Seeing an opthamologist (physician for vision, diseases of the eye, and surgery) and not an optometrist (vision only) to check your vision and the optic nerves is an excellent idea. Does the GP know about the eye issue too? If not, make sure he/she knows about ALL of your symptoms: with tingling in your arm, blurred vision, and stenosis of cervical vertebrae. See also what the opthamologist says and go from there. Best wishes.