Eye Disorders & Treatments
Click a letter below to learn more about the types of eye disorders we treat.
Accommodative Excess refers to the tendency to focus closer in than the page being read, ie the individual will focus as if the book is closer than it really is.
This is commonly found in cases of Convergence Insufficiency, where the individual has difficulty aiming the eyes at near at the same place on the page, by overfocusing the eyes are able to be brought together to the one point.
Accommodative Excess however reduces visual stamina and can affect binocular vision.
In school aged children this is of concern as it both reduces visual efficiency but also delays ability to shift focus between distance and near tasks.
It is common in these cases for symptoms of headaches and/or sore eyes to be reported.
In cases of Accommodative Excess, there is often the report of transient blur in the distance when looking up after doing near tasks such as reading.
The risk factor is myopia (shortsightedness) being induced later in life, often in the teenage years, should accommodative excess be allowed to continue.
Treatment is the use of a Therapuetic spectacle lens prescription, this usually prescribed as a multifocal lens. The concept being to utilise the bottom section of the lens to improve near binocular vision levels whilst still allowing clear distance vision through the top of the lens, this being especially important at school and university.
Also in some cases Vision Therapy may be indicated to retrain the visual system to operate in a more efficient manner.
Accommodative Insufficiency refers to a reduced level of focus stamina required for accurate near binocular vision.
This is often associated with a Convergence Excess, reduced levels of accommodation often requiring the individual to aim the eyes closer in than the page they are reading in an effort to increase focus strength.
Insufficient accommodation usually results from either delayed vision development in children, or in situations of visual stress in adolescents and adults.
Treatment for accommodative insufficiency is best addressed by use of Therapuetic Spectacle lenses. These are generally prescribed in a multifocal form to allow improved near vision accuracy whilst not disturbing distance vision, this being especially important in school children so they may shift focus with ease and clarity between board and page in class.
Accommodative Insufficiency can reduce visual attention levels and visual memory abilities as the child is required to direct more attention to keeping clear vision, thereby reducing available concentration required for processing the visual information.
Often stamina and ability to concentrate in class or at work is affected, and the individual finds it difficult to keep focus on the page, often looking away or daydreaming. It is common to find these individuals having to re-read sentences over again for comprehension.
The Behavioural Optometrist is able to accurately assess levels of accommodation and prescribe appropriate treatment should this be required.
Amblyopia, or lazy eye, is poor vision in an eye that failed to develop normal vision during early childhood.
It affects around 2 to 3 percent of people. Someone with amblyopia usually has good vision in one eye, although it is possible for amblyopia to develop in both eyes.
Any condition that impedes the normal development of vision in an eye can cause amblyopia, however the two most likely causes are:
- Strabismus (misaligned or crossed eyes) – A misaligned or crossed eye will eventually turn-off to avoid double vision occurring. This will prevent vision from developing normally and amblyopia will result.
- Unequal Focusing – Amblyopia can occur in an eye that has poorer focusing than the other eye due to refractive error. This can be difficult to detect as there is no visible symptom like in the case of a crossed eye.
- Non-refractive Amblyopia – May occur in the absence of poor focusing or an eye turn yet one or both of the eyes may have blurred vision. This is commonly associated with some form of congenital developmental delay, or may be associated with an eye injury or brain injury.
Amblyopia may also develop in an eye that has become cloudy in the areas of tissue that are normally clear. An example of that is Cataracts.
Where a child has high levels of long sightedness, shortsightedness or astigmatism, amblyopia may develop in both eyes.
Because amblyopia is not easily detectable in infants, a routine eye examination by an optometrist is recommended for all small children. The earlier amblyopia is diagnosed, the more effective the treatment will be.
Ideally, treatment for amblyopia should begin in infancy or early childhood.
Amblyopia is treated by wearing glasses to improve the vision in the poor eye, thus allowing the vision to develop normally. In some cases the good eye may be blurred with the use of glasses or a patch to encourage the poorer eye to work. Vision Therapy is often very effective in the treatment of amblyopia, this involves a customised program of activities conducted both in-office and at home in order to stimulate the visual system and enhance binocular vision ability.
Success in treating amblyopia depends on how severe it is and how early it’s detected. Early detection and treatment of amblyopia will mostly result in improved vision.
