.
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Affiliation(s)
- Amir Masoud Afsahi
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, United States
| | - Sam Sedaghat
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Dina Moazamian
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, United States
| | - Ghazaleh Afsahi
- Department of Biotechnology Research, BioSapien, San Diego, CA, United States
| | - Jiyo S. Athertya
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- *Correspondence: Ya-Jun Ma,
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