For 10 minutes he will attempt to repair the vessel, but the tissue has given way. Instead, the vessel is sealed off with a series of metal clips. A blood-stained Cerullo leaves the OR to change into new surgical gowns, putting Engelhard back in charge of the preparatory steps. The blood vessel has been sacrificed, but in this case the surgeon is not concerned. ”The brain, unlike the spinal cord,” he explains, ”has many redundancies, and this patient has enough collateral circulation to compensate without adverse effect for the loss of one vessel.”
Meanwhile, Engelhard is beginning the second step of the operation, a two-stage procedure to remove a section of skullbone. For the first stage the normal tool is a $10,000 Smith-Peterson power drill that quickly powers through the one-quarter inch of bone and automatically stops short of hitting the less-resistant brain membranes below. However, this day, the power drill, one of two, is out of commission, and the other is being used next door in OR 8.
The resident will instead use a hand drill to slowly carve out ”burr holes” in the bone. ”This is great for the triceps,” he observes, adding,
”This part of the operation is carpentry and hasn`t changed much in thousands of years, except for the advances in anesthesiology and
monitoring.”
(Thousands of years ago the Incas used sharp-edged metal instruments to cut open the skulls of people who were behaving strangely. These apparently cruel ”trephinations” actually cured some people who were suffering from hemorrhages of the brain`s membranes. By opening the skull, the primitive
”surgeons” allowed the fluid to drain out, relieving the dangerous pressure. The miracle, as evidenced by analysis of recovered skulls, is that the patients did not die from infection. Interestingly, a study done decades ago found that 10 percent of all U.S. patients hospitalized with mental illness suffered from such untreated hemorrhages. Knowingly or otherwise, the ancient Incas–and Egyptians–were on to something.)
Engelhard continues his drilling, sealing the burr holes in Margaret Wilson`s skull with bone wax, first used to prevent bleeding in 1892 by Britain`s Sir Victor Horsley, a pioneer in neurosurgery. In the second stage of removing the bone, Engelhard will use a $20,000 Midas-Rex rotating saw to cut along a line from burr hole to burr hole, making possible the removal of a section of bone approximately two inches square. The bone is stored in saline solution until the end of the operation, when it is sutured back into place with nylon wire. Now a window of brain has been exposed, and only the membranes, a series of three outer envelopes covering the brain and formally known as the ”meninges,” stand between the surgeon and his target.
It is 9:15 when Dr. Engelhard takes a small pair of surgical scissors and, working with headlight and magnifying glasses, gently begins to peel back the dura mater (Latin for ”hard mother”–the three brain meninges are collectively known in Latin as ”mothers of the brain”) from the brain`s other two layers–the arachnoid, named for its spider-weblike appearance, and the pia mater (”faithful or tender mother”), which adheres directly to the brain itself. Because the two bottom meninges are transparent, the stripping back of the dura will expose the brain itself. Upon this exposure, the right hemisphere of the cerebellum or ”little brain” will be dramatically visible. Located beneath the larger cerebral hemisphere, it controls fine-motor skills. The naked cerebellum is an awesome sight: The wondrous organ pulsates with life, quivering with each beat of the heart.
”Now that the stuff Herb would like to do is about to begin,” assistant resident Pollack quips, ”Dr. Cerullo will step in and do the challenging stuff.” At 9:30 Cerullo sits down to the task at hand and begins what will become a marathon day. The music is changed to a classical recital by the Stuttgart Chamber Orchestra, but it may as well not be playing. For 10 hours Cerullo will be a solitary craftsman, intensely engaged in a battle of wills
–his against the tumor`s. Time stands still; there is nothing but the target.
The target is easy to see, and it is easy to see what had caused the bleeding. Margaret Wilson`s tumor is everywhere–protruding from the cerebellum as an angry red-gray mass. Metal retractors costing $5,000 are used to gently push aside the cerebellum and allow the surgeon to work on the tumor.