Anisometropia is a significant imbalance in refractive error between the eyes.
That is one of the eyes requires a significantly stronger corrective prescription in order to see clearly.
This is commonly found in Refractive Amblyopia, ie where one of the eyes is either not used fully compared to the other eye due to an excessively high prescription, or where one of the eyes appears initially to not function correctly.
Treatment for anisometropia is usually the corrective spectacle prescription to give maximal visual acuity for each eye. This is important to reduce the risk of Amblyopia in cases of untreated anisometropia. Vision Therapy may be useful in treating the effects of anisometropia.
Astigmatism results when the shape of the cornea (the clear section of the eye covering the iris) is not spherical; in other words, when the cornea is shaped more like the back of a dessert spoon rather than the back of a soup spoon. It may also exist, although less commonly, because of an irregular shaped lens within the eye.
Astigmatism is not a disease; it is merely a variation in the shape of the cornea or lens and is very common. It should be noted that in cases of continual progression of astigmatism, there is a need to exclude Keratoconus, which is a disease of the collagen fibres of the cornea, often genetic, that allows progression of a cone shaped cornea. This is best measured using a Corneal Topographer, which is available at Vision West, and treated using Rigid Gas Permeable Contact Lenses.
Moderate to large amounts of astigmatism will cause images to appear misshapen and blurry at any distance.
The usual way of correcting astigmatism is by wearing glasses or contact lenses. Most long sighted, short sighted and presbyopic people will also have small amounts of astigmatism which the optometrist will account for in a spectacle correction.
In children it is possible to measure a type of astigmatism that is actually secondary to focusing conditions, ie the eye shape may be correct but astigmatism is measured. This is best treated using behavioural optometry techniques including therapeutic spectacles and/or Vision Therapy.
There also exists lenticular astigmatism where the lens shape is irregular, again causing distortion of incident light.
Incorporates all aspects of primary vision care. Behavioural Optometrists examine all age ranges of patients from infants, school aged children through to adults of all ages.
Behavioural optometry incorporates regular vision care with vision development assessments. That is, there are many children who can see but do so inefficiently and, even though able to read an eye chart, the effort required cannot be readily sustained, affecting not only vision development but also ability to concentrate and listen in the classroom.
Sometimes referred to as Developmental Optometry, this term can be limiting in its definition as it implies to many people that Behavioural Optometrists will only see children.
Nothing could be further from the truth, the term Behavioural Optometry is therefore more accurate as it infers that Visual Efficiency or Visual Processing issues can influence a person’s behaviour, be it headaches, sore eyes, blurred vision, trouble concentrating in the classroom or office, blur after working on the computer, watery eyes, eyestrain, red/sore eyes etc… and this regardless of a person’s age.
A cataract is a cloudiness that develops in the normally clear lens in the eye. The effects of cataracts can best be explained as similar to looking through a misty window. Over time a cataract will become denser and denser until it occludes vision altogether.
There are several causes of cataracts, the most common being associated with ageing (Age Related Cataracts). Although cataracts don’t usually start to affect most Australians until they are in their 60’s or 70’s, an earlier onset of cataracts can be attributed to smoking, excessive exposure to sunlight, diabetes, and the long term use of some medications (Secondary Cataracts). Cataracts may also develop after an eye injury (Traumatic Cataracts) and in rare cases babies are born with cataracts or develop them in early childhood (Congenital Cataracts).
As cataracts usually develop slowly over a long period of time, most people only become aware they have them following a routine visit to the optometrist or ophthalmologist. Someone with cataracts may need to have several prescription updates over a shorter than normal period of time.
Common symptoms of cataracts are:
- Cloudy or blurred vision at any viewing distance
- Glare sensitivity
- Haloes around lights at night time
- Colours looked washed-out
Cataracts are treated by way of a surgical procedure performed by an ophthalmologist in a hospital or day surgery. Sophisticated equipment assists the ophthalmologist to perform suture-less surgery that removes the cataract portion of the lens, which is then replaced with an artificial prosthetic lens.
Prior to the surgery, measurements are taken and calculations are made to ascertain the type of prosthesis that will be used to deliver as close as possible to clear distance vision without the need for glasses. Some pre existing conditions such as astigmatism may not be fully corrected during the surgery and glasses may still need to be prescribed. In most cases reading glasses will be needed after cataract surgery, and in many cases multifocal spectacles are still the ideal option for practicality.
