Detection of bone marrow changes related to estrogen withdrawal in rats with a tabletop stray-field NMR scanner.
Osteoporosis is characterized by a decrease in bone mineral density (BMD). A preliminary stage of the disease is progressive bone marrow adiposity, caused by imbalance between osteogenesis and adipogenesis in the marrow. Detection of osteoporosis relies on the quantification of BMD with techniques such as dual-energy X-ray absorptiometry. This work aimed to detect bone marrow changes in an experimental model of osteopenia using a low-field tabletop NMR scanner.



An experiment was performed on 32 female rats, 3 months old, 16 of which were ovariectomized (OVX) and 16 were sham-operated (sham). The femur and tibia from both hind limbs were isolated and underwent ex vivo NMR scans at four time points after the OVX and sham operations. NMR scans were complemented by BMD measurements and histology.



Significant changes in the bone marrow of ovariectomized rats, relative to sham operated rats, were observed after 3.5 and 4.5 months. Bone marrow adiposity was detected by significant changes in T1and T2relaxation times, and in the diffusion coefficient.



This study suggests a potential detection of changes to the bone marrow using a tabletop NMR device. Clinical translation may facilitate screening, early detection of bone weakening as a result of estrogen withdrawal, and monitoring of treatment efficacy. Magn Reson Med 78:860-870, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
Yifat
Y
Sarda
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
Elad
E
Bergman
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
Inbar
I
Hillel
Department of Oral Biology, School of Dental Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
Itzhak
I
Binderman
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
Uri
U
Nevo
D000818:Animals; D015519:Bone Density; D001853:Bone Marrow / Q000737:chemistry / Q000000981:diagnostic imaging*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010024:Osteoporosis / Q000000981:diagnostic imaging*; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013977:Tibia / Q000000981:diagnostic imaging
Stray field NMR; Unilateral NMR; early detection; low field; osteoporosis