Monovision LASIK for Presbyopia
Presbyopia, commonly known as “Lao Hua”, is a condition where the eye loses the ability to accommodate and focus at near objects. This occurs as part of the normal aging process which usually presents from the age of 40 onwards. It is a result of an age-related decrease in the elasticity of the eye lens and weakening of the accommodation muscles. People with presbyopia tend to hold near objects further away in order to see better. Their difficulty in seeing near objects becomes worse in dim lighting conditions. However, their distance vision is not affected.
Monovision LASIK presents an option for patients who wish to overcome presbyopia to reduce their dependency on reading glasses. In a monovision LASIK procedure, the dominant eye is usually fully corrected for distance vision, while the less dominant eye will be intentionally over or under corrected for near vision, leaving it mildly near-sighted. The mild near-sightedness of one eye will allow the patient to see near objects clearly even without glasses.
After monovision LASIK surgery, the dominant eye will be responsible for providing clear distance vision while the non-dominant eye will provide clear near vision. With time, your brain will slowly adjust and adapt to the monovision treatment, and automatically obtains the best image of what you see. At various distances, your brain will signal the appropriate guiding eye to lead to see. The adjustment period usually takes a few days to a few weeks.
It may take up to a few weeks for some people to adapt after monovision LASIK. The vision may appear slightly less sharp at the beginning as the brain learns to adjust. For most individuals who have undergone monovision LASIK, the convenience of being able to see reasonably well at both near and far distances without glasses can make up for the minor loss of clarity in distance vision.
PRESBYOND® Laser Blended Vision Technology
PRESBYOND® is a type of monovision LASIK that uses a customized corneal refractive treatment software to correct the dominant eye for distance vision and the less dominant eye for near vision, with an overlap in the middle. This overlap provides a unique blend zone which contributes to intermediate vision. After the treatment, the two eyes relay information to the brain for distance, intermediate, and near vision and this allows the patient to see the range of distances without glasses. This advanced laser blended vision technology results in about 97% of patients having good vision outcome after refractive surgery.
Benefits of PRESBYOND®
- Good vision outcomes for all distances ie. near, far, and intermediate.
- Provides a unique blend zone which results in good intermediate vision.
- Most patients can read the very same day of the procedure, often when still on the patient bed.
- No loss of contrast sensitivity since there are no multiple images on one retina.
- No loss of stereo acuity due to good image fusion.
ZEISS CRS-Master® software – A customized treatment planning software
Is Monovision LASIK for me?
Undergoing monovision LASIK is a choice which may be dependent on one’s lifestyle choices. You may consider the following points to help you decide if monovision LASIK is the right choice for you.
- The amount of time spent on activities that require close vision vs distance vision. For example, your work tasks, hobbies, as well as daily activities like applying makeup, shaving, working outdoors, driving, reading, etc.
- Your work environment, for example an office setting in which you spend long hours doing computer work.
- Your ability to adjust to vision changes in each eye.
- Your willingness to compromise a small amount of distance vision in exchange for good near vision.
Experiencing Monovision LASIK
It is important to understand the concept of monovision before proceeding with the treatment as not all patients can adapt to monovision correction. During the eye assessment, our optometrist will prepare the appropriate trial lenses for you to try on. This will provide an actual simulation of the possible monovision outcome. Our eye doctors will also be able to answer any of your concerns and queries regarding the suitability of monovision refractive surgery before you choose whether or not to proceed with monovision correction.
If you require more time to consider before making a decision, you may also try on monovision contact lens during your daily activities and decide if you are comfortable with the possible monovision outcome.