Before the invention of the computer and the CD-ROM, medical students learned surgical procedures by studying textbooks, practicing on cadavers and watching other surgeons. Now, with even more advanced technology than the CD-ROM, med students can learn some of the most delicate operations on virtual simulators.
Surgery on the temporal bone often is considered one of the most challenging procedures a surgeon can master. It involves tiny ear bones responsible for hearing and balance, and important nerves, like facial nerves, that control a person's expression.
At the Ohio Supercomputer Center on Kinnear Road second year Ohio State medical student Dinah Wan sits in front of a computer screen. She holds a plastic wand that's a little larger than a marker she might use to highlight passages in her textbooks. The wand is supposed to be a drill. And on the screen is an image of a diseased temporal bone. And in real time, like a video game, Wan removes the diseased area from the bone. The goal: not to drill too deeply and to avoid important nerves and structures.
It's too early for Wan to have chosen a specialty, like otology - the study of ear and throat diseases, but she's already getting practice on the surgical simulator that was developed to help train resident surgeons.
"She'll know all her anatomy and she'll be an otologist before she get's to ear, nose and throat residency."
Ohio State associate professor of otolaryngology Gregory Wiet joked about Wan becoming a bonafide surgeon before she starts her residency. Advanced technology like this simulator is more common among medical students.
Traditionally, Wiet said student surgeons learn by reading, observing and practicing on cadavers and later on, living patients. Wiet said the simulator just makes sense and in some ways is better than a cadaver.
"Well, it's different in the fact that you don't have to deal with live, human tissue or dead human tissue, if you will. And so there's obviously concerns involved with working with human tissue. Certainly there's much more preparation: you have to obtain the specimen, you have to prepare it. And then there are a whole slew of things that have to be done with respect to operating on it and cleaning up afterwards," Wiet said. Not to mention a student is tied to a cadaveric lab.
"You can't just sort of set it up on your kitchen table and start practicing," he said.
Simulators like these also provide endless practice. Wiet said students get more than one try unlike on a cadaver. With the cadaver, once an area has been drilled that's it - a student can not go back and try a different technique. Another advantage, Wiet said, is simulators measure performance.
"The way that people are graded or assessed with their skill is essentially by an expert observing what they do, and giving a subjective assessment of their performance, whereas, when they're working in the simulator, the simulator can calculate and measure certain things objectively," Wiet said.
Two cadavers lie on tables in the basement of the Ohio State clinical skills center. About five Ohio State medical students and a surgeon crowd around each body to learn about a procedure to remove fluid from different organs and body cavities.
Third-year OSU med student Brian Culp is across the hall from these students. He'll soon head into the cadaveric lab himself.
While Culp has not used the temporal bone simulator he has worked on other simulators. He said they have improved, even since he started medical school, and he underscores Wiet's point about performance measurement.
"The anatomy is improving, the touch of the skin is improving, the whole feel of the process is improving. And the one benefit that I would say is most different is you get feedback from a simulator that you don't get from a cadaver," Culp said.
That sense of touch is important. Surgeons rely on it and the simulators are getting better at imitating the "feel" of surgery . When students use the temporal bone simulator the drill vibrates in their hand and they feel the resistance on the bone. Dr. Wiet said that was a major focus when developing the software. "As surgeons we interact more so with the sense of touch or haptic feedback along with the visual. And as you advance in years you probably depend a lot more on your haptic sense of touch especially in a procedure like ear surgery than you do early on. So that was something that we knew that we really needed to provide in the simulation," Wiet said.
Medical student Wan said she has not worked on a cadaver so she can not compare the two. But Wan said has watched a real temporal bone surgery performed on a video and she recalls it looked quite a bit different than the bone she drills on in the simulator.
"When I saw a video of the real surgery the colors were less, I guess, defined. But then they also had like water and blood coming out and I think one of our people here in working on that. We didn't have that aspect of it," Wan said.
Wiet admitted numerous improvements need to be made on the simulator. But he said he thinks it will benefit surgical students' training later on.
"They could practice over and over again in the simulator in a more or less non-threatening environment. And then they can then move over in to using the cadaveric specimens which would be closer to reality. But they would get much better use out of that human tissue than they would've if they just sort of started that kind of early on," Wiet said. With the increased use of surgical simulators for training the question must be asked will cadavers one day become obsolete? Ohio State Associate Dean for Medical Education Daniel Clinchot said he no. Because surgeons must be able to work with the real thing. "As long as we have to touch and invade someone's body the simulation will never replace the human cadaver," Clinchot said.
Wiet said the temporal bone simulator is still being finely tuned. The Supercomputer Center has developed seven or eight. Many of them are at other institutions.