Study design A reliability study was conducted Objectives To develop a classification system for lumbar disc degeneration based on routine magnetic resonance imaging, to investigate the applicability of a simple algorithm, and to assess the reliability of this classification system Summary of background data A standardized nomenclature in the assessment of disc abnormalities is a prerequisite for a comparison of data from different investigations The reliability of the assessment has a crucial influence on the validity of the data Grading systems of disc degeneration based on state of the art magnetic resonance imaging and corresponding reproducibility studies currently are sparse Methods A grading system for lumbar disc degeneration was developed on the basis of the literature An algorithm to assess the grading was developed and optimized by reviewing lumbar magnetic resonance examinations The reliability of the algorithm in depicting intervertebral disc alterations was tested on the magnetic resonance images of 300 lumbar intervertebral discs in 60 patients (33 men and 27 women) with a mean age of 40 years (range, 10-83 years) All scans were analyzed independently by three observers Intra- and interobserver reliabilities were assessed by calculating kappa statistics Results There were 14 Grade I, 82 Grade II, 72 Grade III, 68 Grade IV, and 64 Grade V discs The kappa coefficients for intra- and interobserver agreement were substantial to excellent: intraobserver (kappa range, 084-090) and interobserver (kappa range, 069-081) Complete agreement was obtained, on the average, in 838% of all the discs A difference of one grade occurred in 159% and a difference of two or more grades in 13% of all the cases Conclusion Disc degeneration can be graded reliably on routine T2-weighted magnetic resonance images using the grading system and algorithm presented in this investigation

Magnetic resonance classification of lumbar intervertebral disc degeneration.

Herniated intervertebral disc tissue has been shown to produce a number of proinflammatory mediators and cytokines, but there have been no similar studies using discs from patients with discogenic low back pain. We have compared the levels of production of interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E2 (PGE2) in disc tissue from patients undergoing discectomy for sciatica (63) with that from patients undergoing fusion for discogenic low back pain (20) using an enzyme-linked immunoabsorbent assay. There was a statistically significant difference between levels of production of IL-6 and IL-8 in the sciatica and low back pain groups (p < 0.006 and p < 0.003, respectively). The high levels of proinflammatory mediator found in disc tissue from patients undergoing fusion suggest that production of proinflammatory mediators within the nucleus pulposus may be a major factor in the genesis of a painful lumbar disc.

Intervertebral discs which cause low back pain secrete high levels of proinflammatory mediators.

The prevalence, validity and reliability of high-intensity zones in the annulus fibrosus seen on T2-weighted magnetic resonance images of patients with intractable low-back pain were determined. This sign was readily recognized by two independent observers. It occurred in 28% of 500 patients undergoing magnetic resonance imaging for back pain. The presence of a highintensity zone correlated significantly with the presence of Grade 4 annular disruption and with reproduction of the patient's pain. Its sensitivity as a sign of either annular disruption or pain was modest but its specificity was high, and its positive predictive value for a severely disrupted, symptomatic disc was 86%. This sign is diagnostic of painful internal disc disruption.

High-intensity zone: a diagnostic sign of painful lumbar disc on magnetic resonance imaging.

Procedure Appropriateness Category Relative Radiation Level Radiography area of interest Usually Appropriate Varies CT area of interest with IV contrast Usually Not Appropriate Varies CT area of interest without and with IV contrast Usually Not Appropriate Varies CT area of interest without IV contrast Usually Not Appropriate Varies FDG-PET/CT whole body Usually Not Appropriate ☢☢☢☢ MRI area of interest without and with IV contrast Usually Not Appropriate O MRI area of interest without IV contrast Usually Not Appropriate O Bone scan whole body Usually Not Appropriate ☢☢☢ US area of interest Usually Not Appropriate O

The American College of Radiology. ACR Appropriateness Criteria project.

The sequelae of disk degeneration are among the leading causes of functional incapacity in both sexes and are a common source of chronic disability in the working years Disk degeneration involves structural disruption and cell-mediated changes in composition Mechanical, traumatic, nutritional, and genetic factors all may play a role in the cascade of disk degeneration, albeit to variable degree in different individuals The presence of degenerative change is by no means an indicator of symptoms, and there is a very high prevalence in asymptomatic individuals The etiology of pain as the symptom of degenerative disease is complex and appears to be a combination of mechanical deformation and the presence of inflammatory mediators The role of imaging is to provide accurate morphologic information and influence therapeutic decision making A necessary component, which connects these two purposes, is accurate natural history data Understanding the relationship of etiologic factors, the morphologic alterati

Lumbar degenerative disk disease.

The authors reviewed magnetic resonance (MR) images of 474 consecutive patients referred for lumbar spine MR imaging. Type 1 changes (decreased signal intensity on T1-weighted spin-echo images and increased signal intensity on T2-weighted images) were identified in 20 patients (4%) and type 2 (increased signal intensity on T1-weighted images and isointense or slightly increased signal intensity on T2-weighted images) in 77 patients (16%). In all cases there was evidence of associated degenerative disk disease at the level of involvement. Histopathologic sections in three cases of type 1 change demonstrated disruption and fissuring of the end plates and vascularized fibrous tissue, while in three cases of type 2 change they demonstrated yellow marrow replacement. In addition, 16 patients with end-plate changes documented with MR were studied longitudinally. Type 1 changes in five of six patients converted to a type 2 pattern in 14 months to 3 years. Type 2 changes in ten patients remained stable over a 2-3...

Degenerative disk disease: assessment of changes in vertebral body marrow with MR imaging.

Thirty patients with failed back surgery syndrome were studied to evaluate the effectiveness of magnetic resonance (MR) imaging with gadolinium-diethylenetriaminepentaacetic acid/dimeglumine (Gd-DTPA) in differentiating postoperative epidural fibrosis (scar) from recurrent disk herniation. Pre- and postcontrast MR images were interpreted without access to other diagnostic, surgical, or pathologic findings. Seventeen patients had surgical and pathologic correlation of the MR findings at 19 disk levels. The precontrast studies had a sensitivity, specificity, and accuracy of 100%, 71%, and 89%, respectively. The enhanced MR studies correctly depicted the character of abnormal epidural soft tissue in 17 patients at all 19 levels. Scar showed heterogeneous enhancement on the early T1-weighted spin-echo images obtained within 10 minutes after contrast material administration. Herniated disk did not show significant enhancement on the early studies but showed variable degrees of enhancement on delayed images in ...

P. M. Steinberg

Papers

Degenerative disk disease: assessment of changes in vertebral body marrow with MR imaging.

Lumbar spine: postoperative MR imaging with Gd-DTPA.