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Shin SH, Moazamian D, Suprana A, Zeng C, Athertya JS, Carl M, Ma Y, Jang H, Du J. Yet more evidence that non-aqueous myelin lipids can be directly imaged with ultrashort echo time (UTE) MRI on a clinical 3T scanner: a lyophilized red blood cell membrane lipid study. Neuroimage 2024; 296:120666. [PMID: 38830440 DOI: 10.1016/j.neuroimage.2024.120666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 05/16/2024] [Accepted: 05/31/2024] [Indexed: 06/05/2024] Open
Abstract
Direct imaging of semi-solid lipids, such as myelin, is of great interest as a noninvasive biomarker of neurodegenerative diseases. Yet, the short T2 relaxation times of semi-solid lipid protons hamper direct detection through conventional magnetic resonance imaging (MRI) pulse sequences. In this study, we examined whether a three-dimensional ultrashort echo time (3D UTE) sequence can directly acquire signals from membrane lipids. Membrane lipids from red blood cells (RBC) were collected from commercially available blood as a general model of the myelin lipid bilayer and subjected to D2O exchange and freeze-drying for complete water removal. Sufficiently high MR signals were detected with the 3D UTE sequence, which showed an ultrashort T2* of ∼77-271 µs and a short T1 of ∼189 ms for semi-solid RBC membrane lipids. These measurements can guide designing UTE-based sequences for direct in vivo imaging of membrane lipids.
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Affiliation(s)
- Soo Hyun Shin
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Arya Suprana
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
| | - Chun Zeng
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Jiyo S Athertya
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | | | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Shu Chien-Gene Lay Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, CA, USA.
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Jerban S, Moazamian D, Mohammadi HS, Ma Y, Jang H, Namiranian B, Shin SH, Alenezi S, Shah SB, Chung CB, Chang EY, Du J. More accurate trabecular bone imaging using UTE MRI at the resonance frequency of fat. Bone 2024; 184:117096. [PMID: 38631596 DOI: 10.1016/j.bone.2024.117096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/18/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
High-resolution magnetic resonance imaging (HR-MRI) has been increasingly used to assess the trabecular bone structure. High susceptibility at the marrow/bone interface may significantly reduce the marrow's apparent transverse relaxation time (T2*), overestimating trabecular bone thickness. Ultrashort echo time MRI (UTE-MRI) can minimize the signal loss caused by susceptibility-induced T2* shortening. However, UTE-MRI is sensitive to chemical shift artifacts, which manifest as spatial blurring and ringing artifacts partially due to non-Cartesian sampling. In this study, we proposed UTE-MRI at the resonance frequency of fat to minimize marrow-related chemical shift artifacts and the overestimation of trabecular thickness. Cubes of trabecular bone from six donors (75 ± 4 years old) were scanned using a 3 T clinical scanner at the resonance frequencies of fat and water, respectively, using 3D UTE sequences with five TEs (0.032, 1.1, 2.2, 3.3, and 4.4 ms) and a clinical 3D gradient echo (GRE) sequence at 0.2 × 0.2 × 0.4 mm3 voxel size. Trabecular bone thickness was measured in 30 regions of interest (ROIs) per sample. MRI results were compared with thicknesses obtained from micro-computed tomography (μCT) at 50 μm3 voxel size. Linear regression models were used to calculate the coefficient of determination between MRI- and μCT-based trabecular thickness. All MRI-based trabecular thicknesses showed significant correlations with μCT measurements. The correlations were higher (examined with paired Student's t-test, P < 0.01) for 3D UTE images performed at the fat frequency (R2 = 0.59-0.74, P < 0.01) than those at the water frequency (R2 = 0.18-0.52, P < 0.01) and clinical GRE images (R2 = 0.39-0.47, P < 0.01). Significantly reduced correlations were observed with longer TEs. This study highlighted the feasibility of UTE-MRI at the fat frequency for a more accurate assessment of trabecular bone thickness.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA.
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | | | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Behnam Namiranian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Soo Hyun Shin
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Salem Alenezi
- Research and Laboratories Sector, Saudi Food and Drug Authority, Riyadh, Saudi Arabia
| | - Sameer B Shah
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA; Orthopaedic Research, University of California, San Diego, La Jolla, CA, USA
| | - Christine B Chung
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA.
