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Courtney C Hatcher, Amber T Collins, Sophia Y Kim, Lindsey C Michel, William C Mostertz, Sophia N Ziemian, Charles E Spritzer, Farshid Guilak, Louis E DeFrate, Amy L McNulty
Non-invasive techniques for quantifying early biochemical and biomechanical changes in articular cartilage may provide a means of more precisely assessing osteoarthritis (OA) progression. The goals of this study were to determine the relationship between T1rho magnetic resonance (MR) imaging relaxation times and changes in cartilage composition, cartilage mechanical properties, and synovial fluid biomarker levels and to demonstrate the application of T1rho imaging to evaluate cartilage composition in human subjects in vivo...
February 6, 2017: Journal of Biomechanics
H Shao, C Pauli, S Li, Y Ma, A S Tadros, E Y Chang, G Tang, J Du
PURPOSE: To investigate the effect of sample orientation on T1rho and T2 values of articular cartilage in histologically confirmed normal and abnormal regions using a whole-body 3T scanner. MATERIALS AND METHODS: Eight human cadaveric patellae were evaluated using a 2D CPMG sequence for T2 measurement as well as a 2D spin-locking prepared spiral sequence and a 3D magnetization-prepared angle-modulated partitioned-k-space spoiled gradient echo snapshots (3D MAPSS) sequence for T1rho measurement...
February 1, 2017: Osteoarthritis and Cartilage
Emre Unal, Ilkay Sedakat Idilman, Muşturay Karçaaltıncaba
New advances in liver magnetic resonance imaging (MRI) may enable diagnosis of unseen pathologies by conventional techniques. Normal T1 (550-620 ms for 1.5 T and 700-850 ms for 3 T), T2, T2* (>20 ms), T1rho (40-50 ms) mapping, proton density fat fraction (PDFF) (≤5%) and stiffness (2-3kPa) values can enable differentiation of a normal liver from chronic liver and diffuse diseases. Gd-EOB-DTPA can enable assessment of liver function by using postcontrast hepatobiliary phase or T1 reduction rate (normally above 60%)...
February 2017: Expert Review of Gastroenterology & Hepatology
Min A Yoon, Suk-Joo Hong, A Lan Im, Chang Ho Kang, Baek Hyun Kim, In Seong Kim
OBJECTIVE: To analyze subregional differences in T1rho (T1ρ) and T2 values and their correlation in asymptomatic knee cartilage, and to evaluate angular dependence with magic angles. MATERIALS AND METHODS: Six asymptomatic volunteers underwent knee MRI with T1ρ and T2 mapping. T1ρ and T2 values were measured by two radiologists independently, at nine subregions in the medial femoral condyle (MFC) cartilage, at angles of ± 0°, 15°, 35°, 55°, 75° respective to a vertical line (B0) bisecting the width of the distal femur, and at two locations in the patella...
November 2016: Korean Journal of Radiology: Official Journal of the Korean Radiological Society
Nan Zhou, Chen Chu, Xin Dou, Ming Li, Song Liu, Tingting Guo, Lijing Zhu, Baorui Liu, Weibo Chen, Jian He, Jing Yan, Zhengyang Zhou, Xiaofeng Yang
OBJECTIVE: The aim of the study was to confirm the feasibility of T1rho-weighted imaging to evaluate the dynamic changes of parotid glands in patients with nasopharyngeal carcinoma (NPC) undergoing intensity-modulated radiation therapy. METHODS: Twenty-six NPC patients (19 men; 7 women; mean [SD] age, 48.9 [13.4] years) underwent the following 3 serial T1rho-weighted imaging: within 2 weeks before radiotherapy (RT, pre-RT), 5 weeks after the beginning of RT (mid-RT), and 4 weeks after RT (post-RT)...
November 7, 2016: Journal of Computer Assisted Tomography
Chi-Man Koon, Xin Zhang, Weitian Chen, Eagle Siu Hong Chu, Clara Bik San Lau, Yì-Xiáng J Wáng
BACKGROUND: To explore black blood T1rho (T1ρ) liver imaging and investigate the earliest stage when biliary duct ligation (BDL) induced liver fibrosis can be diagnosed. METHODS: MR was performed at 3 Tesla. A T1ρ prepared 2D fast spin echo (FSE) sequence with acquisition of four spin lock times (TSLs: 1, 10, 30, and 50 msec) and spin-lock frequency of 500 Hz was applied. Inherent black blood effect of FSE and double inversion recovery (DIR) achieved blood signal suppression, and 3 axial sections per liver were obtained...
August 2016: Quantitative Imaging in Medicine and Surgery
Ya-Jun Ma, Hongda Shao, Jiang Du, Eric Y Chang
MRI biomarkers such as T2 , T2 * and T1rho have been widely used, but are confounded by the magic angle effect. The purpose of this study is to investigate the use of the two-dimensional ultrashort echo time magnetization transfer (UTE-MT) sequence for potential magic angle independent MR biomarkers. Magnetization transfer was investigated in cadaveric Achilles tendon samples using the UTE-MT sequence at five MT powers and five frequency offsets ranging from 2 to 50 kHz. The protocol was applied at five sample orientations ranging from 0 to 90° relative to the B0 field...
