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FRAMELESS STEREOTACTIC CRANIOTOMY
With an image guided craniotomy small sticky markers are placed upon the patient's head, usually on the forehead, behind the ears and at the level of the mass. The patient then undergoes a CT scan or MRI with the markers in place. That information is then transferred to the image guidance computer. There a virtual model of the person's head and the person's mass is reconstructed. The patient is then brought into the operating room and put to sleep. The patient's head is placed into a skull clamp to make sure that there is no moving during the actual operation. The computer-generated reproduction of the mass is then outlined on the patient's head. Minimal hair is shaved. An incision is made. A bone flap is removed. The bone flap will be placed back later on, held in place with small metal plates and screws. These plates to not rust and they do not set off the airport detectors. The covering of the brain is opened. Sometimes the covering of the brain has to be removed if the mass has infiltrated the covering. Sometimes the skull cannot be put back because this mass has infiltrated the skull. In that case a plastic plate will be inserted in place of the bone. An image-guided system is then used to develop a pathway to the mass. There is constant real-time navigation of the surgeon's instruments that are used to resect the mass. After resection, the covering of the brain, the skull and the skin are closed. Sometimes a drain is placed underneath the skin to decrease the swelling that is expected afterwards.
SKULL BASE SURGERY
Lesions will often present in extremely difficult locations at the base of the skull. These lesions can be benign or malignant. However, because of there location continued growth will likely lead to high morbidity and mortality. It was once thought that the skull base was inaccessible. However, there have been dramatic improvements in anatomy, microscopy, endoscopy, imaging techniques and surgical techniques. This allows resection and reconstruction of the skull and minimalizes brain retraction and intrusion. As a matter of fact with advanced skull base techniques masses can now be removed or debulked that were once thought to be in remote locations. The skull base approach team is often supplemented with ENT surgeons, opthalmalogical surgeons or plastic surgeons. Prior to any intervention the mass should be discussed with the skull base neurosurgeon.
BENIGN TUMOR RESECTION
Pituitary adenomas are resected with the assistance of the ENT surgeon. The smaller tumors are resected endoscopically. Endoscopic resection is easier on the patient, usually excludes the need for nasal packing and allows the patient to go home in 1-3 days if appropriate. Pituitary surgery is not always required but may be an alternative to failed medical therapy or a necessity to lesions with symptomatic mass effect.
Acoustic neuromas are sometimes resected with the assistance of the ENT surgeon. The type of resection and approach is dependant upon the exact location, size of mass and the amount of functional hearing. It is better to deal with these masses before they compress the brain stem. These masses like some of the other brain tumors may also respond to "focused beam" radiation. This is best discussed with the neurosurgeon and other brain tumor team members.
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