From its early role in veterinary medicine as a minimally invasive way to get a better look at internal anatomic workings, endoscopy has developed into a burgeoning array of structural versions and medical and surgical applications.
“I sometimes think, why should we as veterinarians talk about and learn these types of techniques?” said Kathleen Ham, DVM, assistant professor of small-animal surgery at The Ohio State University College of Veterinary Medicine. “I can break this up into two different categorical reasons: veterinary medical and client-driven.”
Clients are requesting this level of minimally invasive surgery, said Dr. Ham, a Diplomate of the American College of Veterinary Surgeons.
“Minimally invasive surgery has become the standard of care in people, and many clients have had it or know someone who has, and they believe that it is an easier type of surgery to recover from,” Ham said.
On the medical side, endoscopic surgery results in decreased patient morbidity, Ham said.
“The patient has a smaller incision, which results in less pain, less chance of incisional complications and infection, less bleeding, less ileus, decreased recovery time and decreased hospital stays,” she said.
“From the surgeon’s perspective, we have magnification, better illumination, and the procedures can be recorded or have digital pictures saved, allowing for documentation,” she added.
Not Just for Small Animals
“Gastroscopy is the gold standard for diagnosis of gastric ulcers, and endoscopic biopsies can be obtained from the stomach and duodenum,” said Dr. Mudge, associate professor of equine emergency and critical care at The Ohio State University College of Veterinary Medicine.
“Transendoscopic laser procedures can sometimes take the place of open approaches for upper airway surgery, and endoscopy also complements traditional surgery approaches to the upper airway and paranasal sinuses,” she said.
In horses, a new trend is dynamic overground endoscopy, which allows upper airway evaluation in the exercising horse without the need for a high-speed treadmill, Mudge noted.
The clinician can view the anatomical structures in a more natural position as the horse runs on a track, explained James Burns, managing partner of Endoscopy Support Services Inc. in Brewster, N.Y. The horse doesn’t have to be trained to run on a treadmill, so it is potentially safer to use, he said.
In dynamic overground endoscopy, the scope attaches to the horse’s headgear, be it bridle, halter or harness, Burns said. The malleable insertion tube endoscope feeds into the horse’s nostril, and another line feeds back to a unit on the horse—usually a saddle blanket. As the horse runs, the unit records what the scope sees, and remotely transmits the image to an offsite control computer for viewing. Commands for the endoscope on the horse are relayed through the computer on the ground.
“You can even clean the lens remotely,” Burns said.
After an initial bit of “finicky-ness,” horses generally don’t seem to object to the endoscope, Burns said.
“The animal is more comfortable, and it’s safer for everyone involved,” he said. “You get better diagnostics and better imaging,” he said.
Newer ESS systems have a “quick disconnect” feature, which enables the user to remove the equipment from the horse in one motion and avoid a scenario where one detached portion can whip around and frighten the horse, Burns said.—LAE
Laparoscopic ovariohysterectomy and ovariectomy are common procedures performed with a rigid endoscope, said Chelsea Corwin, marketing associate with Karl Storz Veterinary Endoscopy America Inc. in Goleta, Calif. Beyond spay surgeries, indications for rigid scopes include rhinoscopy, laryngoscopy, bronchoscopy, otoscopy, thoracoscopy, arthroscopy, cystoscopy and colonoscopy, according to a Karl Storz brochure. They’re even used in celioscopy in lizards and sex determination in birds.
Flexible endoscopes are generally used in the gastrointestinal tract (esophagogastroduodenoscopy, colonoscopy) and respiratory tract (tracheobronchoscopy, laryngoscopy). It’s possible to use both rigid and flexible types on a single procedure, as Markee Kuschel, DVM, is doing at Deer Creek Animal Hospital in Littleton, Colo.
“In cystotomies, we use the 0.9mm flexible scope in conjunction with a rigid scope,” she said. “With the rigid scope, we can remove the stones confined in the bladder. Then we take the flexible scope through the urethra and get out the rest.”
That 0.9mm flexible “Needleview” scope is manufactured by BioVision Technologies in Golden, Colo., and so far is the finest-gauge diameter scope on the market, according to Robert Blaise, BioVision’s director of veterinary business development.
“The 0.9mm scope allows us to evaluate very tiny spaces without creating added trauma,” Dr. Kuschel said. “I have used the Needleview scope in cat nostrils for rhinoscopy and have evaluated the middle ear.”
At Deer Creek Animal Hospital, rigid endoscopy use outnumbers flexible endoscopy by nearly a 50-to-1 ratio, Kuschel said.
“When you have a rigid scope, you can do different things with it, because there are different sizes, angles and ports, while flexible scopes are more limited,” Kuschel said.
Kuschel said key points favoring laparoscopic spay surgery are less patient pain and greater visualization.
“The value of these is immense,” she said. “I once found a missing kidney during a spay, and I would never have seen that using the conventional method.”
The Power of Technology
For minimally invasive surgery—where a single incision allows access for the scope, whose working channel carries the instrument—the possibilities are impressive.
A new technology offered by Karl Storz is the Telepak Vet X, which combines a monitor, camera, light source, insufflation and image capture device into one portable unit, Corwin said.
“This is a great option for those who need all of these items but are more cost-conscious,” she said.
Ham, of Ohio State, said the newest technologies now in use include vessel-sealing devices such as the LiagSure by Aragon Surgical Inc. of Palo Alto, Calif.
“This instrument can seal tissue and blood vessels and cut the tissues, making dissection and surgery faster and easier,” she said. “A simple ovariectomy can be done without having to suture or clip the pedicle, leaving no foreign material in the body.”
Another newer instrument is the single incision laparoscopic surgery port, where three separate cannulas can be used in one port.
“This means you now have one small incision versus two to four small incisions,” Ham said.
Endoscopy Support Services Inc. in Brewster, N.Y., developed a scope that replaces the traditional endoscopy tower with a medical-grade, portable battery-operated light source. It’s called USB (universal serial bus) endoscopy, said James Burns, managing partner.
“Now you can use a laptop computer, USB camera and a battery-operated light source,” he said. “It lowers the cost and the amount of space used, and it’s more affordable for a general practice to offer this quality medicine.”
A USB camera is “pure digital,” Burns said. “With the traditional towers, everything is analog-to-video, printer, recording device or TV. It’s a lower image quality. Now, our $5,000 USB camera has image quality equal to our $40,000 three-chip laparascopic system camera.”
Ham noted that endoscopic technology has pros and cons, starting with the equipment commitment.
“It is expensive to start a minimally invasive surgery program, and the equipment takes up space,” she said. “There is also a learning curve associated with using an image-guided procedure—that is, watching a screen and moving your hands.”
In Ham’s view, “Veterinary medicine will continue to use and explore options for endoscopic surgery.”
“It really is used for about everything,” Kuschel said. “We’ll say, ‘Here’s something—let’s use the scope,’” as happened recently when a cystoscope enabled her team to locate a fungal infection in a dog’s nostril.