Of course I cannot make a diagnosis but the most common cause would be eye muscle problem, your mother having the problem (which occurs in 2% of the population) increases the risk of any blood relative of hers (you, your siblings, your and their children) to 20%. While most eye muscle problems start at birth on in early childhood some can occur in adults.
Being a runner I'm hoping she does not smoke. Smoking is very bad but smoking with migraines dramatically increases the risk of strokes.
This does call for evaluation by an ophthalmologist and her personal physician. If this continues or something else develops she likely will need to see a neurologist.
This is not likely related to glaucoma or glaucoma medications.
JCH MD
She is 22 and has optical migraines
She reports loosing stamina lately when she runs
My mom had strabismus she called it crossed eyes she was born with
She and I have glaucoma .
Thanks
What is your child's age? Does her health otherwise seem excellent? When her eye gets stuck does her behavior change? like in a trance? any movement of her extremeties (like petite mal seizure). Any family history of eye muscle problems (strabismus)?
JCH MD