Study Design. Systematic review.
Objective. We sought to conduct a systematic review to examine the role of magnetic resonance imaging in predicting outcomes after surgery and to evaluate the evidence currently available critically.
Summary of Background Data. Degenerative compressive myelopathy is a common clinical problem associated with adverse health outcomes. Although a number of studies have investigated the association between preoperative magnetic resonance imaging characteristics and outcomes after surgery for degenerative compressive myelopathy, the conclusions of these studies have often yielded differing results.
Methods. Articles examining the predictive value of magnetic resonance imaging were obtained from MEDLINE, EMBASE, and PubMed databases (1980–2011). Thirty publications that met the inclusion criteria were reviewed. Two reviewers independently assessed each study regarding the level of evidence (using the criteria proposed by Sackett) and methodological quality based on revised Cochrane quality assessment checklist.
Results. Three excellent, 1 good, and 10 poor quality studies assessed cord compression—transverse area (4), compression ratio (5), and anteroposterior diameter (1). Relationship between signal intensity (SI) changes and surgical outcomes were reviewed by 28 studies—8 excellent, 9 good, and 13 poor quality studies. SI changes within the spinal cord included the presence of SI on T2-weighted image (WI) (17), area of SI on T2WI (8), degree of SI on T2WI (5), presence of SI on both T1-/T2WI (2), SI ratio on T2WI (2), and the position of SI on T2WI (1).
Conclusion. Based on a combination of excellent and good quality studies, transverse area correlates with recovery ratio but not with postoperative functional score assessed by Japanese Orthopaedic Association/modified Japanese Orthopaedic Association scores. SI changes defined by (1) its presence on T2WI, (2) its extent (focal or multisegmental), (3) its brightness, and (4) its presence on both T1-/T2WI can predict surgical outcomes in degenerative compressive myelopathy.
Level of Evidence: 2
Systematic review to evaluate the quality of evidence addressing the role of magnetic resonance imaging (MRI)-based assessment of cord compression in predicting surgical outcomes in patients with degenerative compressive myelopathy. Quantitative MRI parameters and signal intensity changes in the cord can reliably predict postoperative outcomes.
*Krembil Neuroscience Center, Toronto Western Hospital, Toronto, Canada
†Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada
‡Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network and Departments of Physical Therapy and Graduate Departments of Rehabilitation Science, Health Policy, Management and Evaluation and the Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
§Division of Neurosurgery, Hospital for Sick Children, University of Toronto, Ontario, Canada
¶Division of Genetics and Development, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada; and
‖Krembil Chair, Neural Repair and Regeneration, Head, Spinal Program, University Health Network, Toronto, Ontario, Canada.
Address correspondence and reprint requests to Michael G. Fehlings, MD, PhD, FRCSC, FACS, Krembil Chair in Neural Repair and Regeneration, The Toronto Western Hospital, University Health Network, Room 4W-449, 399 Bathurst St, Toronto, Ontario M5T 2S8, Canada; E-mail: firstname.lastname@example.org
Acknowledgment date: December 21, 2011. First revision date: July 3, 2012. Second revision date: January 16, 2013. Third revision date: March 12, 2013. Acceptance date: March 15, 2013.
The manuscript submitted does not contain information about medical device(s)/drug(s).
AOSPINE North America and the Ontario Neurotrauma Foundation Scholarship funds were received to support this work.
No relevant financial activities outside the submitted work.