What is a craniotomy?
A craniotomy, or surgical hole in the skull, may be necessary on its own to relieve pressure, but also as a means to access the brain for various other procedures.
Craniotomy is a procedure in which a neurosurgeon surgically removes a section of the skull in order to gain access to the brain. The portion of skull removed is called a “bone flap,” which is often placed back in its original position after the operation is completed. The bone flap is typically fastened into place with low-profile titanium plates and screws. When the surgeon does not replace the bone flap for some reason, it is called a “craniectomy.”
A craniotomy guided by MRI-based navigational software is called a “stereotactic craniotomy.” Stereotactic craniotomy is usually the standard procedure in planned surgeries. With improvement in navigational software accuracy and surgical techniques, surgeons choose to do minimally invasive keyhole craniotomies when possible.
A less invasive method is a “burr hole” craniotomy in which the surgeon drills a hole in the skull. This provides a limited view and may be used for draining cerebrospinal fluid, draining blood from a hemorrhage, and to relieve pressure on the brain (intracranial pressure). The burr hole may also be used as a port for an endoscope, so the surgeon is able to determine a further course of action during the procedure.
When is a craniotomy performed?
A neurosurgeon performs a craniotomy to access the brain for surgery. The surgery maybe involve the following:
- brain tissue,
- blood vessels in the brain,
- meninges (the membranes covering the brain)
- skull bone
A craniotomy maybe required for the following surgeries:
- Clipping of a cerebral aneurysm
- Resection of arteriovenous malformation (AVM)
- Removal of brain abscess
- Resection of brain tumor
Biopsy or resection of abnormal brain tissue
- Draining of hematoma
- Treatment of epilepsy
- Placing implants such as a shunt, brain stimulator or electrodes for seizure monitoring
- Removing pressure on tiny blood vessels for conditions such as trigeminal neuralgia
- Repair of skull fracture
- Relieving elevated intracranial pressure (craniectomy)
How serious is crainotomy surgery?
Craniotomy, like any surgical operation, carries its particular risks. Craniotomy is primarily a means to an end, so the seriousness of complications may depend mostly on the location on the brain and the type of surgery performed. Despite potential complications, a craniotomy may save lives, and individuals with no other pre-existing conditions are likely to recover fully with good care and treatment.
The following are some of the risks with craniotomy that are common to any surgery:
- bleeding
- infections
- blood clots
- reaction to anesthesia
- pneumonia
- unstable blood pressure
- myocardial infarction
Some of the specific complications that can arise post-craniotomy are:
- cerebral bleeding or hematoma at the surgical site
- seizures due to disruption of normal brain tissue
- stroke due to damage to a blood vessel
- cerebrospinal fluid leak
- brain swelling
- infection at the surgical site
- air within the cranium (pneumocephalus) introduced through the craniotomy site, which may cause confusion, lethargy, headache, seizures, and nausea/vomiting
Some individuals, depending on the location, site of surgery, and pre-existing medical conditions prior to surgery might encounter:
In patients with certain medical conditions the risks are higher, and the surgeon might decide on surgery only if the benefits of surgery outweigh the risks. The following factors increase the risks involved in a craniotomy and brain surgery in some patients:
- advanced age
- cardiopulmonary disease
- poor functional health
- systemic collapse due to sepsis or multi-organ failure
Many of the risks associated with a craniotomy have been minimized with pre-procedure blood tests, advanced imaging technologies, improved surgical techniques, postoperative care and medications.