Lumbar intraspinal extradural ganglion cysts

Abstract

The lumbar intraspinal epidural ganglion cyst has been a rare cause of the low back pain or leg pain. Ganglion cysts and synovial cysts compose the juxtafacet cysts. Extensive studies have been performed about the synovial cysts, however, very little has been known about the ganglion cyst. Current report is about two ganglion cysts associated with implicative findings in young male patients. We discuss about the underlying pathology of the ganglion cyst based on intraoperative evidences, associated disc herniation at the same location or severe degeneration of the ligament flavum that the cyst originated from in young patients.

Keywords: Ganglion cyst; Synovial cyst.

Fig. 1

Images of case 1. A and B : Preoperative sagittal T2-weighted magnetic resonance images showing a cystic lesion adjacent to the extruded disc material at L3-4. C : Preoperavie axial T2-weighted magnetic resonance image showing disc herniation medial to the cystic lesion. D : Intraoperative photograph showing a large cystic mass filled with dark fluid. E : Intraoperative photograph showing the herniated disc material (arrow) just above to the origin of the shrank cyst (arrow head). F : Photomicrograph shows thick fibromemebranous tissue with no lining epithelium. The thick walls show some fibroblasts and mild myxoid stromal change. H & E, original magnification×100. ^* : Nerve root. C : cyst, D : dura, L : lamina, SP : spinous process.

Fig. 2

Images of case 2. A and B : Preoperative sagittal magnetic resonance images showing a large round mass with high signal on T1-weighted image and heterogeneous high and low signal intensity on T2-weighted image. C : Preoperative axial T1-weighted magnetic resonance image showing the mass arising from the right ligamentum flavum of L5. D : Intraoperative photograph showing severely degenerated darkened yellow ligament (arrow). E : Intraoperative photograph showing fresh hematoma through an eye of a needle (arrow). F : Photomicrograph shows an irregular thick-walled cystic space with no lining epithelium. Old hemorrhagic areas are noted in the fibrotic stoma. H & E, original magnification×40.