Karev (Justin Chambers) examines Meredith's (Ellen Pompeo) eyes with a slit-lamp biomicroscope. However, he never turns the lamp on. He just looks through the eyepieces with no light. Although he admits "I'm not an eye guy; I don't know how to use this stuff", he then tells Meredith "your corneas look fine". Without the lamp on, he couldn't have seen anything.
Hunt is playing golf at the roof of the hospital at the end of this episode. However, in season 12, he says that he doesn't like golf.