Why choose iSIGHT?
With so many options available to you, you can trust us to look after one of your most precious possessions… your eyesight.
Since 1993 we have helped thousands of people improve their vision. We appreciate that you have certain expectations of what private eye care should be and we continue in our pursuit of exceeding those expectations. As a specialist, consultant-led practice, your eyesight is our sole focus and passion and we are proud of the reputation of excellence and the strong patient relationships that we have built up over the last 23 years.
What to expect…
Our practice is based in Southport in a beautiful grade II listed building. Upon arrival, our dedicated and welcoming team will strive to make your visit as relaxing and comfortable as possible. You will be shown to our Private Patients drawing room where you will be offered light refreshments.
A member of our medical team will then come and introduce themselves to you, take you through the process and answer any questions or concerns you may have.
Additional Patient Information
- If you are covered for medical insurance please contact your insurance company and obtain a pre-authorisation number and bring this to your appointment.
- If you're not covered for certain parts of the treatment, a member of our finance team can help you with this process by calling 01704 552212
Do I Need a GP/Optometrist Referral?
- Usually yes. A letter of referral from your own GP is needed. It is good medical practice and allows us to get a complete picture of any relevant underlying health issues.
What Should I Bring To My First Consultation?
- A list of your current medication
- Your current glasses and prescription
- A letter of referral
- A companion if necessary (for example if your pupils are being dilated)
- If you do not have medical insurance please ring reception directly on 01704 552218 to book an appointment.
- Alternatively, see our contacts page for further details.
Do I Need a GP/Optometrist Referral?
- Usually yes. A letter of referral from your own GP is needed. It is good medical practice and allows us to get a complete picture of any relevant underlying health issues.
What Should I Bring To My First Consultation?
- A list of your current medication
- Your current glasses and prescription
- A letter of referral
- A companion if necessary (for example if your pupils are being dilated)
Why are regular sight tests so important?It's easy to neglect your eyes because they rarely hurt when there's a problem. Having an eye test won't just tell you if you need new glasses or a change of prescription, it's also an important eye health check. It can spot many general health problems and early signs of eye conditions before you're aware of any symptoms – many of which can be treated if found early enough.
How often should I have an eye test?Optometrists recommend that everyone over the age of 40 has an eye test about every two years. This is especially important if you are over 60.
What should I do if I notice a change in my sight?Visit your GP or optometrist if you're concerned with any aspect of your vision at any time.
What about my child's sight?Children do not usually complain about their sight, but may show signs of not being able to see properly. Things to look out for include sitting close to the TV, holding objects very close to their face, blinking a lot, eye rubbing, or one eye turning in or out. If your child is having any sort of sight problems, see an optometrist for further investigation.
What else can I do to look after my eyes?Give up smoking Smokers are much more likely to develop age-related macular degeneration and cataracts compared to non-smokers. Keep moving While it might seem odd that exercise can help the eyes, it can be important. Research shows that exercise may reduce the risk of sight loss, which can occur as a result of high blood pressure, diabetes, and narrowing or hardening of the arteries. Eat healthily A healthy balanced diet, with a wide variety of fruit and vegetables, will benefit your overall health and may help keep the retina healthy. Drink within the recommended limits Heavy alcohol consumption is associated with an increased risk of early age-related macular degeneration. The recommended daily alcohol limits are three to four units for men and two to three units for women. Protect your eyes from the sun Never look at the sun directly, even when something exciting is happening, such as an eclipse. Doing so can cause irreversible damage to your eyesight and even lead to blindness. Several studies also suggest that sunlight exposure is a risk factor for cataracts. Wearing a wide-brimmed hat or sunglasses can help protect your eyes from UV rays. The College of Optometrists recommends buying good-quality dark sunglasses (these needn't be expensive). Look for glasses carrying the CE mark and the British Standard BS EN 1836:2005, which ensures they offer a safe level of ultraviolet protection.
For further information on our schedule of fees, please contact Lynda Hooligan, our finance manager on 01704 552212
By now, you will have been in contact with members of our team.
You will have received your confirmation letter containing specific information about your appointment and have been given an appointment date and time convenient to you.
Planning Your Day at iSIGHT
Depending upon your condition and treatment, MANY INITIAL CONSULTATIONS NECESSITATE HAVING PUPILS DILATED AND YOU WILL NOT BE ABLE TO DRIVE FOR A FEW HOURS AFTERWARDS.Please feel free to bring a companion with you, or make arrangements to be collected later. We will happily contact the person collecting you when you’re ready.
It is advisable to allow between 1-3 hours for your initial consultation, depending upon your eye condition and diagnostic tests needed. If you are attending a Refractive Surgery appointment and you wear contact lenses, please leave soft lenses out for at least 1 week; hard lenses preferably for 4 weeks.
On arrival, a member of our friendly reception team will greet you and show you into our beautiful drawing room where you will be offered light refreshments. There is a television and we have free wi-fi. Once you are comfortable, a member of the clinical team will come and introduce themselves.
Typically, your vision will be checked by one of our clinicians and you will have the opportunity to discuss your eye condition and any worries and anxieties you may have.
You will then meet your surgeon who will perform a thorough eye examination. This surgeon will follow you through your patient journey. He or she will request specific tests depending upon your condition. The tests are usually done on the same day in one of our diagnostic suites.
It is useful to write down any questions you may wish to discuss with your surgeon beforehand.
Your condition will be discussed fully, including the risks, benefits and any other option available to you.
If you decide to proceed with the treatment offered, one of our patient co-ordinators will contact you with all the relevant information you will need.
