Incidental diagnosis of intradural lumbar disc herniation during discography: a case report.

We describe an incidental finding of intradural lumbar disc herniation diagnosed radiographically during discography. A patient was referred to our center for discography with symptoms of worsening, intractable low back pain radiating to both hips and the left leg which was exacerbated when standing and walking. Magnetic resonance imaging of the lumbar spine revealed multiple disc bulges and lumbar facet arthroses with ligamentum flavum hypertrophy producing moderate central canal and lateral recess stenosis. Discography was performed at three levels (L3-4, L4-5, L5-S1). During fluoroscopically guided injection into L4-5 it was noted that contrast was not contained within the disc and spread intrathecally with a myelographic appearance. Computerized tomography confirmed accurate needle placement and a spread of contrast into the intrathecal space. To the best of our knowledge, this is the first report describing a finding of intradural disc herniation while performing discography. Physicians should be aware of this potential finding while performing this technique.