The Stroke and Neurovascular Center of Central California

Operative Procedures

What is a Craniotomy?

Open brain surgery usually involves a procedure called a craniotomy. A craniotomy is a major surgical procedure performed under general anesthesia by a Neurosurgeon. “Crani” means skull and “otomy” means cutting into. Part of the skull, called a bone flap, is removed in order to gain access to the brain. This bone flap is usually replaced after the procedure with tiny plates and screws. If the bone is not replaced the procedure is called a Craniectomy. There are many different types of craniotomies which are named according to the area of the skull that is to be removed and the size and complexity. Surgeons often use sophisticated computers to plan these craniotomies and locate the lesion.

Who are candidates for Open Brain Surgery?

A craniotomy may be performed:

  • To repair a fracture
  • To remove or treat:
    • Brain Tumors
    • Cavernous Malformations
    • Aneurysms
    • AVM’s
  • To remove a blood clot (hematoma)
  • To treat an area of infection
  • To drain a brain abscess
  • To relieve pressure inside the skull
  • To remove a foreign object (bullet)
  • For Cerebral Bypass Surgery (see Moyamoya)

Small dime shaped craniotomies are known as burr holes or keyhole craniotomies. We use these minimally invasive procedures to:

  • Insert a shunt into the ventricles to drain cerebrospinal fluid due to hydrocephalus
  • Insert an intracranial pressure (ICP) monitor
  • Remove a small sample of abnormal tissue (needle biopsy)
  • Drain a blood clot (stereotactic hematoma aspiration)
Risks Associated with an Open Surgery

Neurosurgical procedures may result in bleeding, infection, blood clots, reactions to anesthesia, or unintended injury to normal nerve tissues. Specific complications related to an open surgery may include:

  • Stroke
  • Seizure
  • Retention of fluid causing swelling (edema), which may require a second craniotomy
  • Nerve damage, which may cause muscle paralysis or weakness
  • CSF leak, which may require repair
  • Loss of mental functions
  • Permanent brain damage with associated disabilities
Preparing for Surgery

This document will help to prepare you for an operative procedure. It will be performed in the Operating Room at Santa Barbara Cottage Hospital by Dr. Zauner. You will be scheduled for a pre-op appointment the day prior to your surgery. Your pre-op appointment will be in the hospital. You will go into the front entrance (Pueblo and Bath) of the hospital for this appointment and you will check in at the same place the morning of your craniotomy. Prior to the procedure you will go over the risks and benefits of surgery and will be asked to sign a consent form. This is also your opportunity to have any questions answered about the surgery.

You will undergo several tests at your pre-op appointment the day before your surgery, including blood test, electrocardiogram, and chest X-ray. At this time you will also sign the consent forms and go over your medical history with the pre-op nurse. Be sure to discuss allergies, medications you are taking, anesthesia reactions, and any previous surgeries you have had. For the majority of cases you will need to discontinue all non-steroidal anti-inflammatory medicines (Ibuprofen, Motrin, Naproxin, Advil, Daypro, etc.) and blood thinners (Coumadin, heparin, aspirin, etc.) one week before surgery. These medications have been correlated with an increase in blood clot formation after surgery. It is also a good idea to stop smoking, chewing tobacco and drinking alcohol at least one week before surgery and two weeks following surgery, as these activities can cause bleeding problems, delay wound healing and cause breathing problems during surgery.

You will be told to stop eating or drinking after midnight the night before the operation. Be sure to ask your doctor which medications you should still take on the day of the surgery. You will bring these with you to the hospital on the morning of your surgery and take them there, with a SMALL sip of water. Patients who do not live here in town are generally advised to stay in a nearby hotel the night before the surgery. This will allow you to drive to Santa Barbara for your pre-op appointment and limit the amount of unnecessary driving the evening before and morning of your procedure. A few local hotels within a mile of Santa Barbara Cottage Hospital include the Lemon Tree Inn, or the Best Western Encina Lodge. Before your surgery it is also important to plan for your care and recovery after the operation. Make sure you have someone to drive you home once you are ready to be discharged, and also someone to help you with your day-to-day duties while you are recovering.

If you don’t have any recent scans, the doctor will order these prior to surgery. Patients who are having a tumor or lesion removed will need to have an MRI with DTI and Fibertracking the day before surgery. This scan is used with Brain Lab Navigation technology to plan and perform open surgery with greater precision. Image-guided surgery allows the doctor to continuously track surgical instruments in relation to the patient’s anatomy, avoiding critical brain structures. The additional visual guidance gives the surgeon the ability to check their progress before concluding surgery which leads to a more successful brain tumor resection.

During Surgery

An intravenous (IV) line is placed in the patients arm and general anesthesia is administered while the patient lies on the operating table. After a general anesthetic has been given, the patient is positioned according to the area of the brain that must be reached. The patient’s head is placed in a three-pin Mayfield skull clamp, which attaches to the operative table and holds the head in position during the procedure.

Mannitol is given in an attempt to control brain swelling and relax the brain. The operation is usually performed with the patient lying on his or her back. The hair over the incision area is clipped and shaved. The scalp is then prepped with antiseptic and a skin incision is made (usually behind the hairline). The skin and muscles are lifted off the bone and folded back to expose the skull.

