Department of Radiology, University Hospital Zurich, and Institute for Biomedical Engineering, University of Zurich, Ramistrasse 100, CH 8091 Zurich, Switzerland.
Radiology. 2012 Oct;265(1):194-203. doi: 10.1148/radiol.12111403. Epub 2012 Jul 19.
To determine normative diffusion values of the median nerve at several anatomic locations in healthy men and women of variable age and to compare these normative values with those in patients with carpal tunnel syndrome.
After ethics board approval and written informed consent were obtained, 45 healthy volunteers (30 women, 15 men) and 15 patients (10 women, five men) were studied. Volunteers were divided into three age groups. Magnetic resonance (MR) neurography with diffusion-tensor imaging (DTI) was performed in all study participants at 3.0 T by using a single-shot echo-planar imaging sequence (repetition time msec/echo time msec, 10 123/40; b=1200 sec/mm2). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the median nerve were determined by two readers at three locations: the levels of the distal radioulnar joint, pisiform bone, and hamate bone.
Normative FA and ADC values were calculated for men and women, different age groups, and different anatomic locations. FA and ADC did not differ between men and women (P=.28 and P=.38, respectively). FA decreased and ADC increased when moving from proximal to distal locations (P<.001). FA decreased and ADC increased significantly with age (P<.001). There was a significant difference between healthy volunteers and patients with carpal tunnel syndrome (P<.001 for both FA and ADC). An FA threshold of 0.47 and an ADC threshold of 1.054×10(-3) mm2/sec might be used in the diagnosis of carpal tunnel syndrome.
Normative diffusion values for MR neurography of the median nerve with DTI depend on the anatomic location and age but not on sex. Age-specific FA and ADC threshold values might be used to diagnose carpal tunnel syndrome.
确定健康男女不同年龄的正中神经在多个解剖部位的正常扩散值，并将这些正常值与腕管综合征患者进行比较。
在获得伦理委员会批准和书面知情同意后，对 45 名健康志愿者（30 名女性，15 名男性）和 15 名患者（10 名女性，5 名男性）进行了研究。志愿者分为三组。所有研究参与者均在 3.0T 磁共振（MR）神经成像仪上进行弥散张量成像（DTI），采用单次回波平面成像序列（重复时间毫秒/回波时间毫秒，10123/40；b=1200 秒/mm2）。两名读者在三个位置（桡尺远侧关节水平、豌豆骨和钩骨水平）确定正中神经的部分各向异性（FA）和表观扩散系数（ADC）。
计算了男性和女性、不同年龄组和不同解剖部位的正常 FA 和 ADC 值。男性和女性的 FA 和 ADC 之间没有差异（分别为 P=.28 和 P=.38）。FA 随着从近端到远端位置的移动而降低，ADC 随着移动而增加（P<.001）。FA 和 ADC 随年龄显著降低（P<.001）。健康志愿者和腕管综合征患者之间存在显著差异（FA 和 ADC 均 P<.001）。FA 阈值为 0.47，ADC 阈值为 1.054×10(-3)mm2/sec 可能用于诊断腕管综合征。
DTI 对正中神经磁共振神经成像的正常扩散值取决于解剖位置和年龄，而与性别无关。特定年龄的 FA 和 ADC 阈值值可能用于诊断腕管综合征。
