Optometry: sight tests, contact lenses, eye health checks and when to be referred

Optometry is the primary eye care profession. Optometrists examine the eyes, test how well you see, prescribe glasses and contact lenses, check eye health and refer people with disease to the right service. They are trained at degree level and the College of Optometrists describes a route in which a GOC-approved degree is followed by a supervised scheme for registration before someone can qualify as an optometrist.

Dispensing opticians are a separate registered group who fit and supply glasses and, in some cases, contact lenses. Many high street practices combine both roles. The General Optical Council regulates both groups, protects the public and publishes a searchable register so you can check that a practitioner is registered.

Optometry is not the same as ophthalmology. An optometrist works mostly in community practice and screens, monitors and co-manages. An ophthalmologist is a medical doctor who treats eye disease and operates. Some optometrists work in hospital eye clinics, and some hold extra qualifications such as independent prescribing, so a hospital team may share long-term monitoring with them.

A sight test is both a prescription check and a health check. The NHS says that for short-sightedness the optometrist will usually ask you to read letters from a chart while different lenses are placed in front of your eyes, and may give drops to widen the pupil so the back of the eye can be seen more clearly.

• A conversation about your symptoms, family eye history, general health, medicines, work and screen use.

• Measuring how well each eye sees, with and without glasses, and working out the prescription.

• Checking how the eyes work together, including eye movement and focusing.

• Measuring pressure inside the eye and mapping the visual field where indicated.

• Looking at the front and back of the eye, often with retinal photography or optical coherence tomography.

• Explaining the findings and giving a written prescription that you can take to any optician.

Refractive error, meaning short-sightedness, long-sightedness, astigmatism and the focusing change in the 40s called presbyopia, is the largest part of the work. Short-sightedness can usually be corrected with glasses or contact lenses, and the NHS adds that laser or lens surgery for it is not available on the NHS.

Dry eye and blepharitis are everyday complaints. The NHS describes cleaning the eyelids, taking screen breaks and using a humidifier as self-care, and advises seeing an optician or GP if dry eyes persist after a few weeks of home treatment. For blepharitis it suggests cleaning the eyelids twice a day and avoiding contact lenses and eye make-up while symptoms last.

Optometrists also notice early signs of cataracts, glaucoma, age-related macular degeneration and diabetic retinopathy, and arrange referral. In some areas they run minor eye conditions services and glaucoma monitoring on behalf of the NHS.

The NHS lists people entitled to a free sight test, including those under 16, those aged 16 to 18 in full-time education, people aged 60 or over, people with diabetes or glaucoma, people aged 40 or over whose parent, sibling or child has glaucoma, and some people on certain benefits. Optical vouchers help towards the cost of glasses or contact lenses for specific groups, and a mobile sight test can be arranged for those unable to leave home unaccompanied.

People outside those groups pay for the test and any glasses. Prices differ between practices and depend on lens type, coatings and frames, so ask for a written breakdown. Contact lens wearers usually pay a regular fee that covers aftercare appointments. Specialist tests such as extra imaging, dry eye assessments and myopia management programmes may be priced separately.

If the optometrist finds something that needs a medical opinion they refer you to your GP or direct to the hospital eye service, and urgent findings may be sent the same day. You can ask for a copy of the findings and referral letter.

• Bring all your current glasses, contact lenses or lens boxes and a list of medicines, particularly steroids or medicines for diabetes and blood pressure.

• Tell the optometrist about family history of glaucoma, macular degeneration or early cataract, since this affects how often you are re-tested.

• Ask how often you should be tested, what any imaging showed and whether anything needs monitoring.

• If you wear contact lenses, ask about cleaning, wearing time and what to do if an eye becomes red or sore.

• See an optician or GP for dry eyes that persist after a few weeks of home care.

• Get urgent help from NHS 111 or an urgent GP appointment for a painful red eye, especially if you wear contact lenses. Call 999 or go to A&E for sudden loss of vision, flashing lights or wavy lines, severe pain with headache and nausea, or an eye injury, as the NHS advises.