Replacing Glasses with Contact Lenses – What is Important to Know

During the summer, many people who wear prescription glasses choose to replace them with contact lenses because this way they can also use their sunglasses. Transitioning from prescription glasses to lenses seems simple, but it is not.

See the advice of Dr. Ina Antonova, a trainee ophthalmologist at the Specialized Eye Hospital ‘PENTAGRAM’. If you are going to use lenses for the first time, this information will certainly be useful to you.

Why switch to contact lenses?

Contact lenses are an excellent alternative to glasses and can provide:

• A better appearance, without frames in front of your eyes;
• Convenience during sports and an active lifestyle;
• No fogging in humid weather or while wearing a mask;
• More comfort during certain activities, especially when working in a dynamic environment.

What prescription strength should your contact lenses be?The prescription strength of contact lenses is not always the same as that of glasses:

• If the glasses have a prescription up to ±4.00, the lenses are usually of the same strength.
• For prescriptions over ±4.00 or in the presence of astigmatism, the lenses must be recalculated by an eye doctor who uses special correction charts.

Types of contact lenses and how to choose the right ones. By wearing duration:

• Daily lenses – worn for one day and then discarded. The most hygienic and easiest option to maintain.
• Monthly, weekly, and other lenses – require daily cleaning and proper storage. Removed every evening.
• There are lenses specifically designed for people who need to sleep with them
  (e.g., emergency teams). They are cleaned according to a strict schedule. (!) It is recommended never to sleep with contact lenses, as this carries a risk of corneal injury and infection, which can threaten vision.

According to the material:

• Soft lenses – the most commonly used, comfortable, and easy to adapt.
  • Hydrogel lenses – cheaper and thinner.
  • Silicone-hydrogel lenses – more durable, easier to put on, especially for beginners.
• Rigid lenses – used in specific cases, e.g., high diopters or corneal diseases.

Studies have not found differences between hydrogel and silicone-hydrogel lenses in terms of comfort and safety. Each patient should choose the material they feel most comfortable with. The materials differ in terms of their oxygen permeability, which is essential for the cornea.

Specialized lenses:

• Toric lenses – for astigmatism correction above 1.00 diopters. Require prescription and fitting by a specialist.
• Multifocal lenses – for people with presbyopia (the need for reading glasses). Suitable for both near and distance vision needs simultaneously. Require prescription and fitting by a specialist.

How to insert, remove, and maintain your contact lenses?

Insertion:
1. Wash and dry your hands thoroughly.
2. Remove the lens with your fingers (without nails).
3. Rinse the lens with lens solution. Never use tap water.
4. Place the lens on the tip of your index finger. Check that it is not inside out (it should look like a bowl or a perfect hemisphere, not with the edges flared out).
5. Use your other hand to hold your upper eyelid, and with a free finger from the hand holding the lens, pull down the lower eyelid.
6. Place the lens on your eye. You may look straight ahead or upward.
7. Close your eye and rotate it slowly to center the lens. Open your eye and blink.

Removal:
1. Wash and dry your hands thoroughly.
2. Look upward.
3. With the index finger of your non-dominant (less comfortable) hand, lift your upper eyelid.
4. With the middle finger of your dominant (comfortable) hand, pull the lower eyelid downward.
5. With the tips of your index finger and thumb of your dominant (comfortable) hand, carefully pinch the lens and pull it out. Do not use nails or apply strong pressure.
6. Place the lens in your palm, ready for cleaning.

If you encounter difficulties:

• Use preservative-free moisturizing drops.
• Try sliding the lens towards the white of the eye or towards the lower eyelid, where it detaches more easily.
• If the lens is folded, drip solution and gently manipulate it until it unfolds.

On the internet, there are useful videos that show how to put on and take off lenses. (!) Don’t worry – it is impossible for the lens to “go behind your eye” if it gets under your eyelid. Use artificial tears, look strongly downward, gently massage your eyelids until part of the lens appears under the eyelid, then carefully move it onto the cornea or the visible part of the sclera with your finger and remove it as described above. If unsuccessful, you can try flipping the upper eyelid. (!) If you are unable to remove the contact lens, seek an ophthalmologist as soon as possible.

How to clean and store contact lenses?

After removal, contact lenses should be cleaned and stored in a special case with disinfectant solution.

1. Cleaning after removal:

• Place the lens in the palm of your clean hand.
• Drop a few drops of disinfectant solution.
• Gently rub the lens back and forth with your fingertip (avoid nails).
• Rinse the lens with more of the same solution.

2. Storage:

• Pour fresh storage solution into the lens case and place the lenses inside.
• Seal tightly and leave overnight.
• For each subsequent use, always discard the old solution, rinse the case with fresh solution, and leave it to dry upside down on a clean tissue.
• Replace the case every 3 months.
• Follow the instructions for safe use if you have kept the lenses in the same solution for too long.

Additional recommendations:

• Contact lenses should be applied before putting on makeup.
• Never wet a lens with saliva or put them in your mouth – this carries a serious risk of eye infection.
• Lenses should only be stored in a special disinfectant solution – never in water or other liquids.
• There are different types of solutions – multifunctional ones are most commonly used, but in cases of allergies or lenses made from specific materials, special products may be required. Always follow the manufacturer’s instructions.

What are the risks of improper use of contact lenses?

The most serious risk of improper lens use is the risk of corneal infection from bacteria, fungi, or other dangerous microorganisms – this can lead to corneal clouding and permanent, irreversible vision loss.

Risks include:

• Contact with water (bathing, swimming, sauna) – increases the risk of lens contamination and infections. Swimming with goggles and contact lenses should be done with caution. The safest option is to use prescription swimming goggles.
• Using contact lenses in highly dusty and polluted environments
• Sleeping with lenses – increases the risk of injuries and inflammations
• Rubbing your eyes with lenses – may cause corneal scratches or lens displacement, leading to discomfort and a risk of complications.
• Dry eye syndrome – in such cases, lenses should be worn with extra caution and under the supervision of an ophthalmologist.
• Eye inflammations (conjunctivitis, keratitis, uveitis, etc.) – lenses should not be worn in such conditions. They can worsen the inflammation and hinder treatment.
• Eye allergies – during an allergic episode, it is best to remove the lenses and use glasses.
• Eye drops – in most cases, they are not used together with contact lenses, as some ingredients interact with the lens material and have a toxic effect. Only preservative-free artificial tears are safe to use while wearing lenses.

What to do in case of complaints?

If, while wearing lenses, any of the following occurs:

• Redness of the eyes
• Tearing
• Burning, stinging, or irritation
• Reduced or blurred vision
• Pain or increased sensitivity to light

These are alarming symptoms – it may involve a corneal infection which, if not treated promptly, can lead to blindness.

Immediate actions:

1. Remove the contact lenses immediately.
2. Do not put them back on even if the symptoms improve.
3. Seek an eye doctor as soon as possible.

Sources:
https://www.aao.org/eye-health/glasses-contacts/contact-lens-care
https://coopervision.com/contact-lenses-and-vision
https://www.bauschandlomb.in/lens-article/5-factors-of-proper-contact-lens-cleaning
https://www.acuvue.com/en-sg/considering-contacts/new-contact-lenses/

https://eyewiki.org/Contact_Lenses
https://www.cdc.gov/contact-lenses/about/index.html
https://patient.info/doctor/contact-lenses-types-and-care