Age / Sex : 80 / F

Chief complaint : Gait disturbance, upper and lower limb motor weakness


What is your diagnosis?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer)

Courtesy :  김동균 (Dong Kyun Kim), 서울성모병원 (Seoul St. Mary’s Hospital)

Dorsal arachnoid web

Discussion

Disease definition
: the presence of a thickened band of arachnoid over the dorsal aspect of the cord

Findings
1. Ventral displacement of thoracic spinal cord (possible scalpel sign) and expansion of dorsal CSF space (6 mm in maximal AP diameter) at T4-T5 level with resultant focal syringomyelia.
2. The presence of pulsation artifacts on MR and uniform contrast filling within dorsal CSF space on myelography, which exclude the possibility of (non-communicating) arachnoid cyst.
3. Preserved anterior CSF space on myelography, which excludes the possibility of ventral cord herniation.

References
Dorsal Thoracic Arachnoid Web and the “Scalpel Sign”: A Distinct Clinical-Radiologic Entity, M.A. Reardon, American Journal of Neuroradiology May 2013, 34 (5) 1104-1110