Evaluation of fat content in vertebral bone marrow and the changes in different vertebrae using MR spectroscopy / 实用放射学杂志

ABSTRACT

Objective To probe the precision of the magnetic resonance spectroscopy (MRS)in assessing the fat content in the vertebral bone marrow and the changes at different vertebrae.Methods A total of 46 female volunteers were recruited in this study. After routine MRI examination,single voxel (SV)was chosen for the 1 H-MRS acquisition at L1 -L4 vertebral body.Thirty subjects were scanned twice to evaluate the precision of MRS.The fat fraction (FF%),unsaturation index (UI)and coefficients of variation (CV) were calculated by amplitude and area under the peak respectively.The changes of fat content in marrow at L1 -L4 vertebrae was further evaluated.Results The CV related to peak amplitude was 1.7% in quantification of vertebral FF%,while the CV related to peak area was 6.3%.In quantification of vertebral UI,the CV related to amplitude and area was 2.4% and 7.8% respectively.The FF% was ascended from L1 to L4,while UI of bone marrow declined.A significant correlation was observed between FF% and UI (r=-0.714,P <0.01).The correlation of FF% among L1 -L4 were also significantly observed (r =0.612 -0.923,P <0.01). Conclusion MRS at 3.0 T provides reliable measurement for marrow fat content with a good precision associated with amplitude. Meanwhile,there is a preferential increase in saturated lipids compared to unsaturated lipids from L1 to L4.There is a high correlation of FF%among L1-L4.MRS is a valuable tool for providing complementary information on osteoporosis research.