扩散加权b0图像对脑微出血的诊断价值

Role of b0 images obtained from diffusion weighted echo-planar sequences in detection of cerebral microbleeds

目的探讨扩散加权b0图像对脑微出血(cerebral microbleeds,CMBs)的诊断价值。方法回顾性分析95例接受磁敏感成像(susceptibility-weighted imaging,SWI)、扩散加权成像的患者图像资料,与磁敏感加权成像对比,评价b0图像对CMBs的检出率和诊断结果的可靠性。结果 95例中,SWI对CMBs的病例检出率是32%,检出632个CMBs,b0图像对CMBs的病例检出率是29%,检出201个CMBs,增加的CMBs均匀分布在各部位。两位阅片者对SWI图像Kappa值为0.86,对b0图像的Kappa值为0.83;同一阅片者对SWI的Kappa值为0.85,b0图像Kappa值为0.84。结论 b0图像在没有增加额外扫描时间的情况下,可以检出大部分CMBs,诊断结果具有很好的可靠性、可重复性。

Objective To evaluate the role of b0 images obtained from diffusion weighted echo-planar images(EPI） in detection of cerebral microbleeds. Methods Ninety-five patients treated at our hospital were included and underwent clinical evaluation and a magnetic resonance imaging protocol including both DWI and SWI. Images were analyzed for numbers and locations of CMBs. Intraobserver and interobserver reliabilities for the detection of CMBs were assessed on SWI and b0 images. Results The prevalence of CMBs was 32% on SWI and 29% on b0 images. A total of 632 and 201 MBs were detected on SWI and b0 images,respectively. The increase in the number of CMBs on SWI was equally distributed across brain regions. The interobserver agreement for the detection of CMBs was excellent,with a kappa value of 0. 86 for CMBs on SWI and of 0. 83 on b0 images by two observers. Intraobserver agreement was also excellent,with a kappa value of 0. 85 for SWI and of 0. 84 for b0 images. Conclusions b0 images can detect the majority of CMBs without additional acquisition time. The assessment of CMBs is accurate and reproducible on b0 images,with excellent interobserver and intraobserver agreement.