Astigmatism:Causes,Symptoms,Types & Treatment
Astigmatism: Astigmatism is a common vision condition that makes the blurred vision. Astigmatism happens when either the front surface of the eye (cornea) or the lens, inside your eye, has mismatched curves. Alternately of having one curve like a round ball, the surface is egg shaped. This causes blurred vision at all distances. Astigmatism ordinarily occurs with other vision conditions like myopia and hyperopia. The distinct cause of astigmatism is unknown. It can be hereditary and is normally present from birth. It can increase or decrease over time. When it is, your treatment options are corrective lenses or surgery.
Causes of Astigmatism
Astigmatism ordinarily is generated by an irregularly shaped of the cornea. In some circumstances, astigmatism is precipitated by the shape of the lens inside the eye. This is called lenticular astigmatism, to differentiate it from the more common corneal astigmatism. In addition, the shape of the lens inside the eye can change, follow in an increase or decrease in astigmatism. Astigmatism also happens due to a comparatively rare condition called keratoconus in which the cornea becomes progressively thinner and cone-shaped. Sometimes astigmatism may happen following an eye trauma or eye surgery. There’s a myth that you can get it if you read in low light or sit too close to the TV, but that isn’t true.
Types of Astigmatism
There are three primary types of astigmatism:
- Myopic Astigmatism. It means that either one or both of the principal meridians are nearsighted. If only one meridian is nearsighted, that is simple myopic astigmatism. If both are nearsighted, that is compound myopic astigmatism.7
- Hyperopic Astigmatism. One or both of the principal meridians are farsighted. If only one of the meridians is farsighted, that is simple hyperopic astigmatism. If both are affected, that is compound hyperopic astigmatism.
- Mixed astigmatism. This type of astigmatism means that one of the meridians is nearsighted, while the other is farsighted.
Irregular astigmatism can happen when an eye injury that scarring on the cornea, or from keratoconus, a disease that creates a gradual thinning of the cornea.
Symptoms of Astigmatism
Astigmatism usually produces blurred vision or distorted to some degree at all ranges.Symptoms of uncorrected astigmatism are eye strain and headaches, particularly after reading or other lengthy visual tasks.Squinting also a common symptom.
Diagnosis of Astigmatism
Treatment of Astigmatism
People with astigmatism have numerous options to recover clear vision. This may include:
- Eyeglasses- People with astigmatism primarily choose eyeglasses to improve their vision.
- Contact lenses-Some people will have better vision with contact lenses rather than eyeglasses.
- Orthokeratology-A set of rigid contact lenses to reshape the cornea. The patient uses contact lenses for limited times, such as overnight, and then removes them. People with moderate astigmatism may be capable to temporarily obtain clear vision without lenses for the maximum of their daily activities. Orthokeratology does not permanently correct vision. If patients stop using the retainer lenses, their vision may turn to its original condition.
- LASER-Astigmatism can also be corrected by reshaping the cornea through LASIK. LASIK removes tissue only from the inner layer of the cornea.