A MUM has shared her "heartbreak" after her eight-year-old son was diagnosed with a rare disease that will lead to childhood dementia.
Grayson Naff was diagnosed with Batten disease last year - a fatal condition which causes the brain to gradually shut down over five to ten years.
Emily Blackburn from Tipp City, Ohio, noticed her little boy was standing close to the TV to see it in late August 2022.
So the mum-of-two took him to an ophthalmologist, who noticed an issue in the boy's retina and referred him to a specialist at the Cincinnati Eye Institute.
After genetic testing, Grayson was diagnosed with Batten disease.
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Emily said: "This is what heartbreak is. The pain is beyond words. There are times I have trouble breathing through this nightmare."
She told Fox News he can see about 5 to 10 inches in front of him and is now considered legally blind.
"If there is no approved treatment/cure in the coming years Grayson will lose every function he has now, the first being full blindness," she said.
"Accepting that my son is legally blind — and that if he goes down the typical path of Batten disease, he will likely lose all of his vision — is heartbreaking."
Grayson recently started training with a white cane - a mobility tool for the visually impaired.
Reflecting on her son's journey, Emily said: "No one prepares you for this. I wake up every day and have to remember that this is our life."
Batten disease causes a progressing loss of physical and mental abilities that includes blindness and seizures.
It usually begins in childhood and is an inherited or genetic disease.
There is currently no cure for Batten disease, with life expectancy typically in the mid-teens to early 20s.
Grayson takes Miglustat, a drug which is hoped could ease or slow down symptoms.
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However, the drug is not yet FDA-approved and could cost the family around $100 per pill or $9,000 every month.
