title: Symptomatic Epidural Gas-containing Cyst from Intervertebral Vacuum Phenomenon.
abstract: Vacuum disc phenomenon is a collection of gas in the intervertebral disc space but rarely causes nerve compression. However, some rare type of vacuum phenomenon in the spinal canal may bring about posterior gas displacement within the epidural space. The authors describe two patients with symptomatic epidural gas-containing cyst that seem to be originating from vacuum phenomenon in the intervertebral disc, causing lumbosacral radiculopathy. Radiographic studies demonstrated intervertebral vacuum phenomenon and accumulation of gas in the lumbar epidural space compressing the dural sac and the nerve root. The nerve root in both patients was compressed by gas containing cyst that was surrounded by thin walled capsule separable from the gaseous degenerated disc space. The speculative mechanism of the nerve root compression is discussed. The possibility of gas containing cyst should be considered in case of the nerve root compression in which epidural gas is present.
authors.affiliation: Department of Neurosurgery, Ilsan Tntn Hospital, Goyang-si, Republic of Korea.
authors.forename: Sung Min
authors.initials: SM
authors.lastname: Yun
authors.affiliation: Department of Neurosurgery, Ilsan Tntn Hospital, Goyang-si, Republic of Korea.
authors.forename: Bumn Suk
authors.initials: BS
authors.lastname: Suh
authors.affiliation: Department of Neurosurgery, Ilsan Tntn Hospital, Goyang-si, Republic of Korea.
authors.forename: Jin Su
authors.initials: JS
authors.lastname: Park
keywords: Epidural gas-containing cyst; Nerve root compression; Vacuum phenomenon