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Scleral Contact Lenses: Are They For You?

Scleral contact lenses are large, gas permeable lenses that rest on the white part of the eye known as the sclera. This differs from soft contact lenses which we fit to the cornea, the dome-shaped front of the eye. This unique design allows the lens to functionally replace the irregular cornea with a smooth optical surface to correct vision problems such as keratoconus (thinning and conical protrusion of the cornea) and other corneal irregularities. The space between the cornea and the back surface of the scleral lens acts as a liquid reservoir. This reservoir is filled with tears and provides comfort by lubricating the surface of the cornea to reduce dry eyes. 

Practically a scleral lens is a prosthetic cornea that recreates a perfect optical surface and makes vision a whole lot better. Let’s look at the following images that show what these menses look like:

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Scleral contact lenses are custom-made for patients and can provide better comfort and vision for those who have severe forms of:

• Keratoconus

• Ocular surface diseases (Sjogren’s, Steven’s Johnson Syndrome)

• Irregular astigmatism

• Highly irregular corneal transplants

• Post-refractive surgery complications (LASIK, PRK)

• Dry eye

Previously, scleral lenses have been reserved for only complex corneal and contact lens cases but are now gaining popularity and are being used for normal patients. Its distinct design provides increased comfort and stability on the eye leading to consistent vision, reduced glare and reduced dryness. Patients that have experienced poor comfort or vision with regular contacts may be good candidates for scleral lenses. 

Sources:

http://www.reviewofcontactlenses.com/content/d/rgp_lenses/c/52262/
http://www.allaboutvision.com/contacts/scleral-lenses.htm
http://cdna.allaboutvision.com/i/contacts-2016/scleral-lens-diagram-330×220@2x.jpg
http://cdna.allaboutvision.com/i/contacts-2016/scleral-lens-in-eye-330×220@2x.jpg

Neurolenses

Eye Motor Deficiencies:  Teaming, Focusing and Muscle Deficiencies

Clear vision is not the only important factor for comfortable vision. Equally important is when your eyes efficiently work together. This includes proper eye alignment and the ability to move the eyes smoothly together in all directions. Additionally, the tiny muscles located inside the eye must efficiently control our ”zoom” ability or near focus. Our brain, specifically our trigeminal nerve, senses when our eyes are out of alignment and compensates to help improve our focus. All of the compensation that we do can cause symptoms such as fatigue, headaches, neck pain, and discomfort in the eyes (asthenopia).

A variety of methods are used to help correct these vision-related issues. These include the standard methods of glasses or contact lenses but may also include Neurolens, prisms or over/under correcting lenses. Prisms can be prescribed in glasses that bend light and allow for comfortable vision when your eyes are not aligned normally. Over or under- correcting lenses serve to relieve or stimulate accommodation (focusing).

In the last few years we have improved our treatment of many eye misalignments. Using what is called a neurolens, we are able to better correct eye teaming issues. What is special about neurolens is its ability to correct distance ad near deviations in a single lens. This allows patients to be optimally corrected full-time. In fact, many patients respond so well that their symptoms are greatly reduced or eliminated after using the lenses for only a few weeks. If we are talking about a migraine or significant headache this can be life changing!

Vision Correction for High Prescriptions

Implantable Collamer Lens (ICL)

What is ICL?

Implantable collamer lens implants help patients see better without glasses or contacts. Unlike traditional contact lenses that go on the surface of the eye, the ICL is positioned inside the eye between the iris and the crystalline lens. Once Implanted, the lens stays indefinitely in the eye. However, if your vision changes dramatically over time, the lens can be easily replaced or removed and hence this procedure is reversible!

Who is a good candidate?

• High Myopes

•Patients between the ages of 21-45

• Patients with little or no astigmatism

• Patients with average or thin corneal thickness who may not be Lasik or PRK candidates

• Stable refractions with less than 0.50 diopters of change in two years

• Dry eye patients

Procedure

The ICL procedure is a short 15-minute outpatient procedure. Prior to the implantation of the Visian ICL, you will receive topical anesthetic drops to minimize discomfort. The doctor then creates a micro opening to insert the lens. The lens is folded and loaded into a small cartridge and as the lens is injected, it gently unfolds in your eye.

It is a simple procedure with fast recovery and provides youwith a fast vision change. So, if you are tired of bulky eyeglasses and contacts, ICL implants may be an option for you.

Addressing the Dress

The Dress Debate of 2015 has divided people around the world into two teams: Blue and Black versus White and Gold. However, this debate can be resolved with the knowledge that color is a visual perception, and is open to interpretation to all people. In our retinas, we have different color-sensing receptors that identify various levels of blue, red, and green. All of these different color sensors are stimulated in different amounts by light entering our eyes, and therefore, our brains interpret particular colors. However, it gets more complex, with the integration of the visual cues around The Dress that make us perceive two different color patterns. For example, if we take a color swatch from bright lighting conditions, and bring it into a shadow, our brain will perceive that color swatch as a darker color. Side-by-side, an identical color swatch can be perceived as two different colors! This is known as color constancy—a phenomenon that is responsible for causing the perceived color change based on surrounding colors and shadows. This further proves that we see the world with our brain, where the eyes are an eminent relay station, and that the brain itself is influenced by our experiences and assumptions.

Blog contribution by Anna Parfenova, Optometry Intern, College of Optometry, Western University of Health Sciences.

 

Could going to the movies be an indicator to get your next eye exam?

Could going to the movies be an indicator to get your next eye exam?

3da

In today’s world, 3D technology has become more popular and common in gaming systems, television, and especially movies. Most people are able to enjoy this thrilling experience through its realistic and close-up features. Nonetheless, there are some who find viewing 3D films gives them discomfort or makes them nauseated. According to the American Optometric Association (AOA), viewers who feel the 3 D’s of 3D viewing (Dizziness, Discomfort, or lack of perceived Depth perception) should get a comprehensive eye exam by an optometrists.

Studies indicate that the problem may arise from eye conditions known as amblyopia (a difference in visual strength between the two eyes) or strabismus (the misalignment of the eyes). However, one of the biggest problems with 3D is the inability to accommodate. When we look at something close, our eyes have a “near reflex”—accommodation, convergence, and miosis (pupils get smaller). Convergence occurs when an object is pointed towards your nose. The muscles that control your eyeballs work in sync by rotating them inwards. You can try this by placing your finger 6 inches away from your friends face—you’ll notice that your friend will now look cross-eyed. Accommodation occurs when you are focusing on near objects. These functions are all completely normal in the real world. In a 3D movie however, when we see objects coming towards us, we converge but don’t accommodate—thus only two of the three “near reflexes” are working normally. This inability to perform all three “near reflexes” may cause eye discomfort or headaches.

If these problems continue to persist, one of the solutions may be to get your eyes checked by an eye doctor. Not only can a strabismus or the inability to accommodate  prevent you from watching 3D movies, it can also cause difficulties in other aspects of your life.

Blog contribution by Jeffrey Dang, Optometry Intern, College of Optometry ,Western University of Health Sciences