November 2016: NMR in Biomedicine
Hui Zhang, Qihua Yang, Taihui Yu, Xiaodong Chen, Jingwen Huang, Cui Tan, Biling Liang, Hua Guo
PURPOSE: To evaluate the value of T2 , T1 rho, and diffusion metrics in assessment of liver fibrosis in rats. MATERIALS AND METHODS: Liver fibrosis in a rat model (n = 72) was induced by injection of carbon tetrachloride (CCl4 ) at 3T. T2 , T1 rho, and diffusion parameters (apparent diffusion coefficient (ADC), Dtrue ) via spin echo (SE) diffusion-weighted imaging (DWI) and stimulated echo acquisition mode (STEAM) DWI with three diffusion times (DT: 80, 106, 186 msec) were obtained in surviving rats with hepatic fibrosis (n = 52) and controls (n = 8)...
August 16, 2016: Journal of Magnetic Resonance Imaging: JMRI
Jenna Le, Qi Peng, Karen Sperling
Osteoarthritis (OA) is a disease whose hallmark is the degeneration of articular cartilage. There is a worsening epidemic of OA in the United States today, with considerable economic costs. In order to develop more effective treatments for OA, noninvasive biomarkers that permit early diagnosis and treatment monitoring are necessary. T1rho and T2 mapping are two magnetic resonance imaging techniques that have shown great promise as noninvasive biomarkers of cartilage degeneration. Each of the two techniques is endowed with advantages and disadvantages: T1rho can discern earlier biochemical changes of OA than T2 mapping, while T2 mapping is more widely available and can be incorporated into existing imaging protocols in a more time-efficient manner than T1rho...
November 2016: Annals of the New York Academy of Sciences
Weitian Chen, Queenie Chan, Yì-Xiáng J Wáng
BACKGROUND: Liver fibrosis is a key feature in most chronic liver diseases. T1rho magnetic resonance imaging is a potentially important technique for noninvasive diagnosis, severity grading, and therapy monitoring of liver fibrosis. However, it remains challenging to perform robust T1rho quantification of liver on human subjects. One major reason is that the presence of rich blood signal in liver can cause artificially high T1rho measurement and makes T1rho quantification susceptible to motion...
April 2016: Quantitative Imaging in Medicine and Surgery
Min A Yoon, Suk-Joo Hong, Chang Ho Kang, Kyung-Sik Ahn, Baek Hyun Kim
PURPOSE: To assess regional variations of T1rho (T1ρ) and T2 rates within lumbar intervertebral discs and to evaluate the correlation of T1ρ and T2 rates in different disc regions with Pfirrmann grades of degeneration and morphologic changes. MATERIALS AND METHODS: We retrospectively evaluated 105 lumbar discs in 22 subjects who were examined at 3.0-T MRI. T1ρ and T2 relaxation rates (1/T1ρ and 1/T2) were measured in five segmented regions of discs: anterior annulus fibrosus (AF), anterior junction, nucleus pulposus (NP), posterior junction, and posterior AF...
September 2016: Magnetic Resonance Imaging
Feliks Kogan, Brian A Hargreaves, Garry E Gold
PURPOSE: To develop and optimize a multislice glycosaminoglycan (GAG) chemical exchange saturation transfer (GagCEST) sequence for volumetric imaging of articular cartilage, and to validate the sequence against T1ρ relaxation times in whole joint imaging of tibiotalar cartilage. METHODS: Ex vivo experiments were used to observe the effect of the number of partitions and shot TR on signal-to-noise ratio and measured GagCESTasym . GagCEST imaging of the entire tibiotalar joint was also performed on 10 healthy subjects...
March 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Shimpei Kondo, Takeshi Muneta, Yusuke Nakagawa, Hideyuki Koga, Toshifumi Watanabe, Kunikazu Tsuji, Shinichi Sotome, Atsushi Okawa, Shinji Kiuchi, Hideo Ono, Mitsuru Mizuno, Ichiro Sekiya
Transplantation of aggregates of synovial mesenchymal stem cells (MSCs) enhanced meniscus regeneration in rats. Anatomy and biological properties of the meniscus depend on animal species. To apply this technique clinically, it is valuable to investigate the use of animals genetically close to humans. We investigated whether transplantation of aggregates of autologous synovial MSCs promoted meniscal regeneration in aged primates. Chynomolgus primates between 12-13 years old were used. After the anterior halves of the medial menisci in both knees were removed, an average of 14 aggregates consisting of 250,000 synovial MSCs were transplanted onto the meniscus defect...