Next, one or more small burr holes are made in the skull with a power drill. A surgical saw, called a craniotome, is used to connect the holes and create a “window” in the skull through which surgery will take place, without cutting the dura mater (protective covering of the brain). The removed bone flap is kept sterile for replacement at the end of the operation. For a tumor resection, once the dura is exposed, the brain lab probe is used to confirm the location and depth of the underlying tumor, helping the surgeon plan his approach.

The dura is cut with surgical scissors and folded back to expose the brain. Retractors are placed on the brain to create a larger opening in the area needing repair or removal. Throughout this procedure the neurosurgeon uses an operating microscope and a variety of small tools and instruments in order to maneuver through the delicate nerves and vessels deep inside the brain. In some cases, evoked potential monitoring is used to stimulate specific cranial nerves while the response is monitored in the brain. This is done to preserve function of the nerve and ensure the nerve is not damaged during surgery.

Once the problem is removed or repaired the retractors are removed and the dura is closed with sutures. The bone flap is replaced in its original position and secured to the skull using titanium plates and screws, which are MRI compatible. They will remain permanently to support the area. Occasionally a drain may be placed under the skin for a couple of days to remove blood or fluid from the surgical area. The muscles and skin are sutured back together and a soft turban-like dressing is placed over the incision. For more specific information on what is done during each type of operative procedure (aneurysm clip, tumor removal, AVM resection, Bypass procedure, etc.), please see documents pertaining to that particular disease or condition.

After Surgery

Following surgery, the patient is taken to the Neuro-critical Care Unit for close observation. Vital signs are monitored as the patient wakes up from anesthesia and the breathing tube usually remains in place until they have fully recovered from anesthesia. At this point breathing exercises are started to clear the lungs. The patient’s pupil reactions are tested, mental status is assessed, and movement of the limbs (arms/legs) is evaluated. Intracranial pressure is constantly monitored. It is very common for patients to experience nausea and headache after surgery. Depending on the type of brain surgery, patients are given medications to control pain, swelling, and seizures. Special leg stockings are used to prevent blood clot formation after surgery. The bandages on the skull are removed and replaced regularly. Patients will be given intravenous fluids for the first few days. If required (depending on the area of brain involved), occupational therapists and physical therapist assess the patient’s status postoperatively and help the patient improve strength, daily living skills and capabilities, and speech. Patients are able to get out of bed and increase their activity level once their condition stabilizes, and at this point they may be moved to a regular room in the hospital. If complications occur, they will remain in the ICU for an extended period of time. The length of hospital stay varies immensely depending on the surgery and development of any complications. However, most patients are hospitalized for 3-14 days after surgery.

Discharge Instructions

What to Expect

You will be discharged from the hospital when your recovery is ready to be handled at home or at a rehab center. The sutures closing the scalp are removed by the surgeon or nurse practitioner 7-10 days after surgery in Dr. Zauner’s office. Patients should keep the scalp dry until the sutures are removed. The outcomes of brain surgery are highly dependent on the circumstances of your condition. Follow-up appointments or procedures are also highly dependent on the circumstances of your condition. Please see documents pertaining to your particular condition for further information on this. Full recovery may take up to two months, since it is common for patients to feel fatigued for up to eight weeks after surgery. It is also normal for patients to undergo emotional changes after surgery. Support from family and friends during this time will be a very important factor in helping you maintain a positive attitude. Once you are recovering in your home, it is important to monitor changes in your speech and mental ability. Any of these changes should be discussed with your doctor.


After surgery, headache pain is managed with narcotic medication. Because this medication is addictive, they are used for a limited period of time. Their regular use may also cause constipation so it is very important to drink lots of water and eat high fiber foods or even laxatives while taking them. Thereafter, pain is managed with acetaminophen (Tylenol) and Non-steroidal anti-inflammatory drugs (Aspirin, Ibuprofen, Advil, Motrin, Naproxen sodium, Aleve). Medication may be prescribed temporarily to prevent seizures. Common Medications include Dilantin (phenytoin) and Keppra. Some patients develop side effects (drowsiness, balance problems, rashes) caused by these anticonvulsants. If you are on this medication and feel any of these symptoms, call your doctor. The drug levels may need to be altered to manage these side effects.


  • Do not drive after surgery until Dr. Zauner has given you the okay.
  • Avoid sitting for long periods of time
  • Do not lift anything heavier than 5 pounds, including children
  • Working around the house is not permitted until after the first follow-up office visit, if Dr. Zauner approves. This includes gardening, mowing the lawn, vacuuming, ironing, loading/unloading the dishwasher, washer, or dryer.
  • Do not drink alcoholic beverages.


  • You can gradually return to your normal activities. Remember, fatigue is common and it will take some time to feel back to normal.
  • Walking is encouraged, but be sure to start off slow and gradually increase the distance. It is important not to overdo it.
  • Do not participate in other forms of exercise until this has been approved by Dr. Zauner.
  • Find out from Dr. Zauner when you can expect to return to work.

When to Contact your Doctor

If you experience any of the following:

  • A temperature over 101º F
  • An incision showing signs of infection, such as redness, swelling, pain, or drainage.
  • If you are taking an anticonvulsant and notice any side effects
  • Decreased alertness, increased drowsiness, weakness or arms or legs, increased headaches, vomiting, or severe neck pain that prevents you from lowering your chin toward your chest.