Imaging the post-operative spine - are we united in where we stand?

Transcription

1 Imaging the post-operative spine - are we united in where we stand? Poster No.: C-2424 Congress: ECR 2015 Type: Authors: Keywords: DOI: Scientific Exhibit J. Kumaraguru, N. Kandasamy, D. A. Elias, J. M. U-King-Im; London/UK Quality assurance, Patterns of Care, Technical aspects, MR, CT, Neuroradiology spine, Musculoskeletal spine, CNS /ecr2015/C-2424 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 9

2 Aims and objectives Interpreting the appearances post surgery (laminectomy / discectomy) in the lumbar spine can be at times challenging. Gadolinium enhanced images may help identify or discriminate common complications i.e residual / recurrent disc, post surgical granulation tissue / epidural fibrosis and discitis / infective collections. A short survey was performed to see if at all there is a consensus with regards to the requirement for Gadolinium post laminectomy / discectomy Images for this section: Fig. 1: Ax T2W image at L5/S1 shows a right sided laminectomy (orange arrow) and the right S1 nerve root sleeve (purple arrow). Note the heterogeneous T2 intermediate appearance of the epidural fat (" dirty fat") within the right lateral recess. Page 2 of 9

3 Fig. 2: Non-contrast Ax T1W image at L5/S1 shows T1 hypointense material (red arrow) replacing the epidural fat within the right lateral recess. The T1 hypointensity is contiguous with the nerve root sleeve which cannot be completely delineated and also continues across the laminectomy defect. Page 3 of 9

4 Fig. 3: Post contrast Ax T1W image corresponding to image 2 shows avid enhancement of the previously shown T1 hypointense material which is shown to partially encase the right S1 nerve root sleeve (purple arrow). The further more laterally sited tiny nonenhancing component (red arrow) is a sequestrated disc fragment which was confirmed at surgery. Page 4 of 9

5 Methods and materials A paper questionnaire was sent to radiology consultants (neuroradiologists, musculoskeletal radiologists and general radiologists who routine report MRI spine examinations) and their response collected. Responses were collected from 19 radiologists. The response rate was 100% as the survey questionnaire was intentionally designed to be clear and take minimal time to respond. Sample survey questionnaire used for this pilot study is as shown in Fig.1. Images for this section: Page 5 of 9

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7 Fig. 4: Survey Questionnaire Page 7 of 9

8 Results Responses obtained showed a wide variation with no consensus within the department or between departments (Neuroradiology and musculoskeletal radiology). All respondents mentioned that the duration they had outlined was based on personal experience or an educated / random guess. It is worth noting that no respondent mentioned that the duration was evidence base, clearly highlighting the paucity of evidence in this regard. The period beyond which a contrast enhanced examination would not be of help varied from 1 year to indefinite. Moreover, the responses obtained also showed that there was no consensus amongst radiologists within the same department and within the hospital with regards to a set departmental policy. The majority said there was no agreed departmental policy. Conclusion It is clear that the varied response in the survey with a lack of reasonable consensus highlights the lack of robust evidence in this regard. This in turn also highlights the fact that imaging the lumbar spine post discectomy is never straighforward and there are a lot of confounding factors which include initial presentation, surgical approach and techniques and the fact that inflammatory response post surgery is varied as well. The only study to our knowledge which had taken the temporal factor into account [4] mentions that the intensity of enhancement of the scar tissue was maximum upto 9 months post surgery but does not give an upper limit as to how long epidural scar tissue would enhance. One can envisage that the intensity of enhancement would then gradually decrease with time. With the evolution of the granulation tissue, assuming that there is no signifcant change in bulk between 6 months and 1 year [5] perhaps there is a noticeable difference in the intensity of contrast enhancement. Whether this reduction in intensity of enhancement decreases the specificity of differentiating disc from granulation tissue needs to be seen. Personal information Dr. Janani Kumaraguru MBBS BA FRCR, Specialty Registrar in Radiology (Musculoskeletal and trauma), Kings College Hospital, London UK jan@doctor.com Dr Nagachandar Kandasamy MBBS DMRD FRCR, Consultant Neuro Radiologist (Diagnostic and Interventional), Kings College Hospital, London UK Page 8 of 9

9 Dr David Elias MBBS MRCP, Consultant Musculoskeletal Radiologist, Kings College Hospital, London UK Dr Jean Marie U-King-IM, Consultant Neuroradiologist, Kings College Hospital, London UK References 1) MRI of the post-operative lumbar spine. Van Goethem JW, Parizel P, Jinkins R. Neuroradiology, 44: ,2002 2) The post-surgical lumbosacral spine. MRI evaluation following intervertebral disk surgery, surgical decompression, intervertebral bony fusion and spinal instrumentation. Jinkins R., Van Goetem JW.Radiol Clin North Am 39:1-29,2001 3) Early postoperative gadolinium-dtpa-enhanced MRimaging after successful lumbar discectomy. VandeKelftEJ, vangoethemjw, delaportec, VerlooyJS. Br J Neurosurg 1996;10: ) Lumbar spine following successful surgical discectomy. Deutsch AL, Howard M, Dawson EG, et al. Magnetic resonance imaging features and implications. Spine 1993;18: ) Time dependant scar enhacement in magnetic resonance imaging of the postoperative lumbar spine. Glickstein MF, Sussman SK. Skel Radiol 1991;20: )The postoperative lumbar spine: evaluation of epidural scar over a 1-year period. Ross JS, Obuchowski N, Zepp R. AJNR Am J Neuroradiol 1998;19: Page 9 of 9