[Percutaneous treatment of a gas containing epidural pseudocyst: an uncommon cause of sciatica].

Gas containing epidural pseudocyst is a rare cause of lumbar radicular compression. We present the case of a 42 year old woman presenting with right L5 radicular pain. CT showed vacuum phenomenon and a gas containing epidural pseudocyst compressing the right L5 root. Resolution of radicular pain occurred following CT guided aspiration and steroid injection. The patient remained asymptomatic at one year follow-up.