February 24, 2016: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
Won C Bae, Thumanoon Ruangchaijatuporn, Eric Y Chang, Reni Biswas, Jiang Du, Sheronda Statum, Christine B Chung
OBJECTIVE: To evaluate pathology of the triangular fibrocartilage complex (TFCC) using high-resolution morphologic magnetic resonance (MR) imaging, and compare with quantitative MR and biomechanical properties. MATERIALS AND METHODS: Five cadaveric wrists (22-70 years) were imaged at 3 T using morphologic (proton density weighted spin echo, PD FS, and 3D spoiled gradient echo, 3D SPGR) and quantitative MR sequences to determine T2 and T1rho properties. In eight geographic regions, morphology of TFC disc and laminae were evaluated for pathology and quantitative MR values...
April 2016: Skeletal Radiology
Kanji Osaki, Ken Okazaki, Yukihisa Takayama, Hirokazu Matsubara, Umito Kuwashima, Koji Murakami, Toshio Doi, Yoshio Matsuo, Hiroshi Honda, Yukihide Iwamoto
BACKGROUND: Patients with anterior cruciate ligament (ACL)-injured knees are at an increased risk of posttraumatic osteoarthritis (OA). OA changes secondary to ACL injuries have many variations, and when and where early cartilage degenerative change begins has not yet been established. PURPOSE: To characterize the location of cartilage degeneration after ACL injury associated with time since injury using T1rho (T1ρ) mapping. STUDY DESIGN: Cross-sectional study; Level of evidence, 3...
May 2015: Orthopaedic Journal of Sports Medicine
Julie L Calahan, Stephanie C Azali, Eric J Munson, Karthik Nagapudi
Intimate phase mixing between the drug and the polymer is considered a prerequisite to achieve good physical stability for amorphous solid dispersions. In this article, spray dried amorphous dispersions (ASDs) of AMG 517 and HPMC-as were studied by differential scanning calorimetry (DSC), solid-state NMR (SSNMR), and solution calorimetry. DSC analysis showed a weakly asymmetric (ΔTg ≈ 13.5) system with a single glass transition for blends of different compositions indicating phase mixing. The Tg-composition data was modeled using the BKCV equation to accommodate the observed negative deviation from ideality...
November 2, 2015: Molecular Pharmaceutics
Weitian Chen
The spin-lattice relaxation time constant in rotating frame (T1rho) is useful for assessment of the properties of macromolecular environment inside tissue. Quantification of T1rho is found promising in various clinical applications. However, T1rho imaging is prone to image artifacts and quantification errors, which remains one of the greatest challenges to adopt this technique in routine clinical practice. The conventional continuous wave spin-lock is susceptible to B1 radiofrequency (RF) and B0 field inhomogeneity, which appears as banding artifacts in acquired images...
August 2015: Quantitative Imaging in Medicine and Surgery
Kenyu Iwasaki, Monica Tafur, Eric Y Chang, Sheronda Statum, Reni Biswas, Betty Tran, Won C Bae, Jiang Du, Graeme M Bydder, Christine B Chung
OBJECTIVE: This study aimed to implement qualitative and quantitative magnetic resonance sequences for the evaluation of labral pathology. METHODS: Six glenoid labra were dissected, and the anterior and posterior portions were divided into normal, mildly degenerated, or severely degenerated groups using gross and magnetic resonance findings. Qualitative evaluation was performed using T1-weighted, proton density-weighted, spoiled gradient echo and ultrashort echo time (UTE) sequences...
November 2015: Journal of Computer Assisted Tomography
Bernd Bittersohl, Harish S Hosalkar, Tobias Hesper, Carl Johan Tiderius, Christoph Zilkens, Rüdiger Krauspe
Symptomatic femoroacetabular impingement (FAI) is now a known precursor of early osteoarthritis (OA) of the hip. In terms of clinical intervention, the decision between joint preservation and joint replacement hinges on the severity of articular cartilage degeneration. The exact threshold during the course of disease progression when the cartilage damage is irreparable remains elusive. The intention behind radiographic imaging is to accurately identify the morphology of osseous structural abnormalities and to accurately characterize the chondrolabral damage as much as possible...
2015: Frontiers in Surgery
Roshan P Shah, Jeffrey B Stambough, Matthew Fenty, Robert L Mauck, John D Kelly, Ravinder Reddy, Fotios P Tjoumakaris
Viscosupplementation may affect cartilage. Changes in T1rho magnetic resonance imaging (MRI) relaxation times correlate with proteoglycan changes in cartilage. The authors hypothesized that T1rho MRI will show an improvement in proteoglycan content at 6 weeks and 3 months after viscosupplementation and that this improvement will correlate with functional outcome scores. Ten patients (mean age, 56 years; Kellgren-Lawrence grade 1 or 2) underwent T1rho MRI at baseline, 6 weeks, and 3 months after viscosupplementation...
July 1, 2015: Orthopedics
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