Gas-filled intradural cysts of the lumbar spine and the possible pathogenesis.
BACKGROUND
There have only been four reports of gas-filled intradural cysts, and the pathogenesis is unknown.


OBJECTIVE
To document the radiologic and histopathologic features of gas-filled intradural cysts and to discuss the pathogenesis with a review of the literature.


METHODS
Case report.


METHODS
A 67-year-old woman, admitted to our institute, presented with severe right thigh pain. On admission to the institute, enhanced magnetic resonance imaging, showed a cystic lesion in the spinal canal at the L2-L3 level, with an intensity suggesting the presence of gas. An enhanced region around the cyst was noted. Computed tomography after discography also revealed a water-soluble contrast filled the subarachnoid space and area around the cyst, but not inside.


RESULTS
The cyst was surgically resected. One of the nerve roots was firmly adherent to the gas-filled cyst. The cyst wall comprised fibrous tissue, including small granulations and herniated disc material.


CONCLUSIONS
Gas-filled intradural cysts are rare. The pathogenesis appears to involve gas in a degenerated intervertebral disc, and spontaneous absorption of herniated disc material.
Sei
Akira
A
Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Kumamoto University, Honjo, Japan. a1203ki@fc.kuh.kumamoto-u.ac.jp
Mizutamari
Masaya
M
Fujimoto
Toru
T
Taniwaki
Takuya
T
Mizuta
Hiroshi
H
D000368:Aged; D003560:Cysts / Q000209:etiology* / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications* / Q000601:surgery; D008159:Lumbar Vertebrae / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging