- Arise from or partially embedded within the ligamentum flavum
- Seldom seen
- Related to necrosis or myxoid degeneration in a hypertrophied ligamentum flavum
- Chronic degenerative changes followed by repetitive hemorrhages will form degenerative cysts
- These small cysts aggregate to form a single large cyst
- Typical location: L4-5
- Extradural intraspinal mass in close relation to ligamentum flavum
- No rim calcification (unlike juxtafacet cysts)
- Sharply delineated
- Round to ovoid
- High T2 signal with low intensity rim. Rim enhances with gadolinium
Baker, James K., and Gregory W. Hanson. “Cyst of the ligamentum flavum.” Spine 19.9 (1994): 1092-1094.
Cakir, Ertugrul, et al. “Ligamentum flavum cyst.” Journal of Clinical Neuroscience 11.1 (2004): 67-69.