Intradural Lumbar Disc Herniation: Magnetic Resonance Imaging Findings and Surgical Results with a Literature Review
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Tae Seok Jeong, Yong Ahn, Sang Gu Lee, Woo Kyung Kim, Seong Son |
Department of Neurosurgery, Gil Medical Center, Gachon University College of Medicine, Incheon, Korea |
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Abstract |
Objective Intradural lumbar disc herniation is a rare type of disc herniation. Preoperative diagnosis is difficult, and intradural disc herniation is only confirmed during surgery in most cases. Therefore, this report was to investigate magnetic resonance(MR) imaging features of intradural lumbar disc herniation that can aid in preoperative diagnosis.
Methods We analyzed five patients treated surgically for intradural lumbar disc herniation. MR imaging findings were evaluated with various factors as follows: herniation type, enhancement patterns, percent canal compromise, migration, and disc degeneration grade. Surgical outcome was evaluated with visual analog scale(VAS) for pain. Neurological deficit was checked one year after surgery, and postoperative complications were also confirmed. Intraoperative findings were evaluated to compare with preoperative MR imaging.
Results The herniated intradural disc had the common feature of the fragment with a sharp edge in four of five cases, and it showed feature of large mass with irregular margin in one case. Gadolinium-enhanced MR image showed ring enhancement of the herniated disc in all of two cases using contrast. Mean percent canal compromise was 50.8%. Mean VAS was 7.0 preoperatively and 2.2 after surgery. There were postoperative complications in two cases: cerebro- spinal fluid leak and transdural nerve root entrapment.
Conclusion Intradural lumbar disc herniation is rare, but it is hard to diagnose preoperatively. Characteristic findings on MR imaging such as high canal compromise and long anterior-posterior diameter with a sharp edge may help preoperative diagnosis of intradural disc herniation. |
Key Words:
Diagnosis, Intradural disc, Intervertebral disc displacement, Lumbar vertebrae, Magnetic resonance imaging |
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