If you have worries about your medical insurance covering you, please contact our finance department on 01704 552212.
We have free parking onsite and there is plenty of parking on the roads nearby.
How do I make an appointment?
Call us 01704 552218, or complete the Enquiry Form on our website.
What are your opening hours?
Monday-Friday / 8.30am-5pm
Is there disabled access?
Yes, there disabled access. Follow the wheelchair access sign.
Is there any parking onsite?
There is free onsite parking. There is free street parking near the clinic.
What do I bring to an appointment?
A list of current medications
Your referral letter
Opticians sight test report (if available)
The completed questionnaire
A companion to take you home as your pupil’s may be dilated
Why will my pupils be dilated?
This depends on the condition of your eyes and the diagnosis. Dilated pupils help the surgeon to examine the back of your eye to help with diagnosis of any eye condition.
Can I drive after my pupils are dilated?
No, it is not advisable to drive following dilation. Your vision will be blurred and sensitive to light for 4-5 hours.
How long will a new patient appointment take?
Up to an hour, or 2 hours if you require diagnostic tests.
Why do I need a GP referral?
Medical etiquette requires that you are referred to a Specialist by your GP. A letter from your Doctor will provide useful further information on your condition.
What if I can’t get a referral in time for the appointment?
You may still attend your appointment. Please ask your doctor to fax or email your referral to the clinic.
Will I be offered a drink?
Yes, we have hot and cold drinks available.
Can I bring a relative or friend with me to my consultation?
Yes, a relative or friend is welcome to attend with you. However, we do ask only one person accompany you to the clinic if possible.
Existing patient with emergency during the day/ after hours
There is an emergency number left on our answer machine after hours and at weekends. The emergency number is 07725 818244.
Which insurance companies are covered at iSIGHT?
We work with most of the major insurance companies. Please call Lynda Hooligan in our Finance Department on 01704 552212
Do I need approval for treatment from my insurance company?
Yes, You will need to bring an Authorisation Number from your insurance company.
Will my insurance cover everything?
Not necessarily, you will need to check with your insurance company.
How can I pay if I’m not medically insured?
Card/Cheque/BACs. If you would like our bank details, please call Lynda Hooligan on 01704 552212.
Can you help me with medical insurance process?
Yes, please ring Lynda Hooligan, Accounts Manager 01704 552212.
When do I pay for first consultation?
On day of consultation.
When do I pay for follow up appointments?
On day of appointment
When do I pay for surgery?
Usually five days prior to surgery.
Are regular sight tests important?
Yes. It can spot many general health problems and early signs of eye conditions before you are aware of any symptoms – many of which can be treated if found early enough.
How often should I have an eye test?
Optometrists recommend that everyone over the age of 40 has an eye test every one/two years. This is especially important if you are over 60. Your Optometrist will advise you.
What should I do if I notice a change in my sight?
Visit your Optometrist if you’re concerned with any aspect of your vision at any time. If you have symptoms of flashing lights or large amount of floaters you must go to your local optician or eye department for advice
Can I buy glasses or contact lenses?
No. Please purchase from your local optician.
Do you sell visual aids?
No. Please purchase from your local optician.
What is an Ophthalmologist?
An Ophthalmologist is a medically trained doctor who specialises in diseases of the human eye. They examine, diagnose and treat diseases and injuries of the eye. They can prescribe a wide range of medicines and perform various types of surgery.
Can I come to iSIGHT for a second opinion?
Yes. The surgeons are happy to give you a second opinion.
If I want laser surgery, what happens if I’m not suitable?
iSIGHT offers a Free 15 minute consultation with a refractive surgeon to discuss options available to you. However, you will require diagnostic test to assess if suitable for laser.
How do I get a free 15 minute consultation?
Contact the iSIGHT Private on 01704 552218 and ask for details.
What if I change my mind?
You are under no obligation to attend the clinic. However, we do ask you to contact the clinic to cancel your appointment.
Do you have open evenings?
We offer open evenings for the general public from time to time. Please contact us for details.
Age-related macular degeneration (AMD)
A painless eye condition that causes you to lose central vision.
Central vision is what you see when you focus straight ahead. In AMD, this vision becomes increasingly blurred, which means:
- reading becomes difficult
- colours appear less vibrant
- people's faces are difficult to recognize
This sight loss usually happens gradually over time, although it can sometimes be rapid.,AMD doesn't affect your peripheral vision (side vision), which means it will not cause complete blindness.
Macular degeneration develops when the part of the eye responsible for central vision (the macula) is unable to function as effectively as it used to. There are two main types – dry AMD and wet AMD.
Dry AMD develops when the cells of the macula become damaged by a build-up of deposits. It's the most common and least serious type of AMD, accounting for around 9 out of 10 cases.
Vision loss is gradual, occurring over many years. However, an estimated 1 in 10 people with dry AMD go on to develop wet AMD.
Wet AMD – sometimes called neovascular AMD – develops when abnormal blood vessels form underneath the macula and damage its cells.
Wet AMD is more serious than dry AMD. Without treatment, vision can deteriorate within days.
There's currently no cure for either type of AMD. With dry AMD, treatment aims to help a person make the most of their remaining vision – for example, magnifying lenses can be used to make reading easier. Lutein supplements can prevent further deterioration and smoking causes progression of AMD.
Wet AMD can be treated with anti-vascular endothelial growth factor (anti-VEGF) medication. This aims to stop your vision getting worse by preventing further blood vessels developing.
Amblyopia is poor vision in an eye that did not develop normal sight during early childhood. It is sometimes called "lazy eye."
