Hi all, anyone have a horse with Corpora Nigra cysts? I think her right eye is more affected (see pic). This pic taken outdoor, but covered cross ties. So not quite fully constricted pupil. I have not yet gotten in touch with local Large Animal Opthamologist, and will. Thx.
I’ve had 3, all treated successfully with ablation.
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I groomed for a horse that had significant corpora nigra in both eyes. I believe the owner ended up taking him to the vet hospital and asking them to remove the corpora nigra, though I don’t know what the outcome was.
The horse was refusing with the owner but was fine, even in tight jump-off turns in competition, with both me and trainer (I was put on for a horse show to see if he had any problems with a fellow amateur). Owner continued to insist the horse was blind and took the horse elsewhere and I lost track. I truly believe he could see just fine and that his issues were related to years of rider error (nervous rider pulling and pulling to the jumps in the show ring until the horse had nothing left).
My gelding has one that is quite a lot larger than that. The PPE vet didn’t note it (sight unseen purchase, a bit disappointed in Rood & Riddle for that one. I feel like even if it isn’t an issue it should have at least made it into the notes, especially given the size of this one!) but I noticed it as soon as he got off of the trailer. Due to its size, I had my vet look at it and he thinks that it probably limits his vision somewhat in dark to light type situations but it doesn’t seem to bother him at all so far. He isn’t spookier on that side and doesn’t present like he has any vision issues. He recommended ablation at some point, just due to its size, and it seems to be quite a straightforward procedure. I’m planning on getting it done sometime in the spring.
Here is a thread I started on it that had a couple of responses: Laser removal of cyst in eye - experiences and costs?
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I sold a nice hunter Pony who had unusually large CN in one eye. The vet said it could cause some difficulty in changing focus from dark to light. He’s jumping very well all over the place now, never spooks at anything that can be traced to this condition.
My mare had large cysts in both eyes-- to the point where one completely occluded her vision in any kind of light. It took a long time to diagnose, mostly because I originally had a vet who dismissed my concerns about a vision issue when her behavior became increasingly erratic. She’s since had both cysts ablated and while they’re not completely gone, they’re dramatically reduced. The procedure and healing were easy peasy. Now she’s sort of re-learning how to exist as a horse who can actually see-- she still gets quite nervous in changes of light, or with a lot of commotion happening around her.
My boy has one that was discovered last year. For the time being, I’m not doing anything about. My vet is just monitoring him for now.
My 21 YO gelding has one in both eyes. It was never mentioned to me, and I never noticed it until about 2-3 years ago.
It never effects him except if it is very sunny and bright out and the show has really reflective footing. Then he usually refuses the jumps. He’s too old for a surgical candidate, and really he’s been amazing at his job despite it, so I won’t be removing them. I just scratch when I know it’s going to be too bright for him.
My gelding had a relatively small cyst on his L eye. He was debatably more spooky on the left prior to having laser surgery at OSU, but because this particular horse is quite possibly possessed by a demon, I can’t definitively say so. He didn’t really struggle with light-to-dark and dark-to-light questions. I can’t even tell you how long it was cystic; I never had a PPE done on the horse and I had no idea what a cystic corpora nigra even was or that it was a thing. My veterinary chiropractor just happened to notice it one day, so I called the ophthalmologist to look at it. I opted to have it fixed, mostly for peace of mind and to eliminate any possibility of it affecting him. I think price was maybe $600 or so at OSU? Way cheaper than the laser glaucoma surgeries and cyclosporin implant they did on my other guy since this can be done standing. Recovery was easy-peasy- he came home the same day, had something like 2-3 days off, and was back to showing about 2 weeks later. No further issues with either eye and the referring ophthalmologist was happy with the reduction in size post surgery.
Before surgery:
After surgery:
