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Visual Field

Visual field testing is an important part of most standard comprehensive eye exams. Also sometimes known as perimetry testing, Visual field testing is a method to measure the entire scope of vision of an individual, including their peripheral/side vision.
 

The importance of visual field testing

Visual field testing is one of the most effective diagnostic treatments in the detection of glaucoma. This is because when patients are affected by glaucoma, it is usually the peripheral vision that is affected by their condition first. However, it can also be used to detect central or peripheral retinal diseases, eyelid conditions such as drooping, optic nerve damage and conditions that affect the visual pathways from the optic nerve to the area of the brain where this information is processed into vision.
 

Visual field testing is also an important part of monitoring for people who are considered to be at risk for vision loss from disease and other problems, including those who have been diagnosed with the following:

  • Multiple sclerosis

  • Hyperthyroidism

  • Pituitary gland disorders

  • Central nervous system problems (such as a tumor that may be pressing on the brain)

  • Stroke

  • Diabetes

  • High blood pressure
     

What to expect from visual field testing

There are a variety of methods that can be used to perform visual field testing, including:
 

Static automated perimetry. This is where a machine is used to quantify how well the patient is able to detect flashing lights of varying size and brightness in different areas of their visual field, while they concentrate on a central point. The patient responds by pushing a button when they see the light.

Kinetic perimetry. This involves points of light that are fixed in size and intensity and are presented along the patient’s peripheral vision, before being gradually moved inwards to determine their field of vision. 

Visual field testing is non-invasive, painless and doesn’t require patients to have their eyes dilated. The results, which are usually presented in a series of charts, are digital and sent directly to your eye doctor for interpretation. Depending on the outcome of your results, you may be recommended for further diagnostic testing which could include blood tests. If you have been diagnosed with glaucoma, you will probably be recommended to have several visual field tests each year, which will help your eye doctor to monitor the progression of your condition and recommend treatments to slow it.

If you would like more information about visual field testing, or if you have concerns about your peripheral vision, please don’t hesitate to schedule an appointment with our experienced and knowledgeable eyecare team today.


Lens Technology

Thanks to the advancement of lens technology, glasses lenses are no longer a single, one size fits all solution. There are a variety of different lens types that can be used in glasses, giving patients greater flexibility and control over their vision than ever before.
 

Single Vision Lenses

Also known as monovision lenses, these lenses are designed to correct the wearer’s vision at just one distance, and have a single prescription covering the entire surface of the lens. They are most often recommended for people who are either nearsighted (myopia) or farsighted (hyperopia) and who need glasses for a specific activity, such as driving or reading.
 

Progressive Lenses

Progressive lenses are multifocal lenses that can correct a patient’s vision at different working distances, ranging from far distance to reading distance. However, rather than designating different areas on the lenses for different distances with visible lines separating them, progressive lenses have a gradual change so that the wearer can smoothly transition from one lens power to another.
 

Bifocal and Trifocal Lenses

As you may have guessed from the name, bifocal and trifocal lenses have either two or three lens powers depending on which type you choose. Bifocal lenses support distance vision in the top half of the lens, and near vision in the lower half. Trifocal lenses support distance vision in the top third of the lens, intermediate vision in the middle segment and near vision in the bottom third. Whichever variety you choose, you will see visible lines separating each segment.

Bifocal and trifocal lenses are recommended for patients who are near or farsighted, and those who develop presbyopia, which is the natural hardening of the eye lens, that occurs as we get older. Presbyopia makes it harder for the lens of the eye to adapt to focus at different distances.
 

Multifocal Lenses

Multifocal lenses are the alternative name given to bifocal, trifocal and progressive lenses.
 

Computer Lenses

Computer lenses are prescription lenses that are specifically designed to be worn when doing computer work. This is because they place the optimum lens power for viewing your computer screen exactly where you need it – which is closer than intermediate vision, but further away than reading material is usually held. Wearing computer lenses can significantly reduce the negative effects caused by the high visual demands of computer work, including blurred vision, redness, dry eyes, double vision and dizziness.
 

