Chiari decompression with thoracic syrinx: surveillance. There are postoperative findings related to Chiari decompression. The inferior cerebellar hemispheres extend to the level of the tip of the dens. There is intact cerebrospinal fluid fluid across the anterior neo-foramen magnum, but flow posteriorly appears to be blunted. There also appear to be fine low signal linear strands that extend from the mildly deformed posteroinferior cerebellar hemispheres to the overlying dura. There is interval decrease in caliber of the thoracic syrinx, which now measures up to 2 mm in width. There is mild retroflexion of the dens. The vertebral column alignment is otherwise within normal limits. The vertebral body and disc space heights are preserved. The vertebral bone marrow signal is unremarkable. There is no significant spinal canal stenosis. There is no evidence of pseudomeningocele.
1. Postoperative findings related to Chiari decompression with suggestion of adhesion formation between the cerebellum and overlying dura and mild retroflexion the dens.2. Marked interval decrease in size of the thoracic syrinx. 