Epidermoid cysts and dermoid cysts are congenital benign tumors originating from ectopic ectodermal tissue within or outside the spinal canal. Epidermoid cysts account for 0.5%–1.5% of intracranial tumors and are commonly located in the cerebellopontine angle or suprasellar region. They are composed of stratified squamous epithelium and contain keratin, cellular debris, and cholesterol. Rupture of the cysts can lead to aseptic meningitis.
Dermoid cysts account for approximately 0.3% of intracranial tumors and contain skin appendages such as hair and sebaceous glands, with some also containing mature bone. They are more commonly found in children and are often located along the midline, including regions such as the fontanelle, fourth ventricle, suprasellar area, and spinal canal, where they manifest corresponding clinical symptoms.
Complete resection of the cyst wall can provide a cure. However, in cases where the wall adheres extensively to critical nerves, aggressive removal is not recommended. Recurrence of the tumor may be treated with additional surgery.