Page Fuller has revealed she suffered a mini-stroke during a race at Fontwell last week, which left her blind in one eye when jumping a fence.
The jockey pulled her horse Touchthesoul up early at the Sussex track on Friday after jumping just one obstacle, with the 27-year-old struggling to see out of her right eye.
An MRI scan in hospital revealed a tear in the arteries in her neck, caused by a fall at Plumpton last month, had led to a blood clot.
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Reflecting on the incident at Fontwell, Fuller told the Racing Post: "I jumped off feeling absolutely fine, but then felt a bit funny and couldn't really see anything on my right side.
"I was down the inside and couldn't see any of the horses to my right. I looked round and could see them with my left eye, but not my right eye.
"Coming into the fence, my vision went right down and I could only just see it, but, luckily, the horse was a bit of a life-saver and got me over. When I went to pull him up, I realised my right arm was weak and in spasm with pins and needles."
Providing an update on her condition on Tuesday, Fuller tweeted: "Thank you so much to everyone for all the love and support over the weekend, all your messages have been so greatly appreciated.
"I'm feeling good and the doctors are very happy with me so sent me home last night. I'm now looking forward to cracking on with my rehab at OakseyHouse."
Fuller admits she does not know what the future holds long-term, with her riding career in doubt.
"At the end of the day getting my health right is the priority now," Fuller said. "Things will depend on how the artery heals.
"It's going to be a long process, but I'm going to have the right people around me with Oaksey House. I feel confident I haven't had any significant effects in terms of dexterity, so hopefully I can get back to normal, but you can never take that for granted.
"When you say stroke, it sounds awful because strokes can be awful, but I'm hoping - the way everyone is talking about - I'm at the less-severe end of what it could have been."