Visual disturbances when the eyes are healthy, what are some causes?

Need more info. What type of visual disturbance are you having?
Mostly refractive. If your eyes are truly healthy then the most likely visual disturbance by far is a need for eyeglasses. Vision can be disturbed by vascular insult, contact lense problems and hereditary problems. Have your ophthalmologist give you the glasses you need. Congratulations on healthy eyes.