Convergence Excess occurs where the natural posture of the eyes is closer in than required for near vision tasks.
Convergence excess means the individual, when they look to near vision tasks, has a natural tendency to aim the eyes closer in than the position they are trying to aim at.
For example someone reading would ideally aim and focus the eyes together on the words on the page, in cases of convergence excess there is usually the situation where the eyes meet to aim at a point closer in than the page.
Often individuals can be noted to work closer to the page when this occurs.
This excess of vergence is commonly associated with an Accommodative Insufficiency. The eyes are aimed closer in than desired in an attempt to compensate for reduced focus stamina or focus ability.
This leads to a mismatch between vergence and focus, thus affecting binocular vision accuracy.
Management of convergence excess requires therapeutic spectacle prescription lenses to enhance the focus efficiency thus reducing the need to pull the eyes closer in.
This is a therapeutic treatment that requires monitoring over time to ensure the excessive demand is reduced to within a normal range of focus and convergence.
Usually over time prescriptions can be reduced and wearing time reduced.
Without effective management, myopia (shortsightedness) can often result in later years, such as in high school.
Convergence Insufficiency is a reduced ability to bring the eyes together for near vision tasks.
In order to read and focus at near, the visual system is required to make a single clear image by bringing the eyes closer together, this usually being stimulated when a person looks down and close. If this does not occur then a blurred double image would be the result, or the brain would switch one eye off to cope, this is termed Suppression or Amblyopia.
In many cases the reduced ability to bring the eyes together for near vision tasks is related to focus insufficiency. That is, many children have reduced convergence being linked to inefficient focus for near vision affecting awareness of where to aim the eyes, this due to developmental delay in their focus stamina.
In cases of focus issues being linked to the convergence insufficiency, therapeutic spectacle lenses are often all that is required to improve both the focus delay and convergence ability.
These Therapeutic spectacle prescriptions are most commonly dispensed in multifocal form, so that assistance may be given for near vision without disturbing distance vision. This is necessary in a classroom situation for children or office situation for an adult so as to allow smooth transition of focus between distance and near tasks.
Usually single vision lenses, although beneficial for near, become problematic in the distance as the individual is then looking through a prescription they do not require when trying to look at the blackboard. So benefit at near can be negated by the distance blur, leading to further eyestrain and compliance issues.
In cases of convergence insufficiency which are more related to the ability of the visual system to turn the eyes inward then a program of Vision Therapy may be required to retrain the eye muscles to converge. This is usually due to a developmental delay in the flexibility, co-ordination and integration of the eye muscles that move the eyes in whichever direction we are to be looking.
In more longterm cases of convergence insufficiency, it is common to find an Exotropia also being present, where one eye fixates and the other remains slightly divergent, ie an outward eye turn.
Often a combination of Vision Therapy and Therapeutic Spectacle Prescriptions are required to manage cases of Convergence Insufficiency.
Diplopia (Double Vision)
Diplopia or double vision can be the most frustrating of all eye conditions. The most common form of diplopia (binocular diplopia) arises when the eyes are misaligned and the symptoms may be constant or intermittent.
The affects of binocular diplopia will cause images to appear vertically, horizontally or diagonally double due to misalignment or imbalance in the actions of each of the eye muscles that control movement of each eyeball.
Examination is required to exclude pathology as a possible reason for loss of binocular vision.
In many cases the onset of diplopia can be due to age as the loss of accuracy and flexibility in the muscles may be one of the reasons for double vision.
Other reasons for diplopia include head injuries or secondary to other illnesses, so examination is very important if double vision is noticed either binocularly or even if just in one eye, ie monocular diplopia.
Divergence Insufficiency is associated with an Esotropia. In this case the inward eye turn is greater at distance than at near.
Management involves a program of Vision Therapy and may also require spectacles to try and control the deviation, ie to assist the eyes in working together and looking straight.
Esotropia is an inward eye turn of the eyes when looking at distance, near or both. The eyes adopt what is more commonly known as a ‘cross-eyed’ appearance.
This may be congenital from birth or acquired in the early years of life, often prior to commencement of primary school.