The challenge will be to remove the entire tumor, ”which has the consistency of carrot-cake,” without hitting the cerebellum or the (out-of-sight) brain stem, the primitive ”reptilian” brain that controls automatic functions like breathing and heartbeat, or any of the delicate nerves and vessels supplying these life-sustaining organs. The tumor must be teased out and removed from the cranial nerves with which it is entwined –cranial nerve 5 (controlling facial sensation), 6 (eye movement), 7 (eye movement and taste), 8 (balance and hearing) and 9, 10, 11 and 12 (swallowing, taste and the involuntary muscles of the heart, stomach, chest and intestines).
The surgeon will be dealing with fractions of a millimeter; the slightest slip can be disastrous. And now that he can see the enemy, he has the answers that the space-age imaging techniques could not give him: The tumor appears to be benign (only a biopsy can confirm this diagnosis), but it is indeed in a very dangerous location. It is not cystic (which would make things easier because when lanced, the tumor`s fluid would wash away and the remaining tissue could be peeled away) but of a maddening consistency that defies a clean removal. It is not separate and self-contained (which would minimize risk to surrounding tissue) but has entwined and indented and insinuated itself with all the normal tissues.
For this case Cerullo needs the surgical tool that he himself has in the past seven years helped pioneer–the laser.
The laser sits beside him, looking humble enough–a mere console, one side linked to two ordinary pressurized tanks of carbon dioxide (CO2) and nitrogen, the other side equipped with an arm articulated into seven segments and looking like a dentist`s drill. But inside that console there works a miracle first conceptualized 75 years ago by the brain of Albert Einstein, who dreamed of ”light amplification by the stimulated emission of radiation,” a theory that today is wondrous reality, known by its acronym, laser.
Inside the console are two separate laser tubes–a carbon dioxide laser and a helium-neon laser. The CO2 laser, a wavelength in the invisible range, is the ”scalpel of light” that will do the cutting or, actually, the vaporizing; the helium-neon laser, which is visible and is similar to
”pointers” used by lecturers, is focused to be coincident with the CO2 laser. Its twinkling red pilot light guides the surgeon.
As the CO2 atoms are stimulated by electrical energy, the electron revolving around the atom`s nucleus of one proton and one neutron spins into outer orbit, traveling faster and faster. Then the excited electron is stimulated with a second and identical jolt of electrical energy. This second jolt stimulates the electron to give up its energy, emitted as a photon of light, and to return to a resting state. This process is multiplied many millions of times, the resulting photons being harnessed in the CO2 laser tube and released as an amplified beam of light that is columnated (the light is in the shape of a column and has a direction), coherent (the waves are synchronous, existing in the same time and space) and monochromatic (one color on the electromagnetic spectrum). The intense laser energy is then directed into the articulated arm, which has a series of seven mirrors arranged at 45- degree angles to reflect the beam. The arm delivers the unfocused beam to either a hand control, which looks like a fountain pen, or to a ”joystick”
bolted to the operating microscope. These controls enable the surgeon to focus the beam into a precise cutting tool. The CO2 laser is brighter than sunlight, capable of zapping through steel and is easily absorbed by water. Given that the brain is 80 percent water, the CO2 laser has become the laser of choice.
Northwestern Memorial`s Cooper Lasersonic 870 CO2 laser costs $120,000 and is the workhorse of Cerullo`s practice. It is backed up by a $100,000 Molectron Nd:YAG laser (an acronym for neodymium, yttrium, aluminum, garnet), which is particularly useful in coagulating blood during small-vessel work. So new is the technology that a manufacturer`s representaive for the Nd:YAG is standing by should a question about the machine`s operation or a malfunction arise.
In using the laser on Margaret Wilson`s tumor, the neurosurgeon will also use the ceiling-mounted operating microscope, itself a device that came of age in the 1970s. The surgeon`s entire work on Margaret Wilson`s brain will be done within the confines of a 3/4-inch-square surgical ”window.” But the $90,000 scope magnifies the view 25 times and presents it in three dimensions. Overhead, a TV camera shows the surgical opening, but it is little more than shadow and light compared to the magnified 3-D view the surgeon sees through his eyepieces. The scope`s focus and all its other controls are built into a $50,000 operating chair, but, unfortunately, the focus on this scope is not working. Cerullo calls for a new chair, and within seconds nurses have wheeled in one that works.