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Slawig A, Rothe M, Deistung A, Bohndorf K, Brill R, Graf S, Weng AM, Wohlgemuth WA, Gussew A. Ultra-short echo time (UTE) MR imaging: A brief review on technical considerations and clinical applications. ROFO-FORTSCHR RONTG 2024; 196:671-681. [PMID: 37995735 DOI: 10.1055/a-2193-1379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Affiliation(s)
- Anne Slawig
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
| | - Maik Rothe
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
| | - Andreas Deistung
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
| | - Klaus Bohndorf
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
| | - Richard Brill
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
| | - Simon Graf
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
| | - Andreas Max Weng
- Department of Diagnostic and Interventional Radiology, University Hospital Wurzburg, Wurzburg, Germany
| | - Walter A Wohlgemuth
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
| | - Alexander Gussew
- University Clinic and Outpatient Clinic for Radiology, University Hospital Halle, Germany
- Halle MR Imaging Core Facility, Medical faculty, Martin Luther University Halle Wittenberg, Halle, Germany
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Wáng YXJ. Cartilaginous endplate coverage of developmental Schmorl's node and the relevance of this in Schmorl's node etiology-based classification. Quant Imaging Med Surg 2024; 14:4288-4303. [PMID: 38846309 PMCID: PMC11151241 DOI: 10.21037/qims-24-335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 04/22/2024] [Indexed: 06/09/2024]
Affiliation(s)
- Yì Xiáng J Wáng
- Department of Imaging and Interventional Radiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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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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Athertya JS, Lo J, Chen X, Shin SH, Malhi BS, Jerban S, Ji Y, Sedaghat S, Yoshioka H, Du J, Guma M, Chang EY, Ma Y. High contrast cartilaginous endplate imaging in spine using three dimensional dual-inversion recovery prepared ultrashort echo time (3D DIR-UTE) sequence. Skeletal Radiol 2024; 53:881-890. [PMID: 37935923 PMCID: PMC10973042 DOI: 10.1007/s00256-023-04503-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 10/14/2023] [Accepted: 10/29/2023] [Indexed: 11/09/2023]
Abstract
PURPOSE To investigate the feasibility and application of a novel imaging technique, a three-dimensional dual adiabatic inversion recovery prepared ultrashort echo time (3D DIR-UTE) sequence, for high contrast assessment of cartilaginous endplate (CEP) imaging with head-to-head comparisons between other UTE imaging techniques. METHOD The DIR-UTE sequence employs two narrow-band adiabatic full passage (AFP) pulses to suppress signals from long T2 water (e.g., nucleus pulposus (NP)) and bone marrow fat (BMF) independently, followed by multispoke UTE acquisition to detect signals from the CEP with short T2 relaxation times. The DIR-UTE sequence, in addition to three other UTE sequences namely, an IR-prepared and fat-saturated UTE (IR-FS-UTE), a T1-weighted and fat-saturated UTE sequence (T1w-FS-UTE), and a fat-saturated UTE (FS-UTE) was used for MR imaging on a 3 T scanner to image six asymptomatic volunteers, six patients with low back pain, as well as a human cadaveric specimen. The contrast-to-noise ratio of the CEP relative to the adjacent structures-specifically the NP and BMF-was then compared from the acquired images across the different UTE sequences. RESULTS For asymptomatic volunteers, the DIR-UTE sequence showed significantly higher contrast-to-noise ratio values between the CEP and BMF (CNRCEP-BMF) (19.9 ± 3.0) and between the CEP and NP (CNRCEP-NP) (23.1 ± 1.7) compared to IR-FS-UTE (CNRCEP-BMF: 17.3 ± 1.2 and CNRCEP-NP: 19.1 ± 1.8), T1w-FS-UTE (CNRCEP-BMF: 9.0 ± 2.7 and CNRCEP-NP: 10.4 ± 3.5), and FS-UTE (CNRCEP-BMF: 7.7 ± 2.2 and CNRCEP-NP: 5.8 ± 2.4) for asymptomatic volunteers (all P-values < 0.001). For the spine sample and patients with low back pain, the DIR-UTE technique detected abnormalities such as irregularities and focal defects in the CEP regions. CONCLUSION The 3D DIR-UTE sequence is able to provide high-contrast volumetric CEP imaging for human spines on a clinical 3 T scanner.
