[Spinal epidermoid cyst: Iatrogenic neuraxial anesthesia?]

Background: Dermoid and epidermoid tumors are rare lesions that affect the skull and spinal canal, with an incidence of ≈ 0.9% of cases. They are benign lesions originating from ectodermal tissue during embryonic development. They may be congenital or acquired, and the latter are usually secondary to iatrogenic causes (such as lumbar puncture, neuraxial anesthesia or surgical procedures) or to penetrating trauma. Case Report: A 40-year-old woman with a history of 2 lumbar punctures for neuraxial anesthesia. 5 years after the last procedure, she started with low-intensity pain in the upper right thigh. The pain progressively increased in intensity and extended to the anterior aspect of the thigh. On physical examination, a limping gait secondary to intense pain was observed. It was not possible to evaluate muscle strength due to the onset of pain when the patient performed movements against resistance. No sensory deficit or alterations in deep tendon reflexes were found. Sphincter control was normal. Spinal magnetic resonance imaging revealed a rounded intradural, extramedullary lesion at the T11-T12 level. The lesion was surgically removed without complications, resulting in complete resolution of symptoms. Histopathological examination confirmed epidermoid cyst (cholesteatoma). Conclusions: It is demonstrated the development of epidermoid cysts associated with neuraxial anesthetic blocks, typically occurring near or at the puncture site. In this case, it could not be demonstrated anesthetic block was the cause of the lesion.