Firlik - Another day in the frontal lobe: a brain surgeon exposes life on the inside

Contents

For Andy

ONE

Scientist and Mechanic

The brain is soft. Some of my colleagues compare it to toothpaste, but thats not quite right. It doesnt spread like toothpaste. It doesnt adhere to your fingers the way toothpaste does. Tofuthe soft variety, if you know tofumay be a more accurate comparison. If you cut out a sizable cube of brain it retains its shape, more or less, although not quite as well as tofu. Damaged or swollen brain, on the other hand, is softer. Under pressure, it will readily express itself out of a hole in the skull made by a high-speed surgical drill. Perhaps the toothpaste analogy is more appropriate under these circumstances.

The issue of brain texture is on my mind all the time. Why? I am a neurosurgeon. The brain is my business. Although I acknowledge that the human brain is a refined, complex, and mysterious system, I often need to regard it as a soft object inhabiting the bony confines of a hard skull. Many of the brains I encounter have been pushed around by tumors, blood clots, infections, or strokes that have swollen out of control. Some have been invaded by bullets, nails, or even maggots. I see brains at their most vulnerable. However, whereas other brain specialists, like neurologists and psychiatrists, examine brain images and pontificate from outside of the cranium, neurosurgeons boast the additional manual relationship with our most complex of organs. We are part scientist, part mechanic.

The scientist in me revels in the ethereal manifestations of the brain: the mind, consciousness, memory, language. The mechanic in me is satisfied by the clear fluid that rushes out of the end of a tube I insert into a patients brain to relieve excessive pressure. In everyday surgical practice, the science may take a backseat to the handiwork, and thats okay. If you have an expanding blood clot in your head, you want a skilled brain mechanic, and preferably a swift one. You dont care if your surgeon published a paper in Science or Nature.

Ill give you an example of a most straightforward and manual case. I was paged to the emergency room a few years ago during my training and received the following brief report over the phone: carpenter coming in with a nail stuck in the left frontal region of his headneurologically intact. What is going through my mind at this point? Do I hark back to my studies of frontal lobe circuitry and mull over the complex neural networks involved in language and memory? No. Im thinking concrete, surgical thoughts: nails are sharp; the brain is full of blood vessels; the nail may have snagged a vessel on the way in. These thoughts are instantaneous, of course. I spell out the simple logic here purely for effect.

What I encountered in the ER was a young man, in his thirties, sitting up on an emergency room gurney. Perfectly awake and alert, arms crossed in repose and still in his construction boots, he smiled nervously when I walked in. Was he the right patient? He looked too good.

He was the right one. The carpenter explained that he and his friend were both on ladders along the side of a house. His friend was working a few rungs above. They were driving heavy-duty nails into the siding with automatic nail guns. His friends hand slipped upon firing in one of the nails, and the nail entered the left frontal region of my patients head below. For the first few moments after impact, the carpenter doubted what had happened. Although he noticed a stinging sensation within a split second of his friends slip of the hand, and heard the loud expletive coming from the same direction, there was no trickle of blood and he felt nothing unusual as his fingers frantically searched the top of his head. He wasnt sure if it went in. His friend knew otherwise.

Upon close inspection of his scalp, past his short crew cut, I could see the flat silver head of the nail, not quite flush with the scalp, but a bit deeper. Apart from the nail, he looked great. I performed a quick five-minute neurological exam and found nothing wrong. I sent him down the hall for a CT scan. The nail entered his brain perfectly perpendicular to the surface of the skull. It had been driven a good two inches into his left frontal lobe. Luckily, it didnt snag any sizable blood vessels along the way. There was no evidence of bleeding within the brain. Unlike the more common gunshot wounds we see, this was a respectably neat and clean penetrating injury.

At this point, my biggest fearbleeding in the brain from entry of the nailhad been put to rest. Now, do I take a breath and mull over any complex scientific issues at this point? Am I exercising my formidable brainpower as a brain surgeon? When people say, it doesnt take a brain surgeon, they refer to the assumption that we are the smartest ones around. Have I demonstrated this superior intelligence so far? Again, my thoughts return to the practical and concrete. We need to get the nail out of this guys head. It didnt cause any bleeding on the way in. We need to avoid bleeding on the way out.

I walked out to the waiting room. His wife was there and so was his friend, who was pale and despondent, looking down at the floor. I tried to cheer them up a bit. Yes, the nail entered his brain, but his brain function, as far as we could tell, was normal and the nail caused no bleeding. Without looking up, the friend opened his hand and offered me a large silver nail that had been warming in his palm, the same type embedded in my patients head. I dont knowit might help you guys to have one of theseso you know what youre dealing with. I hadnt been able to tell from the scan that the nail had two copper-colored barbs sticking out from the shaft at acute angles. Im not a carpenter, but I figured that the purpose of the barbs was to ensure a strong hold. I thanked him and pocketed the nail in my white coat. On my way back to the ER, I ran my fingers over the pointy barbs and thought about the issue of bleeding again. Avoiding and controlling bleeding are elementary and pervasive themes in surgerynot quite the stuff of rocket science, but critical nonetheless.

After calling on the appropriate team, including the supervising neurosurgeon and anesthesiologist, I took him to the OR, shaved a small patch of hair around the nail head, and made a short linear incision in his scalp, down to the skull. There are no how-to entries in our textbooks regarding removing nails from heads, so we improvised using common sense. We drilled out a disc of frontal bone from his skull, with the nail head at the center of the disc. Slowly, we lifted this piece of bone up away from the surrounding skull, bringing the firmly embedded barbed nail with it. Although we could see a small jagged tear in the covering of the brain and a puncture wound on the surface of the brain itself, there was no blood oozing from the hole, and we considered ourselves lucky. (Better lucky than good is a favorite slogan among surgeons.)

Then, using large tools fit more for our patients line of work, we clipped off the barbs and pounded the nail through the disc of skull, backward. After soaking the bone in an antibiotic solution, we neatly plated it back in place with miniature titanium plates and screws and sewed his scalp back together. Actually, rather than suture, we used surgical staples from a staple gun to close the final layer of his scalp, unaware, at the time, of the subtle irony in that move. Within less than twenty-four hours, the patient was on his way home, joking the entire length of the hall with the friend who nailed him in the head.