Myopia (short sightedness) is when you have trouble seeing in the distance. There is currently no cure for myopia, however spectacles, contact lenses, orthokeratology and refractive surgery can all provide good distance vision for people with myopia.
Hyperopia (long sightedness) is when you have trouble seeing up close. People with hyperopia often have reasonable vision in the distance, but may find that their vision is blurred or that they experience feelings of eyestrain or headaches when doing near work such as reading. Hyperopia can be managed through spectacles and some eye exercises. Your optometrist can advise you of the recommended course of management
Presbopia is a common condition that makes reading difficult with age, caused by the gradual reduction in the amount that the eye can change its focus. The changes are the result of the continued growth of the biological lens inside the eye, and are a normal part of ageing. Presbyopia usually becomes noticeable between the ages of 40 and 50 as an inability to focus on near objects. People in this age group often find that they have to hold things further away to see them clearly. Presbyopia can be corrected by an optical prescription specifically designed for close work. This can be provided in many forms, including reading glasses, bifocals, trifocals and progressive lenses (multifocals).
Astigmatism is when the front of the the eye is oval shaped and means blurred vision at all distances. Astigmatism is a focusing error which causes asymmetric blur. Some directions in an image are more out of focus than others. This can be contrasted with short-sightedness (myopia) where all directions are uniformly blurred.
Spectacles and contact lenses (hard and soft) can correct astigmatism. Sometimes correction of astigmatism can cause change in the apparent size and shape of objects and may affect judgement of distance. A patient may feel taller or shorter, or walls may appear to slope and floors curve.
In most cases, adjustment to these side effects takes only a week or so. Astigmatism correction may involve a compromise between optimal clarity and visual discomfort.
Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. This condition is also sometimes called lazy eye. A common cause of amblyopia is the inability of one eye to focus as well as the other one. Amblyopia can occur when one eye is more nearsighted, more farsighted, or has more astigmatism. Treating amblyopia involves forcing the child to use the eye with weaker vision. Amblyopia can be treated by patching or by using drops. Your optometrist will be able to advise on the best form of treatment.
Strabismus is a failure of the two eyes to maintain proper alignment and work together as a team. With strabismus, one eye looks directly at the object you are viewing, while the other eye is misaligned inward (esotropia, "crossed eyes" or "cross-eyed"), outward (exotropia or "wall-eyed"), upward (hypertropia) or downward (hypotropia).
Treatment for Strabismus can include vision therapy, exercises or in most circumstances surgical correction. The earlier strabismus is treated surgically, the more likely it is that the affected eye will develop normal visual acuity and the two eyes will function together properly as a team.