Intradural intraneural hemorrhagic cyst resulting in progressive cauda equina syndrome after anticoagulation therapy

STUDY DESIGN.: Case report. OBJECTIVE.: To report a case of lumbar intraneural hemorrhagic cyst after anticoagulation therapy that caused progressive radiculopathy and cauda equina syndrome. The possible pathogenic mechanism, associated diseases, and treatment options are discussed. SUMMARY OF BACKGROUND DATA.: Various pathological processes can cause progressive cauda equina syndrome. However, there have been no reports of progressive cauda equina syndrome due to compression from an intraneural hemorrhagic cyst after anticoagulation therapy. METHODS.: A case of lumbar intradural intraneural hemorrhagic cyst with progressive cauda equina syndrome after anticoagulation therapy is presented. RESULTS.: A 42-year-old-female patient complained at presentation of progressive bilateral lower extremity radiating pain, numbness, and urinary difficulty during the previous 2 months. Lumbar magnetic resonance imaging revealed an L1 cystic lesion with marked mass effect on the surrounding nerve roots. Complete drainage and excision of the lesion was performed, which resulted in excellent postoperative symptoms relief. Pathological examination revealed no definite neoplastic process except some nerve fibers with hemosiderin stain along the cyst wall. On the basis of a combination of intraoperative findings and pathology, an intradural intraneural hemorrhagic cyst that developed after systemic anticoagulation therapy was diagnosed. CONCLUSION.: This is the first report of an intradural intraneural hemorrhagic cyst causing progressive cauda equina syndrome due to anticoagulation therapy. Surgical excision of the cyst is the definite treatment of choice.