OK lenses, i.e. Keratoplasty lenses, may cause blurring of vision on the next day, deterioration of visual quality and loss of wearing comfort if worn in the opposite direction in the left and right eyes. Since keratoplasty lenses are rigid contact lenses, it is easier to distinguish between front and back based on the concave and convex surfaces, but it is possible to wear the lenses on the opposite side of the eye. Due to the difference in degree between the two eyes and the degree of curvature at the time of design, it may firstly lead to poor corrective effect, blurred vision on the next day, and decreased comfort when using the lenses. In serious cases, due to the cuts of the peripheral lenses, the friction of the cornea causes corneal surface stinging, redness, tears, and even damage to the cornea, resulting in corneal infections, ulcers and other conditions, when the decline in comfort and corneal stinging and other conditions need to be removed in time for examination, if not caused by the left and right eyes wear the opposite need to go to the dispensing office or ophthalmology department for examination.