Anterior skull base
The anterior skull base is formed by the orbit bones and the bones which comprise the nasal sinuses. The anterior skull base can often be reached without making an incision from the outside through the nose using visual aids such as surgical microscopes or endoscopes. Therefore, an incision from the outside is not always required for a tumor on the anterior skull base. For large tumors which cannot be removed via an approach through the nose and which grow into the brain, surgery is performed by a team of specially trained otorhinolaryngologic surgeon and neurosurgeons.