Wide Awake… During Brain Surgery

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Imagine…you’re lying down in a room full of people attending to your every need. One person asks how you’re feeling. Another jokes with you. Yet another holds your hand. When you start to feel tired, they let you sleep.

This may sound like an ideal experience except that you’re lying on an operating table and the people catering to your every need are nurses, surgical assistants and surgeons.

That was Bruce Attenborough’s experience recently when he underwent brain surgery to remove a malignant tumour… AWAKE.

Bruce was diagnosed with the brain tumour this past April and was referred to Dr. Arlan Mintz, neurosurgeon at Trillium Health Centre. The tumour was located within the right motor area, a region of the brain responsible for controlling Bruce’s motor functions.

In conventional brain surgery, the patient is put under general anaesthesia, making it impossible to tell during the operation whether the brain has received any accidental injury. Even if damage is observed after the surgery, it is already too late and may render the patient incapacitated for life.

Realizing the risk of damage to Bruce’s motor skills if treated with a traditional craniotomy, Dr. Mintz recommended Bruce undergo brain surgery fully conscious. By keeping him awake, surgeons would be able to monitor his facial and motor functions, and thus avoid the crucial areas of the brain that control them.

What was Bruce’s reaction to his surgeon’s recommendation? “I trust Dr. Mintz completely so I did not hesitate about making the decision to go ahead with the awake craniotomy,” says Bruce.

Within two weeks, Bruce was on the operating table.

“The awake craniotomy is more effective than traditional craniotomies, as it allows us to continuously observe the motor control areas of the brain,” says Dr. Mintz. “By keeping the patient awake, we are able to identify and avoid the vital areas of speech, sensation and movement.”

The success of the awake craniotomy is aided by Trillium’s innovative use of advanced computer technology in the operating room. Through an MRI, neurosurgeons perform brain mapping to capture a three-dimensional electronic model of the brain. Reference markers known as fudicials are strategically placed on the patient’s scalp, which act as connecters between the computer imaging and the patient’s brain. When an electronic probe is touched to the surface of the brain, the fudicials pinpoint the exact location of the probe to the imaging system, which generates a corresponding image.

“Image guidance is a crucial step in the surgery, allowing us to accurately identify small tumours beneath critical brain structures,” says Dr. Mintz.

During Bruce’s surgery, general anaesthetics were used to keep him drowsy while a small piece of his skullcap was removed. Maintaining deep sedation is necessary during the initial stages of scalp opening, bone removal and the opening of the dura, as these are the segments during which the patient would experience pain or discomfort. When the brain was accessible, the chemical level of the anaesthetics was dropped and Bruce returned to consciousness, able to think, speak and move as usual. Only head movement was restricted with the use of a restraining device.

Since the brain itself has no pain receptors, the patient does not experience pain while awake. While being operated on, Bruce was able to observe and speak freely to Trillium staff. “I feel great. I couldn’t feel better,” exclaimed Bruce at one point.

With Bruce fully awake, Dr. Mintz performed functional mapping to locate the motor control areas of Bruce’s brain. A cortical stimulator was used to make contact with brain tissue overlying the tumour, while Bruce was asked to count and perform simple movements, such as wiggling his toes or fingers. By monitoring Bruce’s facial and motor functions, surgeons were able to map out and avoid the essential motor control areas of the brain, resulting in less risk of damage to these areas.

“In Bruce’s case the tumour was located beneath the primary motor area and was unidentifiable by looking at the surface of the brain. Image guidance and cortical mapping were essential in avoiding injury to the area,” says Dr. Mintz. Having defined the motor area of Bruce’s brain, Dr. Mintz and his team were able to avoid this vital area and skillfully remove the cherry-size tumour with minimal complications and blood loss.

While previously used only in the treatment of epilepsy, advances in anaesthetics and computer technology have allowed neuro-patients such as Bruce to reap the benefits of the awake craniotomy.

“In conventional craniotomies, the tumour is often not completely removed, due to fear of causing further neurological damage. The awake craniotomy allows us to get closer to critical areas of the brain and monitor vital motor functions, thus maximizing the volume of the tumour which can be removed,” says Dr. Mintz.

The technique is less invasive, as brain mapping allows surgeons to isolate the location of the tumour and thus remove a smaller portion of the skull. Recovery is also improved.

“With fewer complications, less risk of infection, and avoidance of invasive monitoring such as arterial lines and foley catheters, awake craniotomy patients are discharged much sooner,” says Dr. Mintz. “Patients generally are out of hospital in two days as opposed to the five or six days patients with traditional craniotomies require.”

Despite the advantages, only 10-20% of neurosurgeons perform awake craniotomies, as they require greater time, expertise and equipment. “The awake craniotomy is much more labour intensive than traditional craniotomies,” says Dr. Mintz. “The procedure is more difficult, requiring a greater deal of time, expertise and staff resourcing.”

Trillium Health Centre is one of few health centres to offer the beneficial procedure, extending its reach to serve the needs of suitable patients both within and beyond the community.

Bruce was released from Trillium within 48 hours of his surgery. He is now successfully recuperating at home with his loved ones.