Lumbar intramedullary epidermoid cyst after myelomeningocele repair: case report and review of diagnostic imaging

Background. Intraspinal epidermoid cysts are rare lesions that may develop following spinal dysraphism surgery, such as myelomeningocele repair. These abnormalities are often associated with tethered cord syndrome, which presents significant diagnostic and therapeutic challenges. Epidermoid cysts can arise congenitally from ectodermal remnants or be acquired secondary to surgical implantation of epithelial elements. Early diagnosis and timely management are essential to prevent progressive neurological deterioration. Case presentation. We report a 3-year-old female who presented with left lower limb pain and gait disturbance three years after surgical repair of myelomeningocele. Neurological examination revealed increased tone, brisk reflexes, and a sensory level at T12. Magnetic resonance imaging (MRI) of the whole spine demonstrated a dorsal intramedullary cystic lesion at the L1–L3 level with characteristic T1 hypointensity, T2 hyperintensity, and diffusion restriction on diffusion-weighted imaging sequences. Management and outcome. The patient underwent laminectomy, complete surgical excision of the cyst, and detethering of the filum terminale. Postoperative recovery was uneventful, with full resolution of neurological deficits and neuropathic pain at six-month follow-up. Conclusion. Intramedullary epidermoid cysts should be considered in the differential diagnosis of neurological decline post-myelomeningocele repair. MRI including diffusion-weighted sequences is essential for diagnosis, and timely surgical intervention leads to favorable outcomes.