Jari Rautiainen^1,2, Mikko J. Nissi^1,2, Elli-Noora Salo³, Harri Kokkonen^2,4, Shalom Michaeli⁵, Silvi Mangia⁵, Olli Gröhn⁶, Juha Töyräs^2,4, and Miika T. Nieminen^1,3
1Medical Research Center Oulu and Department of Diagnostic Radiology, University of Oulu, Oulu, Finland, ²Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, ³Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland, ⁴Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland, ⁵Center for Magnetic Resonance Research, University of Minnesota, MN, United States, ⁶Department of Neurobiology, A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland

Aging of cartilage results in accumulation of advanced glycation end products (AGEs), most notably collagen cross-links in cartilage. Increased cross-linking of the collagens makes cartilage more stiff and brittle. In this study, sensitivity of quantitative MRI parameters to artificial collagen cross-linking induced by L-threose in bovine articular cartilage was evaluated. Artificial cross-linking detectably changed the biophysical properties of cartilage which were also detected with MRI parameters. While T2 and dGEMRIC responded to the treatment as expected, T1ρ relaxation time constants showed unexpected increase, possibly attributed to an increased cross-linked fraction characterized by the slow motion or blocking of exchange-mediated relaxation.

Jose G Raya¹, Ignacio Rossi¹, Oran Kennedy¹, Natalie Danna¹, Bryan Beutel¹, You Jin Lee¹, and Thorsten Kirsch^1
1NYU Langone Medical Center, New York, NY, United States

We validate DTI of articular cartilage in an animal model of posttraumatic osteoarthritis (PTOA). Eight New Zeeland white rabbits underwent anterior cruciate ligament transection (ACLT) on one of the hindlimbs and sham surgery in the contralateral limb. Rabbits were scarified at 4 (n=4) and 8 weeks (n=4) after surgery. Both joints underwent MRI (PD-weighted and DTI), micro-CT and histology with safranin O. We observe a trend of increased MD in the ACLT joints compared to the sham that was significant at 8 weeks. Changes in MD correlated with areas of PG loss in histology, that only show changes on PG

Martijn A Cloos¹, Leeor Alon¹, Christian Geppert², Daniel K Sodickson¹, and Riccardo Lattanzi^1
1Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States, ²Siemens AG Healthcare, Erlangen, Germany

Biochemical assessment is critical for early detection and staging of hip articular cartilage damage, as well as to predict risk for progression. We employed the principles of magnetic resonance fingerprinting to explore the feasibility of simultaneous T1 and T2 mapping in clinically feasible scan times. In addition to a PD image, our method quantified T1 and T2 with a 0.8x0.8 mm2 in-plane resolution (scan time of 1:20 min per slice). By enabling a fast comprehensive morphological and biochemical assessment, we hope to improve assessment and staging of cartilage damage, predict risk for progression and impact patient management decisions.

Dong Xing¹, Jiao Wang¹, Yunfei Zha¹, Lei Hu¹, Hui Lin², and Yuan Lin^1
1Department of Radiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China, ²GE Healthcare China, Shanghai, China

Although IVDD is a multifactorial disease, it is well accepted that limited nutrition is the final common pathway for IVDD and the changes in the structure or composition of the cartilaginous endplate (CEP) have been considered a crucial role in IVDD. The ultrashort echo time (UTE) sequence has been used in detecting the CEP defects and the visual classification of IVDD , however, a further study utilized the quantitative parameter of T2*-relaxation time would be benefit to understand the causes of disc degeneration of early stage. The purpose of this study was to use 3D-UTE and T2*- mapping sequence to ascertain the relation between CEP Integrity and IVDD.

