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Tonometer

A tonometer refers to the equipment that is used in tonometry – a test that measures the pressure inside your eyes, also known as intraocular pressure or IOP for short. Tonometry is rarely performed at your average comprehensive eye exam unless you are at high risk of or have been already diagnosed with glaucoma. Fortunately, tonometry can be used to detect changes in eye pressure before they cause any symptoms, enabling prompt action to be taken before your vision is affected.


About Glaucoma

Glaucoma is a common eye condition that occurs when the optic nerve, which connects the eye to the brain, becomes damaged. It’s normally caused by fluid building up in the front part of the eye, which causes the pressure inside the eyes to build. As the pressure increases, the optic nerve becomes increasingly damaged, and this prevents messages from being transmitted between your eyes and brain effectively. As a result, the patient’s vision becomes compromised. Without treatment, the level of vision loss will continue to increase. Unfortunately, any vision that has been lost as a result of glaucoma cannot be restored.
 

Most of the time, glaucoma develops very slowly which means that many people don’t realize that they are affected until some damage to their vision has already occurred. However, occasionally glaucoma can develop quickly, and symptoms do occur.

These can include:

  • Red eyes

  • Intense headaches

  • Tenderness around the eyes

  • Eye pain

  • Seeing rings/halos around lights

  • Blurred vision

  • Nausea and vomiting


If you notice any of these symptoms, it’s important that you make an appointment with your eye doctor right away so that you can be assessed. You are likely to have a tonometry test as part of this assessment.
 

What to expect from tonometry testing

There are various methods of tonometry testing, but many eye doctors use either Goldmann tonometry, which is the conventional technique to measure eye pressure, or electronic tonometry.
 

Goldmann tonometry testing is carried out using the Goldmann applanation tonometer, which is attached to a slit lamp microscope. This requires anesthetic eye drops to be used which numb your eyes, before a small probe is pressed gently against the eye, indenting the cornea. The pressure that the cornea pushes back onto the tonometer is what is measured to give your IOP reading. Electronic tonometry is where a handheld, mobile device is gently and quickly applied to the cornea to check the pressure, providing an accurate reading. Some eye doctors also offer non-contact tonometry which is where a puff of air is used to flatten the cornea, although this is reported to be less accurate than the Goldmann technique.
 

If you would like to find out more about Tonometry testing, please call our office to speak with our dedicated eyecare professionals.


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.


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.
 


LASIK Procedure

If you are one of the thousands of people considering LASIK laser eye surgery, then you will probably be gathering as much information as possible about the treatment. By this point, you are probably aware of the benefits that LASIK offers, such as a reduced or eliminated need for glasses or contact lenses and greater convenience in your day to day life. However, for many patients, despite the advantages of LASIK, the thought of surgery on their eyes is still a cause of anxiety and fear. One of the best ways to alleviate this concern is to find out more about what the procedure entails.
 

Your consultation

Before you can be approved for any form of laser vision correction, including LASIK, you will need to attend a consultation appointment with your surgeon. During the consultation, he will perform an examination of your eyes and use your medical and ocular history to determine if you are a good candidate for the procedure. He will also speak to you about the expected outcome from your surgery, making you aware that while LASIK will dramatically improve your eyesight, there is no guarantee that you will not need to wear glasses in some situations, such as while driving in the dark. 
 

How LASIK Works

LASIK uses a cool, ultraviolet beam of light to reshape the patient’s cornea. Doing so will more accurately focus the light that enters the eye on to the retina, thus improving the patient’s vision. The way in which the cornea needs to be reshaped will depend on the visual needs of the patient. For example, a patient who is far-sighted will need their cornea reshaping to be steeper to experience better eyesight. Alternatively, a patient who is near-sighted will require their cornea to be flattened in order to improve their vision. LASIK can also smooth an irregular cornea into a more standard shape, meaning that the procedure can also be used to correct astigmatism.
 

The LASIK procedure

The LASIK procedure is very fast and straightforward. Although you will probably be in the surgical suite for around half an hour, the actual process only takes a couple of minutes per eye. The rest of the time will be spent preparing and ensuring that you are comfortable. Anesthetic eye drops are given to patients before their procedure so that the entire process is pain-free. If you are particularly anxious, it may also be possible for you to be slightly sedated – this should be discussed with your doctor at your consultation appointment.

Once you are in position, we will use a femtosecond laser to cut a thin, circular flap into the outer cornea. This can then be pulled back to reveal the underlying corneal tissue, known as the stroma so that it can be reshaped using the laser. The exact path that the laser needs to take, known as the topography, will have been pre-programmed ahead of the procedure and can be followed with complete precision and accuracy.

Once the reshaping is complete, the flap is replaced back over the eye and the surgery is complete. There is no need for sutures or bandages as the cornea will start to heal immediately and without any medical intervention.
 


Am I a candidate for LASIK?

If you already rely on wearing glasses or contact lenses to be able to see clearly, you may be frustrated with the effect that they have on your life. Regular vision tests, finding glasses to suit your face shape, having to remember to take eyeglasses with you wherever you go, prescription sunglasses, fiddly contact lenses… the list of inconveniences associated with conventional ocular solutions is extensive. 

LASIK is a modern, minimally-invasive procedure that can substantially reduce or eliminate your need to use eyeglasses or contact lenses, allowing you to enjoy life without limitations or inconvenience. The popularity and success of LASIK laser eye surgery have helped to make it the number one elective surgery across the globe. 
 

Candidacy for LASIK

LASIK has an extremely high success rate. According to the American Society of Cataract and Refractive Surgery, 96% of patients achieve 20/20 vision or better. However, it’s high success rate doesn’t make LASIK automatically the right solution for everyone.

Candidacy for LASIK is assessed by our doctors on a case by case basis so that you be certain that whatever treatment is recommended for you, it will give you the very best opportunity to improve your vision. During your consultation, our doctors will perform a thorough examination of your eyes and vision, ask you about your general health and talk you through both the procedure and aftercare.

The general guidelines for LASIK candidacy state that patients must:

  • be at least 18 years of age

  • have had stable vision with no prescription changes for a minimum of 12 months

  • have a current prescription for eyeglasses or contact lenses that falls between specified parameters (Our doctors will be aware of what these parameters are)

  • have no significant medical or eye-related problems such as glaucoma, macular degeneration or diabetic retinopathy

  • have no history of corneal disease

  • not be pregnant or nursing at the time of the procedure


iDesign Custom Lasik

If you thought that just laser eye surgery was impressive, then be prepared to be astounded by the arrival of iDesign custom Lasik. iDesign is the most advanced wavefront-guided laser treatment available. The system creates a uniquely accurate measurement of the entire optical system that can be relied upon completely without any guesswork. This is then used to create a highly detailed topography or map of your eye, making it easier for your surgeon to pinpoint the areas that need addressing with pinpoint precision. 
 

How accurate is iDesign?

iDesign is extremely accurate due to its diagnostic equipment that is able to determine 1,257 different micro eye prescriptions. Each one of these will measure the eye prescription to 0.01 of a dioptre strength – 25 times more than what a regular prescription for glasses or contact lens prescription is measured to. 
 

Who is iDesign suitable for?

While iDesign Custom Lasik can benefit almost any patient with refractive problems, it is particularly beneficial for people who have unusual corneas or have had eye surgery in the past. 
 

Is it painful?

Laser eye surgery is generally considered a pain-free procedure by the majority of patients. Anesthetic eye-drops are used to numb the outer area of the eye during the course of the surgery. Once these have worn off, some patients do experience some mild discomfort during the days following the procedure, but over the counter pain relief is usually sufficient to relieve this.
 


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.