活体激发骨髓造血的磁共振波谱研究

Magnetic resonance spectroscopy of bone marrow mobilization in vivo

目的用骨髓磁共振波谱(MRS)来监测被rhG-CSF激发后髂骨骨髓中水和脂肪的变化。方法选取将作自体干细胞移植的11名淋巴瘤和多发性骨髓瘤患者,注射rhG-CSF来激发骨髓干细胞释放前后,取髂骨内约8mm边长的正立方体,用PRESS法进行单体素氢质子波谱分析。在rhG-CSF注射前(0周)和注射后1、2、4周等时间分别作MRS。采用1个固定的TE和11个不同的TR参数进行扫描,用于测定立方体内水和脂肪的T1值(T1w和T1f);计算水和脂肪波峰振幅比代表髂骨骨髓中水和脂肪的比值(water/fat),由公式W%=(water/fat)/(water/fat+1)和F%=1/(water/fat+1)可分别计算出骨髓中水和脂肪含量的百分比。对W%、T1w、F%、T1f等参数进行不同时间的纵向对比和同一时间不同参数的横向对比,并与外周血CD34+的浓度等进行比较。结果W%、T1w、F%、T1f在1、2、4周与0周相比,除了W%在1周与0周对比的差异有显著性意义外,其余的差异均没有显著性意义。所有时间段的W%和T1w之间的Pearson’s相关关系没有显著性意义,而F%和T1f之间的Pearson’s相关关系却有显著性意义,而且F%和T1f之间的线性拟合也有显著性意义。结论骨髓干细胞被动员后第一周骨髓中相对水的含量明显增加。F%与T1f的相关关系密切,并其变化成线性相关,可作为MRS活体监测骨髓脂肪含量变化的量化指标。

Objective To follow up the change of water and fat in iliac in magnetic resonance spectroscopy（MRS）after priming in rhG-CSF administration.Methods Eleven patients of lymphoma and myeloma during pretransplant priming were included in this study.MRS investigation was scheduled four times：at study entry,one-two-and four-weeks following priming.MRS were performed at post iliac of a cube 8 mm×8 mm×8 mm in 11 different sequences in order to calculated T1 of water component（T1w）and fat component（T1f）.The peak amplitudes of the water and fat components（water/fat）were measured for the calculations：W%=（water/fat）/（water/fat＋1）,F%=1/（water/fat＋1）.Results W%,T1w,F% and T1f in 1 w,2 w,4 w were not significant difference comparing to that of 0 w except W% paired 0-1 w.Pearson＇s correlation between W% and T1w was no significant,but F% and T1f,a linear fit of F% and T1f were significant.Conclusion The changed of water content was obvious in the first week after stem cells mobilization.The change of F% and T1f in bone marrow was parallel,and consequence to be indexes in following up the change of fat component in marrow.