What is a craniotomy?
A craniotomy is the surgical removal of part of the bone from the skull to expose the brain. Specialized tools are used to remove the section of bone called the bone flap. The bone flap is temporarily removed, then replaced after the brain surgery has been performed.
Some craniotomy procedures may utilize the guidance of computers and imaging (called intraoperative monitoring) to reach the precise location within the brain that is to be treated. This technique requires the use of a frame placed onto the skull or a frameless system using superficially placed markers on the scalp. When either of these imaging procedures is used along with the craniotomy procedure, it is called stereotactic craniotomy.
Scans made of the brain, in conjunction with these computers and localizing frames, provide a three-dimensional image, for example, of a tumor within the brain. It is useful in making the distinction between tumor tissue and healthy tissue and reaching the precise location of the abnormal tissue.
Other uses include stereotactic biopsy of the brain (a needle is guided into an abnormal area so that a piece of tissue may be removed for examination under a microscope), stereotactic aspiration (removal of fluid from abscesses, hematomas, or cysts), and stereotactic radiosurgery.
Types of craniotomies:
“Eyebrow” craniotomy (supra-orbital craniotomy)
“Keyhole” craniotomy (retro-sigmoid craniotomy)
An endoscopic craniotomy is another type of craniotomy that involves the insertion of a lighted scope with a camera into the brain through a small incision in the skull.
Craniectomy is a similar procedure that involves the permanent removal of a portion of the skull. This is done if swelling is likely after brain surgery or if the skull bone flap cannot be replaced for other reasons.
Other related procedures that may be used to diagnose brain disorders include cerebral arteriogram, computed tomography (CT) scan of the brain, electroencephalogram (EEG), magnetic resonance imaging (MRI) of the brain, positron emission tomography (PET) scan, and x-rays of the skull.
Brain Tumor Surgery
Surgery is the first and most common treatment for most patients with brain tumors at the Johns Hopkins Comprehensive Brain Tumor Center. It is highly successful for most benign tumors. Surgery is usually the best treatment for tumors that neurosurgeons can reach without severely damaging normal brain tissue near the tumor.
Neurosurgeons can surgically remove some tumors completely (called resection or complete removal). If the tumor is near sensitive areas of the brain, neurosurgeons will only be able to remove part of it (called partial removal). Even partial removal can relieve symptoms and facilitate or increase the effectiveness of other treatments.
A biopsy — a surgical procedure to remove a small sample of a brain tumor for examination under a microscope — is usually performed during surgery to remove the tumor. This enables doctors to confirm the diagnosis and recommend the most appropriate treatment. If the patient is not a surgical candidate, a separate biopsy may be done.
The role of surgery in treating brain tumors
Surgery can provide:
- The complete removal of some brain tumors
- A sample to enable doctors to diagnosis the tumor and recommend the most appropriate treatment
- Better quality of life:
- Reduced symptoms and improved ability to function (e.g., to think, speak or see better)
- Less pressure within the skull from the tumor
- A longer life