Victor Casula1,2, Joonas Autio3, Mikko J Nissi1,4,5,6, Edward J Auerbach4, Jutta Ellermann4, Eveliina Lammentausta7, Miika T Nieminen1,2,7. 1. Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland. 2. Medical Research Center, University of Oulu and Oulu University Hospital, Oulu, Finland. 3. Center for Life Science and Technologies, RIKEN, Kobe, Japan. 4. Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN. 5. Department of Applied Physics, University of Eastern Finland, Kuopio, Finland. 6. Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland. 7. Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland.
Abstract
PURPOSE: The aim of the present work was to validate and optimize adiabatic T1ρ and T2ρ mapping for in vivo measurements of articular cartilage at 3 Tesla (T). METHODS: Phantom and in vivo experiments were systematically performed on a 3T clinical system to evaluate the sequences using hyperbolic secant HS1 and HS4 pulses. R1ρ and R2ρ relaxation rates were studied as a function of agarose and chondroitin sulfate concentration and pulse duration. Optimal in vivo protocol was determined by imaging the articular cartilage of two volunteers and varying the sequence parameters, and successively applied in eight additional subjects. Reproducibility was assessed in phantoms and in vivo. RESULTS: Relaxation rates depended on agarose and chondroitin sulfate concentration. The sequences were able to generate relaxation time maps with pulse lengths of 8 and 6 ms for HS1 and HS4, respectively. In vivo findings were in good agreement with the phantoms. The implemented adiabatic T1ρ and T2ρ sequences demonstrated regional variation in relaxation time maps of femorotibial cartilage. Reproducibility in phantoms and in vivo was good to excellent for both adiabatic T1ρ and T2ρ . CONCLUSIONS: The findings indicate that sequences are suitable for quantitative in vivo assessment of articular cartilage at 3 T. Magn Reson Med 77:1265-1275, 2017.
PURPOSE: The aim of the present work was to validate and optimize adiabatic T1ρ and T2ρ mapping for in vivo measurements of articular cartilage at 3 Tesla (T). METHODS: Phantom and in vivo experiments were systematically performed on a 3T clinical system to evaluate the sequences using hyperbolic secant HS1 and HS4 pulses. R1ρ and R2ρ relaxation rates were studied as a function of agarose and chondroitin sulfate concentration and pulse duration. Optimal in vivo protocol was determined by imaging the articular cartilage of two volunteers and varying the sequence parameters, and successively applied in eight additional subjects. Reproducibility was assessed in phantoms and in vivo. RESULTS: Relaxation rates depended on agarose and chondroitin sulfate concentration. The sequences were able to generate relaxation time maps with pulse lengths of 8 and 6 ms for HS1 and HS4, respectively. In vivo findings were in good agreement with the phantoms. The implemented adiabatic T1ρ and T2ρ sequences demonstrated regional variation in relaxation time maps of femorotibial cartilage. Reproducibility in phantoms and in vivo was good to excellent for both adiabatic T1ρ and T2ρ . CONCLUSIONS: The findings indicate that sequences are suitable for quantitative in vivo assessment of articular cartilage at 3 T. Magn Reson Med 77:1265-1275, 2017.
Authors: Mei Wu; Ya-Jun Ma; Jiang Du; Mouyuan Liu; Yanping Xue; Lillian Gong; Zhao Wei; Saeed Jerban; Hyungseok Jang; Douglas G Chang; Eric Y Chang; Liheng Ma Journal: Eur Radiol Date: 2022-03-31 Impact factor: 7.034
Authors: Saeed Jerban; Takehito Hananouchi; Yajun Ma; Behnam Namiranian; Erik W Dorthe; Jonathan H Wong; Niloofar Shojaeiadib; Mei Wu; Jiang Du; Darryl D'Lima; Christine B Chung; Eric Y Chang Journal: J Orthop Res Date: 2022-01-28 Impact factor: 3.102