Most commonly seen in association with an Accommodative dysfunction, the esotropic child will usually have a high degree of Hyperopia (longsightedness) associated. As the individual focuses excessively to control the hyperopia, eventually when control is lost on or both the eyes may turn inwards.
This is sometimes constant but more commonly intermittent, ie occurs when looking in certain directions or when tired or when viewing new things such as when starting pre-school.
In an Accommodative Esotropia, treatment often only requires early intervention with full time spectacle wear. If the eyes are kept in the straight position by the spectacle correction then chances of Amblyopia are reduced, but not eliminated altogether.
It is common for spectacle prescriptions in the early stages of treatment to increase rapidly, this can be alarming for the parents but it is necessary to keep the prescription at its optimal correction to allow the best chance of binocular vision later in life.
Commonly a prescription will increase during childhood often to moderate or even reduce later in the teenage years.
The most common observation by parents of children with an accommodative esotropia is that they may have not noticed, or only rarely noticed, the eye turn in their child prior to getting spectacles. Yet since having the glasses they have noted the eye turn increase when the spectacles are taken off, reassurance is given that this is a normal occurrence.
As the visual system utilises the spectacle correction to keep the eyes straight until later in life often the eye turn will increase without the spectacles. This does not mean the spectacles are ‘ruining’ your child’s eyes, rather it is a confirmation that without adequate spectacle correction the eye turn may be even greater or the incidence of Amblyopia far more likely.
Vision Therapy is commonly required to help train the child to use their eyes together in a more efficient manner.
Exotropia is a divergent or outward eye turn that may be present at distance or near or both.
This may or may not have in association with it a Convergence Insufficiency.
Often present from the early stages of development, the outward eye turn is usually intermittent and may benefit from management by spectacles or Vision Therapy or a combination of both.
As in all cases of Strabismus early intervention and management is essential in order to reduce risk of compensatory measures by the brain such as Amblyopia.
Glaucoma describes damage to the optic nerve and retina that is most commonly caused by a higher than normal build-up of pressure in the eye.
It is essential for the eyes to maintain a constant and firm shape for light to focus accurately within them. The body does this by pumping a clear fluid called aqueous into the eye, which also provides the eye with essential nutrients from the blood. The aqueous drains in and out of the eye against a resistance which sustains a pressure that is higher than air but lower than blood pressure.
Damage through higher than normal pressure can result if there is a blockage in the circulation or drainage of aqueous fluid.
Damage may also be caused by poor blood supply to the optic nerve fibres, a weakness in the structure of the nerve, or a problem in the health of the nerve fibres.
During a routine eye examination your optometrist will test for glaucoma by measuring the pressure within the eye as well as examining the optic nerve at the back of the eye. If any abnormality is detected or if there is a family history of glaucoma, your optometrist will perform a visual field check to further rule out the possibility of glaucoma. A visual field allows the optometrist to assess for loss of sensitivity to light or even a loss of sight in parts of the retina, this usually commencing in the peripheral vision in glaucoma.
As the peripheral vision is often the first to be affected by elevated eye pressure, there is generally no symptoms for an individual in the early stages of the most common form of glaucoma, which is why monitoring of intraocular pressure is very important, generally being checked every two years in persons over 40 years of age, or annually if there exists a family history of glaucoma or if previous tests have been suspicious.
Should an elevated eye pressure or visual field loss be detected the optometrist will refer to an Ophthalmologist for treatment.
Glaucoma is controlled most commonly by the use of eye drops which help to maintain an acceptable pressure in the eye. More acute forms of glaucoma may be treated by laser surgery.
As the name suggests, people that are longsighted generally cope better with long distance vision than near vision. However, being long-sighted doesn’t mean your long distance vision will always be clear and near vision always blurry, this will depend on the amount of hyperopia and your age.
Hyperopia results when light focuses beyond the retina at the back of the eye. The most likely causes are the length of the eye being too short, and generally in children when there exists a delay in the focus system stamina being developed.
About 25% of Australians are Hyperopic. It is normal for a child to have a low level of longsightedness up to the end of the primary school years.
The symptoms for low and moderate amounts of hyperopia are blurred or strained vision at near, however hyperopia is sometimes confused for presbyopia (age related near vision loss). Higher degrees of hyperopia will cause vision to blur in all viewing areas.
