As a nation of animal lovers, lap of luxury cats with diamond encrusted collars and pampered pooches that eat prime steak are not such an unusual occurrence. Many animal lovers maintain their pet’s health more keenly than they look after themselves, as evidenced by the sizeable market for pet health insurance – but can animals really wear contact lenses?
In fact, therapeutic soft contact lenses have been used by vets to treat eye conditions in animals like cats, dogs and horses since the late 1970’s. Originally designed for human usage, therapeutic contact lenses effectively act like a bandage for the eye, protecting a cornea that is damaged or diseased from the continual friction caused by blinking eyelids. During the period that the contact lenses are in place – in animals this is usually around five or six days, after which time the lenses fall out – the damaged cornea gets time to heal.
It was human therapeutic contact lenses that were first used in animals, which, perhaps unsurprisingly, often made it difficult to find lenses that were a good fit. Things have moved on, and since the 1990s there have been contact lenses specifically produced to fit the eyeballs of different domestic pets, while there have been custom made contact lenses manufactured for a range of more exotic animals, including an elephant!
As well as occasionally needing therapeutic soft contact lenses, pets can also suffer from a range of eye conditions that humans develop, including cataracts. In humans, cataracts are treated by removing the clouded lens within the eye, and replacing this lens with a synthetic substitute. Since around 2005, the same kind of intraocular lenses have been available to treat cataracts in animals. As well as pets like cats and dogs, a performing sea lion at Sea World in San Diego has had cataracts treated with intraocular lenses, as has a blind kangaroo and a number of brown bears in China!
Leaving aside these surgical implants, tinted contact lenses that sit on the surface of the eye are also becoming increasingly popular as a cosmetic solution for dog owners, and can cover up damage or disfigurement to the animal’s eyes. While a range of these contact lenses are now made specifically for dogs of different sizes, measuring the curvature of the cornea prior to fitting is not standard practice (as it is in humans), and so a bit of trial and error is often involved before the right shape of lens is found.