三维MR增强扫描在多发脑转移瘤诊断中的价值

Value of 3DE MR in the Diagnosis of Multiple Brain Metastasis

目的探讨三维MR增强扫描(3DE MR)在诊断多发性脑转移瘤(BM)中的价值。方法筛选临床拟诊为BM患者64例行MR平扫及增强检查,增强扫描包括2DE MR和3DE MR两种扫描方式,根据3DE MR的图像特征及临床病史,选取有多发BM病灶的患者35例。对两种不同增强扫描方式图像质量进行分析,并在显示病灶数目、大小方面进行比较。结果 (1)图像质量。3DE MR图像上平均病灶与脑白质比值(LBR)为1.43±0.33,平均信噪比(SNR)为21.98±10.1,平均对比噪声比(CNR)7.72±4.45,2DE MR图像上平均LBR为1.21±0.22,平均SNR为30.52±11.28,平均CNR为6.63±4.60,利用配对资料t检验对两种扫描方式所得图像的参数进行统计学分析,得出LBR和SNR两个指标在两种扫描方式间有差异,CNR在两种扫描方式间无差异。(2)病灶数目比较。在35例BM患者中3DE MR较2DE MR多发现121个病灶,平均每例多发现3.4个病灶。(3)病灶大小比较。本组病例中,以2DE MR扫描方式中所发现的336个病灶为准,测量对应病灶在不同扫描方式中的大小,在2DE MR中所测病灶平均大小为(8.87±0.42)mm,3DE MR中平均大小为(9.76±0.43)mm,利用配对资料的t检验对两种扫描方式所测得病灶大小进行统计学分析,所有病灶在两种扫描方式中所测大小存在差异。结论 3DE MR较常规2DE MR发现BM更敏感,在显示病灶数目、大小方面明显优于2DE MR,可明显降低2DE MR扫描方式的漏诊率及误诊率,应成为临床BM常规增强扫描方式。

Objective To explore the value of 3DE MR in the diagnosis of multiple brain metastasis（ BM）. Methods A total of 64 BM and suspected BM patients who undergone MR plan scan and contrast enhanced scan（ 2DE MR and3 DE MR） were selected. Then according to the findings of 3DE MR and the history of the clinic,35 patients with multiple BM were selected. The analysis and comparison of image quality on the two different enhancement scanning modes were done. At the same time,comparison of the number,size on these two scanning modes were done. Results（ 1） Quality of images： The average LBR was 1. 43 ＋ /- 0. 33,the average SNR was 21. 98 ＋ /- 10. 1,the average CNR was 7.72 ＋ /- 4. 45 on 3D MR respectively. The average LBR was 1. 21 ＋ /- 0. 22,the average SNR was 30. 52 ＋ /-11. 28,the average CNR was 6. 63 ＋ /- 4. 60 on 2DE MR respectively. Using paired t- test to analyze the difference of above parameters which was obtained by two types of scanning was done. There was a significant difference on LBR and SNR between the two kinds of scanning modes. There was no difference on CNR between the two types of scanning.（ 2） In total 35 cases when compared with 2DE MR,3DE MR,a total of 121 lesions were found.（ 3） Size： the measurement of336 lesions were done with 2DE MR on 2DE MR and 3DE MR separately. The average size was about 8. 87 ＋ /- 0. 42 on 2DE MR and the average size was about 9. 76 ＋ /- 0. 43 on 3DE MR. Using paired t- test to analyze the difference of size,which was obtained by two types of scanning was done. There was a significant difference in size between 2DE MR and 3DE MR. Conclusion 3 DE MR is more sensitive in finding BM than 2DE MR. The number,size is displayed better than 2DE MR. 3DE MR can obviously reduce missed diagnosis and misdiagnosis rate caused by 2 DE MR scan mode.3DE MR should be considered as the routine enhancement scanning way.