MR及动态增强扫描诊断眼眶淋巴瘤的价值

The conventional and dynamic contrast-enhanced MR imaging findings of lymphoma of the orbit

目的评价常规 MR 及动态增强扫描对于眼眶淋巴瘤的诊断价值。方法眼眶淋巴瘤共13例,其中 B 细胞型10例,T 细胞型1例,T-NK 细胞型1例,多发性骨髓瘤1例。13例均行常规 MR 检查,然后采用三维(3D)快速扰相梯度回波(FSPGR)序列进行动态增强扫描,对数据进行后处理后获得动态增强曲线和峰值时间(T_(peak))、最大上升斜率(Slope)、流出率(WR)、最大强化率(ER)等参数。结果 13例眼眶淋巴瘤中有11例发生于眼眶前部的眼睑、泪腺区,常包绕眼球生长,呈"铸形"改变,在 MRI 上10例呈等 T_1、等 T_2信号,增强扫描13例均呈中度强化。13例的动态增强曲线均为速升、速降型,T_(peak)值为(58.7±8.5)s,WR 值为(30.9±9.4)%。13例眼眶淋巴瘤中常规 MRI 正确诊断6例,常规 MRI 加动态增强扫描对13例均作出正确诊断。结论常规 MRI 结合动态增强扫描有利于眼眶淋巴瘤的定性诊断。

Objective To evaluate the diagnostic value of conventional and dynamic contrastenhanced MRI in lymphoma of the orbit. Methods Thirteen cases of lymphoma of the orbit, including B-C （10 cases）, T-C （1 case）, T-NK -C （1 case） lymphoma, and multiple myeloma （1 case）, were studied using conventional MR and dynamic contrast-enhanced MR imaging with 3D fast spoiled gradient echo sequence. Calculated values included time to peak （Tpeak）, washout ratio （WR）, slope and enhancement ratio （ER）, and time-intensity curves （TICs）, and Tpeak, WR, slope and ER were calculated preoperatively. Results Eleven of the 13 lymphomas of the orbit was seen in the anterior portion of the orbit including eyelid and lacrimal gland. On conventional MRI, 10 cases showed iso-intensity on T1 WI and T2WI and all 13 cases showed moderate enhancement after contrast administration. TIC of all 13 cases showed rapid enhancing and wash-out, Tpeak was （58.7 ± 8.5 ） s, and WR was （30.9 ±9.4） %. The accurate diagnosis with only conventional MRI was achieved in 6 out of 13 cases, while the accurate diagnosis was achieved in all 13 cases by using combined conventional MRI and dynamic enhanment MRI. Conclusion onventional MRI combined with dynamic contrast-enhanced MRI is useful for the diagnosis of lymphoma of the orbit.