Unrecognized dural tear during percutaneous endoscopic lumbar surgery confirmed with myelography

Iatrogenic dural tear is usually recognized during the surgery. We describe a rare case of unrecognized dural tear caused by percutaneous endoscopic lumbar surgery at another hospital clearly confirmed with dynamic myelography. Although magnetic resonance imaging of the lumbar spine showed no obvious fluid collection suggesting dural tear, dynamic myelography revealed leakage of intradural subarachnoid contrast medium along root sleeve into the intervertebral disc space. In the setting of endoscopic spine surgery, incidental dural tear might be overlooked due to the narrow and fluid-filled surgical field. Dynamic myelography is useful to evaluate the precise condition caused by unrecognized dural tear.