Chiari malformation, back pain. There is a relatively small posterior fossa and there is platybasia with a somewhat hypoplastic clivus. There are low-lying, pointed cerebellar tonsils that extend nearly 20 mm inferior to the foramen magnum, resulting in marked impendence to cerebrospinal fluid flow in the craniocervical junction region and mass-effect upon the cervicomedullary tissues. There is mild prominence of the upper cervical spinal cord central canal. The rest of the spinal cord displays normal signal and morphology. The vertebral column alignment is within normal limits. The vertebral body and disc space heights are preserved. The vertebral bone marrow signal is unremarkable. There are mild disc bulges in the lumbar spine, but no significant spinal canal or neural foraminal stenoses. The paravertebral soft tissues are unremarkable.
1. Dysmorphic posterior skull base as low-lying, pointed cerebellar tonsils that extend nearly 20 mm inferior to the foramen magnum, resulting in marked impendence to cerebrospinal fluid flow in the craniocervical junction region2. Apparent mild upper cervical spinal cord syrinx.