Experiment design and feasibility of BOLD and MRS multimodal fMRI in analysis of brain effect induced by acupuncture / 中国医学影像技术

ABSTRACT

Objective To establish the methodology of combining BOLD and 1H-MRS for investigating correlation between the deactivation in medial prefrontal cortex (MPFC) and gamma-aminobutyric acid (GABA) concentration by acupuncture at LI4 (Point Hegu),and to optimize the experimental technique and procedure.Methods Twenty healthy adult volunteers were enrolled.During fMRI-BOLD scanning,each subject received acupuncture at right LI4 (Point Hegu).MRS scanning was based on MEGA-PRESS sequence,and ROIs were located at bilateral MPFC.The task BOLD fMRI was block design,including 3 stimulations (30 s) with 2 intervals (2 min).Then MRS scanning was performed before and after BOLD.The quantitative values of the BOLD positive and negative activations (Pm) and GABA concentrations were calculated.Results All 20 subjects completed BOLD fMRI scanning,and met the postprocessing requirements.MRS images of 9 subjects with good image quality were included in analysis.Among all 20 subjects,positive activation (Pm=1.17± 0.16) was observed in 9,while negative activation (Pm =-1.31 ± 0.17) was observed in 11 subjects.The GABA average values before and after the acupuncture were (19.93 ±1.04) nmol/L and (20.04±0.81)nmol/L,respectively,and the average amplitude between post-and pre-acupuncture was (0.11 ± 1.60)nmol/L.Conclusion The success rate of this method for quantitative study of brain function established multimodal-functional (BOLD-fMRI and MRS) was acceptable,and the multimodal brain function changes as well as the quantitative values were observed in the brain region during acupuncture.Combined BOLD and MRS quantitative method is feasible for testing acupuncture response in the brain.