Transition Lenses

Also known as photochromic lenses, transition lenses are a special type of lens that darken when in the sunlight and lighten when in softer light or the dark. This versatility gives the wearer the convenience of being able to move between different environments without needing to change their glasses. This makes them extremely cost effective and prevent the wearer from needing to take multiple pairs of glasses out with them. Transition lenses also filter out many of the harmful UV rays that are emitted from the sun, helping to keep eyes healthy too. They are ideal for people who spend a lot of time going between inside and outside, or who work outside in varying weather conditions.
 

Blue Light Lenses

Blue light lenses are specially crafted lenses that contain filters that block out much of the artificial blue light that is produced by digital devices like computers, smartphones and tablets. Natural blue light is actually good for balancing our sleep-wake cycle, boosting our mood and enhancing our cognitive abilities so that we can function better day to day. However, too much blue light, especially from artificial sources, can have the opposite effect. Many people who fail to use blue light lenses can go on to develop digital eye strain, which produces symptoms like eye fatigue, dry eyes, blurred vision, headaches and more. Blue light lenses are recommended for anyone who spends a lot of time working on a digital device.
 

Polarized Lenses

Polarized lenses are used to reduce eyestrain and improve the quality of vision in patients on especially sunny days, making them ideal for anyone who spends a lot of time outdoors. They can do this because they have a special filter that blocks some of the light from passing through the lens. Vertical light is allowed to pass through, while horizontal light, such as that which bounces off of water and can be blinding, is blocked. Polarized lenses are most often used in sunglasses since they are worn outdoors, and the wearer also needs to protect their eyes from UV damage.

Still have questions about which lens is right for you? Contact us to schedule an eye exam or an appointment to evaluate your individual needs.


Specialty Contact Lenses

Every patient is different and so are their eyes. This means that there need to be different types of contact lenses to suit each individual. Some patients have corneal abnormalities which mean that conventional lenses won’t sit comfortably on the surface of their eyes, while others suffer from eye conditions that mean normal contact lenses won’t be comfortable or could irritate their eyes. 

As you may have guessed from the name, specialty contact lenses are unconventional contacts that are designed for patients that regular contacts might not be suitable. Here are some of the main types of speciality contact lenses and who they are recommended for. 
 

Who might be a good patient for specialty contact lenses?

Some of the patients that might benefit from specialty contact lenses include those who:

  • have been diagnosed with dry eye syndrome

  • have corneal scarring

  • have been diagnosed with keratoconus, a condition characterized by the bulging of the cornea

  • suffer from strabismus, a condition where the patient has an eye that turns in or out relative to the other

  • have suffered an injury to the eye

  • suffer from a peripheral corneal thinning disorder

  • are intolerant to other types of lenses


Your eye doctor or contact lens provider will be able to tell you if you need specialty contact lenses and if so, which lenses would be best based on your individual requirements. 
 

Rigid Gas-Permeable Lenses

Also known as RGP lenses, these are made from a special material that allows oxygen to pass through them and reach the surface of the eyes. This helps to keep the eyes hydrated and comfortable, making these lenses easier to wear, especially for patients who suffer from dry eyes. Dry eyes aren’t just a symptom, but a very real condition, characterized by dry, stiff, and uncomfortable eyes, blurred vision, and eye fatigue. RGP lenses are more rigid than soft lenses, and this helps to keep them stable and secure on the eyes so that patients can enjoy sharper vision. They also help the cornea to maintain its shape, which helps to minimize the effects of some corneal abnormalities. 
 

Limbal Fit Contact Lenses

Limbal contact lenses are another type of specialty lens that falls between rigid gas-permeable lenses and scleral varieties in terms of their size. Their larger overall diameter helps to increase their stability on the surface of your eyes. They also offer minimal interference with the eyelids, which helps to ensure comfort and clarity of your vision.
 

Hybrid Contact Lenses

Hybrid contact lenses are a combination of both soft and gas-permeable contact lenses, giving patients the opportunity to enjoy the best parts of both designs. The middle part of hybrid lenses is made from gas-permeable material that lets oxygen pass through to the eyes. However, the gas-permeable part of the lens is more rigid, and this firmer center gives the lens greater stability and the patient enhanced clarity. The RGP portion of the lens also helps to trap a tear film between the cornea and the lens so that the eye remains hydrated. Meanwhile, the outer edge of hybrid lenses is a soft lens skirt. This means that patients don’t have to deal with the hard edges associated with RGP lenses that may be uncomfortable. Instead, the comfort levels that patients experience are more like wearing fully soft lenses. 

