“keyhole” craniotomy

Retro-sigmoid craniotomy (usually called “keyhole” craniotomy) is a minimally-invasive operational method done to remove brain tumors. This method allows for the removal of head base tumors through a small hole behind the ear, giving access to the cerebellum and brainstem. A neurosurgeon may use this method to reach specific tumors, such as meningiomas and acoustic neuromas (vestibular schwannomas).