静音磁共振在婴幼儿头颅检查中的应用

Application of Silent MR in Infant Head Examination

目的探讨静音MRI在婴幼儿头颅检查中的应用价值。资料与方法回顾性分析婴幼儿头颅MRI检查,常规组391例,静音组443例。比较两组检查成功率,测量各组扩散加权成像(DWI)、T2WI、T1WI序列噪声强度,并选取30名听力正常的志愿者对各序列噪声强度进行主观评分。测量各序列信噪比和对比噪声比,以病灶辨别度、病灶边缘区分度、灰白质区分度为指标对各序列进行主观图像质量评分。以综合诊断度为指标对两组检查进行主观图像质量评分。结果与常规组比较,静音组检查成功率较高(97.7%比88.2%,P<0.05),二次镇静率较低(4.1%比23.9%,P<0.05);Silent DWI、Silent T2WI、Silent T1WI较常规序列噪声强度降低14.5%、36.1%、33.9%;主观噪声强度评分优于常规组;信噪比均低于常规序列,对比噪声比均高于常规序列(P均<0.05)。除病灶边缘区分度,静音序列其余主观图像质量评分指标均高于常规组(P<0.05)。结论尽管部分客观图像质量数据与主观图像质量评分结果不统一,但静音技术能有效提高检查成功率,降低噪声强度,且综合诊断度优于常规MRI。故静音MRI较常规MRI更适用于婴幼儿头颅检查。

Purpose To explore the application value of silent MRI in infant head examinations. Materials and Methods Infant head examinations were analyzed retrospectively, with 391 cases in conventional group and 443 cases in silent group. Success rates of the two groups were subjected to statistics, noise intensity of DWI, T2WI and T1WI sequences in each group was measured, and 30 volunteers with normal hearing were selected for the subjective scoring of the noise intensity of each sequence. The signal to noise ratio(SNR) and the contrast to noise ratio(CNR) of each sequence were calculated. The lesion discrimination, lesion margin distinction degree and gray matter distinction degree were used as indices perform subjective image quality scoring. Both groups underwent the subjective image quality scoring according to comprehensive diagnosis degree. Results The success rate of the silent group was higher than that of the conventional group(97.7% vs. 88.2%, P<0.05), and the secondary sedation rate was lower(4.1% vs. 23.9%, P<0.05), the noise intensity of Silent DWI, Silent T2WI and Silent T1WI sequences was 14.5%, 36.1% and 33.9% lower than that of conventional sequences, and the subjective noise intensity score was better than that of the conventional group. The SNR was lower than that of the conventional sequence, and the CNR was higher than that of the conventional sequence(P<0.05). Apart from the lesion discrimination, the remaining subjective image quality scoring indices of the silent sequence were all higher than those of the conventional group(P<0.05). Conclusion Although some objective image quality data is not consistent with the subjective image quality scoring results, the silent MRI could effectively improve the success rate of examinations, and reduce the noise intensity, with its comprehensive diagnosis degree better than that of conventional MRI. Therefore, silent MRI is more suitable for infant head examinations than conventional MRI.