Yifei Lou¹, Qun He², Xun Jia³, Eric Chang², Christine B Chung², and Jiang Du^2
1Department of Mathematical Sciences, University of Texas Dallas, Dallas, TX, United States, ²Radiology, University of California, San Diego, CA, United States, ³Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, United States

Metallic implants are routinely used to treat advanced joint disease. There is a need for non-invasive diagnosis of wear-induced disease. MRI has obvious advantages. However, conventional MR sequences are subject to severe distortion due to strong susceptibility effects near metal, with little or no signal from important joint tissues such as tendons and cortical bone which have very short T2s. 3D ultrashort echo time (UTE) imaging sequences together with multiple spectral imaging (MSI) can potentially image short T2 tissues and minimize metal artifact. However, 3D UTE-MSI is time-consuming. In this study we aimed to develop 3D UTE-MSI using with vastly undersampling to reduce scan time and a tight-frame regularized compressive sensing (TFCS) technique to reduce streak artifacts. T1, magnetization transfer ratio (MTR) and water content of tissues near metal can potentially being measured using a clinical whole-body scanner

Nian Wang¹ and Yang Xia^1
1Department of Physics and Center for Biomedical Research, Oakland University, Rochester, MI, United States

A new type of laminar appearance was found in the deep region of compressed articular cartilage at the magic angle by high-resolution MRI, but the origin of this appearance was unclear. Recently, the molecular origin of this loading-induced laminar layer in the deep cartilage was attributed to the GAG loss in cartilage. To investigate the characteristics of this additional low-intensity layer, quantitative MRI T1, T2, and T1ρ experiments were carried out under different orientations when the tissue was soaked in different soaking solution.

Matti Hanni^1,2, Mikko J. Nissi^3,4, Jari Rautiainen^3,4, Simo Saarakkala^2,5, Jutta Ellermann⁶, and Miika T. Nieminen^2,7
1Department of Radiology, University of Oulu, Oulu, Finland, ²Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland, ³Department of Radiology, and Medical Research Center Oulu, University of Oulu and Oulu University Hospital, Oulu, Finland, ⁴Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, ⁵Department of Diagnostic Radiology, Oulu University Hospital, Department of Medical Technology, University of Oulu, Oulu, Finland, ⁶Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, United States, ⁷Department of Diagnostic Radiology, University of Oulu and Oulu University Hospital, Oulu, Finland

Reorientational correlation time is a fundamental biophysical property that describes the dynamics of nuclei in any type of tissue. In this abstract, correlation time is investigated as a potential new MRI contrast. It is obtained from MRI T1rho relaxation dispersion measurements of bovine and human articular cartilage in vitro. The fitted correlation times appear to be macromolecule-specific, as well as indicative of early structural changes associated with osteoarthritis.

Matthew F. Koff¹, Parina H. Shah¹, Alissa Burge¹, Mauro Miranda¹, Christina Esposito², Elexis Baral², Thomas W. Bauer³, Allina Nocon⁴, Kara Fields⁴, Stephen Lyman⁴, HSS Adult Reconstruction & Joint Replacement Division⁵, Douglas Padgett⁵, Timothy Wright², and Hollis G. Potter^1
1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, New York, United States, ²Department of Biomechanics, Hospital for Special Surgery, New York, New York, United States, ³Department of Anatomic Pathology, Cleveland Clinic, Cleveland, Ohio, United States,⁴Healthcare Research Institute, Hospital for Special Surgery, New York, New York, United States, ⁵Adult Reconstruction & Joint Replacement Division, Hospital for Special Surgery, New York, New York, United States

synopsis

Luning Wang¹, Mikko J Nissi^1,2, Ferenc Toth³, Michael Garwood¹, Cathy Carlson³, and Jutta Ellermann^1
1Center for Magnetic Resonance Research, University of Minnesota, Twin Cities, Minneapolis, MN, United States, ²Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Finland, ³University of Minnesota, Twin Cities, Minneapolis, MN, United States

Juvenile Osteochondritis Dissecans (OCD) is a disease of epiphyseal cartilage occurring subsequent to failure of cartilage canal blood vessels. Minimum intensity projections of MR susceptibility maps together with MR relaxometry can provide a noninvasive approach for a direct correlation between the quantitative assessment of cartilage matrix and the visualization of the canal degeneration at different time points.

Xiaojuan Li¹, Valentina Pedoia¹, Deepak Kumar¹, Drew Lansdown¹, Cory Wyatt¹, Julien Rivorie¹, Narihiro Okazaki¹, Dragana Savic¹, Matthew F Koff², Joel Felmlee³, Williams Steven³, and Sharmila Majumdar^1
1University of California, San Francisco, CA, United States, ²Hospital for Special Surgery, New York, NY, United States, ³Mayo Clinic, Rochester, MN, United States