腰部硬膜下腔ヘルニアの２症例

Abstract

Since the first discription of intrathecally prolapsed disc by Dan dy (1942), the papers have been rarely reported. We have experienced intradural disc prolapse in two cases out of 1556 cases with surgical in tervention for the lumbar disc herniation. 86 cases found in litera tures were reviewed. Intrathecally prolapsed disc on the average acc ounted for about 0.2% according to literatures. Intradural disc prolapse was mostly encountered at the L4/5 disc level, and more frequently localized at the upper lumbar disc (L1/2-L3/4) levels than commonly experienced herniation. The first patient in this series was difficult to be differentiated from cauda equina tumor in myelogram and magnetic resonance imaging. Because intradural herniated disc in the first case was enhanced with Gd-DTPA. But retrospectively, iso-intensity lesion in intradural space was mostly valuable as the diagnostic examination. The second patient showed the myelogram like a massive epidural disc prolapse. That is, the myelogram of both patients revealed a regularly marginated manifestation, this feature was different from the previously reported cases. And the second case was found at an uncommon L5/S disc level postoperatively.Anterior dura mater had fastly adhered with posterior longitudinal ligament in these two cases.