A supratentorial craniotomy is a surgery that involves temporarily removing a piece of bone in the skull to allow access to the brain. A person may have this surgery to treat tumors, bleeding, or infections in the brain.

Major and minor complications may occur, such as headaches, seizures, and bleeding. The short-term survival rate appears favorable, but the long-term survival rate depends on the condition a person has.

To prepare, a person must follow their doctor’s instructions on fasting from food and beverages and which medications to take or avoid before the surgery.

Keep reading to learn more about supratentorial craniotomy, including the conditions it treats, complications, survival rates, and what to expect before, during, and after the procedure.

A surgeon washing his hands preparing to perform a supratentorial craniotomy -1.Share on Pinterest
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A craniotomy is surgery involving the temporary removal of part of the skull — called a bone flap — to expose the brain and perform an operation inside the skull. After the surgery, the surgeon replaces the bone flap.

In some craniotomies, a surgeon uses navigation guidance from an MRI or CT scan to locate the condition or area requiring treatment more precisely. Depending on where this is, a surgeon will perform either a supratentorial or infratentorial craniotomy.

Tentorium is a layer of tissue that separates the cerebrum, which is in the front of the skull, from the cerebellum, which is in the back of the skull. A supratentorial craniotomy treats conditions above the tentorium. This involves the cerebrum, a main part of the brain with many functions.

Learn more about craniotomy procedures.

The purpose of supratentorial craniotomy is to allow a surgeon access to the interior of the brain to treat a range of conditions. The most common ones include:

  • tumor
  • arteriovenous malformation, which is a tangle of blood vessels that affects blood flow
  • subdural hematoma, which is a type of bleeding that occurs due to a blood vessel under the skull rupturing
  • aneurysm, which is a bulge or ballooning out of a blood vessel in the brain
  • subdural empyema, which is an infection that occurs between the outermost and middle layers of the brain’s covering
  • intracerebral hematoma, which is a collection of blood within the cerebrum

While the above are the most frequent uses, surgeons may also perform it to treat:

The surgeon or another healthcare professional will advise you on what to do before and after the procedure:

Before the procedure

People can expect:

  • to undergo various lab tests for health assessment
  • to stop taking blood-thinning medications for several days before the surgery
  • take certain prescribed medications the day of surgery.
  • not to eat or drink anything on the morning of the surgery.

On the day of surgery

The following is likely to occur on the day of the surgery:

  • An anesthesiologist administers general anesthesia, which puts a person in an unconscious state so they will feel no pain. In the awake type of craniotomy, an anesthesiologist administers a local anesthetic so the individual will be awake but still feel no pain.
  • The surgeon shaves off hair near the incision site and sterilizes the area.
  • The surgeon makes an incision in the skin, drills holes in the skull, and uses a medical saw to remove a bone flap.
  • The surgeon repairs or cuts out tissue — such as a tumor — and then replaces the bone flap.

According to anecdotal reports, a person goes to an ICU unit immediately after surgery. They can expect a hospital stay of up to a week or longer, but this can vary. During this time, the healthcare team provides medications and monitors vital signs, such as pulse rate and blood pressure.

The average recovery time ranges from 6–12 weeks. It is important to rest during this period. The doctor will tell the person when it is safe to resume daily activities.

Follow-up appointments with a doctor and other members of the healthcare team, such as a physical or speech therapist, are usually necessary.

According to a 2011 investigation and 2020 study, major complications occur in 8.3% of people who undergo a craniotomy, while about 60% of people who undergo a craniotomy will experience complications. These statistics apply to craniotomy in general rather than only supratentorial craniotomy.

The range of possible complications is extensive, but a few include:

Survival rates vary considerably and can depend on the condition the surgery treats. Below is one example.

A 2020 review and meta-analysis looked at survival rates of awake craniotomy to remove part of a supratentorial glioblastoma, a fast-growing brain tumor. The six studies in the review reported no deaths within the first 30 days. Studies reporting data on overall survival were too different for the authors to calculate a pooled mean estimate, but it ranged from 12–30 months.

A supratentorial craniotomy is a surgery that involves the temporary removal of a piece of bone in the skull to allow access to the cerebrum. Surgeons use it to treat conditions that include tumors, arteriovenous malformations, and aneurysms.

The surgery has the potential to cause an extensive range of major and minor complications, a few of which include bleeding, headache, and hematoma.

A person’s doctor will provide preparation instructions concerning fasting and medications. It is essential to follow them carefully.

Survival rates vary with the condition but tend to be favorable.