Monday, January 2nd

Been getting a little nervous about the surgery.  The neurosurgeon gave me a brochure describing the procedure, but it wasn't very descriptive.   So, off to the World Wide Web to get the low down.  This was one of the best descriptions, while not the exact location, it does convey the general procedure well.  This information is courtesy of the Mayfield Clinic. 

What happens during surgery?

There are 6 main steps during a craniotomy. Depending on the underlying problem being treated and complexity, the procedure can take 3 to 5 hours or longer.

Step 1: prepare the patient 

No food or drink is permitted past midnight the night before surgery. Patients are admitted to the hospital the morning of the craniotomy. With an intravenous (IV) line placed in your arm, general anesthesia is administered while you lie on the operating table. Once asleep, your head is placed in a 3-pin skull fixation device, which attaches to the table and holds your head in position during the procedure (Fig. 2). Insertion of a lumbar drain in your lower back helps remove cerebrospinal fluid (CSF), thus allowing the brain to relax during surgery. A brain-relaxing drug called mannitol may be given.

Figure 2. The patient’s head is placed in a three-pin Mayfield skull clamp. The clamp attaches to the operative table and holds the head absolutely still during delicate brain surgery. The skin incision is usually made behind the hairline (dashed line). 

Step 2: make a skin incision

After the scalp is prepped with an antiseptic, a skin incision is made, usually behind the hairline. The surgeon attempts to ensure a good cosmetic result after surgery. Sometimes a hair sparing technique can be used that requires shaving only a 1/4-inch wide area along the proposed incision. Sometimes the entire incision area may be shaved.

Step 3: perform a craniotomy, open the skull 

The skin and muscles are lifted off the bone and folded back. Next, one or more small burr holes are made in the skull with a drill. Inserting a special saw through the burr holes, the surgeon uses this craniotome to cut the outline of a bone flap (Fig. 3). The cut bone flap is lifted and removed to expose the protective covering of the brain called the dura. The bone flap is safely stored until it is replaced at the end of the procedure.

Figure 3. A craniotomy is cut with a special saw called a craniotome. The bone flap is removed to reveal the protective covering of the brain called the dura. 

Step 4: exposure the brain

After opening the dura with surgical scissors, the surgeon folds it back to expose the brain (Fig. 4). Retractors placed on the brain gently open a corridor to the area needing repair or removal. Neurosurgeons use special magnification glasses, called loupes, or an operating microscope to see the delicate nerves and vessels.

Figure 4. The dura is opened and folded back to expose the brain.

Step 5: correct the problem

Because the brain is tightly enclosed inside the bony skull, tissues cannot be easily moved aside to access and repair problems. Neurosurgeons use a variety of very small tools and instruments to work deep inside the brain. These include long-handled scissors, dissectors and drills, lasers, ultrasonic aspirators (uses a fine jet of water to break up tumors and suction up the pieces), and computer image-guidance systems. 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 make sure it is not further damaged during surgery.

Step 6: close the craniotomy

With the problem removed or repaired, the retractors holding the brain are removed and the dura is closed with sutures. The bone flap is replaced back in its original position and secured to the skull with titanium plates and screws (Fig. 5). The plates and screws remain permanently to support the area; these can sometimes be felt under your skin. In some cases, 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. A turban-like or soft adhesive dressing is placed over the incision.

Figure 5. The bone flap is replaced and secured to the skull with tiny plates and screws.