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Affiliation(s)
- Jiyo S Athertya
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - James Lo
- Department of Radiology, University of California San Diego, San Diego, CA, USA
- Department of Bioengineering, University of California San Diego, San Diego, CA, USA
| | - Xiaojun Chen
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Soo Hyun Shin
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | | | - Saeed Jerban
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Yang Ji
- 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
| | - Hiroshi Yoshioka
- Department of Radiological Sciences, University of California Irvine, Irvine, CA, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, CA, USA
- Department of Bioengineering, University of California San Diego, San Diego, CA, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Monica Guma
- Department of Medicine, University of California San Diego, San Diego, CA, USA
- Medicine Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, San Diego, CA, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California San Diego, San Diego, CA, USA.
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Shi M, Xiong W, Feng J, Wu L, Yang J, Lu Y, Lu X, Fan Q, Nie H, Dai Y, Yan C, Tian Y, Shen Z. Kilogram scale facile synthesis and systematic characterization of a Gd-macrochelate as T 1-weighted magnetic resonance imaging contrast agent. J Nanobiotechnology 2024; 22:162. [PMID: 38594700 PMCID: PMC11005285 DOI: 10.1186/s12951-024-02394-8] [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: 11/04/2023] [Accepted: 03/11/2024] [Indexed: 04/11/2024] Open
Abstract
To overcome the problems of commercial magnetic resonance imaging (MRI) contrast agents (CAs) (i.e., small molecule Gd chelates), we have proposed a new concept of Gd macrochelates based on the coordination of Gd3+ and macromolecules, e.g., poly(acrylic acid) (PAA). To further decrease the r2/r1 ratio of the reported Gd macrochelates that is an important factor for T1 imaging, in this study, a superior macromolecule hydrolyzed polymaleic anhydride (HPMA) was found to coordinate Gd3+. The synthesis conditions were optimized and the generated Gd-HPMA macrochelate was systematically characterized. The obtained Gd-HPMA29 synthesized in a 100 L of reactor has a r1 value of 16.35 mM-1 s-1 and r2/r1 ratio of 2.05 at 7.0 T, a high Gd yield of 92.7% and a high product weight (1074 g), which demonstrates the feasibility of kilogram scale facile synthesis. After optimization of excipients and sterilization at a high temperature, the obtained Gd-HPMA30 formulation has a pH value of 7.97, osmolality of 691 mOsmol/kg water, density of 1.145 g/mL, and viscosity of 2.2 cP at 20 ℃ or 1.8 cP at 37 ℃, which meet all specifications and physicochemical criteria for clinical injections indicating the immense potential for clinical applications.
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Affiliation(s)
- Meng Shi
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Wei Xiong
- Medical Imaging Center, Nanfang Hospital, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China.
| | - Jie Feng
- Medical Imaging Center, Nanfang Hospital, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Lihe Wu
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Jing Yang
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Yudie Lu
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Xuanyi Lu
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Qingdeng Fan
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China
| | - Hemin Nie
- Department of Biomedical Sciences, College of Biology, Hunan University, 52 Tianmu Road, Yuelu, Changsha, 410082, Hunan, China
| | - Yunlu Dai
- Faculty of Health Sciences and MoE Frontiers Science Center for Precision Oncology, University of Macau, Macau SAR, 999078, China
| | - Chenggong Yan
- Medical Imaging Center, Nanfang Hospital, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China.
| | - Ye Tian
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China.
| | - Zheyu Shen
- School of Biomedical Engineering, Southern Medical University, 1023 Shatai South Road, Baiyun, Guangzhou, 510515, Guangdong, China.
