The methods used to look at the back of the eye (the fundus), including the optic disc, retina and vessels.
Ophthalmoscopy views the fundus: direct gives a high-magnification, small, upright view (good for the disc); indirect gives a wide, less magnified, inverted view (good for the periphery); dilate the pupil to see more.
Cataract
Clouding of the lens causing painless, progressive loss of vision.
Glaucoma
Optic-nerve damage, usually linked to raised intraocular pressure.
Diabetic Retinopathy
Microvascular damage to the retina from long-standing diabetes.
Conjunctivitis
Inflammation of the conjunctiva — the common 'red eye'.
Refractive Errors
The eye fails to focus light sharply on the retina.
Retinal Detachment
Separation of the retina from the underlying layer — an eye emergency.