Procedure description

A craniotomy for acoustic neuroma is performed to remove a benign tumor from within the brain.   

The patient will be taken to the operating room and put to sleep under general anesthesia.  The head will be partially shaved, to expose the area of operation, behind the ear where the tumor lies.  The head is then placed in three fixation points (Mayfield head pins).  This provides the ability to keep the head perfectly still during the procedure.  The patient is turned on their side.  The surgeon may register a navigational device which allows the use of "real time" intraoperative navigation.  The area where surgery is to be performed is then "prepped and draped" using an antibiotic solution.  Next, the surgeon will make an incision, and reflect the scalp over the area of the tumor.  An air powered drill is then used to make a hole in the skull, a drill or rongeur (bone biter) is used to remove a portion of bone overlying the area of the tumor.  The dura mater (tough covering of the brain) is then opened.  An operating microscope is generally brought into the field, and the surgeon will approach the tumor within the brain.      Often the edges of the cerebellum (back portion of the brain)  are gently supported using brain retractors.   Generally the surgeon will attempt to remove all of the tumor, or as much as possible.  Any visible bleeding points will be cauterized.  Often, hemostatic promoting material is gently laid over the surfaces of the brain, and closure is begun.  The surgeon will  close the dura, and may or may not elect to place a covering over the skull.  Possible options for skull replacement are the patient's own bone, surgical cement, methylmethacrylate ( a type of hardened plastic), or titanium mesh.   Next the scalp will be closed in layers.

Procedure Risks

Risks for craniotomy for acoustic neuroma can be broken down into two categories, 1) those related to the operative site, and 2) those related to the risks of anesthesia. 

Risks related to the operative site

Surgical Exposure:  The patient is placed in a position so as to allow the surgeon good access to the tumor.     There is risk of non healing of the scalp  post operatively.  Although very uncommon, there can be injury to or tearing of the scalp from the pins on the Mayfield clamp.  There is the potential for spinal fluid leak postoperatively, which may require additional surgery to repair.

Brain injury:  The surgery involves opening the back of the skull behind the ear, and gently retracting the cerebellum ( back of the brain), to expose the tumor.  There can be damage to the cerebellum, brainstem, and cranial nerves (nerves leaving the brainstem and providing functions such as hearing, facial movement, and facial sensation).  These tumors generally arise from the nerves supplying balance (vestibular nerves), and the tumors are usually adherent to the nerve supplying hearing and facial movement.  Depending upon the size of the tumor, hearing may be lost (if not already lost due to the tumor prior to surgery) due to surgery, and facial function may be completely lost on the side of the face where the tumor is located.  Sometimes the facial function will return if the nerve has only been bruised but is anatomically intact.   If there is brain injury, this could result in weakness, seizures, stroke, paralysis, coma or death.  There may be residual fluid or blood, requiring additional surgery in the future.  There is a possibility of tumor remaining after surgery, or of recurrence of tumor in the future.

General Risks

These include such general difficulties, such as bleeding, infection, stroke, paralysis, coma and death.  Incisions on the scalp generally heal well, but could become  tender, numb,  or may heal in an unpleasant manner.  If there is hearing loss preoperatively, generally this will not improve with surgery, and may in fact worsen, resulting in deafness.  Balance problems may not improve, and may worsen.  The tumor  may recur, requiring additional surgery or radiation in the future.  In addition, although every attempt is made to protect all areas of the body from pressure on nerves, skin and bones, injuries to these areas can occur, particularly with prolonged cases.

Risks of Anesthesia: Blood clots in the legs, heart attacks, reaction to the anesthetic, reaction to blood transfusion, if it given

 

Post-operative care:

There is surprisingly relatively little pain associated with craniotomies.  Your surgeon will prescribe pain medications for any pain associated with the incision. 

1. Immediately upon discharge, contact our office and set up an appointment for staple removal if one has not already been set up.
2. Take it easy until seen by the physician.  This does not mean bed rest, but athletic activities during this period are definitely not recommended.  Please give your incision a chance to heal.  Avoid any type of activity which might risk a blow to the head.
3. You may resume activity as your body permits, but avoid extremes.  For example, walking is fine, but avoid any strenuous running.  USE GOOD JUDGMENT  AND COMMON SENSE.  If you have a question, ask your doctor.
4. No driving until cleared with your surgeon.  A driving test may be required, at the discretion of your surgeon.  Even though you may feel fine, your peripheral vision and reflexes may have been affected, and we want you to be safe on the road for yourself as well as for others.
5. You may shower after you go home unless otherwise instructed.  Cover the incision with plastic wrap before the shower and remove it afterward.  Change dressing immediately.    You may shower without covering the incision one week after the staples are out.  Follow instructions concerning care of tapestrips, stitches or staples.  Your surgeon or his nurse clinician will explain the techniques used in the closure of your incision.
6. Sexual activities are permitted.
7. If you notice swelling, redness or opening of the incision, or if there is any clear fluid draining from it, please contact your surgeon immediately!  If you develop a fever, stiff neck or chills, contact the office immediately.  Take your temperature at 4:00 PM daily until the clips are removed.  Call if greater than 101 degrees Fahrenheit.
8. If you have a seizure, notify our office or come to the emergency room.
9. If you develop any new weakness, notify our office.
10. If you have any paralysis or weakness, post-operative care will need to be tailored to this.  If a brace for an arm of a leg has been prescribed, use it as recommended by your surgeon.
11. If you have any questions, call our office, and for after hours emergencies, call the medical society.
12. Take your medications prescribed on discharge, as directed.
13. Do not take any medications which will "thin the blood" such as coumadin or aspirin, or other non-steroidal antiinflammatory medications, unless otherwise advised by your physicians.
14. Make sure to follow up with any other physicians involved in your care.  These may include your family physician, neurologist, radiation oncologist and oncologist.