全身一体化磁共振成像和全身扩散加权成像对淋巴瘤结内病变的检出能力

Evaluation of whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma

目的评价全身一体化磁共振成像（MRI）和全身扩散加权成像（DWI）对淋巴瘤结内病变的检出能力和临床价值。方法对23例病理证实为淋巴瘤的患者行全身一体化MRI和全身DWI扫描。全身一体化MRI采用常规冠状位扫描；全身DWI行轴位连续多次分段扫描，然后将各段图像重建成全身图像。结果23例患者共检出417枚淋巴结，其中全身一体化MRI的总检出率是79．1％，全身DWI的总检出率是89．7％。全身一体化MRI对长径为〈2cm和2～3cm淋巴结的检出率分别为70．9％和79．4％，全身DWI的检出率分别为85．2％和90．1％，两种检查方法差异有统计学意义（均P〈0．01），而对长径〉3cm淋巴结的检出率（94．7％和97．9％），差异无统计学意义（P〉0．05）。全身一体化MRI和全身DWI对颈部、锁骨上下、纵隔和腋窝淋巴结的检出率均较高，但二者的差异并无统计学意义（均P〉0．05）；而对于腹膜后、盆腔和腹股沟淋巴结，全身一体化MPd的检出率分别为51．2％A3．8％和52．2％，均明显低于全身DWI的检出率（83．7％、71．9％和87．0％，均P〈0．01）。结论全身一体化MRI和全身DWI对淋巴瘤结内病变有较高的检出率，具有一定的临床应用价值。

Objective To evaluate the whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma. Methods Whole body MR/ and diffusion-weighted MRI （DWI） were performed in 23 patients with histologically proven lymphoma. A conventional coronal MRI scan from head to inguinal groove was done for whole body scanning. In the DWI, axial MRI scans were performed after segmentation based on SENSE technique, and all images were merged into whole body image reconstruction by software. Results 417 lymph nodes were detected by MRI in the 23 patients. The overall positive rate of whole body MRI and DW1 was 79.1% and 89.7%, respectively. It was 70.9% versus 85.2% and 79.4% versus 90. 1% for the lymph nodes of 〈 2 em and 2-3 cm in diameter, with a significant difference between the two methods （P 〈 0.01 ）. However, it was 94.7% versus 97.9% for the lymph nodes of 〉 3 cm in diameter, not significantly different between the two methods （P 〉 0.05 ）. Both methods had similar sensitivity in detecting the lymph nodes in the neck, supraclavicular and infraelavicular fossae, mediastinum and axillary fossa. However, the positive rate of whole body MR/was 51.2% ,43.8% and 52.2%, significantly less sensitive than 83.7%, 71.9% and 87.0% , respectively, by DWI in detecting the lymph nodes in the retroperitoneal space, pelvic cavity and inguinal groove （ all P 〈 0.01 ）. Conclusion Both whole body MRI and diffusion-weighted MRI have a relative high sensitivity in detecting intranodal lesions for patients with lymphoma, showing a certain value in clinical application.