Craniotomy/Craniectomy
A craniotomy is a procedure in which an opening is made in the skull to perform surgery on or around the brain. It is used for a wide variety of conditions, including brain tumors, trigeminal neuralgia, epilepsy, brain aneurysms and arteriovenous malformations, Chiari malformation, subdural hematomas, and epidermoid cysts, among others.
During a craniotomy, a piece of bone is removed from the skull using a high-speed drill. At the conclusion of surgery, this piece of bone is secured back in place, usually with tiny titanium plates and screws that are not visible through the skin (picture below). In time, the this piece of bone fuses with the surrounding skull. The plates and screws are not removed.
There are several types of standard craniotomy, for example a pterional craniotomy or a retromastoid craniotomy, but craniotomy is often used in a highly customized way depending on the disorder and part of the brain being treated. Some of the procedure pages on this site, for example microvascular decompression and temporal lobectomy, describe in more detail what to expect from particular types of craniotomy.
Most craniotomies are performed with the patient asleep (under general anesthesia), but I use an awake craniotomy with speech mapping when a tumor or lesion is located near one of the speech centers in the brain.
A craniectomy is a variant of a craniotomy in which the piece of skull removed to access the brain is not replaced at the end of the procedure and is instead left outside of the body, usually in a sterile bone freezer. Why not replace the bone? Craniectomies are usually performed for patients with severe brain swelling, usually from a stroke or a traumatic brain injury. Removing a piece of the skull provides the injured brain extra space so that any swelling doesn’t put dangerous pressure on the surrounding healthy brain. The piece of bone can later be replaced in a second procedure called a cranioplasty after the swelling has resolved. Craniectomy is generally an emergency procedure.