The eyes near focusing mechanism (accommodation) may neutralise the blurring affects of hyperopia in younger aged people. For this reason, hyperopia is commonly not detected during routine vision screenings at schools etc. A comprehensive eye examination by an optometrist will detect hyperopia, and more specifically the Behavioural Optometrist will fully assess age appropriate focus stamina and near binocular vision levels that can be affected by the longsightedness.
Hyperopia is commonly corrected by wearing glasses fitted with convex or plus lenses or by wearing contact lenses.
A progressive condition where the cornea becomes more oval shaped, eventually forming a corneal cone distortion over time. The cause of this condition is not fully understood however is often hereditary and is believed to have a link with persons who eye rub excessively due to allergies or itchy eyes.
Keratoconic persons are usually not able to see clearly through spectacles due to the distortion in the cornea and are best managed by fitting of Rigid Gas Permeable Contact Lenses, often requiring a specific type of hard lens to accommodate the irregular shape of the eye.
The fitting of these hard lenses not only improves visual acuity but also has been shown to reduce progression of the cone formation in keratoconic eyes. Soft contact lenses cannot usually achieve similar levels of visual acuity due to the fact they ‘wrap’ over the cone shape of the eye and therefore distort vision in the same way as spectacles.
Experimental medical treatments incorporating use of specific eye drops to try and reduce progression of keratoconus are currently undergoing research and trials in Australia.
Progression beyond fitment of contact lenses is not common, however in cases where this occurs referral to an Ophthalmologist for consideration of corneal grafts is a worst case scenario.
Macula degeneration mostly occurs as a person ages but can occur in two different forms and for different reasons. There is the dry form which involves spots on the retina appearing known as drusen, these spots are debris that build up on the retina with age and can reduce vision. In the wet form new blood vessels form at the macula and cause haemorrhaging and scarring again reducing vision. There are many contributing factors to macula degeneration risk, these include excessive UV exposure, smoking, poor diet and ageing. It is recommended that sunglasses be worn to protect the macula and that our diets should include a healthy dose of antioxidants and omega 3 such as we can find in leafy green vegetables and fish.
The terms short, or near sightedness, are used when the condition myopia exists, which is the ability to have clear vision close-up but not in the distance.
Around 20 -25 percent of Australians are myopic.
People with low amounts of myopia may only need to wear glasses when driving at night and at the movies, while higher amounts of myopia may require glasses to be worn even when reading.
Myopia occurs when light focuses short of the retina at the back of the eye. This is usually because the eye is too long.
People with moderate or low amounts of myopia will find themselves removing their glasses to read once they acquire presbyopia in their mid forties.
Myopia is corrected by wearing glasses fitted with concave or minus lenses, contact lenses or by undertaking refractive surgery.
The most common type of myopia (physiological myopia) develops in childhood and generally continues to increase until the eye is fully grown. The number people in the population with this type of myopia have dramatically increased around the world over the last 50 years and as a result, several new theories on why eyes become myopic are now being debated.
For myopic children, generally multifocal spectacles are fitted to best allow distance and near visual accuracy in the classroom ie so that the distance prescription does not excessively strain the child’s eyes when reading.
In the early stages of myopia or for low to moderate myopia it is possible to undergo Orthokeratology contact lens fitting, which involves wearing contact lenses at night to allow vision unaided during the day.
Some research suggests that Orthokeratology may reduce progression of myopia. This has also been thought to be true, to a lesser extent, with daytime Rigid gas permeable contact lenses.
Other forms of hard and soft contact lenses can be fitted to allow clear vision during the day.
Non-refractive Esotropia is where the inward eye turn exists but is not associated with a high degree of longsightedness. In these cases Vision Therapy would again be recommended to attempt to retrain the co-ordination of the eyes.
In some extreme cases of high degrees of eye turn that are not treatable by either spectacles nor Vision Therapy, then referral to a Paediatric Ophthalmologist may be indicated to assess suitability for corrective eye muscle surgery.
It is recommended that in these cases that post surgery Vision Therapy is conducted by a Behavioural Optometrist in order to teach the child how to reuse their ‘new’ visual system.
Optometric Phototherapy (Syntonics)
Optometric Phototherapy (or Syntonics) is one component of Vision Therapy offered at Vision West.
