Experts in ear surgery debated the merits of the endoscope in a panel session at the Triological Society Combined Sections Meeting, a discussion that centered largely on the two-handed maneuverability available when using a microscope versus the improved visualization gained when using an endoscope, which leaves just one free hand for the procedure.
Explore this issue:March 2017
Abraham Jacob, MD, associate professor and vice chair of otolaryngology and director of the University of Arizona Ear Institute in Tuscon, Ariz., said the endoscope has led to a more intimate and detailed look at the structures of the middle ear space, such as the retrotympanum and its associated structures, like the proximal portion of the intratemporal facial nerve. This new understanding paves the way for more precise and effective surgery, he said.
Because using an endoscope allows surgeons to sit in a more upright position, as opposed to the more head-forward position required for using a microscope, there may be less strain on the neck, he added. “A lot of people worry about the learning curve, but it’s not too bad,” Dr. Jacob said. “Even my very first case, where I thought I would just be raising a [tympanomeatal] flap, I ended up doing the whole tympanoplasty with the endoscope.”
He made these suggestions for surgeons just beginning to use the endoscope:
- Start using standard otology instruments and a 14 cm-length, 3mm-width, 0-degree endoscope.
- Perform your first set of endoscopic procedures on light OR days.
- Start by using just your standard otology instruments.
- Start with simple procedures, such as a straightforward tympanoplasty or even pressure equalizer (PE) tube insertions.
- Be sure to use adequate anti-fog so the scope doesn’t cloud up.
- At first, try using the endoscope only for portions of the surgery with which you’re most comfortable.
Anterior Tympanic Membrane Perforation
Michael Hoffer, MD, professor of otolaryngology and neurotology at the University of Miami in Florida, advocated for using the microscope. “It allows you to use a two-handed technique, and it gives you 3-D vision,” he said.
He said that the lateral graft procedure has been shown to produce the best results for anterior tympanic membrane perforations, but a case involving a lot of bleeding can be very difficult using an endoscope. “I don’t see in this particular case where you would be better off using the endoscope,” he said.
Alejandro Rivas, MD, associate professor of otolaryngology and neurological surgery at Vanderbilt University in Nashville, said that using differently angled scopes can help the endoscopic procedure match the ease of using a microscope. The mobility of the endoscope means that the patient can stay in the same position. “We don’t have to turn the head,” he said. “Ergonomically, for the patient, it’s good. And, ergonomically, for you, it’s good.”
“In children, it’s ideal,” he added. “Very rarely the size of the ear canal matters. You can repair perforations as early as 4 years old. You barely have to put any packing after surgery.”
He said he doesn’t use lateral grafts, but the underlay-overlay technique works well; the hardest part is raising the flap, for which he uses suction. “A lot of time that you spend doing these cases at the beginning, pays off at the end,” he said.
Lawrence Lustig, MD, Howard W. Smith Professor and chair of otolaryngology-head and neck surgery at Columbia University in New York City, said he can generally perform the typical otosclerosis procedure in 30 to 45 minutes.
“Is the endoscope the next step in our evolution? I really don’t think so,” he said. “I don’t think anybody in this room can argue that you get better visualization with an endoscope than you do with a microscope. The real crux of the matter is what’s better: one-handed surgery or two-handed surgery? … I personally would rather be a two-handed surgeon when I’m manipulating my ossicular prosthesis.”
He added that he thinks the visual quality of today’s microscopes shouldn’t be downplayed. If tools were developed to allow two-handed endoscopic surgery, he might be more interested, he added.
Dr. Jacob said that the one-handedness is outweighed by a “dramatic difference in the view that you get.… The chorda tympani is essentially untouched.”
He added: “Once you get the visualization it’s tough to go back to the microscope. Early on, there’s a lot of nervousness related to the technique and not being familiar with things. But then as time goes on, you get familiar and get used to that view.”
Attic Cholesteatoma Procedures
Dr. Rivas said that he would tend to do anterior, posterior, and lateral epitympanic cholesteatoma with an endoscope. But he added that lateral procedures are those for which the endoscope offers the least advantage.
The need for a mastoidectomy, for which a microscope is more likely to be required, has to be assessed in each case, and, at Vanderbilt, they’ve been able to avoid unnecessary mastoidectomy in about 40% of cases, he said. Using an endoscope can also help preserve the ossicular chain, which means better hearing. Controlling heart rate and mean arterial pressure so that there is less blood output, and controlling the intensity of the light for heat reduction, are important, too, he said.
Patients—and especially parents of children undergoing surgery—appreciate the endoscope “tremendously,” he said. “They love the fact that they can understand what they’re seeing, as opposed to just trusting the doctor about what they’re seeing. They can actually see it.”
Dr. Hoffer said that mastoidectomy might be needed more often than Dr. Rivas suggested. They can be needed not only for removal of disease, but also for aeration of the cavity for better long-term results.
He also drew attention to potential problems with heat. “If you’re focusing in detail with an endoscope, there is a heat concern,” he said. It hasn’t been shown that hyperthermia causes harm, he said, but it has been shown that hypothermia reduces harm.
Controlling the heat can mean moving the endoscope frequently, adding time to the procedure. “It’s not technology that I avoid,” Dr. Hoffer said. “It’s just that I don’t do it for as many cases.”
Thomas Collins is a freelance medical writer based in Florida.