2025-07-08
Understanding the Different Types of Contact Lenses
As an optometrist with years of experience, I often find new contact lens wearers – and even long-time wearers – are surprisingly unaware of the breadth of options available. It's not a one-size-fits-all world, and choosing the right lens is crucial for comfort, vision correction, and eye health. This post will walk you through the major categories, explaining the pros, cons, and ideal scenarios for each. We’ll go beyond just “soft” versus “hard” and dive into the specifics.
What's the difference between soft and rigid gas permeable (RGP) lenses?
This is the foundational distinction. Soft lenses, as the name implies, are made of flexible, hydrophilic (water-attracting) materials. Think of them as being similar in consistency to a very soft gel. They’re comfortable to wear initially, and many people adapt to them quickly. The vast majority of contact lens wearers choose soft lenses. They come in a massive range of designs for different prescriptions and needs.
Rigid Gas Permeable (RGP) lenses, sometimes called “hard” lenses (though modern materials are much more comfortable than the old plastics), are made of a firm, durable plastic that allows oxygen to reach the cornea. While they might feel slightly less comfortable at first, they offer several advantages, particularly for specific vision problems. We’ll cover those later. RGP lenses hold their shape, providing sharper vision, and tend to be more resistant to deposits.
What are the different types of soft contact lenses?
Soft lenses are broken down further based on replacement schedule and material. Here’s a rundown:
- Daily Disposables: These are designed for one-time use. You wear them for a day, then discard them. They’re the most hygienic option as you’re always fitting a fresh, clean lens. They’re also great for people who only wear lenses occasionally (sports, special events) as there's no cleaning solution or case required. Cost is higher per lens, but the convenience and reduced risk of infection often outweigh this. Expect to pay roughly $35-$60 CAD per box of 30 lenses, depending on astigmatism correction (see below).
- Two-Weekly Disposables: These are worn for two weeks and then replaced. A good balance of cost and convenience. They require diligent cleaning and storage. Costs typically range from $40-$70 CAD per box of 6 lenses.
- Monthly Disposables: Worn for a month, these offer the lowest per-lens cost but require the most dedicated cleaning and care. They’re suitable for stable prescriptions and regular wearers who are comfortable with a consistent cleaning routine. Pricing is around $50-$80 CAD per box of 6 lenses.
- Silicone Hydrogel Lenses: This isn’t a replacement schedule but a material. Silicone hydrogel allows significantly more oxygen to reach the cornea than traditional hydrogel lenses. This reduces dryness and discomfort, especially during extended wear. Most modern daily, two-weekly, and monthly lenses are now made of silicone hydrogel.
- Toric Lenses: These are specifically designed to correct astigmatism (an irregular curvature of the cornea). They have a unique shape that aligns with the astigmatism, providing clearer vision. They are available in all the replacement schedules listed above, and can add $10-$20 CAD to the cost of a box, depending on the severity of the astigmatism.
- Multifocal Lenses: For those with presbyopia (age-related difficulty focusing on near objects), multifocal lenses provide clear vision at both distance and near. Similar to progressive glasses, they have different zones of focus. They require a period of adaptation, and not everyone achieves perfect near vision.
What are the advantages of RGP lenses?
While soft lenses dominate the market, RGP lenses remain the gold standard for certain situations:
- Keratoconus: This condition causes the cornea to thin and bulge. RGP lenses can provide a more stable and comfortable fit than soft lenses, correcting vision and slowing the progression of the disease.
- High Astigmatism: Sometimes, the astigmatism is too complex for a toric soft lens to correct adequately. RGP lenses can offer sharper vision in these cases.
- Dry Eyes: While seemingly counterintuitive (they don’t hold as much water), RGP lenses allow more oxygen to reach the cornea, which can reduce dryness and discomfort for some people. They also don't absorb tear film like soft lenses, leaving more moisture on the eye’s surface.
- Improved Vision Quality: Because they hold their shape, RGPs generally provide sharper, crisper vision than soft lenses, especially at higher prescriptions.
The downside? RGP lenses take longer to adapt to, require more meticulous cleaning, and can be more fragile. A full set of RGPs (two lenses) typically costs between $200 and $400 CAD, and needs to be replaced every 1-3 years, depending on care and material.
What about specialized lenses – scleral and orthokeratology?
These are less common but important options:
Scleral Lenses: These are large-diameter RGP lenses that vault over the cornea and rest on the sclera (the white part of the eye). They’re used for severe corneal irregularities, dry eyes, and post-surgical complications. They provide a smooth optical surface and keep the cornea hydrated. They’re significantly more expensive than standard RGPs, often costing $600-$1000+ CAD per lens.
Orthokeratology (Ortho-K): This involves wearing specially designed RGP lenses overnight to temporarily reshape the cornea. You remove the lenses during the day and can see clearly without glasses or contacts. It’s primarily used for mild to moderate myopia (nearsightedness) and is popular amongst athletes and active individuals. It requires a precise fitting and consistent wear. Expect to pay around $800-$1500 CAD for the initial fitting and lenses.
How do I choose the right lens?
It’s tempting to try and self-diagnose, but a comprehensive eye exam is essential. We’ll assess your vision, corneal health, tear film quality, lifestyle, and preferences to determine the best lens for you. Factors like how often you'll wear them, your environment (dusty, dry), and your budget all play a role. Don’t be afraid to ask questions and discuss your concerns. We can trial different lens types to ensure a comfortable and successful fit.
Here in Okotoks, Alberta, we see a lot of patients enjoying outdoor activities. For those individuals, daily disposables are often a great choice, minimizing the risk of irritation from dust or allergens. The dry climate can also make silicone hydrogel lenses a beneficial option for increased comfort.
Remember, wearing improperly fitted or cared-for contact lenses can lead to serious eye infections. Prioritize your eye health and work with a qualified optometrist to find the perfect fit.