It was September 2012, Kate Mark and her nine-year-old Quarter Horse mare Sukuria entered the ring at the Beaverton Fair. They picked up speed, then aimed toward the first barrel, but Sukuria took a wide turn.

It was uncharacteristic of the careful mare that Kate had owned since she was three years old. But Kate didn’t have time to think about the misstep as they headed toward the second barrel. Here, Sukuria made another mistake, coming so close she knocked it.

The pair finished the class and ran another one. The same thing happened. “She was running sloppy. I knew something was up,” said Kate.

After examining her, Kate noticed that the mare’s left eye appeared cloudy and blue. When they returned home, she called her local vet, who prescribed eye ointment. But Kate wanted more answers, so her vet recommended she consult Dr. Bruce Watt.

After trying treatments like Atropine eye drops and Tobrex, and seeing no improvement, Dr. Watt diagnosed Sukuria with equine recurrent uveitis – a confounding but common eye condition that has no cure.

In ERU, the horse’s immune system has gone awry and attacks the tissues of the eye. The horse will squint, have tears, and her eyes will become sensitive to light. The cornea will be blue or cloudy. The damage to the eye is progressive and some horses – like Sukuria – ultimately go blind.

Sukuria’s vision in her left eye went first. But there was still pain and discomfort. “It was obvious it was a painful eye. It was so inflamed,” said Dr. Watt. “In some horses, it’s like having a toothache or a sore arthritic knee. A uveitis eye – it’s painful.”

According to Kate, the chronic pain had changed Sukuria’s personality. “She was grumpy with her field mates,” said Kate, who likened the pain Sukuria was experiencing to a chronic migraine.

Together, Kate and Dr. Watt decided the best course of action was to remove Sukuria’s left eye – a procedure known as an enucleation. Removing one eye isn’t a big deal – Dr. Watt said he has removed several in the more than 30 years he’s been practicing veterinary medicine. And surprisingly, he says, most horses adapt quite well to the loss of vision on one side.

Sukuria was no exception. Kate continued to ride the mare and bred her. But as time progressed, the ERU returned – in Sukuria’s right eye. The progression was much the same. The afflicted eye didn’t respond well to treatment. As Sukuria’s remaining eye deteriorated and the mare faced an increasingly dark world, Kate noticed she latched on to her pasture mate – a section A welsh pony named Gemma. “Gemma would take her to the water trough and take her to the barn. They started getting really close to each other,” said Kate.

In 2016, Sukuria went fully blind. People advised Kate to euthanize the mare, concerned it wasn’t safe to have a blind horse. And as with the left eye, the right eye was now doing nothing but causing pain.

Kate consulted with Dr. Watt, who, instead of recommending euthanasia, suggested removing the right eye, too. “I just don’t see the rationale in euthanizing a horse that’s already completely blind and adapting well,” he said.

Dr. Watt removed Sukuria’s right eye in August 2016, and life has continued as normal for the mare and Kate.

She said she still rides Sukuria, and has taught her voice commands like “step up” and “step down.” To load her in the horse trailer, Kate taps the trailer twice and says “trailer.”

Since Sukuria has been blind, Kate has taken her to the lake, horse camping and participated in the Christmas parade in Beaverton.

Kate admits that “every now and then” she wonders if riding a blind horse is dangerous, but because it doesn’t seem to bother Sukuria, she figures it should be fine with her as well. “It depends a lot on the horse,” she said. “I have horses here who there’s no way they could be blind and live a normal life. It’s really horse dependent. I’ve spent 10 years with this horse; I know exactly how she is.”

As long as Sukuria is safe and happy, Kate will continue to enjoy her horse.