自发性脑出血患者脑微出血MR磁化率与体积的相关性研究

Preliminary Study of Relationship Between MR Susceptibility and the Volume in Cerebral Microbleeds

目的分析自发性脑出血(intracerebral hemorrhage,ICH)患者颅内脑微出血灶(cerebral microbleeds,CMBs)MR磁化率与体积的相关性,探讨CMBs磁化率在评估ICH风险性中的价值。方法回顾性分析24例经MR多回波磁敏感定量成像(quantitative susceptibility mapping,QSM)技术检查发现颅内存在CMBs灶的ICH患者资料,分别在MR幅度图及相位图上逐个测量CMBs的体积及磁化率,采用Spearman相关分析CMBs磁化率与其体积之间的相关性;Pearson相关分析CMBs平均磁化率与ICH发病时间之间的相关性。结果 88.7%的CMBs磁化率分布范围在0.0977～16 ppm/mm3,其中58.4%集中在0.0977～8 ppm/mm3。CMBs总磁化率与其体积之间存在一定的相关性(r=0.69);但将CMBs磁化率限定在0.0977～8 ppm/mm3和≥8 ppm/mm3两组范围内进行分析时,CMBs磁化率和其体积之间无明显相关(r=0.294,r=0.226,P>0.05)。同时发现,CMBs平均磁化率与ICH发病时间呈负相关(r=-0.445)。结论 CMBs体积不能完全反映CMBs的内在演变进程,而CMBs的磁化率有可能是一项直接评价ICH风险性的可靠指标。

Objective To analyze the relationship between magnetic susceptibility and the volume of cerebral mierob- leeds （CMBs） in the patients with spontaneous intracerebral hemorrhage（ICH）. To investigate the value of the MR magnet- ic susceptibility in the assessment of CMBs risk. Methods The data of 24 ICH patients with CMBs who had performed MR multi echo quantitative susceptibility mapping （QSM） were retrospectively reviewed. The magnetic susceptibility and volume were measured respectively in QSM. The Spearman correlation was used to determine the relationship between mag- netic susceptibility and volume. The Pearson correlation was used to determine the relationship between magnetic suscepti- bility of CMBs and the time of ICH onset. Results There was a correlation between the magnetic susceptibility and vol- ume（r =0.69）. The magnetic susceptibility concentrated from 0. 0977 to 16 ppm · mm3 in 88.7% of CMBs , and the magnetic susceptibility concentrated from 0. 0977 to 8 ppm · mm3 in 58.4% of CMBs. However, when the magnetic sus- ceptibility was limited to 0.0977 to 8 ppm·mm3 or more, there was no correlation between the magnetic susceptibility and volume （r = 0. 294, r = 0. 226,P 〉 0.05）. There was negative correlation between the magnetic susceptibility of CMBs and the onset-time of ICH （ r = - 0. 445 ）. Conclusion The volume of CMBs could not fully reveal the intrinsic evolution process of CMBs, while the magnetic susceptibility may be a reliable indicator in the direct evaluation of CMBs risk.