When one eye develops good vision while the other does not, the eye with the poorer vision is called amblyopic. Usually, only one eye is affected by amblyopia, but it is possible for both eyes to be "lazy." This condition is called bilateral amblyopia.
The condition is common; approximately two or three out of every 100 people has amblyopia. The best time to correct amblyopia is during infancy or early childhood, before the age of 7 by patching the good eye to make the lazy eye work better.
Astigmatism is usually the result of an irregular-shaped cornea. The cornea is the transparent window at the front of the eye.
The cornea should be regularly curved like the surface of a football, but in cases of astigmatism it has an irregular curve, more like the shape of a rugby ball. This means that light rays entering the eye aren't focused properly, creating a blurred image.
Astigmatism is a common and usually minor eye condition that causes blurred or distorted vision. Many people who wear glasses have some degree of astigmatism.
Astigmatism belongs to a group of related eye conditions known as refractive errors.
Avastin® is the brand name for bevacizumab, a drug injected into the eye to slow vision loss in people who have “wet” age-related macular degeneration (AMD).
Avastin is part of a class of drugs that block the growth of abnormal blood vessels, which is the cause of wet age-related macular degeneration (AMD). Avastin is also used in some cases to treat macular oedema, or swelling of the macula, often associated with diabetic retinopathy.
Bell's palsy is a temporary condition that causes certain muscles in your face to weaken or become paralyzed. With Bell's palsy, it appears as if half of your face is droopy and you can only smile with one side of your mouth. Usually, you cannot close the eye on that side of your face, and the lower eyelid may also turn outward (called ectropion). This condition can lead to excessive dry eye and tearing in the affected eye.
Bell's palsy occurs when the nerve that controls facial muscles on one side of your face swells or becomes inflamed.
Black eye is a phrase used to describe bruising around the eye due to an injury to the face or the head. Blood and other fluids collect in the space around the eye, causing swelling and dark bruising in the tissue.
When there is trauma or injury to the face, the skin around the eye — which is very loose — is one of the first places to swell as fluid builds up. Although the name "black eye" would indicate otherwise, the eye itself is usually not injured. Many black eyes heal on their own in a few days. However, a black eye can be a sign of a more serious injury. For instance, if there is bleeding within the eye that is called a hyphema and should be looked for any time you see a black eye, and medical advice sought.
Blepharitis is a common and ongoing condition where the eyelids become inflamed (swollen), with oily particles and bacteria coating the eyelid margin near the base of the eyelashes. This annoying condition causes irritation, itchiness, redness, and stinging or burning of the eyes.
Anterior blepharitis affects the outside of the eyelid where your eyelashes are attached. This can be caused by bacterial (or sometimes viral) infection. If left untreated, anterior blepharitis can lead to thickened and inward-turned or outward-turned eyelids and even vision problems from in-turned eyelashes damaging the cornea.
Posterior blepharitis is a condition that results from a dysfunction of the eye's tiny oil glands (meibomian glands) in the eyelids at the base of the eyelashes. When meibomian glands become clogged from posterior blepharitis, it can also can cause a style or chalazion to form. Posterior blepharitis also leads to thickened eyelid margins and crusty eyelids.
Rosacea blepharitis is associated with ocular rosacea, a condition that causes eyelid swelling and redness due to malfunctioning oil glands. Acne rosacea is a common skin condition that leads to pimple-like bumps and facial redness.
Blocked Tear Duct
A blocked tear duct is when the eye’s drainage system for tears is either partially or completely obstructed. Tears cannot drain normally, causing a watery, irritated or chronically infected eye.
Branch Retinal Vein/Artery Occlusion
The retina—the layer of light-sensitive cells at the back of the eye—is nourished by the flow of blood, which provides nutrients and oxygen that nerve cells need. When there is a blockage in the veins into the retina, retinal vein occlusion may occur.
Branch retinal vein occlusion (BRVO) is a blockage of the small veins in the retina. (When there is blockage of the main vein in the retina, it is called Central Retinal Vein Occlusion.) BRAO often occurs when retinal arteries that have been thickened by atherosclerosis (hardening of the arteries) cross over and place pressure on a retinal vein. You can get macula swelling with this also.
Cataract is a clouding of the eye's lens. When we look at something, light rays travel into our eye through the pupil and are focused through the lens onto the retina, a layer of light-sensitive cells at the back of the eye. The lens must be clear in order to focus light properly onto the retina. If the lens has become cloudy, this is called a cataract.
Cataracts usually start to develop in a person's lens as they get older, stopping some of the light from reaching the back of the eye.
Over time, cataracts become worse and start to affect vision. Eventually, surgery will be needed to remove and replace the affected lens.
Symptoms of cataracts
As cataracts develop over many years, problems may be unnoticeable at first. Cataracts often develop in both eyes, although each eye may be affected differently.
You'll usually have blurred, cloudy or misty vision, or you may have small spots or patches where your vision is less clear.
Cataracts may also affect your sight in the following ways:
- You may find it more difficult to see in dim or very bright light
- The glare from bright lights may be dazzling or uncomfortable to look at, particularly when driving at night
- Colours may look faded or less clear
- Everything may have a yellow or brown tinge
- You may have double vision
- You may see a halo (a circle of light) around bright lights, such as car headlights or street lights
- If you wear glasses, you may find that they become less effective over time
Cataracts aren't painful and don't irritate your eyes or make them red.
Central Retinal Vein/Artery Occlusion
The retina, the layer of light-sensitive cells at the back of the eye, is nourished by blood flow, which provides nutrients and oxygen that nerve cells need. When there is a blockage in the veins into the retina, retinal vein occlusion may occur.