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Jerban S, Moazamian D, Ma Y, Afsahi AM, Dwek S, Athertya J, Malhi B, Jang H, Woods G, Chung CB, Du J, Chang EY. Fast dual-echo estimation of apparent long T2 fraction using ultrashort echo time magnetic resonance imaging in tibialis tendons and its osteoporosis-related differences in women. Quant Imaging Med Surg 2024; 14:3146-3156. [PMID: 38617168 PMCID: PMC11007502 DOI: 10.21037/qims-23-1341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/09/2024] [Indexed: 04/16/2024]
Abstract
Background Tendon and bone comprise a critical interrelating unit. Bone loss, including that seen with osteopenia (OPe) or osteoporosis (OPo), may be associated with a reduction in tendon quality, though this remains incompletely investigated. Clinical magnetic resonance imaging (MRI) sequences cannot directly detect signals from tendons because of the very short T2. Clinical MRI may detect high-graded abnormalities by changes in the adjacent structures like bone. However, ultrashort echo time MRI (UTE-MRI) can capture high signals from all tendons. To determine if the long T2 fraction, as measured by a dual-echo UTE-MRI sequence, is a sensitive quantitative technique to the age- and bone-loss-related changes of the lower leg tendons. Methods This is a cross-sectional study conducted between January 2018 to February 2020 in the lower legs of 14 female patients with OPe [72±6 years old, body mass index (BMI) =25.8±6.2 kg/m2] and 31 female patients with OPo (73±6 years old, BMI=22.0±3.8 kg/m2), as well as 30 female subjects with normal bone (Normal, 35±18 years old, BMI =23.2±4.3 kg/m2), were imaged on a 3T clinical scanner using a dual-echo 3D Cones UTE sequence. We defined the apparent long T2 signal fraction (aFrac-LongT2) of tendons as the ratio between the signal at the second echo time (TE =2.2 ms) to the UTE signal. The average aFrac-LongT2 and the cross-sectional area were calculated for the anterior tibialis tendons (ATTs) and the posterior tibialis tendons (PTTs). The Kruskal-Wallis rank test was used to compare the differences in aFrac-LongT2 and the cross-sectional area of the tendons between the groups. Results The aFrac-LongT2 of the ATTs and PTTs were significantly higher in the OPo group compared with the Normal group (22.2% and 34.8% in the ATT and PTT, respectively, P<0.01). The cross-sectional area in the ATTs was significantly higher for the OPo group than in the Normal group (Normal/OPo difference was 28.7, P<0.01). Such a difference for PTTs did not reach the significance level. Mean aFrac-LongT2 and cross-sectional area in the OPe group were higher than the Normal group and lower than the OPo group. However, the differences did not show statistical significance, likely due to the higher BMI in the OPe group. Conclusions Dual-echo UTE-MRI is a rapid quantification technique, and aFrac-LongT2 values showed significant differences in tendons between Normal and OPo patients.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Amir Masoud Afsahi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Sophia Dwek
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Jiyo Athertya
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Bhavsimran Malhi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Gina Woods
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Christine B. Chung
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
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9
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Li YX, Liang XL, Liu J, Ma YJ. Assessment of Osteoporosis at the Lumbar Spine Using Ultrashort Echo Time Magnetization Transfer (UTE-MT) MRI. J Magn Reson Imaging 2024; 59:1285-1298. [PMID: 37470693 PMCID: PMC10799192 DOI: 10.1002/jmri.28910] [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: 03/10/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023] Open
Abstract
BACKGROUND Bone collagen-matrix contributes to the mechanical properties of bone by imparting tensile strength and elasticity, which can be indirectly quantified by ultrashort echo time magnetization transfer ratio (UTE-MTR) to assess osteoporosis. PURPOSE To evaluate osteoporosis at the human lumbar spine using UTE-MTR. STUDY TYPE Prospective. POPULATION One hundred forty-eight-volunteers (age-range, 50-85; females, N = 90), including 81-normal bone density, 35-osteopenic, and 32-osteoporotic subjects. Ten additional healthy volunteers were recruited to study the intrasession reproducibility of the UTE-MT. FIELD STRENGTH/SEQUENCE 3T/UTE-MT, short repetition-time adiabatic inversion recovery prepared UTE (STAIR-UTE), and iterative decomposition of water-and-fat with echo-asymmetry and least-squares estimation (IDEAL-IQ). ASSESSMENT Fracture risk was calculated using Fracture-Risk-Assessment-Tool (FRAX). Region-of-interests (ROIs) were delineated on the trabecular area in the maps of bone-mineral-density, UTE-MTR, collagen-bound water proton-fraction (CBWPF), and bone-marrow fat fraction (BMFF). STATISTICAL TESTS Linear-regression and Bland-Altman analysis were performed to assess the