 There are postsurgical changes centered at the L1-L2 level related to cord untethering. There is mild clumping of the left-sided cauda equina nerve roots at the L1-L2 level on the left which is not evident on prior study. No fluid collections in the posterior paraspinous soft tissues. There is no appreciable change in the appearance of the lower thoracic cord which is anteriorly positioned with mild concavity of the posterior cord contour at the T11 level. The conus more inferiorly is posteriorly positioned at the L1 level. There is no cord signal abnormality. No focal lesions involving the lumbar spinal canal. Prone images demonstrate appropriate ventral motion of the cauda equina nerve roots. However the conus remains posteriorly positioned in the spinal canal.Vertebral body heights and disc spaces in the thoracic and lumbar spine are unremarkable. There is no significant spinal canal or neural foraminal stenosis at any level.
1. Interval postsurgical changes related to cord untethering. There is unchanged appearance of the distal thoracic cord which remains anteriorly positioned in the thoracic spinal canal. Of note recent myelogram identified no filling defect to suggest an arachnoid cyst. Differential remains unchanged including anterior displacement of the cord related to adhesion or potentially cord herniation, or less likely early filling of an arachnoid cyst which was not evident on the myelogram.2. Prone images demonstrate appropriate ventral motion of the cauda equina nerve roots. The conus however remains posteriorly positioned, perhaps related to adhesion.3. Subtle clumping of the left-sided cauda equina nerve roots at the L1-L2 level compatible with postsurgical change/mild arachnoiditis.