Dorsal cervical spinal arachnoid cyst (Type III) presenting with dorsal column dysfunction: A case report.

CONTEXT: Spinal arachnoid cysts are usually asymptomatic and discovered incidentally. Expansion of the cyst, whether acute, subacute or chronic, leads to neural compression resulting in radicuopathy and/or myelopathy.

FINDINGS: This case report is of a patient who presented primarily with posterior column dysfunction,subacute in onset and rapidly progressing. Images of the cervical spine showed a dorsal arachnoid cyst, causing significant cord compression and signal changes in the cord, with no scalloping of the vertebrae.

CONCLUSION

The author explains the mechanism of rapid expansion of an asymptomatic spinal arachnoid cyst, causing neural compression leading to fast progression of neurological deficits. The dorsal location of the cyst, explain the absence of radiculopathy, which is a common presenting feature of ventrally located intradural arachnoid cyst.