The surgeon settles into his chair and moves up to the scope eyepieces. In his hand he holds the scope`s joystick, resembling the controls used on airplanes and video games. He activates the laser with a foot pedal.
As Cerullo guides the beam with the joystick, his own brain must play tricks with reality. The CO2 laser is invisible, but the helium-neon pilot laser indicates where the CO2 laser is striking. But there is absolutely no tactile feedback, usually the surgeon`s guide: Cerullo must imagine from what he sees exactly what the laser is doing.
Cerullo`s brain is orchestrating four different notes on the laser:
Controls on the console select laser wattage–1 to 80–and continuous or pulsing modes; the foot pedal controls the duration of the beam; a
micromanipulator on one side of the joystick can focus the laser beam to target areas of tissue as small as 1/50th the thickness of a human hair–fine enough to vaporize one cell at a time; and a micromanipulator on the other side of the joystick adjusts the laser`s impact zone, changing from a target of a few cells to a much wider area. The surgeon ”unconsciously” works the various controls to get the effect his mind tells him is right. ”With laser, what you see is what you get,” he explains, ”but it`s a lot like programming a robot to shake hands. Too much and you`d break someone`s hand; too little and the person would never feel it.”
On the overhead TV, an observer can follow the movement of the pilot light, but it is difficult to understand what is happening. Tissue is being changed, but there is an eerie, other-worldly quality to it. One does not see the usual picture of tissue being manipulated–pulled and tugged and often traumatized.
Every time Cerullo presses the foot pedal and aims the laser beam, a cell –or many cells–of Margaret Wilson`s tumor heat up past the boiling point and explode into gray vapor. Like magic, the tumor literally is disappearing. Because the CO2 laser is easily absorbed by water, there is little danger of its being deflected onto normal tissue. And because it coagulates the tiny blood vessels it passes through, there is little risk of bleeding. The healing light can coagulate, vaporize and weld.
But the surgeon still cannot afford a false move. The laser can, if misdirected, just as easily burn through vital tissue or even, with devastating effect, strike through to the brain stem.
Laser neurosurgery is not a magic wand. The surgeon must be skillful and intensely vigilant. In Margaret Wilson`s case, this vigilance will extend for hours, through three shifts of nurses, two shifts of anesthesiologists, two shifts of brain-monitoring technicians and two shifts of neurosurgical residents.
Cerullo alone will remain, glued to his operating scope (later he will apply a salve to the rub burns beneath his eyes). For hour after hour he will battle the tumor with the tools of his trade–the CO2 laser, the nonstick bipolar coagulator (refined at Northwestern to cauterize and control bleeding) and the suction aspirator. Alternately, he will burn off tumor, coagulate the tiny normal blood vessels nearby and suck up the blood, smoke and tissue. He later will tell Margaret Wilson that brain surgery requires some of the same attention to detail and concentration as needlepoint.
Some neurosurgeons criticize the use of laser because it offers no tactile feedback, chars the tissue (making it hard to tell tumor from normal tissue) and is slow–very, very slow.
Cerullo regards slowness as a virtue. ”Gentleness counts,” he says,
”because all that pulling and tugging traumatizes normal tissue. Sure, there are other tools that can remove tumors more quickly, but that`s not the touchstone. The touchstone is how long the patient will live afterward without adverse effect. ”I have an aunt who has been paralyzed for 40 years. She had a brain tumor and was operated on by one of the leading surgeons in the country. He used the accepted technique of the time–removal of the tumor with the index finger. The index finger! That`s why I`m in this business, to try to get better results every time I operate.”
A biopsy sample has been sent to pathology, and now a nurse`s voice rasps over the intercom: ”The sample is too charred and too small for definitive diagnosis. Can you send a larger sample?”