Central retinal vein occlusion (CRVO) is a blockage of the main vein in the retina. (Blockage of the small veins in the retina is called branch retinal vein occlusion, or BRVO.) The blockage causes the walls of the vein to leak blood and excess fluid into the retina. When this fluid collects in the macula (the area of the retina responsible for central vision), vision becomes blurry.
There are two types of CRVO:
- Non-ischemic CRVO. This is a less serious form of CRVO, which accounts for a majority of cases.
- Ischemic CRVO. This is a more serious form of CRVO that can lead to the development of significant complication & can cause vision loss.
Central Serous Retinopathy
Central serous retinopathy is a disease that causes fluid to build up under the central part of the macula. Because it occurs under the macula region, your vision is usually affected to varying degrees, and can become blurred and distorted. The fluid leaks from the blood vessel layer under the retina. The cause of this is unknown, although stress has been associated with it. It can be caused by steroid use, and if you are on this medication you should see your GP immediately. Men are more at risk then women and it usually occurs around the mid-forties.
Most cases clear up without treatment in a few months. Patients where the condition lasts longer and is more severe may benefit from laser treatment, or another treatment called photodymic therapy to help stop the leak of fluid. This would require referral to see an ophthalmologist.
Chalazion & Stye
A chalazion and a stye are both lumps in or along the edge of an eyelid. In some situations it may be difficult to distinguish between a chalazion and stye.
A stye often appears as a red, sore lump near the edge of the eyelid, caused by an infected eyelash follicle. When a stye occurs inside or under the eyelid, it is called an internal hordeolum.
The term chalazion comes from a Greek word meaning "small lump." A chalazion forms when an oil-producing gland in the eyelid called the meibomian gland becomes enlarged and the gland opening becomes clogged with oil. Chalazia tend to develop farther from the edge of the eyelid than styes. Often larger than stye, a chalazia usually isn't painful.
Belpharitis predisposes people to increase risk of chalazions.
Choroidal Neovascular Membranes
In the eye, a healthy, intact retina is key to clear vision. The retina is the light-sensitive tissue lining the back of the eye. It converts light rays into electrical impulses that travel through the optic nerve to our brain, where they are interpreted as the images we see.
Choroidal neovascular membranes (CNVM) are new blood vessels that grow through the retinal pigment epithelum and disrupt vision. The choroidal circulation is in an area called the choroid, the area between the retina and the sclera (the white part of your eye). The choroid supplies oxygen and nutrients to the eye. Choroidal neovascular membranes occur when new blood vessels start to grow and break through the retinal pigment epithelium onto the internal surface of the retina secondary to aging change in the RPE. When Choroidal neovascular membranes leak causing vision loss.
Choroidal neovascular membrane are associated with many serious eye diseases, but most commonly wet age-related macular degeneration.
Colour blindness occurs when you are unable to see colors in a normal way. Most commonly, colour blindness (also known as colour deficiency) happens when someone cannot distinguish between certain colours, usually between greens and reds, and occasionally blues.
In the retina (the light-sensitive tissue lining the back of the eye), there are two types of cells that detect light: rods and cones. Rods detect only light and dark and are very sensitive to low light levels. Cone cells detect color and are concentrated near the center of your vision. There are three types of cones that see color: red, green and blue (these are often called primary colours). The brain uses input from these three colour cone cells to determine our color perception.
Colour blindness can occur when one or more of the colour cone cells are absent, nonfunctioning, or detect a different color than normal. Severe colour blindness occurs when all three cone cells are absent, and mild color blindness occurs when all three cone cells are present, but one type of cone cell functions abnormally to detect a different colour than normal.
There are different degrees of colour blindness. Some people with mild colour deficiencies can see colors normally in good light but have difficulty in dim light. Others cannot distinguish certain colours in any light. The most severe form of colour blindness, in which everything is seen in shades of gray, is uncommon. Colour blindness usually affects both eyes equally and remains stable throughout life.
Colour blindness is usually something that you have from birth, and often has a genetic link, but it can be acquired later in life. Change in colour vision can signify a more serious condition. Anyone who experiences a significant change in colour perception should see an Ophthalmologist.
Conjunctivitis is the term used to describe swelling (inflammation) of the conjunctiva — the thin, filmy membrane that covers the inside of your eyelids and the white part of your eye (known as the sclera). Often this condition is called "pink eye."
The conjunctiva, which contains tiny blood vessels, produces mucus to keep the surface of your eye moist and protected. When the conjunctiva becomes irritated or swollen, the blood vessels become larger and more prominent, making your eye appear red. Signs of pink eye may occur in one or both eyes.
There are three types of conjunctivitis:
Bacterial conjunctivitis –This is a highly contagious form of pink eye caused by bacterial infections. This type of conjunctivitis usually causes a red eye with a lot of pus.
Viral conjunctivitis – Is also highly contagious but there is no discharge. The most common cause of pink eye is the same virus that causes the common cold, and is also very contagious.
Allergic conjunctivitis – This form of conjunctivitis is caused by the body's reaction to an allergen or irritant. It is not contagious. Patient’s experience itchy eyes.
Contact Lens Related Infections:
While contact lenses are safely used by millions of people every day, they do carry a risk of eye infection. The most common infection related to contact lens use is keratitis, an infection of the cornea (the clear, round dome covering the eye's iris and pupil). Keratitis can have multiple causes, including viral bacteria & fungal infections. Keratitis is the most serious complication of contact lens wear.
