Skull Base Surgery
The term "skull base tumor" refers to a group of tumors that have a tendency to grow along different regions of the bottom part of the skull, mostly on the inside but occasionally also on the outside of the skull. Several tumors that occur throughout the skull base include meningiomas, schwannomas, chordomas, glomus tumors, chondrosarcomas, and metastatic tumors, including malignant head and neck tumors. Skull base tumors are relatively rare.
Since tumors of the skull base sit underneath the brain, it can be difficult during surgery to get to the tumor in order to remove it. Traditional techniques used to approach tumors of the brain itself can be used to approach skull base tumors, but these often require significant force to retract the patient’s brain out of the way. This may lead to unwanted injury to otherwise normal brain tissue.
The basic concept of skull base surgery is to approach the tumor from underneath or from the side by removing specific areas of skull base bone. Thus, the tumor can be exposed with little to no brain retraction. Skull base procedures, for example, may be designed to traverse the bone containing the ear (trans-temporal/trans-petrosal/retrosigmoid approaches), low on the temple beneath the brain (middle fossa approach), around the eye (trans-orbital/orbital-zygomatic/craniofacial approaches), through the nose or paranasal sinuses (trans-sphenoidal/trans-ethmoidal/trans-facial approaches), or from the neck (trans-cervical). Fundamentally, these are minimally-invasive techniques designed to maximize tumor removal while preserving neurological function to the greatest extent possible.
The Skull Base Team
Surgery is generally required with a team of physicians including neurotologists, neurosurgeons, head and neck surgeons, ophthalmologists, internists and others. There are numerous approaches utilized, depending on the size and location of the tumor, as well as the health and neurologic status of the patient. In addition, consideration is made regarding the hearing status in both ears. Lastly the approach is based on the skill and experience of the surgical team. Further treatment can also include radiation therapy and/or stereotactic radiosurgery.