Location, length, and enhancement: systematic approach to differentiating intramedullary spinal cord lesions.

PURPOSE: Intramedullary spinal cord abnormalities are often challenging to diagnose. Spinal cord biopsy is a high-risk procedure with the potential to cause permanent neurological injury. Magnetic resonance imaging is the modality of choice for diagnosis and preoperative assessment of patients with spinal cord abnormalities. The radiologist's ability to narrow the differential diagnosis of spinal cord abnormalities has the potential to save patients from invasive approaches for diagnosis and also guide appropriate management.

APPROACH/METHODS: This article will provide a systematic approach to the evaluation of intramedullary spinal cord lesions-with emphasis on location, length and segment distribution, and enhancement pattern-to help narrow the differential diagnosis. In doing so, we will review various spinal cord pathologies, including demyelinating and metabolic conditions, neoplasms, and vascular lesions. Although intramedullary spinal cord abnormalities can be a challenge for the radiologist, a systematic approach to the differential diagnosis with a focus on lesion location, cord length and segment involvement, as well as enhancement pattern, can greatly help narrow the differential diagnosis, if not synch the diagnosis. This strategy will potentially obviate the need for an invasive approach to diagnosis and help guide treatment.

TEACHING POINTS: • Imaging diagnosis of intramedullary spinal cord lesions could obviate cord biopsy. • Evaluation of cord lesions should focus on location, length, and enhancement pattern. • In demyelination, the degree of cross-sectional involvement is a distinguishing feature.