Intradural extramedullary spinal epidermoid cyst: a narrative review of predisposing factors, surgical challenges, and outcomes.

Background: Spinal epidermoid cysts (SECs) are rare, benign, and slow-growing lesions that can lead to progressive neurological deficits. Due to their rarity, there is limited consolidated data on their clinical features and surgical outcomes. This review aims to synthesize existing evidence to better understand the predisposing factors, clinical presentations, management strategies, and outcomes of intradural extramedullary SECs. Methods: A review of 29 previously published cases with confirmed histopathological diagnoses of intradural extramedullary SECs was conducted. Extracted data included patient demographics, predisposing factors, clinical symptoms, imaging findings, surgical approaches, intraoperative challenges, and postoperative outcomes. Results: Lumbar puncture was identified as the most common predisposing factor (27.59%), followed by prior spinal surgery and congenital anomalies (13.79% each), while 41.38% of cases had no identifiable cause. The thoracic and lumbar regions were the most frequently affected sites. The predominant symptoms were paraparesis (34.48%) and back pain (31.03%), with sensory disturbances, urinary incontinence, and lumbago-sciatica each occurring in 17.24% of cases. Gross total resection (GTR) was performed in 75.86% of cases, yielding favorable outcomes in most patients: complete recovery in 65.52%, significant improvement in 17.24%, and minimal improvement in 10.34%. Postoperative complications were uncommon, with 82.76% of patients experiencing none. Key surgical challenges included cyst adhesion to neural elements, risk of rupture, and difficulties in revision procedures. Conclusion: Early diagnosis, advanced imaging, and advanced surgical technique are essential for optimal management of spinal epidermoid cysts. GTR remains the preferred approach, offering favorable neurological outcomes with a low complication profile.