General
- These rare CSF containing thin walled cysts may exist as diverticulae of arachnoid, dura, or the nerve root sheath within the lumbar spine
- Usually incidental findings on MRI.
Classification: Nabor
- Type 1— Extradural meningeal cyst without neural tissue
- Type 1a— Extradural spinal arachnoid cyst
- Type 1b— Sacral meningocele
- Type 2— Extradural meningeal cyst containing neural tissue (Perineural/Tarlov cysts)
- Type 3— Intradural arachnoid cysts