Radicular Compression by Intraspinal Epidural Gas Bubble Occurred in Distant Two Levels after Lumbar Microdiscectomy

The authors report a case of symptomatic epidural gas accumulation 2 weeks after the multi-level lumbar surgery, causing postoperative recurrent radiculopathy. The accumulation of epidural gas compressing the dural sac and nerve root was demonstrated by CT and MRI at the distant two levels, L3-4 and L5-S1, where vacuum in disc space was observed preoperatively and both laminectomy and discectomy had been done. However, postoperative air was not identified at L4-5 level where only laminectomy had been done in same surgical field, which suggested the relationship between postoperative epidural gas and the manipulation of disc structure. Conservative treatment and needle aspiration was performed, but not effective to relieve patient's symptoms. The patient underwent revision surgery to remove the gaseous cyst. Her leg pain was improved after the second operation.

Symptomatic Epidural Gas-containing Cyst from Intervertebral Vacuum Phenomenon

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.

Symptomatic Spinal Epidural Gas-Containing Cystic Lesions: Reports of 2 Cases

Symptomatic spinal epidural gas-containing cystic lesion is a rare clinical disease entity. We recently experienced two cases of symptomatic epidural gas-containing cysts that were the main cause of the patients?radiculopathy and the cysts were removed surgically. These lesions were actually gas containing ruptured disc herniations from the vacuum discs at the same level. We report herein on the radiological findings along with conducting a review of the related literature.