Dr. Mary Utter was charmed the moment she saw her patient in late January, 2010. “If you have never seen a baby alpaca, it is just the most adorable thing. All curly and poufy, with those big, dark eyes.” But it was those eyes that caused the concern. They weren’t dark and glossy, the way the eyes of a three-and-a-half-month-old cria, as a baby alpaca is called, should be. Star Dancer’s eyes were cloudy at the center. This baby was born with cataracts.
A cataract is any opacity of the lens in the eye and can occur at birth or develop with age for a number of reasons. In either case, cataracts impede vision from a minimal amount to completely. Star Dancer appeared to be almost totally blind from birth. At home she clung close to her mother and was disinterested in interacting with the other crias in the herd. Though they reported that she could get around “well enough” and her vision wouldn’t impact her function as a producer of fine fibers, owners Jim Bajzath, Bonnie Belfiore and Doug Kittrell felt that Star Dancer’s quality of life was compromised. And so, they came to New Bolton Center to investigate the possibility of cataract surgery.
“Such a surgery is not common in camelids [the family of animals that includes camels, llamas and alpacas],” says Dr. Utter, “because the significance of visual ability is usually dependent on the needs of the animal.” People have cataracts removed and vision correcting lenses inserted at the same time. And they frequently elect to have the same surgery performed on their dogs. Horses typically undergo cataract surgery at New Bolton Center because sight is such a crucial part of so many of their activities. Imagine jumping a five-foot ditch with a compromised depth perception, or negotiating a racetrack at 45 miles an hour with fuzzy vision.
One of the unique aspects of veterinary ophthalmology, according to Dr. Utter, is that, unlike with other specialties, treatment of eye diseases and conditions is successful across many species simply because the anatomy of the eye is similar in so many types of animals. Since she began practicing, Dr. Utter, a board-certified veterinary ophthalmologist, has performed eye exams or surgery on a pit viper, crocodile, Siberian tiger, hyacinth macaw, kangaroo, zebra, chinchilla, as well as the domestic pets and farm stock. Her practice has been limited to New Bolton Center since 2006, and here she has operated almost exclusively on equines, bovines and, yes, camelids.
When Star Dancer arrived at New Bolton Center in early February, she presented in general good health. An ophthalmic examination revealed an absence of a menace response, where the hand is rapidly pushed towards the eye without making contact; a normal response would be to blink or pull back at such a threat. Dazzle and pupillary light reflexes in both eyes, however, were positive, suggesting that the retina was functioning properly. The eyes appeared to have no abnormalities other than the cataracts, and the likelihood that the cria’s vision would be corrected with surgery was good. In her stall, Star Dancer walked in circles, her head tilted upward. Routine phacoemulsification or removal of the cloudy lens material was recommended.
The surgery, even though it is a common procedure, is technically difficult. Performed under a surgical microscope, a small incision, about the diameter of a pencil eraser, was made in the cornea, described by Dr. Utter as “the windshield of the eye.” The cloudy portion of the lens was broken down with high speed ultrasound and then suctioned out. The opening was closed with an absorbable synthetic suture material about the diameter of a human hair. Anesthesia plays a particularly crucial role in cataract surgery. Because of the delicacy of the surgery, there is no tolerance for movement of any kind. Hence the patient is anesthetized to simulate paralysis, and is temporarily placed on a ventilator to assist with respiration. “Intubating a camelid can also be a bit tricky, both because of their conformation, with those long necks, and the unique structure of the larynx and trachea.”
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