reproducibility of UTE-MTR measurements in the different scans. UTE-MTR and BMFF were correlated with bone-mineral-density using Pearson's regression and with FRAX scores using nonlinear regression. The abilities of UTE-MTR, CBWPF, and BMFF to discriminate between the three patient subgroups were evaluated using receiver-operator-characteristic (ROC) analysis and area-under-the-curve (AUC). Decision-curve-analysis (DCA) and clinical-impact curves were used to evaluate the value of UTE-MTR in clinical diagnosis. The DeLong test was used to compare the ROC curves. P-value <0.05 was considered statistically significant. RESULTS Excellent reproducibility was obtained for the UTE-MT measurements. UTE-MTR strongly correlated with bone-mineral-density (r = 0.76) and FRAX scores (r = -0.77). UTE-MTR exhibited higher AUCs (≥0.723) than BMFF, indicating its superior ability to distinguish between the three patient subgroups. The DCA and clinical-impact curves confirmed the diagnostic value of UTE-MTR. UTE-MTR and CBWPF showed similar performance in correlation with bone-mineral-density and cohort classification. DATA CONCLUSION UTE-MTR strongly correlates with bone-mineral-density and FRAX and shows great potential in distinguishing between normal, osteopenic, and osteoporotic subjects. EVIDENCE LEVEL 1 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Yu-Xuan Li
- Shanxi Medical University, Taiyuan, China
| | - Xiao-Ling Liang
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
| | - Jin Liu
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
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Jerban S, Jang H, Chang EY, Bukata S, Du J, Chung CB. Bone Biomarkers Based on Magnetic Resonance Imaging. Semin Musculoskelet Radiol 2024; 28:62-77. [PMID: 38330971 DOI: 10.1055/s-0043-1776431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
Magnetic resonance imaging (MRI) is increasingly used to evaluate the microstructural and compositional properties of bone. MRI-based biomarkers can characterize all major compartments of bone: organic, water, fat, and mineral components. However, with a short apparent spin-spin relaxation time (T2*), bone is invisible to conventional MRI sequences that use long echo times. To address this shortcoming, ultrashort echo time MRI sequences have been developed to provide direct imaging of bone and establish a set of MRI-based biomarkers sensitive to the structural and compositional changes of bone. This review article describes the MRI-based bone biomarkers representing total water, pore water, bound water, fat fraction, macromolecular fraction in the organic matrix, and surrogates for mineral density. MRI-based morphological bone imaging techniques are also briefly described.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, California
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, California
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, La Jolla, California
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Susan Bukata
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, California
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, California
- Department of Bioengineering, University of California, San Diego, La Jolla, California
| | - Christine B Chung
- Department of Radiology, University of California, San Diego, La Jolla, California
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, California
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Malhi BS, Moazamian D, Shin SH, Athertya JS, Silva L, Jerban S, Jang H, Chang E, Ma Y, Carl M, Du J. Bi-Exponential 3D UTE-T1ρ Relaxation Mapping of Ex Vivo Human Knee Patellar Tendon at 3T. Bioengineering (Basel) 2024; 11:66. [PMID: 38247943 PMCID: PMC10813751 DOI: 10.3390/bioengineering11010066] [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: 11/27/2023] [Revised: 12/30/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Introduction: The objective of this study was to assess the bi-exponential relaxation times and fractions of the short and long components of the human patellar tendon ex vivo using three-dimensional ultrashort echo time T1ρ (3D UTE-T1ρ) imaging. Materials and Methods: Five cadaveric human knee specimens were scanned using a 3D UTE-T1ρ imaging sequence on a 3T MR scanner. A series of 3D UTE-T1ρ images were acquired and fitted using single-component and bi-component models. Single-component exponential fitting was performed to measure the UTE-T1ρ value of the patellar tendon. Bi-component analysis was performed to measure the short and long UTE-T1ρ values and fractions. Results: The single-component analysis showed a mean single-component UTE-T1ρ value of 8.4 ± 1.7 ms for the five knee patellar tendon samples. Improved fitting was achieved with bi-component analysis, which showed a mean short UTE-T1ρ value of 5.5 ± 0.8 ms with a fraction of 77.6 ± 4.8%, and a mean long UTE-T1ρ value of 27.4 ± 3.8 ms with a fraction of 22.4 ± 4.8%. Conclusion: The 3D UTE-T1ρ sequence can detect the single- and bi-exponential decay in the patellar tendon. Bi-component fitting was superior to single-component fitting.
