Understanding your eyes helps you take better care of them. Here is what you need to know about eye anatomy, examinations and common conditions.
Eye Anatomy
← Hover over any part of the diagram
✓Cornea—the clear, transparent front layer of the eye through which light passes.
✓Iris and Pupil—the iris gives the eye its colour and controls how much light enters, like a camera aperture. The pupil is the dark opening at its centre.
✓Lens—helps to focus light on the retina.
✓Retina—the innermost layer at the back of the eye. The macula is the central zone providing our most acute vision.
✓Optic Nerve—conducts visual impulses from the retina to the brain.
Eye Examination
A general eye examination is more than just getting your eyes checked for a lens prescription — it involves several tests to check your vision and screen for eye disease.
We recommend a comprehensive eye examination every year. Regular annual check-ups allow early detection of conditions such as glaucoma, macular degeneration, and diabetic eye disease — many of which have no symptoms in their early stages.
Tests Performed During an Eye Examination
✓Visual acuity test—checks how well you see from a distance of about 20 feet using a Snellen chart.
✓Eye muscle test—checks the muscles that control eye movement.
✓Refraction test—determines whether corrective lenses are needed and the precise prescription required.
✓Visual field test—measures peripheral (side) vision using automated perimetry or confrontation testing.
✓Colour vision test—detects colour deficiencies using multicoloured dot patterns.
✓Slit lamp examination—magnifies the cornea, lens, iris and anterior chamber to detect abnormalities.
✓Retinal examination—examines the retina and optic nerve, usually after pupil dilation.
✓Glaucoma test (tonometry)—measures internal eye pressure using noncontact, applanation, or pachymetry methods.
