Experiencing unsharp vision, blurry or double images, and difficulty seeing details? These symptoms, often accompanied by headaches and eye strain, may indicate refractive errors such as nearsightedness, astigmatism, or farsightedness. These common eye conditions can be effectively addressed through glasses or contact lenses.

However, there are limitations when the vision in both eyes is unequal, or if one eye has significantly different refractive needs. Wearing thick, heavy glasses can create pressure on the nose, squeeze the temples, and lead to headaches, dizziness, and eye discomfort. Additionally, glasses can cause image distortion and out-of-focus vision, impacting daily activities like driving and navigating stairs.

Wearing contact lenses is another option that can alleviate some issues associated with glasses. However, maintaining strict hygiene is crucial, especially in environments with PM2.5 dust, which can cause dry, irritated eyes. Without proper care, contact lenses can lead to infections, and prolonged use can increase the risk of inflammation, potentially resulting in vision loss.

Therefore, if the limitations of wearing glasses and contact lenses are a significant concern, vision correction surgery becomes a viable alternative. For individuals with abnormal vision who experience issues from wearing glasses or contact lenses, refractive lens surgery offers an effective solution.

Eye surgeries can be divided into two groups:
I. Corneal Surgery:

This type of surgery aims to correct the curvature of the cornea to adjust the refraction of light for clearer vision. Procedures include:
• LASIK: A laser is used to reshape the cornea.
• Femto-LASIK (Femtosecond Laser): Uses a femtosecond laser for more precision in creating the corneal flap.
• ReLex Clear (ReLex Clear): A minimally invasive procedure that reshapes the cornea without creating a flap.
Limitations:
• Not suitable for individuals with:
• Excessively steep or flat corneal curvature.
• Insufficient corneal thickness.
• Corneal sagging diseases.
• Chronic eyelid inflammation.
• Very dry eyes.
• Corneal wounds.

II. Lens Surgery:
There are two types of Lens Surgeries

• Intraocular Lens (ICL) Surgery:
This involves inserting a special type of soft, flexible polymer lens. The lens is placed behind the iris and in front of the natural lens.

Limitations:
Not suitable for individuals with narrow eye openings, glaucoma, cataracts, or corneal degeneration. Inserting extra lenses can worsen these conditions.
Patients with cysts on the back of the iris may experience lens movement, affecting vision quality.

If LASIK or ICL surgery is not suitable for you, refractive lens replacement surgery (RLS) becomes a valuable option. This procedure offers a permanent solution by addressing the eye's internal structure to correct vision abnormalities. It is particularly beneficial for individuals with refractive errors that cannot be corrected through less invasive methods, providing an effective and lasting improvement in vision quality.

• Refractive Lens Surgery (RLS):
This procedure involves replacing the natural lens with an artificial one to preserve and enhance vision quality.

Refractive Lens Surgery (RLS) is a procedure designed to remove the natural lens of the eye, which may be causing refractive errors such as nearsightedness, astigmatism, or farsightedness. The natural lens is then replaced with a new artificial lens. This surgery utilizes advanced computer technology to precisely calculate your eyesight, ensuring that the personalized lens provides vision that is as close to normal as possible.
RLS offers a permanent solution to correct vision by addressing the underlying cause of refractive errors, leading to improved and sustained vision quality.

Suitable Candidates for Refractive Lens Surgery (RLS)

• Those with Thin Corneas or Insufficient Corneal Curvature
• Those with Narrow Pupil or at Risk of Glaucoma or Cataracts
• Those with Corneal Degeneration
• Those with Cataracts
• Those Seeking to Reduce Dependence on Glasses or Contact Lenses:

Limitations of Refractive Lens Surgery (RLS)
• Loss of Natural Focusing Ability:
Accommodation Loss: The natural lens of the eye has the ability to focus, allowing us to switch from looking at distant objects to nearby objects seamlessly. This process, known as accommodation, involves the lens stretching and contracting to change the refraction of light.

Impact on Near Vision: After RLS, the artificial lens cannot replicate this accommodation ability. As a result, while distance vision may be significantly improved, near vision may require assistance.

Another method that enhances the ability to focus involves using current technology to wear multifocal lens IOLs (intraocular lenses) in conjunction with refractive lens replacement surgery. These lenses improve near vision distance.

Refractive Lens Surgery (RLS)

Surgery Time: Approximately 10 to 15 minutes. Recovery is quick, typically within a day, allowing you to resume normal activities soon after. However, it is crucial to maintain cleanliness during the first week post-surgery.

Risks After Surgery: The risks are comparable to or even less than those associated with cataract surgery. This is because RLS requires less energy to break down the lens than cataract surgery.

RLS is an excellent option for restoring high-quality vision, allowing for consistent and clear eyesight. It makes daily activities such as walking, running, exercising, and driving safer and more convenient. Additionally, RLS reduces the need for glasses and contact lenses, alleviating associated issues, and boosting confidence and peace of mind every day.

Currently, there are numerous treatment options available for correcting abnormal vision. However, not every method may be suitable for everyone. It is essential to understand the limitations of each technique and consult with an ophthalmologist for a detailed diagnosis of your eye health. This will help in making an informed decision and preparing adequately before undergoing vision correction surgery.

 
Col. Asst. Prof. Dr. Theeratep Tantayakom

Ophthalmologist

Cornea and Anterior Segment Diseases

Cornea and Vision surgery

Eye Center, Phyathai 2 Hospital