Understanding Visual Acuity and Correction Options

Normally, vision is caused by light hitting the surface of the cornea. then refraction occurs focusing on the retina The image that can be seen is therefore clear. whether the object is near or far But if the curvature of the cornea or the length of the eyeball too much or too little will cause the image to be seen unclearly, which is called visual acuity

There are four types of visual acuity.

1. Nearsightedness (Myopia)

Caused by the focus of light on the retina. Often caused by eyeballs that are too long. or caused by excessive curvature of the cornea Those who are short-sighted can see at close range. but will not see clearly from a distance

Risk factors that cause nearsightedness, such as genetics from parents who are nearsighted. or have the behavior of using eyesight in the near term too much Whether reading a book use computer and mobile phone

2. Farsightedness (Hyperopia)

It is caused by the eye’s focus of light falling behind or beyond the retina. It is usually caused by the eyeball being too short or the cornea curvature being too small. People with farsightedness therefore cannot see clearly either near or far. Farsightedness is not the same type as long-sightedness in the elderly.

3. Astigmatism

Caused by the curvature of the cornea in each direction is not equal. Causing the light to focus on the retina is not a single point therefore seen as a double image May occur with nearsightedness or farsightedness.

However, most people are born with mild astigmatism. and may occur in conjunction with nearsightedness and farsightedness For people with severe astigmatism, symptoms such as blurred or distorted vision, headache, eye pain, eye strain, and diffuse light are seen. And have to try to squint all the time to adjust the focus to see more clearly

Long-sightedness in the elderly (Presbyopia)

It is a condition caused by the deterioration of the muscles in the eye used to adjust near-far vision. and caused by hardening of the intraocular lens, which is less flexible blurs close vision In which long-sightedness in the elderly will begin to show symptoms in people aged 40 years and over.

correction of visual acuity

1. Correction without surgery

• Eyeglasses (Spectacles) Lenses of eyeglasses will help to concentrate light onto the screen. which is safe easy to maintain But there are some limitations, such as being inconvenient to do outdoor activities or working in some occupations such as athletes, soldiers, pilots, etc.
• Contact Lenses are another option for people with impaired vision. and inconvenient to wear glasses or athletes who have to move all the time It can solve the problem of short-sightedness, long-sightedness, and astigmatism, helping to see a wide-angle view well. and suitable for those who have very different eyesight But there will be precautions in maintaining cleanliness. because there is a risk of corneal infection which can be so severe as to lose an eye and those who are not suitable for using contact lenses, such as dry eye conditions, allergies, protein deposits that accumulate in the lenses and in lens cleaning solution Wearing contact lenses is not recommended. While doing some activities such as swimming, diving and should not be worn while sleeping. The use of contact lenses should be examined and recommended by an ophthalmologist.

2. Correction by surgery

• Surgery with PRK (photorefractive keratectomy) by removing the surface of the chest tissue. By peeling off the outer layer of the cornea and then using a cold excimer laser (excimer laser) to shoot down the cornea below to adjust the curvature of the cornea and correct abnormal vision before closing the cornea. with prescription contact lenses
• Lasik surgery (LASIK) is an eye surgery that involves opening a hinged flap of the cornea with a blade or femtosecond laser and using an excimer laser to adjust the curvature of the cornea.
• ReLEx SMILE Pro is a treatment for nearsightedness and astigmatism by correcting the corneal curvature using a femtosecond laser that splits corneal tissue into lens shapes. The lenticule is then removed through a small incision, 2-4 mm.

Information from: Dr. Bundita Lertsuwanroj, M.D.

For more information, please click!! Eye Center, 4th floor, Zone A

Normally, vision is caused by light hitting the surface of the cornea. then refraction occurs focusing on the retina The image that can be seen is therefore clear. whether the object is near or far But if the curvature of the cornea or the length of the eyeball too much or too little will cause the image to be seen unclearly, which is called visual acuity

There are four types of visual acuity.

1. Nearsightedness (Myopia)

Caused by the focus of light on the retina. Often caused by eyeballs that are too long. or caused by excessive curvature of the cornea Those who are short-sighted can see at close range. but will not see clearly from a distance

Risk factors that cause nearsightedness, such as genetics from parents who are nearsighted. or have the behavior of using eyesight in the near term too much Whether reading a book use computer and mobile phone

2. Farsightedness (Hyperopia)

It is caused by the eye’s focus of light falling behind or beyond the retina. It is usually caused by the eyeball being too short or the cornea curvature being too small. People with farsightedness therefore cannot see clearly either near or far. Farsightedness is not the same type as long-sightedness in the elderly.

3. Astigmatism

Caused by the curvature of the cornea in each direction is not equal. Causing the light to focus on the retina is not a single point therefore seen as a double image May occur with nearsightedness or farsightedness.

However, most people are born with mild astigmatism. and may occur in conjunction with nearsightedness and farsightedness For people with severe astigmatism, symptoms such as blurred or distorted vision, headache, eye pain, eye strain, and diffuse light are seen. And have to try to squint all the time to adjust the focus to see more clearly

Long-sightedness in the elderly (Presbyopia)

It is a condition caused by the deterioration of the muscles in the eye used to adjust near-far vision. and caused by hardening of the intraocular lens, which is less flexible blurs close vision In which long-sightedness in the elderly will begin to show symptoms in people aged 40 years and over.

correction of visual acuity

1. Correction without surgery

• Eyeglasses (Spectacles) Lenses of eyeglasses will help to concentrate light onto the screen. which is safe easy to maintain But there are some limitations, such as being inconvenient to do outdoor activities or working in some occupations such as athletes, soldiers, pilots, etc.
• Contact Lenses are another option for people with impaired vision. and inconvenient to wear glasses or athletes who have to move all the time It can solve the problem of short-sightedness, long-sightedness, and astigmatism, helping to see a wide-angle view well. and suitable for those who have very different eyesight But there will be precautions in maintaining cleanliness. because there is a risk of corneal infection which can be so severe as to lose an eye And those who are not suitable for using contact lenses, such as dry eye conditions, allergies, protein stains that accumulate in the lens and in lens cleaning solution Wearing contact lenses is not recommended. While doing some activities such as swimming, diving and should not be worn while sleeping. The use of contact lenses should be examined and recommended by an ophthalmologist.

2. Correction by surgery

• Surgery with PRK (photorefractive keratectomy) by removing the surface of the chest tissue. By peeling off the outer layer of the cornea and then using a cold excimer laser (excimer laser) to shoot down the cornea below to adjust the curvature of the cornea and correct abnormal vision before closing the cornea. with prescription contact lenses
• Lasik surgery (LASIK) is an eye surgery that involves opening a hinged flap of the cornea with a blade or femtosecond laser and using an excimer laser to adjust the curvature of the cornea.
• ReLEx SMILE Pro is a treatment for nearsightedness and astigmatism by correcting the corneal curvature using a femtosecond laser that splits corneal tissue into lens shapes. The lenticule is then removed through a small incision, 2-4 mm.

Information from: Dr. Bundita Lertsuwanroj, M.D.

For more information, please click!! Eye Center, 4th floor, Zone A