Thursday, July 23, 2009

The brain's the game

kw: book reviews, nonfiction, medicine, surgery, neurosurgeons

"It doesn't take a brain surgeon . . . " "Haw, haw, haw!" You know how it goes. Katrina Firlik really is a brain surgeon, and in her new book she points out that, like other surgical specialists, a neurosurgeon needs to be a really, really skilled mechanic. I fully agree. When I had my cancer surgery in 2000, I cared most that my surgeon have great mechanical abilities. Whether he'd have much personality—I'd call it "adequate"—didn't matter much. I wanted a mechanically brilliant, obsessive-compulsive, highly focused pair of hands and eyes to do the rearranging of my insides. Thank God, that's exactly what I got.

Dr. Firlik has all this, plus a great writing style. I devoured her book at a speed I usually reserve for rollicking space opera. In Another Day in the Frontal Lobes: A Brain Surgeon Exposes Life on the Inside she takes us into her world, and a fascinating world it is.

Pre-warning: I have only one photo in this post, and it is likely to disturb you. Brace yourself.

After a couple chapters getting us oriented, the text roughly parallels the seven-year residency a neurosurgeon experiences (life starts at thirty-two!). The Mechanic analogy is fully explored in the first chapter, then we find what a neurosurgeon is and is not. For example, "brain surgeon" is an inadequate term: A neurosurgeon is equally responsible for the spinal cord and the major nerves that emerge from it. Orthopedic surgeons and neurosurgeons can both treat back pain, and if your back hurts, it is a good idea to talk to one of each before choosing a treatment option.

About 15 years ago a friend of mine had a tumor removed from the neck-shoulder region, and the surgeon cut a major nerve. He referred himself directly to Mayo Clinic, where a neurosurgeon located the two ends of the nerve, which is the size of a strand of spaghetti but somewhat softer, and reattached them. My friend regained the use of his arm. Somehow the brain and body figured out the scrambled joint, because there's no way to get every neuron re-connected to its own severed end. But without the neurosurgeon's work, he'd have had a "dead" arm the rest of his life.

But it is the brain that most fascinates most of us, and the author knows it, and focuses most of the book on brain work. She has another apt analogy for us: Surgery as "controlled trauma". The control part is key; it is what allows us to recover as quickly as we typically do from being re-plumbed or re-wired. She tells of a friend who wanted to see brain surgery in action. After seeing a mallet and chisel being used right between a patient's eyes, he remarked, "I could go out and get hit by a bus, and I'd be having a better day than that guy." He was wrong. Two days later, that patient was sitting up asking what was for breakfast. A bus victim would likely be incommunicado for a few days longer…if he lived.

It is a wonder that the nervous system can suffer such great insults and recover so well. Some strokes, injuries or surgeries result in the loss of quite a lot of the brain, but in time the patient recovers many skills that were initially lost. There is a limit, however, which is illustrated by the various results a bullet to the head may have.

A bullet that passes through the upper skull and brain may leave a person significantly impaired, for a while, but because of "brain plasticity" recovery can be surprisingly complete. A bullet passage lower down, that cuts off the deeper structures, is more likely to be fatal, or to produce a "vegetative state". In fact, if a CT scan or MRI shows that the brain is so profoundly damaged that survival is impossible, the surgeon will simply sew shut the bullet wounds and do nothing more. The brain is going to kill itself, and leaving the woulds open will make the process take longer and leave a bigger mess: half the brain will gradually exit the wounds if they are left open. The brain stem, that keeps an otherwise dead body breathing, is the most resilient part (it has been around the longest, and we're coming to that). It is judged better to let the swelling brain squeeze the life out of the brain stem. OK, brace yourself:

The baby in this photo, originally from The Neuropathology Web at Northeastern Ohio U College of Medicine, seems normal at first glance: it can breathe, suck, wave its arms and legs, coo, and even smile. But it will never see, hear or become human. The backlighting shows that there is no brain in the skull. More accurately, in the condition called Hydranencephaly, the brain stem is present, and perhaps part of the cerebellum, but none of the cerebrum and cortex are present.

Such infants seldom live longer than a few days, though a very few, with care, have lived twenty years or more. They never see, hear, or respond to anything but the painful stimuli that the brain stem mediates. The brain stem is the "reptile brain" that underlies all other brain structures. It has been around the longest, in an evolutionary sense, and is the most resilient. In mammals, the reptile brain has lost the structures that once dealt with seeing and hearing, and yielded those functions to the cortex. This baby has no cortex.

The cerebellum controls gross motions, so if it is entirely lacking the baby won't even wave its limbs. But there are several "superior" structures that have to be present for the infant to learn to eat rather than suck, or even to move the limbs in any coordinated way. Even more of the brain is needed for any trace of "humanness" to exist. A case like this is equivalent to the most damaging head wounds. There is nothing for a doctor to work with, no actual patient whose life could be saved, or even temporarily improved.

At the other end of life (many years later for nearly all of us), the lucky ones are those who die with their wits intact. That is about half of us. For the other half, various degenerative conditions set in toward the end of life, and for most, doctors can offer only "supportive" care. They can help you feel better as you lose your memory and reasoning abilities. This is particularly poignant for me, as I come from a family that is prone to Alzheimer's dementia. Will I be like my mother, who died almost mindless at age 82, or like my father, who is a robust and very intelligent 87-year-old (though he is getting a bit creaky)?

In her last chapter, Dr. Firlik speculates on the future of neuroscience. Will we one day be able to get a "brainlift", at a cost comparable to a facelift? Will the various dementias be conquered? I join her in hoping so.

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