Roxi regained vision in the treated eye, and Grozdanic and Chelsen had discussed treating her other eye. But at the same time, Roxi’s breathing was also getting worse, and she did not have long to live.
In her last weeks, with her eyesight back, Roxi was able to enjoy some of her old habits. Shortly before Roxi’s death, Chelsen said, “The other day she went and chased a squirrel, and she hasn’t done that forever.”
Grozdanic was able to determine the cause of SARDS and IMR by analyzing donated canine eye tissue, and that information helped him determine what treatments to try. The donated tissue came from a dog who, during his life, also suddenly went blind. Chelsen says the generosity of that pet’s owner motivated him to have Roxi undergo the experimental treatment. “We’ve got a lot of eyesight…because of that woman,” he says. “Why not carry this on?”
In dogs who received steroids or immunoglobulin by the old method—the treatments delivered all over the body rather than just in the eye—results were less dramatic. Still, for dogs, whose other senses help them cope, Grozdanic says even modest recovery of retinal activity is a great help. “I mean, there is no vision at all, and even if we get five percent, for a dog, that can mean a lot in terms of improving quality of life, and that’s our goal. Everything that we get above that basic five percent is great,” he says.
Although both blindness diseases—SARDS and IMR—are characterized by sudden blindness, they differ in their mechanism. In SARDS patients, antibodies are produced only in the eyes, while in IMR patients, they’re produced throughout the body. In the past, SARDS was recognized but the cause was unknown. Now that Grozdanic has published his discovery of what’s causing SARDS and IMR, he’ll continue testing the intraocular injection that showed promise with Roxi.
Grozdanic says his work may have implications for a subset of people who lose their vision. “If intraocular application may be something which would help dogs, that may be a way to go in the humans. And avoid all possible side effects of other types of the therapies which are currently used,” says Grozdanic.
Grozdanic’s collaborator, Randy Kardon, Director of Neuro-Ophthalmology at the University of Iowa, says that in humans, blindness of autoimmune origin is often associated with cancer, a devastating combination for any patient.
“You can just imagine how bad it is for somebody to get diagnosed with cancer and then to go blind, maybe a few months after being diagnosed,” says Grozdanic. “If this approach really continues to work in a safe manner in the dogs, some of these things will easily be applied to humans. At least I believe so. And that can be a huge breakthrough for treatment of humans,” he says.
Roxi has left behind hope that loss of vision may be reversible for some. But that’s not all.
“She brought so much joy to everybody’s life,” says Chelsen, who recalls taking Roxi to visit his mother-in-law at a nursing home. “Everybody would be like, 'Where's Roxi?' It’s not 'Hi Mark' but 'Where's Roxi?'” he says.
He adds, “Life was her party. It was always, 'Thanks for coming.'”
This research by was published in Veterinary Clinics of North America: Small Animal Practice, March 2008, and funded by the Veterans Health Administration and Iowa State University. Sinisa Grozdanic, Matthew Harper, and Helga Kecova are the authors.