Syntonics is the use of specific frequencies (colours) of visible light projected into the eyes, to enhance visual efficiency (focus/eye movements) and visual information processing (interpreting what is being seen).
It is used within a program of Vision Therapy, the word Syntonics is defined as ‘balance’, which implies this procedure is a form of vision therapy being utilised to enhance the balance within the visual system.
Assessment involves measuring the visual fields. This is measured prior to Syntonics using a specialised instrument called a Stereo Campimeter, which allows measurement of the ability to perceive the expanse of visual space within which someone can detect not only movement but also different colours.
In cases of visual fatigue and visually related learning difficulties, an individual’s perceptual visual fields may become temporarily constricted. For example if there exists difficulty maintaining focus or binocular vision for reading it is possible that a person may only see a few letters at a time on the page, rather than being able to scan across the lines of words in the text being read.
If visual stress is influencing the volume of visual information that can be processed per eye movement then Syntonics may be beneficial in improving the visual information processing.
Common situations where this can be an issue include the visual skills required for reading and in the classroom environment, with words often moving, merging or ghosting on the page and children possibly skipping lines or words as they find it difficult to locate their eyes accurately.
Constricted perceptual visual fields can also affect visual-spatial awareness, the ability to perceive and judge where objects are in one’s visual space, an important skill for organising work on the page when writing and also for balance and co-ordination such as in movement and sport.
Syntonics usually involves home based therapy which is reviewed in-office. In most case, the therapy would involve hiring a Syntoniser (light unit) along with the specific and individually prescribed coloured filters required. The filter is placed in the Syntoniser and the prescribed coloured light viewed in a dark room, usually for twenty minutes per day for an average period of four weeks.
There are most commonly one or two differently coloured filters required.
Common visual conditions where Optometric Phototherapy may be beneficial include:
- Visually Related Learning Problems
- Focus and eye movement difficulties
- Binocular Vision difficulties
- Photophobia (glare sensitivity)
- Acquired Brain Injury
- Sports Vision
Orthokeratology more commonly referred to as ‘Ortho-K’, the use of contact lenses to reshape the cornea (front surface of the eyes) in order to reduce levels of myopia and astigmatism. The lenses are worn in the evening whilst sleeping and allow clear vision for the next day once removed upon waking.
Presbyopia (age related near vision loss)
Presbyopia develops during middle age causing vision to blur at near. The effects of presbyopia are usually felt around 44 years of age, but that will vary depending on whether there are other pre existing eye conditions and what visual demands the eyes are normally under each day.
Although the onset of presbyopia is relatively slow, once the effects are noticed it can seem as if the condition has suddenly developed and this occasionally creates anxiety. What has actually happened is the protein fibres in the lenses of the eyes have changed over time, making them harder and less elastic, such that the lens cannot as readily change shape when required to alter focus between varying distances. This change reduces the amount of near focussing that was once achievable. Everyone will eventually experience presbyopia.
The most common way presbyopia is corrected is by wearing glasses.
As modern visual demands such as using a computer require more than one focusing point in a pair of glasses, single vision lenses are no longer the best option for correcting presbyopia. Extended focus lenses, which provide a full reading prescription in the bottom half of the lenses and a weakened prescription at the top (for viewing a monitor), provide a preferred solution.
Another option for people with presbyopia is to use progressive addition lenses (PALs), otherwise known as Multifocals. They provide distance, intermediate and near vision in one set of lenses. PALs may be the perfect solution for someone that requires a distance prescription also, or for people with good distance vision but have a constant requirement for clear distant and near vision throughout their working day.
PALs may not be the most appropriate option for someone using a computer for extended periods of time; this is because, in a workplace monitors often sit too high for viewing comfortably through the intermediate or near sections of the progressive addition lens. In this situation the only way to achieve clear vision for all situations would be to have two pairs of glasses; one fitted with PALs for general use and another with extended focus lenses which could be left by the computer.
Contact lenses may also provide a solution for someone with presbyopia. Although there are contact lenses available for correcting Presbyopia, there is a trade off in clarity of vision when using them. Another option is using contact lenses to correct distance vision in one eye and near vision in the other (mono vision).
Correcting the effects of presbyopia through refractive eye surgery is also possible, however the outcome and options are similar to those presented with contact lenses. For this reason, surgery is rarely prescribed as a typical option for people with presbyopia.
