Henry Marsh writes: I often have to cut into the brain and it is something I hate doing. With a pair of short-wave diathermy forceps I coagulate a few millimetres of the brain’s surface, turning the living, glittering pia arachnoid – the transparent membrane that covers the brain – along with its minute and elegant blood vessels, into an ugly scab. With a pair of microscopic scissors I then cut the blood vessels and dig downwards with a fine sucker. I look down the operating microscope, feeling my way through the soft white substance of the brain, trying to find the tumour. The idea that I am cutting and pushing through thought itself, that memories, dreams and reflections should have the consistency of soft white jelly, is simply too strange to understand and all I can see in front of me is matter. Nevertheless, I know that if I stray into the wrong area, into what neurosurgeons call eloquent brain, I will be faced with a damaged and disabled patient afterwards. The brain does not come with helpful labels saying ‘Cut here’ or ‘Don’t cut there’. Eloquent brain looks no different from any other area of the brain, so when I go round to the Recovery Ward after the operation to see what I have achieved, I am always anxious.
There are various ways in which the risk of doing damage can be reduced. There is a form of GPS for brain surgery called Computer Navigation where, instead of satellites orbiting the Earth, there are infrared cameras around the patient’s head which show the surgeon on a computer screen where his instruments are on the patient’s brain scan. You can operate with the patient awake The idea that . . . memories, dreams and reflections should have the consistency of soft white jelly, is simply too strange to understand under local anaesthetic: the eloquent areas of the brain can then be identified by stimulating the brain with an electrode and by giving the patient simple tasks to perform so that one can see if one is causing any damage as the operation proceeds. And then there is skill and experience and knowing when to stop. Quite often one must decide that it is better not to start in the first place and declare the tumour inoperable. Despite these methods, however, much still depends on luck, both good and bad. As I become more and more experienced, it seems that luck becomes ever more important.
I had a patient who had a tumour of the pineal gland. The dualist philosopher Descartes, who argued that mind and brain are entirely separate entities, placed the human soul in the pineal gland. It was here, he said, that the material brain in some magical and mysterious way communicated with the mind and with the immaterial soul. I wonder what he would have said if he could have seen my patients looking at their own brains on a video monitor, as some of them do when I operate under local anaesthetic.
Pineal tumours are very rare. They can be benign and they can be malignant. The benign ones do not necessarily need treatment. The malignant ones are treated with radiotherapy and chemotherapy but can prove fatal nevertheless. In the past they were considered to be inoperable but with modern microscopic neurosurgery this is no longer the case: it is usually now considered necessary to operate at least to obtain a biopsy – to remove a small part of the tumour for a precise diagnosis of the type so that you can then decide how best to treat it. The biopsy result will tell you whether to remove all of the tumour or whether to leave most of it in place, and whether the patient needs radiotherapy and chemotherapy. Since the pineal is buried deep in the middle of the brain the operation is, as surgeons say, a technical challenge; neurosurgeons look with awe and excitement at brain scans showing pineal tumours, like mountaineers looking up at a great peak that they hope to climb. To make matters worse, this particular patient – a very fit and athletic man in his thirties who had developed severe headaches as the tumour obstructed the normal circulation of cerebro-spinal fluid around his brain – had found it very hard to accept that he had a life-threatening illness and that his life was now out of his control. I had had many anxious conversations and phone calls with him over the days before the operation. I explained that the risks of the surgery, which included death or a major stroke, were ultimately less than the risks of not operating. He laboriously typed everything I said into his smartphone, as if taking down the long words – obstructive hydrocephalus, endoscopic ventriculostomy, pineocytoma, pineoblastoma – would somehow put him back in charge and save him. Anxiety is contagious – it is one of the reasons surgeons must distance themselves from their patients – and his anxiety, combined with my feeling of profound failure about an operation I had carried out a week earlier meant that I faced the prospect of operating upon him with dread. I had seen him the night before the operation. When I see my patients the night before surgery I try not to dwell on the risks of the operation ahead, which I will already have discussed in detail at an earlier meeting. His wife was sitting beside him, looking quite sick with fear. [Continue reading…]