How often should I check my eyesight if I have floaters and high myopia?

Your eyesight (visual acuity) is not usually the issue in the situation you describe. But you are wise to pay attention and seek an ophthalmologist's assessment. High myopia is associated with a greater than normal incidence of retinal problems, even retinal detachment, which can be quite serious. If there is a fairly recent onset of seeing "floaters" or specks in your field of vision (especially if accompanied by flashes of light off to the side), you should see an ophthalmologist rather soon.

Once the degree of problem (if any) has been assessed, you will be educated as to the other onset signs of retinal problems. Once a year then would be fine for most people without retinal issues, more frequently if a hole or tear in the retina is identified.

Here's more information on floaters

Here's more information about myopia (nearsightedness)

Written by J.Trevor Woodhams, M.D. - Chief of Surgery, Woodhams Eye Clinic