Symptoms of contact lens-related infections may include blurry vision, unusual redness of the eye, pain in the eye, tearing or discharge from the eye, increased light sensitivity or the sensation of something in your eye. It is important to remember that some contact lens-related eye infections can cause serious vision loss, so it is important to see an optometrist or ophthalmologist as soon as possible for treatment.
Always take contact lens to optometrist/ophthalmologist as often the cause of the infection can be ascertained when sent to the laboratory/
Factors that contribute to a contact lens-related infection include:
- Use of extended-wear lenses
- Sleeping in your contact lenses
- Reduced tear exchange under the lens
- Environmental factors
- Poor hygiene, including poor maintenance of contact lens cases or reusing contact lens solution
Safe handling, storage and cleaning of your lenses are key steps to reduce your risk of a keratitis infection.
Very painful watery eye.
Corneal abrasion is a scratch or scrape on the cornea, the clear, round dome covering the eye's iris and pupil. By helping to focus light as it enters the eye, the cornea plays an important role in vision. When a corneal abrasion scars the cornea, it can affect vision.
Corneal abrasions can often be prevented by using protective eyewear when performing activities that put your eyes at risk of injury.
Corneal erosion affects the cornea, the clear dome covering the front of the eye. The cornea is composed of five layers. The outermost layer is the epithelium. When the epithelium does not stay attached correctly to the corneal tissue below, including the layer called the Bowman's layer or the basement membrane, this can cause a condition called recurrent erosion syndrome. If the problem occurs repeatedly, it is called recurrent corneal erosion.
The most common symptom of corneal erosion is mild to severe pain. The pain may be particularly uncomfortable in the morning upon awakening because the eyes naturally get dry at night, and the eyelid can stick slightly to the epithelium. If the epithelium is not firmly attached, sometimes opening the lids can cause the epithelium to tear off. Without treatment, your eyes may continue to experience this erosion.
Other symptoms include:
- Feeling of something in the eye
- Light sensitivity
- Blurred vision
- Watery eyes (particularly on awakening)
A corneal ulcer is an open sore on the cornea — the clear front window of the eye. The cornea covers the iris (the colored portion of the eye) and the round pupil, much like a watch crystal covers the face of a watch. A corneal ulcer usually results from an eye infection, though it can be caused by severe dry eye or other eye disorders. Usually treated with a course of antibiotics.
Detached or Torn Retina
The retina is the light-sensitive tissue, lining the back of our eye. Light rays are focused onto the retina through our cornea, pupil and lens. The retina converts the light rays into impulses that travel through the optic nerve to our brain, where they are interpreted as the images we see.
A healthy, intact retina is key to clear vision. The middle of our eye is filled with a clear gel called vitreous that is attached to the retina. Sometimes tiny clumps of gel or cells inside the vitreous causes floaters, and you may sometimes see small dots, specks, strings or flies, spiders web, moving in your field of vision. These are called floaters. As we get older, the vitreous may shrink and pull on the retina. When this happens, you may notice what look like flashing lights, lightning streaks. These are called flashes.
Usually, the vitreous moves away from the retina without causing problems. But sometimes the vitreous pulls hard enough to tear the retina in one or more places. Fluid may pass through a retinal tear, lifting the retina off the back of the eye. When the retina is pulled away from the back of the eye like this, it is called a retinal detachment. The retina does not work when it is detached and vision becomes blurry. A retinal detachment is a very serious problem that can cause blindness unless it is treated with detached retina surgery.
Torn retinas if caught early before causing a detachment are amenable to retinopexy laser to seal the tears. This prevents a retinal detachment.
Diabetic retinopathy, the most common diabetic eye disease, occurs when blood vessels in the retina change. Sometimes these vessels become dilated and leak fluid or even close off completely. New blood vessels may grow.
The retina is a thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see. The macula is a very small area at the center of the retina. It is the macula that is responsible for your vision that allows you to read, sew or recognise a face. The surrounding part of the retina, called the peripheral retina, is responsible for your side — or peripheral — vision.
Diabetic retinopathy usually affects both eyes. People who have diabetic retinopathy often don't notice changes in their vision in the disease's early stages. But as it progresses, diabetic retinopathy usually causes vision loss that in many cases cannot be reversed. Diabetic patients are usually screened yearly for diabetic retinopathy.
Dilating Eye drops
Dilating eye drops are used to dilate, or enlarge, the pupils of your eyes so that your optometrist or ophthalmologist can see the inside of your eye in detail.
With your pupils dilated, your ophthalmologist can use special instruments to see the eye’s entire lens, which focuses light onto the retina (the light-sensitive tissue lining the back of the eye). The retina itself also can be seen, as well as the optic nerve, which sends signals from the retina to your brain where they are interpreted as images.
In addition to eye examinations, dilating eye drops are used for a variety of purposes.
For example, some types of eye surgery or your eyes may also be dilated to relax your lens’s focusing muscles so that your optometrist can measure accurately for your glasses prescription (usually only children).
Double vision is seeing two, often overlapping, images of a single object.
Double Vision may be associated with other eye disorders such as Black Eye, Cataract, Migraine, Strabismus.
If you notice any double vision, visit your local optometrist.
Drooping eyelid is when the upper lid does not open fully and can partially block vision. This can be caused by some other eye disorders.
However, for others it can be purely cosmetic and treated with cosmetic surgery for those who want a more youthful look.
Drusen are yellow deposits under the retina, the light-sensitive tissue at the back of the eye. Drusen are made up of lipids, a fatty protein. Whilst Drusen is not thought to cause age-related macular degeneration (AMD), their presence increases a person’s risk of developing AMD. There are different kinds of Drusen.