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Affiliation(s)
- Bhavsimran Singh Malhi
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Dina Moazamian
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Soo Hyun Shin
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Jiyo S. Athertya
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Livia Silva
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Saeed Jerban
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Hyungseok Jang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Eric Chang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Yajun Ma
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Michael Carl
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- General Electric Health Care, San Diego, CA 92037, USA
| | - Jiang Du
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
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Cui L, McWalter EJ, Moran G, Venugopal N. Design and development of a novel flexible ultra-short echo time (FUSE) sequence. Magn Reson Med 2023; 90:1905-1918. [PMID: 37392415 DOI: 10.1002/mrm.29784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/28/2023] [Accepted: 06/13/2023] [Indexed: 07/03/2023]
Abstract
PURPOSE To present the validation of a new Flexible Ultra-Short Echo time (FUSE) pulse sequence using a short-T2 phantom. METHODS FUSE was developed to include a range of RF excitation pulses, trajectories, dimensionalities, and long-T2 suppression techniques, enabling real-time interchangeability of acquisition parameters. Additionally, we developed an improved 3D deblurring algorithm to correct for off-resonance artifacts. Several experiments were conducted to validate the efficacy of FUSE, by comparing different approaches for off-resonance artifact correction, variations in RF pulse and trajectory combinations, and long-T2 suppression techniques. All scans were performed on a 3 T system using an in-house short-T2 phantom. The evaluation of results included qualitative comparisons and quantitative assessments of the SNR and contrast-to-noise ratio. RESULTS Using the capabilities of FUSE, we demonstrated that we could combine a shorter readout duration with our improved deblurring algorithm to effectively reduce off-resonance artifacts. Among the different RF and trajectory combinations, the spiral trajectory with the regular half-inc pulse achieves the highest SNRs. The dual-echo subtraction technique delivers better short-T2 contrast and superior suppression of water and agar signals, whereas the off-resonance saturation method successfully suppresses water and lipid signals simultaneously. CONCLUSION In this work, we have validated the use of our new FUSE sequence using a short T2 phantom, demonstrating that multiple UTE acquisitions can be achieved within a single sequence. This new sequence may be useful for acquiring improved UTE images and the development of UTE imaging protocols.
