Why is an eyeglass prescription not a contact lens prescription?

The doctors in our office are frequently asked to give a "contact lens prescription" after doing an eye examination for glasses or even after placing a "trial" contact lens on a prospective contact lens wearer's eye. When the patient's request is refused, they understandably become upset. During the routine examination, doctors perform certain tests which give more information about what contact lens might be worn. Additional things to be considered are: 1: History - occupation, age and prior contact lens history. 2: General Health of the patient 3: Health of the patient's eye- the tear composition, the corneal integrity, etc. 4: Curvature of the cornea - amount and degree of corneal astigmatism. If the doctor feels that the patient is a good candidate for contact lenses, a "trial lens" must be placed on the eye. EVERY LENS IS A "TRIAL LENS" UNTIL AFTER SEVERAL WEEKS (OR LONGER) OF WEAR AND THE DOCTOR AND PATIENT ARE SATISFIED ABOUT THE LENSES SUITABILITY. A lens that looks ...  more