Last week Senator Edward Kennedy underwent 'awake neurosurgery' to remove a malignant tumour in his brain. Claire O'Connellinvestigates what's involved
IT SOUNDS like the stuff of nightmares - being aware while a surgeon pokes and cuts at your brain. But 'awake neurosurgery', where the patient is alert and carries out simple, indicative tasks while the surgeon works, can help avoid inadvertent brain damage and loss of function afterwards.
Last week, US senator Edward Kennedy underwent such surgery to remove malignant tumour tissue from the left side of his brain - a strategy which might improve his response to future chemotherapy and radiotherapy.
The three-and-a-half-hour operation at Duke University Medical Centre was judged a success, and the 76-year-old Massachusetts politician reportedly told his wife immediately afterwards: "I feel like a million bucks. I think I'll do that again tomorrow."
It's a positive spin on a difficult time for Kennedy, but just how effective can brain surgery be?
It can be used to treat dangerous bleeds, blood-vessel malformations and aneurysms, and to remove tumours, explains consultant neurosurgeon Prof Jack Phillips, who recently retired from cranial surgery at Beaumont Hospital and still carries out spinal operations at the Bon Secours Hospital.
Some problems with blood vessels in the brain can be addressed by blocking them off with tiny coils inserted via the groin, and other areas like the pituitary can be accessed through the nose, but opening the skull remains the usual mode of access, says Phillips.
When it comes to tumours, their position in the brain is key, he notes. "If you have a benign tumour, it invariably grows on the surface of the brain, and removing that does not intrude excessively into the brain itself. But issues change completely once you are dealing with a malignant brain tumour."
That's because malignant tumours grow rapidly into the substance of the brain, he explains. "It's like a bowl of white paint, and you pour a dab of red paint into it. The red, or tumour, mixes and mingles with the white paint, or brain, and the roots go all over the place."
Just where those roots spread determines how feasible it is to go in and remove it, and surprisingly large tracts of the brain are operable, according to Phillips.
"Only about one-third of the brain on the right is very valuable, where you can't go. And about half the brain on the left is very valuable and you can't go there," he says. "But of the rest, you can take out large chunks and the patient recovers fully."
However, if a malignant tumour spreads into an area of the brain needed for important functions, surgery becomes even trickier, as exemplified by Kennedy.
"His tumour was located in the dominant left brain, which is the brain with which you speak, write and calculate, make sentences with, find words with and understand what people say to you," says Phillips. "So it's not available to be intruded on excessively."
That's why Kennedy underwent surgery while awake, to help minimise damage to the surrounding brain tissue as the tumour was being removed.
Phillips explains the procedure: "You freeze the scalp, so you don't feel any pain when you open it. The skull itself doesn't have nerve fibres so you can take that out, and while the lining of the surface of the brain has nerve fibres, you can freeze that.
"Then, when you get into the brain, it doesn't have sensory nerve fibres - so you can operate without hurting the patient," he says.
"Sometimes they report a dull pain, but it's very low-grade and tolerable, and the patient is kept going by the anaesthetist with very light sedation which is reversible, so the patient can be fully alert."
The surgeon uses computer imaging to help identify the tumour, and then cuts it out while the patient is asked to carry out simple tasks.
"They ask them to wriggle a finger, thumb or toes, read the following sentence, look at this cartoon - the patient keeps talking and the surgeon keeps operating," explains Phillips. "When you are getting deeper into important areas of the brain you need the patient's response to help avoid damage - they literally will start making sentences very sluggishly and they wouldn't be able to grip your hand tightly."
However, the jury is still out on whether removing cancerous tissue from the brain can improve survival times, which tend to be around a year for aggressive tumours, notes Phillips.
"Not everybody agrees that taking out small amounts of tumour really improves survival, but there are some who think that if you reduce the size then radiotherapy and chemotherapy are more efficient," he says. "But when you put it to patients they often want to take the chance."
And, while the specialist setup for awake neurosurgery is available at Beaumont, it has been carried out there only around a dozen times, according to Phillips.
"Ninety per cent of tumours and aneurysms are doable with the patient asleep. Awake neurosurgery is a major burden - many patients couldn't tolerate it, and having the right patient with the right team is a big set-up for any unit, but it's available if needed."
My philosophy? I just went with the flow
Five years ago, Eddie Kenny had little reason to expect anything major was wrong. "During the day there wasn't a hair out of place," he recalls. "But at night, it felt like I was having a nightmare."
His mother convinced him to get checked out in Accident & Emergency, and she took the call when they rang back two days later to say her son had a tumour just over his left ear.
"I asked 'am I in trouble?'" says Kenny, now 43, but he soon found out that he was relatively lucky, because the tumour was accessible.
His philosophy was to take the treatment as it came.
"I just went with the flow," he says of his brain surgery in Beaumont Hospital, and six weeks of radiotherapy at St Luke's Hospital.
When a later follow-up revealed that he had another growth, he went under the knife again. He still has check-ups twice a year, but so far there's no sign of the cancer returning.
For more information on cancer log on to www.cancer.ieor call The Irish Cancer Society helpline 1800-200 700