Abstracto

Imaging of spinal cord compression

Daniela Distefano and Alessandro Cianfoni

A wide spectrum of conditions may compress the spinal cord: degenerative disease, disc herniation and neoplasms are the most common causes; other conditions include trauma, epidural abscess and hematoma. The role of imaging is to establish a radiological diagnosis, to distinguish intrinsic spinal cord disease from extrinsic compression, to define mechanical spine stability and to evaluate the integrity of neural tissue. Clinical presentation, variable in severity and patterns of progression, influences the imaging approach. Imaging is required to assess osseous structures and soft tissues. The need to image ‘across anatomical compartments’ usually requires more than one imaging technique. Multidetector CT is the first-line imaging modality in acute spine trauma. MRI is the best imaging modality to assess soft tissues, image the extradural, intradural and spinal cord compartments. MRI needs to be implemented with fatsuppression techniques applied to T2- and contrast-enhanced T1-weighted sequences. MRI helps predict neurological recovery, providing macroscopic information including both reversible and irreversible histologic changes. Diffusion tensor imaging enables depiction of microstructural changes in the compressed spinal cord, which could further predict tissue viability, and functional prognosis. The role of CT myelography is reserved to selected cases, when MRI is not feasible or results are unclear but, intrathecal injection of contrast from below and above the compression level might be necessary to overcome the diagnostic limitations imposed by a myelographic block. This article summarizes the capabilities and limits of different imaging modalities in the spinal cord compression scenario, suggesting technical imaging protocols and diagnostic pathways, and discusses imaging aspects of various causes of spinal cord compression, following an organization based on their anatomical compartment of origin: osseous, epidural or intradural.