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Affiliation(s)
- Lumeng Cui
- Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Emily J McWalter
- Department of Mechanical Engineering and Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Gerald Moran
- Siemens Healthcare Limited, Oakville, Ontario, Canada
| | - Niranjan Venugopal
- Department of Radiology, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, Canada
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13
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Jerban S, Afsahi AM, Ma Y, Moazamian D, Statum S, Lombardi AF, Kakos L, Dorthe E, Dlima D, Du J, Chung CB, Chang EY. Correlations between elastic modulus and ultrashort echo time (UTE) adiabatic T1ρ relaxation time (UTE-Adiab-T1ρ) in Achilles tendons and entheses. J Biomech 2023; 160:111825. [PMID: 37856976 PMCID: PMC10991081 DOI: 10.1016/j.jbiomech.2023.111825] [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: 04/11/2023] [Revised: 09/27/2023] [Accepted: 10/03/2023] [Indexed: 10/21/2023]
Abstract
Patients with psoriatic arthritis commonly have abnormalities of their entheses, which are the connections between tendons and bone. There are shortcomings with the use of conventional magnetic resonance imaging (MRI) sequences for the evaluation of entheses and tendons, whereas ultrashort echo time (UTE) sequences are superior for the detection of high signals, and can also be used for non-invasive quantitative assessments of these structures. The combination of UTE-MRI with an adiabatic-T1ρ preparation (UTE-Adiab-T1ρ) allows for reliable assessment of entheses and tendons with decreased susceptibility to detrimental magic angle effects. This study aimed to investigate the relationship between quantitative UTE-MRI measures and the biomechanical properties of Achilles tendons and entheses. In total, 28 tendon-enthesis sections were harvested from 11 fresh-frozen human cadaveric foot-ankle specimens (52 ± years old). Tendon-enthesis sections were scanned using the UTE-Adiab-T1ρ and UTE-T1 sequences on a clinical 3 T scanner. MRI-based measures and indentation tests were performed on the enthesis, transitional, and tensile tendon zones of the specimens. Hayes' elastic modulus showed significant inverse correlations (Spearman's) with UTE-Adiab-T1ρ in all zones (R= - 0.46, - 0.54, and - 0.61 in enthesis, transition, and tensile tendon zones, respectively). Oliver-Pharr's elastic modulus showed significant inverse correlations with UTE-Adiab-T1ρ in transition (R= - 0.52) and tensile tendon zone (R=- 0.60). UTE-T1 did not show significant correlations with the elastic modulus. UTE-MRI and elastic modulus were significantly lower in the tensile tendon compared with the enthesis regions This study highlights the potential of the UTE-Adiab-T1ρ technique for the non-invasive evaluation of tendons and enthuses.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA; Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA.
| | - Amir Masoud Afsahi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Sheronda Statum
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Alecio F Lombardi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Lena Kakos
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Erik Dorthe
- Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Daryll Dlima
- Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Christine B Chung
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA; Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA.
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Jang H, Athertya J, Jerban S, Ma Y, Lombardi AF, Chung CB, Chang EY, Du J. Correction of B 0 and linear eddy currents: Impact on morphological and quantitative ultrashort echo time double echo steady state (UTE-DESS) imaging. NMR IN BIOMEDICINE 2023; 36:e4939. [PMID: 36965076 PMCID: PMC10518369 DOI: 10.1002/nbm.4939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 05/10/2023]
Abstract
The purpose of the current study was to investigate the effects of B0 and linear eddy currents on ultrashort echo time double echo steady state (UTE-DESS) imaging and to determine whether eddy current correction (ECC) effectively resolves imaging artifacts caused by eddy currents. 3D UTE-DESS sequences based on either projection radial or spiral cones trajectories were implemented on a 3-T clinical MR scanner. An off-isocentered thin-slice excitation approach was used to measure eddy currents. The measurements were repeated four times using two sets of tested gradient waveforms with opposite polarities and two different slice locations to measure B0 and linear eddy currents simultaneously. Computer simulation was performed to investigate the eddy current effect. Finally, a phantom experiment, an ex vivo experiment with human synovium and ankle samples, and an in vivo experiment with human knee joints, were performed to demonstrate the effects of eddy currents and ECC in UTE-DESS imaging. In a computer simulation, the two echoes (S+ and S-) in UTE-DESS imaging exhibited strong distortion at different orientations in the presence of B0 and linear eddy currents, resulting in both image degradation as well as misalignment of pixel location between the two echoes. The same phenomenon was observed in the phantom, ex vivo, and in vivo experiments, where the presence of eddy currents degraded S+, S-, echo subtraction images, and T2 maps. The implementation of ECC dramatically improved both the image quality and image registration between the S+ and S- echoes. It was concluded that ECC is crucial for reliable morphological and quantitative UTE-DESS imaging.
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Affiliation(s)
- Hyungseok Jang
- Department of Radiology, University of California, San Diego, USA
| | - Jiyo Athertya
- Department of Radiology, University of California, San Diego, USA
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, USA
| | | | - Christine B Chung
- Department of Radiology, University of California, San Diego, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, USA
- Department of Bioengineering, University of California, San Diego, USA
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