The Challenge of Acute Non-Compressive Transverse Myelopathies

The term 'myelopathy' is used in this brief critical communication in preference to the commonly used term 'myelitis' to highlight that all cases of acute transverse myelopa-thies are not of infl ammatory origin. Indeed metabolic and vascular myelopa-thies, at times, do pose serious diagnostic problems and need different therapeutic approaches. The fi rst question, when faced with a clinically obvious transverse myelopathy, is whether it is really a 'new' 'acute' onset disease or an 'acute' exacerbation of a pre-existing unsuspected or unknown com-pressive or non-compressive myelopathic problem or perhaps a super addition of an acute non-compressive pathology on top of a mild pre-existing compressive problem. This issue needs to be settled at the very outset by careful history elicitation including family history and a very thorough neuro-radiological assessment. It must be stressed that spinal MRI must involve the entire spine with contrast and not limited only to the clinically suggestive level, not only to exclude unsuspected compressive pathology elsewhere but also to gauge the full length of the detected spinal lesion and exclude multiplicity of similar lesions elsewhere in the spinal cord. Even after careful radiological study, it may be sometimes diffi cult to differentiate infl ammatory lesions from intramedullary tumors, subtle extramedul-lary spinal cord compression with marked signal changes in the spinal cord at the same level or even extending above and below the level including hematoma and/or ischemic events. Imaging should preferably include the brain as well if an infl ammatory process is suspected. Establishing the etiology must also include cerebrospinal fl uid (CSF) analysis with immunological studies. Two recent reviews by Brinar et al. (2008) and Jacob and Weinshenker (2008) detail the differential diagnosis and of acute transverse myelopathies. The latter workers (Jacob and Weinshenker, 2008) have presented a very clinically oriented approach to fi nding the etiology based on anatomical localization of region of cord affected as revealed by thorough clinical and radiological means. They have classifi ed all intrinsic cord syndromes as – complete, Brown-Séquard syndrome , anterior cord syndrome, posterior cord syndrome, central cord syndrome, conus medullaris syndrome, cauda equina syndrome, and tractopathies. This appears to be an excellent approach. These authors (Jacob and Weinshenker, 2008) have also provided a 'fl ow chart' approach to mye-lopathies which seems to be very useful for the practicing clinician. Acute infl ammatory myelopathies can not solely be due to established autoimmune central nervous system (CNS) demyelinat-ing disorders …