Magnetic resonance imaging, computed tomography, and myelography in the diagnosis of recurrent lumbar disc herniation

Abstract

Thirteen patients with recurrent symptoms after lumbar discectomy were evaluated. All the patients were enrolled in the study on the basis of clinical symptoms and signs only. The patients were examined with MRI, CT, and myelography in order to compare a) the clinical findings with the imaging investigations, b) the predictive value of the different investigations, and c) the clinical and investigative results with the operative findings. All patients were operated upon according to the clinical findings, and the surgical results were used as the final diagnosis. In six patients a new disc herniation was detected. In the remaining cases surgery revealed either scar tissue or nothing to explain the recurrence of the symptoms. The three imaging modalities were analysed by receiver operating characteristic (ROC) curves. The areas under the ROC curves were 0.68 for MRI, 0.83 for CT, and 0.43 for myelography. The difference in areas between CT and myelography was significant (p less than 0.05). The results indicate that CT has the highest predictive value for demonstrating the recurrence of a lumbar disc herniation.

Contrast enhanced computed tomography and magnetic resonance imaging in the diagnosis of recurrent disc herniation

“…There was no significant difference between CT and MRI [2]. In a study where 12 patients out of 32 underwent repeated surgery it was concluded that postmyelographic CT was useful for distinguishing abnormalities in the postoperative spine.…”

“…The effect may be caused by a recurrent disc herniation, scar tissue or arachnoiditis and the diagnostic value of myelography is insignificant [2,14]. Myelography is unable to predict a recurrent disc herniation [12] or a successful re-operation [13].…”

“…CT visualizes the cause of the root compression better [2,14]. A lateral mass close to the disc and the nerve root is often detected.…”

Agreement between magnetic resonance imaging, myelography, and surgery for detecting recurrent, thoracolumbar intervertebral disc extrusion in dogs

“…Imaging of patients that have had previous spinal decompressive surgery can be complicated by the presence of haemorrhage, residual disc material, scar or granulation tissue at the site of the previous surgery as well as metal artefact related to the first surgery. Haemorrhage, the D. Reynolds et al: Recurrent thoracolumbar IVDD imaging in dogs presence of gelatin sponge or a fat graft in the early postoperative period, or scar and granulation tissue later on, can also cause compressive lesions which may be difficult to differentiate from herniated disc material (21,(23)(24)(25)(26). In fact, a recent study evaluating the amount of residual disc material immediately postoperatively using CT found that 100% of dogs had residual disc material at the site of decompression and some dogs had more than 100% the initial amount of compression which was attributed to the presence of haemorrhage at the surgical site (21).…”

“…Surgery leads to inflammation and subsequent scar tissue formation, which may also influence the ability to detect recurrent lesions at the same site or at new disc space when using MRI, since contrast enhancement can be detected for months following surgery (27)(28)(29). Studies evaluating advanced imaging and myelography for recurrent lesions in humans have shown that contrast enhanced MRI and CT could differentiate between granulation tissue and new disc material, whereas myelography could not separate what portion of the compressive lesion was caused by disc or by granulation tissue (26,30). In contrast, it has been previously suggested that myelography may be more accurate in determining the active lesion in the face of multilevel spinal disease in humans (31).…”