T1WIR在颅脑非肿瘤性病变中的应用

Usefulness of T1 weighted inversion recovery in revealing non-tumor lesions of the brain

目的通过自旋回波序列T1WI(T1WSE)与反转恢复序列T1WI(T1WIR)的比较研究,探讨T1WIR在颅脑非肿瘤性病变诊断中的价值。方法34例颅脑非肿瘤性病变患者行TIWSE和T1WIR成像,计算并比较两序列平扫灰质与白质、脑脊液与灰质的对比率(CR)和对比噪声比(CNR),比较两序列对基底节的显示情况。观察增强前后两序列对病灶的显示情况。结果T1WIR上灰质与白质、脑脊液与灰质的CR和CNR均明显高于T1WSE,其对基底节的显示亦更清楚。平扫图像上,50%在T1WIR上病灶的显示优于T1WSE,44.1%在两序列上显示相同,5.9%病例中的低信号病灶在T1WIR上显示的更清楚,但高信号出血在T1WSE显示更为清楚且范围更广。16例行增强检查者,13例在两序列上显示相同,2例烟雾病的"常春藤征"和1例静脉畸形在增强T1WSE上显示清楚,而T1WIR未能明确显示。结论T1WIR在颅脑非肿瘤性病变的诊断中可以替代T1WSE。尤其是对低信号病灶的显示,但在显示合并的少量出血、异常的小血管方面存在劣势。

Objective To determine the value of T1 weighted inversion recovery （T1WIR） in revealing non-tumor lesions of the brain by comparing with T1 weighted spin echo （T1WSE）. Methods Thirty-four patients with non-tumor lesions of brain were underwent both T1WSE and T1WlR. T1WSE and T1WIR images were compared for contrast ratio （CR） and contrast-to-noise ratio （CNR） of gray matter-to-white matter and CSF-to-gray matter. The displaying of basal ganglia and lesion were compared between images of two sequences. Results CR and CNR of gray matter-to-white matter and CSF-to- gray matter were higher on T1WIR than on T1WSE, and basal ganglia was clearer on T1WIR. On plain scan images, T1WIR were superior in 50% patients and equal in 44.1% patients to T1WSE; in 5.9% patients, T1WIR were superior in displaying hypo-intensity lesions, but hyper-intensity hemorrhage were more obvious and wider on T1WSE. On post-contrast images in 16 patients, two sequences images were equal in 13 patients, ivy sign of 2 cases with Moyamoya disease and 1 venous malformation were clearly displayed on postenhanced T1WSE images, but not on posteenhanced T1WIR. Conclu- sion T1WIR can substitute for T1WSE in revealing non-tumor lesions of the brain, especially in displaying hypo-intensity lesions, but it has deficient in displaying small amounts hemorrhage and abnormal small vessel.