Please ensure Javascript is enabled for purposes of website accessibility Things You Should Know About Contact Lenses
Dr. D. Y. Patil Vidyapeeth, Pune
(Deemed to be University)
Dr. D. Y. Patil Institute of Optometry & Visual Sciences
Pimpri, Pune-411 018 (Maharashtra) India.

Things You Should Know About Contact Lenses

Things You Should Know About Contact Lenses

Are you planning to replace the spectacle with contact lenses? This post will help you to understand common factors about contact lenses.

Mohit Baranwal (T.y. B. Optom)
March, 18 2023

Contact lenses are one of the most suitable options for those who don't want to wear specs or undergo a full LASIK surgery.

Many people are afraid to use contact lenses because of misconceptions, less knowledge, or some other reasons.

If you are a first-time wearer or want to wear contact lenses, this article is for you. In this article, we will discuss most of the things that you should know about contact lenses.

Contact Lenses Materials

When considering contact lenses choosing the right material is very important for you. Mainly there are three materials:

Soft Lens

These are hydrogel lenses, which are made from a combination of water in cooperated plastic and gels. These lenses are thin, and flexible and take the shape of your cornea. Hydrogel contact lenses contain 40 to 75 percent (by weight) water content. Hydrogel lenses can be ionic or non-ionic.

Ionic lenses are negatively charged which attract positively charged protein on the tear film. Non-ionic lenses are surface treated to make them less deposit prone.

Silicone Hydrogel

Silicone hydrogel lenses are an updated version of hydrogel lenses that are more porous and allow more oxygen to pass through the lens and reach the corneal surface. These are the most common lens used in nowadays practice.

Gas Permeable Lens

It is also called GP lens or rigid gas permeable lenses (RGP). Their diameter is smaller than the usual silicone hydrogel or hydrogel lenses. These lenses are very good when it comes to correcting astigmatism. RGP lenses take some time to adjust, but after adjusting most people report it as more comfortable than soft lenses.

Contact Lens Wearing Time

Contact lenses are needed to be replaced from time to time to prevent the build-up of deposits and contamination which increases the eye infection.

Soft contact mode of wear is-

  • Daily wear – replaced after a single day of wear.
  • Disposable wear – replaced after 2 weeks or sooner.
  • Frequent wear – replaced monthly or quarterly.
  • Traditional or reusable wear- replaced after every six months or longer.

RGP lenses or GP lenses are less deposit prone, so they don't need to be replaced as frequently as soft lenses. Generally, GP lenses can be worn for yearlong or more before they were replaced.

Contact Lens Design

There is a variety of designs available in contact lenses according to the need of the patient.

  • Spherical Contact Lenses – they have the same power throughout the whole contact lens.
  • Toric Contact Lenses – they have two different powers in different meridians to correct astigmatism.
  • Multifocal Lenses – these lenses contain different power zone for near and distance prescription. It can also correct astigmatism.
  • Cosmetic lenses – these change or intensify the color of the eye.

Indications of Contact Lenses

  • Refractive Error correction – for myopia, astigmatism, hypermetropia, and presbyopia.
  • Keratoconus
  • Corneal protection- using soft bandage contact lenses.
  • Drug Delivery – Ocusert is used to deliver the drug pilocarpine.
  • Masking iris abnormalities such as – coloboma, albinism, aniridia, etc.

Contra Indications of Contact Lenses

  • Those who cannot or are not able to take proper care of contact lenses.
  • Suffering from any infection or inflammation such as – uveitis, or keratitis.
  • Bacterial infection in any one eye.
  • Having a severe case of dry eye syndrome.
  • Systemic conditions such as facial nerve palsy or Sjogren syndrome.
  • Corneal neovascularization – cornea is an avascular structure, but certain ocular conditions can cause blood vessels to emerge in the cornea.
Benefits of Eyeglasses a Comprehensive Guide
Benefits of Eyeglasses a Comprehensive Guide

Eyeglasses do more than improve vision. Explore how they protect your eyes, boost safety & confidence, and become a stylish accessory.

Read More
Exploring Scope of Bachelor of Optometry (B. Optom.) in India
Exploring Scope of Bachelor of Optometry (B. Optom.) in India

Explore scope of Bachelor of Optometry in India. Discover career opportunities, salary prospects, and future trends in optometry profession.

Read More
A Guide to Keeping Your Eyes Safe From UV Rays
A Guide to Keeping Your Eyes Safe From UV Rays

Discover essential tips for shielding your eyes from harmful UV rays. Learn about sunglasses, hats, and more to safeguard your vision.

Read More