For more information about specialty contact lenses, don’t hesitate to speak to our dedicated eye care team. 


Cosmetic Services

We all want to look our best and in the last decade, we have seen a significant increase in the number of people seeking cosmetic services in order to enhance their appearance. With our eyes being our most distinguishing feature, we want to make the most of them. Thankfully there is now a range of cosmetic services that can help to rejuvenate our eyes and the area around them to keep them fresh, young and wrinkle-free. 

Let’s take a look at some of the services on offer.
 

Pigment removal

The brown pigment spots that appear on the face are often referred to as age spots and are a result of sun exposure. With age, the repeated exposure to UV rays causes melanin, a compound that is responsible for pigmentation and protecting the skin begins to clump together to form an area of hyperpigmentation. Whilst they aren’t any cause for concern, many people feel that they look unsightly. Luckily, there are a number of different treatments that you can get to remove them including topical creams, laser therapy, and chemical peels.

If you are suffering from darker pigmentation then we strongly recommend that you make an appointment with a qualified dermatologist who will recommend the best course of treatment for you, based on your specific needs.
 


Limbal Relaxing Incisions

Astigmatism is a relatively common eye disorder that causes the vision to be blurred or distorted. It occurs when the lens part of the eye, known as the cornea, isn’t perfectly curved and instead resembles a football rather than a soccer ball. This means that the light entering the eye comes through at a distorted angle, making the object appear blurry and out of focus. There are several ways in which it is possible to treat astigmatism, including laser eye surgery and corrective lenses. However, another possibility is a solution referred to as limbal relaxing incisions.
 

What are limbal relaxing incisions?

Limbal relaxing incisions are microscopic cuts to an area in the eye known as the limbus. This helps to relax the curve in the cornea and improve its ability to focus light correctly. It can significantly improve your astigmatism and the overall quality of your vision.
 

Am I a good candidate for limbal relaxing incisions?

If you have astigmatism, are over 18, in good general health and have no major eye conditions, then chances are you are a good candidate for limbal relaxing incisions. Make an appointment with your eye doctor to discuss your candidacy further.


Refraction Test

A refraction test, also called a vision test, is usually performed as a part of a routine eye examination. The purpose of this test is to determine if a person has a refractive error which would then mean the patient would need glasses or contact lenses.
 

What Is The Normal Value for Refraction Test?

A value of 20/20 is normal (optimum) vision. This means that individuals who have 20/20 vision are able to read letters that are 3/8-inch (1 centimeter) tall from 20 feet (6 meters) away. The normal uncorrected vision (without glasses or contact lenses) refractive error is zero (plano). Individuals who don’t have 20/20 vision, have what is called a refractive error. A refractive error means that the light is not bending properly when it passes through the lens of the eye. The refraction test will tell the doctor what prescription lens should be used in order to have 20/20 vision.

For people over age 40 who have normal distance vision but difficulty with near vision, a refraction test with a small type size is used to determine normal near vision and the correct power of reading glasses.
 

How Is The Refraction Test Performed?

The test is performed by having the patient seated in a chair that has a special device (called a phoropter or refractor) attached to it. The patient looks through the device and focuses on an eye chart 20 feet (6 meters) away. The device contains lenses of different strengths that can be moved into the patient’s view. The test is performed one eye at a time. If the patient is wearing contact lenses, they should be removed before the test.

In case the final vision is less than 20/20 even with lenses, then there is probably another non-optical problem with the eye. The vision level achieved during the refraction test is called the best-corrected visual acuity (BCVA).
 

What Are The Causes of Abnormal Refraction Test Results?

  • Abnormal results may be due to:

  • Astigmatism (abnormally curved cornea causing blurred vision)

  • Hyperopia (farsightedness)

  • Myopia (nearsightedness)

  • Presbyopia (inability to focus on near objects that develop with age)
     

Other conditions under which the test may be performed:

  • Corneal ulcers and infections

  • Loss of sharp vision due to macular degeneration

  • Retinal detachment (separation of the light-sensitive membrane (retina) in the back of the eye from its supporting layers)

  • Retinal vessel occlusion (blockage in a small artery that carries blood to the retina)

  • Retinitis pigmentosa (an inherited disorder of the retina)
     

There is an art to refraction and the optometrist will always answer the patient’s questions and as well as discuss their findings. Based on the results of the refraction test, they can determine the amount of myopia, hyperopia or astigmatism.
 


What to Expect During an Eye Exam

The parts of a comprehensive eye examination vary according to the patient's age, date of last exam, and other factors. Not all parts of the eye exam may be needed or performed, but the first part of the eye exam will include documenting medical history. Here are some eye and vision tests that are likely to be encountered during a comprehensive eye exam:
 

Visual Acuity Tests

Visual acuity tests measure the sharpness of vision and are usually performed using a projected eye chart to measure the distance visual acuity and a hand-held small acuity chart to measure the near vision (for reading).
 

Color Blindness Test

A screening test that checks the color vision is often performed early in a comprehensive eye exam to rule out color blindness.
 

Cover test to check eye alignment.

A test used to assess strabismus or a more subtle binocular vision problem that could cause eye strain or amblyopia (lazy eye).
 

Ocular Motility (Eye Movements) Testing

Ocular motility testing is performed to determine how well eyes can follow a moving object and/or quickly move between and accurately fixate on two separate targets.
 

Stereopsis (Depth Perception) Test

This is used to test perception of depth and 3-dimensional structure obtained on the basis of visual information deriving from two eyes by individuals with normally developed binocular vision.
 

Retinoscopy

This test is used to estimate which lens powers will best correct distance vision. Based on the way the light reflects from the eye, the doctor is able to obtain an approximation of the eyeglass prescription. This test is useful for children and patients who are unable to accurately answer the doctor's questions.
 

Manual refraction with a phoropter.

This is the test used to determine the exact eyeglass prescription.


Macular Degeneration

Macular degeneration, commonly referred to as age-related macular degeneration (AMD), is the single largest cause of sight loss in the developed world and affects more than 10 million Americans. It usually affects people over the age of 60, but has been known to affect those who are younger. It is a painless condition that usually affects both eyes with the loss being experienced in the central vision. It does not affect the peripheral vision, meaning that it does not cause total blindness.
 

What is the macula?

The macula is the most sensitive part of the retina and is responsible for our central vision and what allows us to see fine details with clarity.
 

Varieties of AMD

 

Wet AMD

Wet AMD is one variety of the condition in which abnormal blood vessels grow into the macula, leaking blood or fluid which then causes scarring and a rapid loss of central vision. Wet AMD can develop suddenly and rapid referral to a specialist is essential as it can be treated if caught quickly.
 

Dry AMD

Dry AMD is the most common variety of age-related macular degeneration and is a gradual deterioration of the retina as the cells die off over time and are not regenerated. Up to 15% of people with dry AMD go on to develop wet AMD, and so any sudden changes in your vision should be followed up with your optometrist as soon as possible.
 


Pink Eye

When you were a kid, did you experience your eyes become reddish and all of a sudden, someone close to you was also suffering from it? Your eyes, as well as those who contracted it, got itchy and swollen, right? Then it must have been that you were suffering from pink eye.

Pink eye is well known as conjunctivitis and it is the infection or inflammation of the conjunctiva or the transparent membrane that serves as a covering for the white part of the eye called the sclera that lines the eyelid. In addition to inflammation, there is usually tearing in the eyes that emits a sticky discharge which develops into a crust while one is sleeping, making it difficult for the patient to open their eyes in the morning.

One thing about the pink eye, which could affect one or both eyes, is that it is highly contagious. While it is more common in children, adults can also victims of this eye condition. Here are the 3 major causes of pink eye:
 

Bacteria

Streptococci and staphylococci are bacteria types that are most responsible for pink eye. However, chlamydia and gonococci can also cause pink eye. It is accompanied by serious eye pain, itching, swelling, redness, and discharge. The spread of bacterial pink eye is usually as a result of using personal items of infected parties, such as makeup or makeup tools that have been infected with bacteria or putting dirty hands in the eyes. If not treated, it can last for more than 10 days, but if treated, it should resolve in less than 3 days.
 

