Extra-ventricular application of flexible neuro-endoscopy in intracranial epidermoid cyst open resection: A novel...

Intracranial epidermoid cysts are congenital lesions with a predilection for midline or paramedian spaces including the cerebellopontine cistern, fourth ventricle, or the interhemispheric fissure. The only effective treatment is resection. Conventionally, epidermoid cysts are resected with open transcranial approaches. The advent of neuroendoscopy has allowed for less invasive options and can assist open microneurosurgery in better visualization of the lesion around corners. As rigid neuroendoscopes are limited in accessing tight corners, flexible endoscopy has been proposed to assist neurosurgery, with the additional angles of view and the advantage of tip-steerability. We present a case of flexible endoscopy assistance in epidermoid cyst resection.

A 41-year-old woman presents with a posterior fossa epidermoid cyst, where suboccipital craniotomy and flexible endoscopy-assisted resection allowed for visualization of the remaining cranial portion of the tumor in the 4^th ventricle without excessive brain retraction, guide microsurgical instruments into the cavity, and confirm clearance of clots and debris in the cerebral aqueduct. A 62-year-old man presents with an interhemispheric epidermoid cyst, where bifrontal craniotomy, pure left hemispheric approach, and flexible endoscopy assistance allowed resection of cystic components in difficult areas with an acute angulation.

We illustrate the novel use of flexible endoscopy to assist with the resection of a recurrent posterior fossa epidermoid cyst and an interhemispheric epidermoid cyst.