“Hard” drusen are small, distinct and far away from one another. This type of Drusen may not cause vision problems for a long time, if at all.
“Soft” drusen are large and cluster closer together. Their edges are not as clearly defined as hard Drusen. This soft type of Drusen increases the risk for AMD.
Drusen of the optic nerve - Drusen can also occur in the optic nerve. These Drusen are made up of protein and calcium salts and generally appear in both eyes. Unlike the Drusen associated with AMD, optic nerve Drusen (also known as optic disc drusen) are not related to aging and often appear in children. Optic nerve Drusen usually do not affect vision, but some patients with these drusen may lose peripheral (side) vision. They are benign.
When you blink, a film of tears spreads over the eye, making the surface of the eye smooth and clear. Without this tear film, good vision would not be possible.
Sometimes people don't produce enough tears or the right quality of tears to keep their eyes healthy and comfortable. This condition is known as dry eye.
Normally, the eye constantly bathes itself in tears. By producing tears at a slow and steady rate, the eye stays moist and comfortable.
The eye uses two different methods to produce tears. It can make tears at a slow, steady rate to maintain normal eye lubrication. It can also produce a lot of tears in response to eye irritation or emotion. When a foreign body or dryness irritates the eye, or when a person cries, excessive tearing occurs.
It may not sound logical that dry eye would cause excess tearing, but it is the eye's response to discomfort. If the tears responsible for maintaining lubrication do not keep the eye wet enough, the eye becomes irritated. Eye irritation prompts the gland that makes tears (called the lacrimal gland) to release a large volume of tears, overwhelming the tear drainage system. These excess tears then overflow from your eye.
Eyelid spasm or twitching
Eyelid spasm, or twitching (which is also called blepharospasm), is an abnormal, involuntary blinking or movement of the eyelids. The blinking can happen every few seconds and may even be strong enough to make your eyelid shut entirely before reopening.
The spasms can last for irregular periods of time, from days to months, and may come and go at random. While the twitching is not painful, it can be annoying. For most people, the twitching eventually goes away on its own, although it may sometimes return.
You should see an ophthalmologist if any of the follow occur:
- The twitching lasts longer than a week;
- Your eyelid involuntarily closes after each twitch;
- Your eye is red, swollen or has discharge, or your eyelids are drooping
Eyelid turns out - Ectropion
When an eyelid turns outward, the lid bends away from the eye so that the edge of the lid no longer touches the eyeball. It is called an Ectropion, it is not usually serious, but can be uncomfortable. Ectropion is often age-related.
Ectropion mainly affects the lower eyelid and can occur in one or both eyes.
The drooping eyelid can disrupt the drainage of tears, which can make the eyes:
- Sore, red and irritated
- Water excessively
- Feel very dry and gritty
- More vulnerable to bacterial infections, such as conjunctivitis
Eyelid turns in – Entropion
Entropion is where the eyelid rolls inwards. It usually affects the lower lids, but it can also affect the upper lids. Entropion is often age-related.
Entropion usually causes an uncomfortable watery eye because the lashes irritate the front of the eye (cornea). If this is mild, using eye drops may be enough to protect the eye and keep you comfortable.
Severe entropion can be painful and cause vision loss by damaging the cornea. Surgery may be needed to correct entropion if it's posing a risk to the health of your eye or is causing considerable discomfort. This is carried out under local anaesthetic.
Hyperopia (farsightedness), is a refractive error, which means that the eye does not bend or refract light properly to a single focus on the retina to see images clearly. People with hypertopia tend to have smaller than average eyes and the image is focused behind the retina. This corrected with a convex lens or a ‘+’ spectacle prescription. In hyperopia, distant objects look somewhat clear, but close objects appear more blurred.
Flashes & Floaters
You may sometimes see small specks or clouds moving in your field of vision. These are called floaters. You can often see them when looking at a plain background, like a blank wall or blue sky. Floaters are actually tiny clumps of cells or material inside the vitreous, the clear, gel-like fluid that fills the inside of your eye.
While these objects look like they are in front of your eye, they are actually floating inside it. What you see are the shadows they cast on the retina, the layer of cells lining the back of the eye that senses light and allows you to see. Floaters can appear as different shapes, such as little dots, circles, wiggly lines, clouds or cobwebs.
When the vitreous gel pulls on the retina, you may see what look like flashing lights or lightning streaks. These are called flashes, they look like lightening or shooting stars. The flashes of light can appear off and on for several weeks or months, and will be more noticeable at night.
As we grow older, it is more common to experience floaters and flashes as the vitreous gel changes with age, gradually pulling away from the inside surface of the eye.
Fuchs’ Endothelial Dystrophy
Fuchs' Endothelial Dystrophy is a progressive disease affecting the part of the eye called the cornea, the clear, round dome covering the eye's iris and pupil. By helping to focus light as it enters the eye, the cornea plays an important role in vision.
Fuchs' Endothelial Dystrophy reduces the number of specific cells (called endothelial cells) that make up the inner layer of the cornea. Endothelial cells are key to processing water that makes up the corneal cell structure. When the endothelial cells diminish, the cells stop processing water properly and fluid starts to build up. The corneal tissue gradually thickens, causing the cornea to become swollen and cloudy, losing its crystal-clear transparency.
As Fuchs' Endothelial Dystrophy is a progressive disease, over time, changes to the corneal cells may interfere with vision. The condition can result in corneal scar tissue, which may have to be removed surgically.
Fuchs' Endothelial Dystrophy is somewhat more common in women and usually affects people in their 50’s or 60’s.
