Szypryt E P, Hardy J G, Hinton C E, Worthington B S, Mulholland R C
Department of Orthopaedic Surgery, Harlow Wood Orthopaedic Hospital, Nottingham, England.
Spine (Phila Pa 1976). 1988 Sep;13(9):1042-8. doi: 10.1097/00007632-198809000-00012.
In a controlled prospective study, 33 rabbits were used to compare the efficacy of magnetic resonance imaging (MRI) to scintigraphy in diagnosing pyogenic infection of the intervertebral disc. A suitable inoculum of Staphylococcus aureus (10(8) organisms) was injected into a test level while a similar volume of sterile culture medium was injected into a control disc in each animal. Plain radiographs, MRI, and scintigraphic bone images then were performed at regular intervals after operation. The imaging studies were interpreted blind, as was the final histologic assessment. Five animals died of respiratory complications following sedation. In the remaining 28 animals, 23 developed infection at the test level, and four developed infection at the control disc. Magnetic resonance imaging was found to be more sensitive than scintigraphy in diagnosing discitis, particularly in the early stages of the disease. The overall results showed MRI had a sensitivity of 93%, specificity of 97%, and accuracy of 95%. There were two false-negative results and one false-positive. In contrast, scintigraphy had a sensitivity of 41%, specificity of 93%, and accuracy of 68%. There were two false-positive and 16 false-negative results. Plain radiographs had a sensitivity of 82%, specificity of 93%, and accuracy of 88%. There were two false-positive and five false-negative results. The MRI appearance of discitis was characteristic from an early stage in the disease, and preceded the changes on scintigraphy and plain radiographs by several days in the majority of cases.
在一项对照前瞻性研究中，33只兔子被用于比较磁共振成像（MRI）与闪烁扫描术在诊断椎间盘化脓性感染方面的疗效。向每只动物的一个测试节段注射适量的金黄色葡萄球菌接种物（10⁸个菌体），同时向对照椎间盘注射等量的无菌培养基。术后定期进行X线平片、MRI和闪烁扫描骨显像检查。影像学检查由不知情的人员解读，最终的组织学评估也是如此。5只动物在镇静后死于呼吸并发症。在其余28只动物中，23只在测试节段发生感染，4只在对照椎间盘发生感染。发现MRI在诊断椎间盘炎方面比闪烁扫描术更敏感，尤其是在疾病的早期阶段。总体结果显示，MRI的敏感性为93%，特异性为97%，准确性为95%。有2例假阴性结果和1例假阳性结果。相比之下，闪烁扫描术的敏感性为41%，特异性为93%，准确性为68%。有2例假阳性和16例假阴性结果。X线平片的敏感性为82%，特异性为93%，准确性为88%。有2例假阳性和5例假阴性结果。椎间盘炎的MRI表现从疾病早期就具有特征性，在大多数情况下比闪烁扫描术和X线平片的改变提前几天出现。
