Astigmatism is a common eye problem that can make your vision blurry or distorted but is easily treated
Astigmatism is a type of refractive error caused by the irregular shape of the cornea or the lens inside the eye. Corneal astigmatism happens when there’s a defect or distortion in the cornea. Lenticular astigmatism occurs when there’s a distortion in the lens.
Optometrist Anna Bong explained: “In layman’s terms, the normal and perfect eyeball would be in the shape of a football. Astigmatism is when the eyeball changes into the shape of a rugby ball, which cannot focus light directly onto the retina and instead, the light is scattered at certain angles.”
Anna, who runs her optometry practice Anna Eyecare Optometry in Kuching, said just like the human body, the shape of the cornea and lens varies from person to person. Therefore, most people tend to have mild or slight astigmatism as their eyeball shape is not perfectly round since birth.
Severe cases of high astigmatism are usually inherited genetically. People can also get astigmatism due to excessive eye rubbing at a young age when the eye is still developing and moulding its shape, eye diseases, eye injury or after surgery.
Astigmatism is measured in diopters, the optical power of a lens. You are said to have astigmatism when the diopter reading is above 0.5, which is the measurement for slight astigmatism. It usually does not necessitate treatment or corrective lenses. Only those with a diopter measurement of one or higher will require contacts or lenses.
Optical prescription for astigmatism corrective lenses or contacts uses cylinder and axis measurement. The cylinder part of the prescription measures the diopter, the degree or extent of the irregularity. Meanwhile, axis measurements are used to determine the location of eye astigmatism on the cornea.
Debunking misconception about astigmatism
The awareness of astigmatism is relatively low, and many misconceptions surround it.
Astigmatism is commonly thought only to affect adults. This is untrue because most cases of astigmatism are inherited. Usually, children are unaware that their vision is distorted. Therefore, children need to have regular eye examinations.
Another misconception is astigmatism is caused or worsened by reading in low light and increased screen time. While these activities are not recommended to prevent eye strain, it does not affect astigmatism specifically.
“Screen time does not affect astigmatism. It is mainly related to distance. Continuous near work or leaning closely towards a digital screen, especially for children, will elongate and change the shape of the eye, leading to myopia and astigmatism.
“Another critical misconception is that most people believe they cannot wear contact lenses if they have astigmatism. This is untrue. As long the astigmatism is not too severe, it is possible to wear a contact lens to correct your astigmatism.
“Soft lenses can be used for those with astigmatism up to -2.75 diopter. Meanwhile, rigid lenses can be used by those with measurement up to -4 diopter.”
Managing patients with astigmatism
“We cannot cure astigmatism because it is not a disease. It is a refractive error; therefore, the vision can be corrected with the help of glasses or contact lenses. And we must monitor it regularly to prevent it from worsening quickly,” explained Anna.
She shared her experience managing a patient with astigmatism. “I had a patient who came to make new glasses because her night vision was poor. Examination showed that she had astigmatism at about 2.5 diopters.
“As an astigmatism sufferer myself, I know the importance of measuring the axis of astigmatism. If the axis reading is slightly off, the vision will still be blurry. So, after a proper examination, I got the accurate axis measurement and prescribed suitable contact lens for her.
“With the ACUVUE Vita contact lenses for astigmatism, her night vision improved. She is now a loyal customer of Anna Eyecare Optometry and ACUVUE Vita contact lens.”
On her partnership with ACUVUE, she said it had always supported her practice and service with its wide range of products and trial lenses.
“With ACUVUE products, I’m able to provide the best eyecare services to my customers and prescribe lenses accordingly to their lifestyle and eye and vision power and condition.” – The Health