Fungal keratitis is an infection of the cornea (the clear, round dome covering the eye's iris and pupil) that causes pain, reduced vision, light sensitivity and tearing or discharge from your eye. Resulting from infection from contact lens use or from injury to the eye, fungal keratitis usually develops very quickly, and you should ensure prompt treatment.
Glaucoma is a disease that damages the eye's optic nerve. It usually happens when fluid builds up in the front part of your eye. That extra fluid increases the pressure in your eye, damaging the optic nerve.
When glaucoma develops, usually you don’t have any early symptoms, as it affects the peripheral vision, and the disease progresses slowly. In this way, glaucoma can steal your sight very gradually. Fortunately, early detection and treatment (with glaucoma eye drops, glaucoma surgery or laser) can help preserve your vision.
The optic nerve is connected to the retina, a layer of light-sensitive tissue lining the inside of the eye, and is made up of many nerve fibers. The optic nerve sends signals from your retina to your brain, where these signals are interpreted as the images you see.
In the healthy eye, a clear fluid called aqueous humor circulates inside the front portion of your eye. To maintain a constant healthy eye pressure, your eye continually produces a small amount of aqueous humor while an equal amount of this fluid flows out of your eye. If you have glaucoma, the aqueous humor does not flow out of the eye properly or too much is produced. Fluid pressure in the eye builds up and, over time, causes damage to the optic nerve fibres.
You should seek our advice if:
- There is a sudden increase in the number of floaters
- If you experience flashing lights often like lightening
- Or an area of vision is missing
A Hyphaema is a collection of blood inside the front part of the eye (called the anterior chamber, between the cornea and the iris). The blood may cover part or all of the iris (the colored part of the eye) and the pupil, and may partly or totally block vision in that eye. Hyphema is usually caused by trauma to the eye, though other conditions may cause hyphema as well.
Unlike a subconjunctival hemorrhage, a generally painless, harmless condition where blood appears on the white part of the eye due to a broken blood vessel, a hyphema is usually painful and can cause permanent vision problems if not treated properly.
An intraocular lens (IOL) is a clear, artificial lens implant used to replace a cloudy natural lens in cataract surgery.
Like your eye's natural lens, an IOL focuses light that comes into your eye through the cornea and pupil onto the retina, the sensitive tissue at the back of the eye that relays images through the optic nerve to the brain. Like the lenses of prescription spectacles, your IOL will contain the appropriate prescription to give you the best vision possible.
Idocorneal Endothelial Syndrom (ICE)
Idocorneal Endothelial Syndrome (ICE) is a rare eye condition whose three main features include:
- Swelling of the cornea, which is the clear, front part of the eye;
- Changes in the iris, which is the colored part of the eye; and
- A form of glaucoma.
ICE is actually a group of conditions related to changes in corneal endothelial cells and the iris. The syndrome almost always involves cells moving from the cornea to the drainage angle of the eye. Loss of cells from the cornea can cause corneal swelling, and the iris and pupil can become distorted. Also, when the corneal cells move, they can block fluid from draining properly through the eye’s microscopic drainage channels. This blockage causes pressure in the eye to build, leading to glaucoma.
Ischemic Optic Neuropathy (ION)
Ischemic optic neuropathy (ION) is a sudden loss of central vision, side vision or both due to a decreased or interrupted blood flow to the eye’s optic nerve.
In order to see, the optic nerve carries impulses from the eye to the brain, where they are interpreted as images. The optic nerve is made up of a million tiny, delicate nerve fibers that are like wires. Many blood vessels nourish the optic nerve with blood rich in oxygen and nutrition. Without a healthy, functioning optic nerve, vision would not be possible.
Some ophthalmologists may describe ischaemia of the optic nerve as a “stroke at the back of the eye.” A “stroke" is an interruption of the blood supply to the brain or a nerve in the body. With ischemic optic neuropathy, vision loss occurs because the optic nerve has lost blood circulation. How much vision is lost depends on how much the optic nerve is affected.
Keratitis is a condition where the cornea—the clear, round dome covering the eye’s iris and pupil—becomes swollen or inflamed, making the eye red and painful and affecting vision.
Some forms of keratitis may involve an infection, including bacterial keratitis, viral keratitis, fungal keratitis and parasitic keratitis. Contact lens wearers need to remember that infectious keratitis can result from not caring for your contact lenses properly.
A non-infectious form of keratitis may be caused by a simple fingernail scratch or from wearing your contact lenses too long.
Whatever form of keratitis you may have, it is crucial that you see an ophthalmologist right away. Waiting to have your keratitis diagnosed and treated can lead to serious complications.
If you wear contact lenses it is important to bring the lenses and the case with you when you see the doctor.
Keratoconus is an uncommon condition in which the normally round, dome-like cornea (the clear front window of the eye) becomes thin and develops a cone-like bulge. Keratoconus literally means “cone-shaped cornea.”
The cornea is a very important part of your eye. Light enters the eye through the cornea, which refracts, or focuses, the light rays so that you can see clearly.
It typically affects younger people and presents with worsening, rapidly changing, vision.
With keratoconus, the shape of the cornea is altered, distorting your vision. Keratoconus can make some activities difficult, such as driving, typing on a computer, watching television or reading.
It is usually treated with hard contact lenses however, other treatments are available too depending of the degree of reduced vision.
Lasik – Laser Eye Surgery
In recent years laser surgery, or laser refractive surgery, has become more popular as a way to correct eyesight.
The surgery usually involves reshaping the cornea – the transparent layer covering the front of the eye. This is done using a type of laser known as an excimer laser. Different techniques are used to correct short sight (myopia), long sight (hypermetropia) and astigmatism. Laser refractive surgery is generally considered non-essential, as it is treatable with a spectacle prescription it's not usually available on the NHS. LASIK cannot correct presbyopia, the age-related loss of close-up focusing power.
