This week’s blog on ‘Can astigmatism be cured?’ has been contributed Dr. Osama Giledi, Consultant Ophthalmologist, Specialist in Cataract, Cornea and Refractive Vision Correction Surgery.
What is astigmatism?
Astigmatism is a common kind of refractive error. It is not an eye disease, it means the surface of the cornea is not spherical, or not completely round “the eye is shaped like a Rugby ball, not a football ball.” With astigmatism, the eye does not focus light evenly onto the retina causing blurring of the image formed at the back of the eye.
Causes of astigmatism?
The specific cause is normally unknown although genetics can play a part. Sometimes astigmatism can develop after an eye injury, surgery or because of an eye disease Astigmatism is not caused by reading in bad light, using a PC or watching a lot of TV.
Astigmatism can affect both children and adults, it is usually non progressive and associated with myopia or hyperopia. If the astigmatism is getting worse, then it is very important to see a corneal specialist to a have corneal scan in order to rule out the weaker cornea (Keratoconus) as it is a progressive disease and there is treatment to stop it, especially if detected early, to save the vision.
What are symptoms of astigmatism?
Patients with astigmatism notice a blurred/distorted vision especially at night driving or have frequent headaches, increased eye fatigue, eye strain and squinting.
How is astigmatism diagnosed?
Astigmatism is usually found during eye glasses examination. Most of astigmatism are regular, however some astigmatism are irregular and caused by diseases affecting the cornea such as Keratoconus or corneal scar. Eye examination and a corneal scan is needed to rule out disease causing the astigmatism
Can you have astigmatism and not know it?
It is possible to have mild astigmatism and not know about it. This is especially true for children, who are not aware of their vision being other than normal. Some adults may also have mild astigmatism without any symptoms. Also many people wear glasses for myopia or hypermetropia and have mild astigmatism but were not informed about it.
Treatment: How is astigmatism corrected?
Astigmatism can be rectified with eyeglasses, contact lenses, or surgery.
Multiple ways of correcting astigmatism are:
- Eyeglasses are the simplest and safest way to correct astigmatism.
- Contact Lenses; need special Toric soft contact lens or hard contact lens.
- Refractive Surgery aims to correct astigmatism permanently in association usually with myopia or hypermetropia. There are various types of refractive surgeries to treat astigmatism using:
- Femto LASIK to change the shape of the cornea permanently
- Toric intraocular implant which we use in severe cases who is not suitable for laser vision correction or patient with weak cornea such as Keratoconus eye.
Astigmatism can also be corrected during cataract surgery by using toric intraocular implant so patient does not need to wear glasses after the procedure.
For astigmatism caused by corneal diseases, the treatment can be by different options depending on the disease and level of astigmatism. Options can be surgical cuts in the cornea (now by using femtosecond laser instead of knive), Eximer laser removal of irregular corneal surface and scar, insertion of specific intracorneal rings and lastly by replacing the diseased cornea with corneal graft