Allergies

Pink eye caused by allergies is followed by serious itching and tearing of the eyes. Pain is minimal, but it typically comes with quite a bit of discomfort. Most of the time, pink eye is accompanied by sneezing or coughing. Allergens that trigger pink eyes include grass, dust, pollen, mold, and ragweed. Allergy based pink eye is not usually contagious.
 

Viruses

Viruses such as the adenoviruses and herpes virus are the most common causes of pink eye. When a virus is the cause, there is usually a lot of teary discharge accompanied by nasal congestion, puffy eyelids, runny nose, and sharp pain. It is usually contracted from cough and sneeze droplets from an infected individual. It can take as long as 2 weeks to treat depending on the seriousness of the infection.

General Symptoms of Pink Eye:

  • Itchy eyes

  • Redness of the sclera

  • Pain

  • Watery discharge

  • Swollen eyelids

  • Hazy or blurry vision

  • Oversensitivity to light
     

Prevention

The best way to prevent pink eye is by practicing good hygiene which includes:

  • Avoid putting dirty hands in your eyes

  • Make it a habit to wash your hands often

  • Avoid sharing towels and other personal items

  • Do not use dirty items

  • Changing your pillow cover regularly

  • Do not leave a makeup item open for too long

  • Avoid sharing makeup items like eyeliners, mascara, etc.
     

Treatment of Pink Eye

  • The treatment of pink eye is dependant on its underlying cause. If it is caused by a virus, you just might have to wait for the virus to run its course which could last for about four to seven days. Virus caused pink eye could be easily contracted so it is imperative to try and prevent further spreading. Viruses cannot be cured by antibiotics, but some antiviral drugs could be helpful.

  • Antibiotics are most effective against pink eye caused by bacteria as they reduce the lifespan of these bacteria and could come in the form of eye drops or pills. Based on the doctor’s prescription, an eye drop should be administered about four to six times daily. It is important you finish using your drugs even after the disappearance of symptoms.

  • To deal with pink eyes caused by allergies, the allergy should be treated. Once treated, pink eye should disappear. It is also important to avoid allergens as much as possible so as to avoid pink eye.
     

Whenever the symptoms of pink eye emerge, the best preventive measure is to stay at home until the watery discharge ceases to avoid the spread of the bacteria or virus. You should also visit your doctor immediately to begin treatment. While mild pink eyes generally go away on its own, some of the more serious forms can cause a scar on the cornea.


Demodex

What Is Demodex?

The Demodex mite is a type of parasite that lives on humans and can reside in hair follicles and sebaceous glands. These mites are arachnid (eight-legged) and invisible to the naked eye, varying in size from 0.1mm to 0.4 mm long. They typically live on the face and in the hair follicles of the eyebrows, eyelids, roots of the eyelashes, facial hair, and around the ears and are associated with various skin problems of the eyes and face, such as blepharitis and acne rosacea.

Demodex can affect humans at any age, but their presence increases in prevalence with increasing age. Immunity compromised patients such as diabetics, patients on long-term corticosteroids or chemotherapy, or patients who have HIV/AIDS also have increased risk and prevalence of Demodex infection. Usually, when the immune system is weakened and the parasitic population has colonized, this disease can badly damage the skin.
 

How Can Demodex be Transmitted?

For transmission of mites from one person to another, direct contact of hair and sebaceous glands on the nose, or dust containing eggs is required. Since the disease processes begin when there is an overpopulation of Demodex, the vast majority of cases of mites go unobserved and don't show any adverse symptoms. However, in certain cases, the mite populations migrate and multiply in the eyelashes.
 

What Are The Types of Demodex?

There are two existing types of Demodex mites: the longer kind, Demodex folliculorum, which live in the hair follicles and the short ones, Demodex brevis, which live in the sebaceous (oil) glands in the skin.
 

What Are The Symptoms of Demodex?

In the early stages, there are often no noticeable symptoms, but if left untreated Demodex can progress. Symptoms vary among patients and may include dry eye, red eyes, severe itching along the eyelid margin and eyebrow, especially in the morning, eyelid irritation, burning sensation, foreign body sensation that seems to originate beneath the eyelids, heavy lid, and blurry vision. One of the earliest signs of mite infestation is cylindrical dandruff (CD), which is the accumulation of fine, waxy, dry debris that collects at the base of the lash and extends up to 2 mm along the length of the lashes and is most noticeable on the upper lashes.