Rigid Gas Permeable Contact Lenses
Otherwise known as Hard contact lenses, these are generally safer and healthier to wear than soft contact lenses due to the increased oxygen flow to the eye and the superior materials they are made of.
Although commonly people are hesitant (due to the fear of the word ‘hard’ thinking this implies discomfort) to pursue fitting of hard lenses when recommended to them, the end result is usually healthier eyes and more stable vision that can be maintained for longer wearing times than many soft lens options.
Well maintained hard contact lenses will not usually show long term effects on the cornea as opposed to the higher risks of contamination associated with many types of soft contact lenses.
Strabismus is the term used to describe an eye turn. Please see further specific information under the headings Exotropia and Esotropia.
Suppression is where one eye is used in preference to the weaker eye, ie the brain may constantly or intermittently shut down visual input from one eye in situations where binocular vision cannot be readily achieved. This commonly is found in conditions of Amblyopia, Strabismus (Esotropia or Exotropia), Anisometropia.
Therapeutic spectacle lenses are most often used by school aged children, university students or people working in offices that are measured to have a degree of visual stress or inefficiency.
These lenses are not to be confused with compensating lenses which are typically what people think of when they think ‘glasses’.
That is, compensating lenses reduce blur whereas therapeutic spectacle lenses are used to reduce symptoms such as sore eyes or headaches or intermittent blur that may result from visual inefficiency conditions such as convergence excess, convergence insufficiency, accommodative excess or accommodative insufficiency.
The most effect means of prescribing involves a type of multifocal lens, this allowing the therapeutic benefit at near to be achieved whilst not interrupting a person’s distance vision. It is important that children usually be prescribed this type of lens to best function in the classroom.
Vision Therapy involves the use of lenses, prisms and activities to improve visual efficiency and Visual Processing skills including eye teaming, focus and visualisation skills.
Vision Therapy is also prescribed to enhance and improve awareness/ability of both Visual Efficiency and Visual Processing skills.
Most Learning Difficulty children have both a Visual Efficiency and Visual Processing issue, in isolation treatment of one condition is not always successful.
The treatment involves a complete initial optometric assessment to evaluate an individual’s vision and ocular health status. Following this, if recommended, further assessment to ascertain whether Vision Therapy may be beneficial is conducted.
Vision Therapy, the optometric modality of developing and enhancing visual abilities and remediating vision dysfunction, has a firm foundation in vision science.
At Vision West, following initial optometric assessment, if Vision Therapy is deemed suitable, then a customised one-on-one program is designed for the patient.
This Vision Therapy program typically involves attending on a weekly basis for approximately forty five minutes with our Accredited ACBO Vision Therapist for in-office sessions. These are combined with home based activities that are done for twenty minutes per day.
The aim of the Vision Therapy program is to enhance both the visual efficiency skills such as focusing and eye movements/eye teaming/binocular vision as well as the ability to accurately and rapidly process visual information and retain this information in one’s visual memory for later correct recall.
The Vision Therapy program will usually span over a three to four month period.
Refers to the ability and stamina of the visual system regarding focus, eye movements and binocular vision levels. In cases of reduced visual efficiency the result may be headaches, sore eyes, blurred vision or difficulty in concentrating. Best treated using therapeutic spectacles, and in some cases, enhanced using Vision Therapy.
Visual Information Processing
The ability to process incoming visual information. This refers to a person’s ability to give meaning to what is being seen, such as comprehending what is being read from the page, or what is occurring around us in one’s environment.
Reduced visual perceptual skills can affect learning in terms of visual memory, visual recall and visual attention.
Visual Information Processing skills can be enhanced by the use of Vision Therapy.
Also known as Visual Information Processing, is the ability to give meaning to what is being seen. Good visual perception means being able to quickly and accurately process and analyse what is being seen, and store it in visual memory for later recall. This is important in being able to decide what appropriate action is required to interact with the environment and circumstances to which an individual is exposed. For example, in the classroom when reading and writing it is important to be able to quickly and accurately decode, comprehend and remember written material whilst still being able to listen to the teacher.
Individuals with reduced visual information processing ability often require Vision Therapy to improve visual perceptual skills, i.e. the ability to rapidly and accurately process visual information received with each eye movement, and to then store this information in correct sequence for later accurate recall.