Astigmatism and your treatment options
Escrito por:Astigmatism affects the shape of your eye and causes your vision to become blurry. There are ways to correct this, however, and in this article ophthalmologist Mr Aris Konstantopoulos clarifies the diagnosis and treatment of astigmatism, along with the safety of the procedures.
What is astigmatism?
Astigmatism is a common eye condition that is usually caused by a non-uniform shape to the cornea or the development of abnormalities in the natural lens inside your eye.
Normally, the combined refractive efforts of the cornea and your natural lens focus light rays sharply on the retina of the eye. Whereas in astigmatism, the imperfect refractive capabilities of the eye result in an object not being fully focused on by your retina. If short-sightedness (myopia) or long-sightedness (hypermetropia) are also present, the object may be focused in front of or behind the retina, resulting in blurred vision.
How is astigmatism diagnosed?
Astigmatism is usually diagnosed by your optician. It predominantly causes blurred vision but in early or mild cases, it may cause headaches, eyestrain, and difficulty with night driving. A variety of eye conditions can cause these symptoms; the only true way of knowing if you have astigmatism, or other refractive errors such as short-sightedness or long-sightedness, is with a thorough eye examination.
Can astigmatism get worse without treatment?
Astigmatism will not go away without treatment. It is often said that astigmatism does not change with age, but in reality, there is a very small change in the shape of the cornea and thus astigmatism with time.
A rapid increase in myopia and astigmatism can be a sign of keratoconus, a progressive condition in which the cornea becomes weaker and bulges forward; this requires further investigations. These investigations are usually carried out by an ophthalmologist (a doctor that specialises in eye care) who will carry out a detailed examination and corneal topography imaging. A corneal topography involves detailed scanning of the cornea, plotting its shape and comparing it to expectations for eyes without astigmatism.
What ways can astigmatism be treated?
Treatment options for astigmatism include glasses, contact lenses and refractive eye surgery.
The vast majority of patients with astigmatism use glasses to see better. With moderate to high prescriptions, however, glasses can be difficult to adjust to and may reduce the quality of vision with peripheral distortion.
A more permanent solution to astigmatism can be provided by refractive surgery. Depending on your prescription, eye measurements and visual needs, a variety of procedures are available, including LASIK, SMILE, toric phakic IOL, e.g. ICL, and refractive lens exchange.
In LASIK, an excimer laser sculpts the cornea to correct its surface and refractive power, therefore correcting astigmatism. If you have astigmatism and also wear reading glasses, LASIK can incorporate a PRESBYOND blended vision treatment to reduce or eliminate your need for reading glasses.
SMILE is a keyhole alternative to LASIK that uses a femtosecond laser to reshape the cornea and there is no need to cut a flap in the eye in this procedure. This preserves the biomechanical stability of the cornea better and allows a more rapid return to intense physical activities and swimming than with LASIK.
A toric ICL is like a permanent plastic contact lens that is implanted inside your eye, in front of your natural lens. No one can see this phakic lens and you cannot feel its presence in your eye. This is a safe alternative to LASIK and SMILE, but it is usually reserved for higher prescriptions when laser vision correction may not be the best option.
In refractive lens exchange, your natural lens is replaced with an artificial lens, very similar to modern cataract surgery. This treatment option for astigmatism is most appropriate if you are over the age of 55 or if your prescription is higher than the normal range for laser vision correction.
Can contact lenses help with astigmatism?
Specialised soft toric and rigid gas permeable contact lenses can be used to treat astigmatism as the contact lens compensates for the difference in refractive power across the cornea. Contact lenses also correct co-existing long-sightedness or short-sightedness at the same time.
How safe is laser vision correction for astigmatism?
Laser vision correction is the most common elective procedure carried out worldwide; over 100,000 procedures are performed each year in the UK.
Laser vision correction is carried out on the surface of or within the cornea, i.e. not inside the eye. As a result, it’s a smaller operation for your eye and the chances of going blind following laser treatment are minuscule. More than 99% of patients achieve driving level vision without glasses or contact lenses. Indeed, laser treatment is as safe if not safer than long-term contact lens wear!
On the website for my centre Aris Vision Correction, you can learn even more about LASIK, SMILE, PRESBYOND and refractive lens exchange.
If you suffer from short-sightedness (myopia), long-sightedness (hypermetropia), astigmatism or need reading glasses, book an appointment via Mr Konstantopoulos’ Top Doctors profile.