When performing an eye examination, the nurse should use an ophthalmoscope to best visualize the fundus, which is the inner lining of the eye. The fundus includes the optic nerve, the macula, and the blood vessels. An ophthalmoscope is an instrument that can be used to inspect the fundus of the eye, and it is typically used to check for signs of eye diseases, such as glaucoma, macular degeneration, and diabetic retinopathy.