Sagittal contrast MRI in T1 weighting: A medullar bone oedema is seen on either side of the L5-S1 disk. Small collections surround L5-S1 with the largest being 20mm in diameter located on the left psoas muscle with a wall that was intensified by the contrast. This abscess extends posteriorly to the anterior peridural space, the lumbar vertebral bodies, and the last thoracic vertebra.