STILL JUST NOTES, UNDER CONSTRUCTION
When obtaining an MRI of the thoracic spine for evaluation of a spinal cord syndrome, the well-known phenomenon of false localizing sensory levels should be kept in mind. Consider including the cervical spinal cord so that false negative results caused by misleading localizing signs (e.g. a thoracic sensory level caused by a cervical lesion) can be avoided (1-3).
A study of 324 episodes of malignant spinal cord compression found that clinical signs were very unreliable indicators of the level of compression. Only 53 patients (16%) had a sensory level that was within 3 vertebral levels of the level of compression demonstrated on MRI. Pain (both midline back pain and radicular pain) was a similarly poor predictor of the level of compression (4).
The difference between the false localizing sensory level and the level of the cervical lesion can be 11 segments (1,3) . False localizing sensory levels in spinal cord syndromes result from remote higher levels of a compressive lesion or from vascular compromise due to variants of the blood supply.
(1) Hellmann MA, et al. Clin Neurol Neurosurg 2013;115(1):54-6.
(2) Frohman EM, et al. N Engl J Med 2010; 363:564-572.
(3) Rousseff RT, et al. NeuroRehabilitation 2006;21(3):219-22.
(4) Summers D, et al. Br J Radiol 2001;74:977-8.