Fig. 2

Magnetic resonance imaging of the thoracolumbar spine of case no. 8 (top row) and 14 (bottom row) who display intra-dural spinal cord compression. From left to right; a = T2-weighted sagittal MRI, b = T2-weighted transverse MRI, c = CISS sequence reconstructed in sagittal plane, d = CISS sequence reconstructed in dorsal plane. In case 8, intra-dural spinal cord compression appears to be associated with an expansion of the dorsal arachnoid space, consistent with spinal arachnoid diverticula. CISS imaging highlights this CSF accumulation without apparent attachment of the dura to the pia (dashed line). In case 14, in a transverse plane (lower row image b) the spinal cord appears to develop a ‘stellate’ appearance with multiple hypo-intense bands that cross the arachnoid space (highlighted with short arrows on image b). At the corresponding level on CISS imaging (lower row, images c and d, dashed line) the hypo-intense bands appear lateral to the compressed spinal cord (level marked with dashed line) with an appearance reminiscent of the original description of ‘constrictive myelopathy’ [4]