Wilson JR, Tetreault LA, Kim J, et al. State of the Art in Degenerative Cervical Myelopathy: An Update on Current Clinical Evidence. Neurosurgery. 2017;80(3S):S33-S45. doi:10.1093/neuros/nyw083.
Degenerative cervical myelopathy (DCM) is used to describe myelopathy resulting from degenerative pathology in the cervical spine including spondylosis, degenerative disc disease, ossification of the posterior longitudinal ligament (OPLL), and ossification of the ligamentum flavum. The authors provide a wide-ranging overview of the state of the art in degenerative cervical myelopathy, with a focus on updating the spine surgeon on the current evidence surrounding pathophysiology, natural history, imaging, outcome measures, and outcome prediction tools. They also provide an overview of the evidence for surgical vs. non–operative management, and a summary of the literature regarding the most commonly used approaches to the cervical spine.
The pathophysiology of DCM includes both static and dynamic factors. Static factors result from congenital stenosis or acquired stenosis secondary to spondylosis and disc degeneration. Dynamic factors relate to exacerbation of spinal cord compression seen with physiological and, in the setting of degenerative subluxation, pathological motion of the cervical spine. In addition to physical compression, there is a reduction in blood supply leading to ischemia within the cord. Pathological features of DCM include gray and white matter degeneration, anterior horn cell loss, cystic cavitation, and Wallerian degeneration of the posterior columns adjacent to the site of compression.
There is also likely a secondary cascade of neuro–inflammation consisting of microglia activation and macrophage recruitment which occurs at the site of mechanical compression within the spinal cord. In the non–compressed non–myelopathic spinal cord, the blood-spinal cord-barrier is isolated from the peripheral immune system; however, chronic compression renders the cord susceptible to cell infiltration that may be involved in …
Zurawski J, Lassmann H, Bakshi R. Use of Magnetic Resonance Imaging to Visualize Leptomeningeal Inflammation in Patients With Multiple Sclerosis. JAMA Neurol. 2017;74(1):100. doi:10.1001/jamaneurol.2016.4237.
You are well aware that MS is a chronic demyelinating disease traditionally characterized by an initial relapsing-remitting clinical course and focal inflammatory lesions that have a predilection for the periventricular white matter. However, histopathologic and imaging studies have illustrated a more complex pathologic substrate involving cortical demyelination, gray matter atrophy, and meningeal inflammation. The authors evaluate the status and prospects regarding the emerging role of MR to visualize leptomeningeal enhancement (LME) in patients with MS and place these findings in the proper pathobiologic and clinical context.
Absinta et al (Absinta M, Vuolo L, Rao A, et al. Gadolinium-based MRI characterization of leptomeningeal inflammation in multiple sclerosis. Neurology. 2015;85(1):18-28.) found that LME was significantly more common than had been initially reported, and its presence was associated with patient age, disease severity, and clinical type of MS. The authors used high-resolution 3T 3-dimensional T2 FLAIR MRI with a voxel size of 1.0 × 1.0 × 1.0mm and postcontrast images obtained 10 minutes after gadolinium injection. They demonstrated LME in 74 of 299 patients with MS (24.7%) compared with only 1 of 37 (2.7%) age-matched controls with out MS. Perhaps of particular importance, LME was twice as frequent (33%) in patients with progressive forms of MS (present in 44 patients with secondary progressive MS) (SPMS) and 74 patients with primary progressive MS (PPMS) compared with those with relapsing-remitting (RR) disease (19%). Disease duration, and Expanded Disability Status Scale scores were associated with LME. Whole-brain and cortical atrophy were also associated with LME. There was no association between LME and WM lesion enhancement or WM lesion volume. Leptomeningeal enhancement topography abutted the pial surface on the cerebral convexity (19% …