Cambridge, MA, USA
|Photo by Hannah Wilson|
“Nobody can be told what the matrix is, you have to see it for yourself. … Morpheus: If real is what you can feel, smell, taste and see, then ‘real’ is simply electrical signals interpreted by your brain,” Neo, The Matrix, 1999.
Tomorrow was louder than I had expected, the silence of the elevator seemed a distant memory as my ears adjusted to these strange new sounds. Bleeps then clicks, a constant background hum, a crunch as the shape formation molded.
We were invited to tour the facility; step by step the new vision revealed itself. This was a virtual hospital; designed to perform in the same way that a real hospital functions, a dress rehearsal in effect, mistakes could and should be made, practice would make perfect, and patient lives would be saved.
I was introduced to a man who had been recruited from Hollywood where he had worked in medical science fiction before he decided this was “no longer science fiction.” He took me to his office, where I saw two large curved screens reflecting bright red, blue, and green images of a human spine. It looked like the kind of CT image or perhaps even MRI that I had often seen in my anatomy books, only this was imperfect. He explained that this was step one, designing the Computer Aided Design (CAD) image that all models to be printed must begin with and he explained these could take anywhere from one day to two weeks to produce. When I asked him where his designs ended up, he looked at me as if no one had ever asked him this before. “I am not a doctor,” he explained, “I don’t ever see the patients, I just hope that what we do helps someone, somewhere.”
As we talked we watched the spine rotate on itself and compared it to the CAD models of the healthy human spine. The man went on to explain step two and three. Each CAD model was exported to a stereolithography file format (STL), a de facto CAD file format for additive manufacturing that stores data based on triangulations of the surface of CAD models. From here the STL files could be “spliced,” much as genes are spliced in gene editing. I imagined the data being cut and pasted until the file was the allele required. Every vertebra perfectly aligned, every disc perfectly symmetrical, every joint perfectly spaced. At this stage the spliced STL file was programmed and formatted into a code for the printer, a kind of printing that required a new language. The code included the temperature settings, the number of layers required, the speed of the printing process, the percentage of plastic to be used. Much like the spliced genetic code creating shiny perfect genes, instead we had shiny perfect organs, only on a much larger scale.
Spina bifida is a cruel disease, a birth defect where there is an incomplete closing of the backbone and the membranes around the spinal cord; the latter is a vital component of the nervous system and its complete closure and hence protection is essential for healthy human life. Imagining that your brain’s tail (spinal cord) has left the body can be a helpful way to visualise this condition. This future patient’s spine could be 3D printed and used in a simulation surgery to practice and perfect the technique that would be needed to close the spine.
I was then led away from the computers and through several longer corridors and doors into the lab. A handful of people in white coats and goggles filled the room, and the familiar smell of chemicals tickled my nostrils. Science was at work.
Soon we were in a room where whichever way we looked we found large, black, box-like machines staring back at us. There must have been five or six of them in total, spaced out evenly and methodically across the room. Each was a little different from the next; cubes, cuboids, even cylinders (with closer inspection) and I was told each had a slightly different function. These were the 3D printers, this was the place that the computer-generated codes came into life. From a message on a computer, out came a life-like human organ; ready to be used to simulate a surgery.
I learned that each of the printers had single or dual extruders/heads, the latter meaning that the organs could be printed with dual colors or dual materials. I was shown a previously printed model of a cleft palate. The pink colored flesh against the redness of the lips looked almost too real. Opening the printer showed the heating beds. Key to all 3D printing, the heating beds helped the materials stick to each other and ensured that the material did not pop off mid-print. I was told that different percentages of plastic that could be used as well as the usual overhang of the printer which should, for the best results, be positioned at 45 degrees. Every detail must be correct to ensure the organs print perfectly. There were available a large number of additional processes, the main differences between each being the way layers of the material were deposited to create parts and the materials that were used. I was told some companies offered a choice of powder and polymer for the material used to build the object while other companies use standard, off-the-shelf business paper as the build material to produce a durable prototype. Here the lab had been printing a spine since yesterday. I peeked into the large black box and caught my first glimpse. There in front of me was a human spine, neatly forming before my eyes and ready in its own oblivious way to help save a human life.
The surgeon greeted us with a nod, she was “scrubbed in” (a medical term that reflects a surgeon has thoroughly washed their hands and arms to ready for surgery and is now in a sterile field). The blue layers swallowed her so that her hands seemed uncharacteristically large. As she delicately probed around at the bones beneath the blue sheets, it was hard to remember this wasn’t in fact real. As the scalpel pierced the skin (molded plastic) and blood oozed out (a careful composition of fluid) it was alarming to think that all this was just a rehearsal. Our future patient was safe. The surgeon explained how these 3D printed organs had revolutionized her training. She could now practice detailed and intricate procedures over and over again knowing that she could make the mistakes required, to ensure that when the time came, there would be none. The sheer disbelief in her voice echoed my thoughts; how could the organs look and feel so real? Not just to the naked eye but to the scalpel and to the hands of a highly trained surgeon. Whilst she knew this wasn’t a real human spine she was looking at, she explained sincerely that for all intents and purposes that to her, it was. The room was akin to the operating room (OR), the spine mimicked the one she would soon operate on. The simulation lab was even able to design bodies to fit the spine. Complete with skin, hair, and teeth in an effort to make the whole process feel like it was human, it needed to look human, they needed to feel it was a human.
Some years ago, while writing an article about the future of medicine, I dreamt of robotic surgeries being operated in one country yet performed in another. I imagined instantaneous results from the microchips we all had inserted into our bodies at birth and I pondered at the personalized drugs available once we had all had our genomes sequenced. As I collected the warm sheets flying off the printer, never did I imagine that one day soon, I would instead be printing organs.
“I’m trying to free your mind, Neo. But I can only show you the door. You’re the one that has to walk through it.” Morpheus, The Matrix, 1999.
HANNAH C.P. WILSON, MD, is an academic junior doctor, currently studying for MMSc in Medical Education and has a specialist interest in innovation and training at Harvard Medical School. She currently writes a blog about the training of Junior Doctors in the NHS. Her past work has appeared in the BMJ and the BMJ blog.