A craniotomy is a surgical procedure through which the surgeon removes a part of the bone from the skull to access the brain. The surgeon then uses specialised tools to remove the bone flap temporarily and treat the medical condition. Once the condition is treated, the surgeon places the bone flap back to cover the exposed brain.
A craniotomy might be performed to treat a brain tumour, a blood clot in the brain, an aneurysm, a traumatic head injury, swelling in the brain tissue, infection or a foreign object. A craniotomy can be small or large depending on the underlying issue. They also vary in complexity. Small craniotomies are known as burr holes; whereas larger craniotomies are known as keyhole surgeries.
A craniotomy is generally performed with the assistance of stereotactic frames, image-guiders such as MRI, ultrasound, CT scan, etc. Moreover, endoscopes can also be used for assistance.
Typically, burr and keyhole craniotomies are performed to:
Place a shunt into Craniotomy
- the brain ventricle to flush out the excess cerebrospinal fluid
- Place a deep brain stimulator
- Collect a sample tissue for biopsy
- Guide an endoscope to treat larger issues such as tumour removal
- Drain a clot in the brain
- Place an intracranial pressure monitor
That said, complicated skull-based craniotomies, include removing the bone supporting the bottom of the brain.
Types of craniotomy
Some of the common types of craniotomies include:
- Extended bifrontal procedure
- Minimally invasive supra-orbital craniotomy
- Keyhole craniotomy
- Orbitozygomatic Craniotomy
- Translabyrinthine Craniotomy
Reasons for craniotomy
A craniotomy can be performed for multiple reasons. Some of the most common purposes of a craniotomy include:
- Identifying, removing or treating tumours of the brain
- Repairing an aneurysm
- Eliminating blood clots or blood from a leaking blood vessel
- Treating skull fractures
- Curing epilepsy
- Draining out the brain abscess
- Removing malformations and brain fistulas
- Reducing the pressure in the brain
- Placing stimulator devices to cure movement issues such as dystonia, Parkinson’s disease and others
However, these are not the only reasons for a craniotomy. A doctor can also suggest a craniotomy for a specific medical case.
Risk of craniotomy
Typically, brain surgery is linked to a specific area in the brain, which will be treated. Thus, the risks and complications are associated with the area that is being treated. Such as, if there is an issue in the part of the brain that controls speech, the complications will be related to speech.
That said, some of the common risks associated with a craniotomy include:
- Blood clots
- Fluctuating blood pressure
- Allergic reaction to anaesthesia
- Swelling in the brain
- Leakage of the cerebrospinal fluid
- Weakness in the muscles
However, the below complications are more specific to a particular issue within the brain. These will apply only to individuals that have the same underlying problem.
- Problem with memory
- Difficulty in speech
- An issue in balancing or coordination
The procedure of a craniotomy
Before the procedure, the doctor will ask the patient to sign the consent form and then will conduct a preoperative neurological exam to assess the condition after the craniotomy. The patient will be asked to not eat or drink anything starting the midnight of the procedure. Women who are pregnant or think they might be pregnant, are required to disclose the same to the doctor.
The patient should also disclose any allergies or ongoing medications, as well as health complications. Smokers would be required to quit smoking and also inform about any bleeding disorders. The patient will be given a sedative before the surgery and the place of treatment will be shaved.
During the craniotomy, an intravenous line (IV) line will be placed in the arm or the hand of the patient. After this, the surgeon will make an incision as per the specific issue to be treated. Some craniotomies will involve making an incision from behind the hairline in front of the ear, etc. For procedures that require an endoscope, the incision made will be small.
The surgeon will then pull the scalp up and clip it to control bleeding and access the brain. Then a medical drill will be used to make the required holes in the skull. Post this, the bone flap will be removed and placed aside. Then the thick covering of the brain is removed to access the target area. The surgeon uses microsurgical and special instruments to treat the issue. Once the treatment is done, the surgeon sutures the layers of the brain and places the bone flap back with plates, sutures or wires.
However, in cases, where the bone has a tumour or an infection, the surgeon may not replace the bone flap. The scalp is then sutured or stapled, and a sterile bandage is placed over the incision.
Typically, a craniotomy requires the patient to stay under observation for 3 to 7 days or more depending on the condition of the patient. After the surgery, the recovery process can take 3 to 4 weeks, during which the patient will be directed to follow precautions and take medications, as suggested by the doctor.
However, if the patient experiences any of the following problems after the surgery, immediate medical attention should be sought:
- Feeling sleepy all the time
- Weakness in the arms and legs
- Problem with speech
- Changes in vision
- Pain around the site of the incision
- Problem in breathing
- Chest pain
- Issues in mental health
- Discoloured phlegm
Overall, a craniotomy is a very effective procedure, but it has its advantages and disadvantages. The suitability of a craniotomy for a patient is determined by the doctor depending on the underlying issue, general health of the patient and the medical history.