Intradural disk herniation with CT appearance of gas collection.

Intradural disk rupture has been reported [1-5] . In most cases disk herniation in the lumbar region occurs on one side or the other of the strong posterior longitudinal ligament; seldom is the central part of the ligament perforated . Very rarely , a disk fragment ruptures through the anterior aspect of the spinal dura to project intrathecally [1] . Continued negative pressure is not necessary to retain gas within a disk [6] . Consequently, gas formed in the nucleus pulposus may persist even if the latter herniates into the spinal canal. Intradural rupture of a disk fragment with the computed tomographic (CT) appearance of an intraspinal gas collection has not been reported . In the case we report , reparative neuromalike tissue reactions had developed around a nerve root to which the disk fragment appeared to be firmly attached [7] . CT provided very important information