腰椎间盘MRI局限性高信号区的影像学分析

目的分析腰椎间盘局限性高信号区（HIZ）的影像学特征,为临床诊断和相关研究提供参考。方法回顾分析138例伴有HIZ的腰椎MRI资料。对11例16个伴有HIZ的腰椎间盘行CT椎间盘造影（CTD）。立体定位HIZ并对照分析CTD与MR图像。结果腰椎间盘HIZ在MR矢状位图像呈点状（14.36%）,圆形（58.01%）,长椭圆形（17.13%）或逗点状（10.50%）,其中圆形最常见。轴位像为线样或梭形,与CTD显示的环状破裂一致。本组HIZ均位于腰椎纤维环外缘。73个椎间盘的HIZ与椎间盘内破裂征象同时出现,1个椎间盘HIZ位于突出物下方。51个腰椎间盘矢状位图像的2个或3个相邻层面同一位置出现HIZ。CTD Dallas Ⅲ级者疼痛诱发试验多为阴性（6/7）,IV级者多为阳性（8/9）。结论腰椎间盘HIZ代表椎间盘纤维环中与放射状破裂相连的环状裂隙,临床多见于椎间盘突出前的椎间盘内破裂。矢状位连续多层面HIZ提示裂隙较长,复制性疼痛发生几率高。

Imaging analysis of high-intensity zone on magnetic resonance imaging in lumbar disc

Objective To analyze the images of lumbar intervertebral high-intensity zone (HIZ) and provide reference to clinical diagnosis and further research. Methods Lumbar MR images of 138 cases with HIZs were retrospectively analyzed. Sixteen lumbar intervertebral discs with HIZ underwent CT discography (CTD). HIZs were located in 3 dimensions and the CTD images were compared with MRIs. Results Lumbar HIZs were described as dot-like (14.36%), round-like (58.01%), oblong-like (17.13%) or comma-like (10.50%) in sagittal plane. Round shape was the most familiar style. Linear and fusiform shapes were the major types of the HIZ in transverse plane consistent with the cricoid rupture in CTD. All of the HIZs were located near the outer edge of annulus fibrosus. The HIZs were founded simultaneously with internal disc disruption (IDD) signs in 73 discs and below the herniation of nucleus pulposus in one disc. HIZs of 51 discs occurred in the same position of 2 or 3 adjacent sagittal planes in MR imagings. According to modified Dallas' discogram scale, most of the grade IV (8/9) were pain reproduction and most of the grade III (6/7) were absent pain reproduction in provocation discograme. Conclusion The HIZ represents the cricoid rupture connected with the radial disruption in annulus fibrosus of lumbar inter-vertebral disc, and can be founded frequently in discs of IDD before disc herniation. The HIZ displayed in sequential sagittal MR images indicate a longer rupture and a higher risk of reproductive pain.