The pituitary gland is the master gland of the body and produces critical hormones, so tumors or abnormalities can be devastating. All or part of the anterior (front) pituitary may need to be removed. The transsphenoidal approach is currently the most commonly used to remove pituitary tumors. The hollow sphenoid sinus is located behind your nose and right in front of the pituitary gland, which lies in the center of the brain at its base.
The surgeon cuts along the back of the septum (middle part) of the nose into the sphenoid sinus and then drills through the back bony wall of the sinus to access the pituitary. The surgeon usually inserts an endoscope (a small, flexible tube with a video camera at the end) and micro-instruments through this opening to cut off pieces of the pituitary and pull them out through the nose. This approach is best for small tumors.
If a pituitary tumor is large or has spread to adjacent parts of your brain, a craniotomy (surgical opening of the skull) may be necessary for better access. However, this increases the risk of complications. The approach the surgeon uses depends on the location and spread of the tumor. The surgeon may use a subfrontal approach and remove bone in the forehead area above the eyebrows and lift and separate the front part of the brain and go under it to reach the pituitary gland.
In some cases, a transcavernous (through the cavernous sinus) frontotemporal approach on one side of the forehead is used with instruments going through the sinus and under the brain. Another approach used for large tumors is through the back of the mouth and nose (Le Fort maxillotomy), but this requires detaching the maxilla (upper jaw) and then reattaching it after surgery. This approach provides a larger access to the base of the skull where the pituitary is located.
Conventional radiation is sometimes used to treat inoperable pituitary tumors, but this radiation can damage adjacent tissue, including the optic (vision) nerves, and affect hormone production. Radiosurgery (CyberKnife, GammaKnife) uses computer-controlled focused beams of radiation to target precise areas and destroy tissue, avoiding injury to adjacent structures. This is essentially surgery without an incision.
Radiosurgery is appropriate for a small tumor or for residual tumor if it could not all be removed during surgery. Over time, the tumor shrinks, becoming replaced by scar tissue. GammaKnife requires a frame about the patient's head to keep the head immobile during the procedures, but CyberKnife does not require a frame but uses an image-guidance system to stay on target.