Brain Tumor: Surgery

What is it and why is it used? Surgery is the primary treatment for accessible brain tumors (tumors that can be approached without causing severe damage). With this form of treatment, a neurosurgeon removes as much of the tumor as possible.

 The purposes of surgery are to:    

1. cure, whenever possible
2. remove as much tumor as possible. Even partial removal of a tumor can relieve symptoms, improve quality of life, and decrease the amount of tumor that must be treated by other methods.
3. establish an exact diagnosis Tumor cells are examined under a microscope by a pathologist.
4. provide access for other treatments. Chemotherapy or radiation implants or genetic materials can be inserted into the tumor bed (the site of the removed tumor). Hyperthermia (heat) treatments can be delivered. Preparation for BNCT (boron neutron capture therapy) can be provided.

What determines a patients suitability for surgery?

• The location of your tumor: If the tumor is considered to be accessible, it can probably be removed without causing severe neurological damage. Tumors deep in the brain, surrounded by critical structures, or in areas that control language or movement, might be inaccessible.
• The tumor’s characteristics: Does it have a distinct border or is it spreading?
• Your general health: Can you endure the strain of surgery and anesthesiology? Are your heart, lungs, kidneys and liver functioning well?
• Your neurological status: Do you have signs of increased intracranial pressure?
• If a second surgery is being considered, how long has it been since the first operation?

Before the surgery the location of your tumor in relation to other structures and blood vessels must be determined as precisely as possible. To achieve this, your doctor will ask you to undergo a variety of tests, which might include CT, MRI or PET scans, and possibly angiography. Using this information, the surgeon can rehearse the operation and plan the safest methods. This is especially true when the Image Guided Stereotactic System is to be used.

Biopsy is a surgical procedure to remove a small piece of tumor in order to make a diagnosis. This is usually done with the stereotactic guidance system, but at tmes it may be performed in the CT scan suite.

Craniotomy is an open formal cranial procedure that is designed to remove as much of the tumor as possible, with the least trauma to the patient. A craniotomy takes planning, using as much information as can be garnered from the studies ordered beforehand. Link to Craniotomy page   

Shunt;  Some patients with brain tumors develop increased intracranial pressure (IICP). To relieve the pressure, a shunt procedure to drain excess or blocked fluid might be required.    A shunt is a narrow piece of flexible tubing (called a catheter) which is inserted into a ventricle in the brain. The other end of the tubing is threaded under the scalp toward the neck, then, still under the skin, threaded to another body cavity where the fluid is drained and absorbed. Link to Hydrocephalus page

Implantation of monitoring devices may be necessary in some patients. These devices are inserted through small opening and are attached to external equipment for continuous monitoring of intracranial pressure, cerebral blood flow, brain temperature, and others.

Ventriculostomy is placement of piece of shunt tubing into the cavity in the brain so that spinal fluid can be drained when needed, and the pressure in the head can be continuously measured.

Surgical techniques and tools have changed a great deal in neurosurgery. The most common tools are the surgical laser, ultrasonic aspirator, operating microscope, and the computerized image guidance system. Other tools include intraoperative monitoring devices and stereotactic apparatus. The choice of tools depends on the type of tumor and its location, and the surgeon’s preference.  At SWMC we have state of the art equipment in all areas.

Intra-operative Ultrasound Imaging This technique uses ultrasonic waves during surgery to determine the depth of the tumor and its diameter. It works by sending ultrasound pulses into the brain which then reflect back to the device. The amount of time it takes for the "echoes" to return is measured by a computer and displayed as a TV image. This is generally used in conjunction with the Brain Lab image guidance system.

Lasers   The use of a laser during surgery is relatively routine. This surgical tool aims laser beams at a target and destroys it with heat. Because the light beams cannot penetrate bone, the laser can be used only during surgery. Lasers are used in addition to, or in place of, a scalpel. Lasers are capable of immense heat and power when focused at close range. Lasers destroy tumor cells by vaporizing them. They are frequently used with stereotactic localization to direct their beams.    The laser’s chief uses are with tumors invading the skull base or deep within the brain, with hard tumors which cannot be removed by suction, or with tumors which cannot withstand pulling-tumors that break apart easily.

	Microsurgery -  Microsurgery is the use of a high-powered microscope during surgery. Microsurgery is widely used for all aspects of neurosurgery.
	Image Guided Surgery - You might compare image guided surgery to a GPS system for the surgeon. This technology superimposes the position of the instruments as they are used in surgery onto images of the anatomy displayed on a computer monitor. Using the computer data from the MRI or CT scanner, the system constructs 3D images of the anatomy of each patient, from which it then superimposes the exact instrument used in surgery. The image guided surgery (IGS) camera works a lot like the satellite that detects signals from cars, boats, and other vehicles equipped with special tracking devices. As the surgeon moves an instrument in the body, infrared cameras, like the GPS satellite, calculates its position, and then transfers that data to a computer in the operating room. The computer then shows the direction the instrument is moving, it’s location relative to the target and the vital structures around it. This state of the art tool is used to orient the surgeon as to the exact location of a target as compared to a specific point on the exterior of the brain.

Transsphenoidal Surgery  This type of surgical approach is often used for pituitary tumors and craniopharyngiomas. Transsphenoidal means through the sphenoid bone- the skull bone under the eyes and over the nose. Prior to surgery, the patient undergoes a complete endocrine evaluation. Hormonal disturbances can affect both surgery and recuperation and must be corrected before the operation and monitored afterwards. Incisions under the top lip and through the nasal passage provide access to the pituitary area where the tumors are located.  

Ultrasonic Aspiration  This tool is used to break tumors apart and then aspirate (suction out) the pieces. Ultrasonic waves cause vibration which fragments the tumor. It causes less disturbance to adjacent tissue than other types of suction devices because it causes less heat and "pull" on normal tissue. This is particularly helpful with tumors that would be difficult to remove with cautery and suction because of their firmness and location. As with the laser, the use of ultrasound has permitted the removal of tumors which would otherwise have been inoperable.