Lazy eye – Amblyopia
Amblyopia is poor vision in an eye that did not develop normal sight during early childhood. It is sometimes called "lazy eye."
When one eye develops good vision while the other does not, the eye with the poorer vision is called amblyopic. Usually, only one eye is affected by amblyopia, but it is possible for both eyes to be "lazy." This condition is called bilateral amblyopia, this however is rare.
Amblyopia is common; approximately two or three out of every 100 people hasamblyopia. The best time to correct amblyopia is during infancy or early childhood. If amblyopia treatment is not begun as early as possible, several problems can develop that can seriously affect vision from childhood into adulthood:
- The amblyopic eye may develop a serious and permanent visual defect;
- Depth perception (seeing in three dimensions) may be lost, because good vision from both eyes is needed;
- If the stronger eye becomes diseased or injured, it can mean a lifetime of poor vision.
Low vision is a loss of eyesight that makes everyday tasks difficult. A person with low vision may find it difficult or impossible to accomplish activities such as reading, writing, shopping, watching television, driving a car or recognising faces.
When vision cannot be improved with regular eyeglasses, medicine or surgery, people with low vision need help to learn how to make the most of their remaining sight and keep their independence. Losing vision does not mean giving up your activities, but it does mean finding new ways of doing them.
Lucentis® is the brand name for ranibizumab, a drug injected into the eye to slow vision loss in people who have “wet” age-related macular degeneration (AMD).
Lucentis is part of a class of drugs that block the growth of abnormal blood vessels, which is the cause of wet AMD. Lucentis was designed specifically as a treatment for wet AMD.
Macular Oedema is swelling or thickening of the eye's macula, the part of your eye responsible for detailed, central vision.
The macula is a very small area at the center of the retina—a thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see. It is the macula that is responsible for your pinpoint vision, allowing you to read, sew or recognise a face.
Macular Oedema develops when blood vessels in the retina are leaking fluids. The macula does not function properly when it is swollen. Vision loss may be mild to severe, but in many cases, your peripheral (side) vision remains.
Macular Oedema is often a complication of diabetic retinopathy, and is the most common form of vision loss for people with diabetes—particularly if it is left untreated.
A macular hole is a small break in the retina at the macula, the part of your eye responsible for detailed, central vision.
The macula is a very small area at the center of the retina — a thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see. It is the macula that is responsible for your pinpoint vision, allowing you to read, sew or recognise a face.
As we grow older, the thick vitreous gel in the back of our eyes shrinks and pulls away from the macula. If the gel sticks to the macula and doesn't pull away, the macular tissue stretches and eventually tears, forming a hole.
If you have macular hole symptoms, you will have blurred and distorted central vision.
A macular pucker (also called an epiretinal membrane) is a layer of scar tissue that grows on the surface of the retina, particularly the macula, which is the part of your eye responsible for detailed, central vision.
The macula is the small area at the center of the eye’s retina that allows you to see fine details clearly. The retina is a layer of light-sensing cells lining the back of your eye. As light rays enter your eye, the retina converts the rays into signals, which are sent through the optic nerve to your brain where they are recognized as images. Damage to your macula causes blurred central vision, making it difficult to perform tasks such as reading small print or threading a needle.
As we grow older, the thick vitreous gel in the middle of our eyes begins to shrink and pull away from the macula. As the vitreous pulls away, scar tissue may develop on the macula. Sometimes the scar tissue can warp and contract, causing the retina to wrinkle or become swollen or distorted.
The macula normally lies flat against the back of the eye. When wrinkles, creases or swelling affect the macula, vision can become blurry and distorted and you may even have a blind spot in your central vision.
Myopia, or nearsightedness / shortsightedness, is a refractive error, and can be corrected by concave spectacle lenses or a ‘-‘ spectacle prescription. The eye does not bend or refract light properly to a single focus to see images clearly. In myopia, close objects look clear but distant objects appear blurred. Myopia is a common condition. It is an eye focusing disorder, not an eye disease.
A naevus (plural, nevi) in the eye is a common, benign, pigmented growth, similar to a mole on your skin. A nevus can occur either in the front of your eye, in the conjunctiva, or around the iris or coloured part of the eye, or beneath the retina in the back of the eye. A naevus beneath the retina is called a choroidal nevus. Sometimes it is called a "freckle in the eye."
While most nevi are harmless, they still need to be watched regularly because, like a skin mole, an eye naevus could possibly develop into an ocular melanoma.
Nystagmus is an involuntary, rapid and repetitive movement of the eyes. Usually the movement is side-to-side (horizontal nystagmus), but it can also be up and down (vertical nystagmus) or circular (rotary nystagmus). The movement can vary between slow and fast, and it usually involves both eyes.
People with nystagmus may not be aware of their eye movements because what they see usually does not appear shaky to them. People with nystagmus may tilt or turn their head in order to see more clearly. This helps to dampen or slow down the eye movements.
Ocular hypertension is when the pressure inside the eye (intraocular pressure or IOP) is higher than normal.
Eye pressure is expressed in millimeters of mercury (mm Hg). Ocular hypertension is not the same as glaucoma, which is a disease of the eye often caused by high intraocular pressure. In people with ocular hypertension, the optic nerve appears normal and no signs of glaucoma are found during visual field testing, which tests peripheral vision. However 10% of patients with Ocular Hypertension will eventually go on to develop Glaucoma, meaning they should be monitored closely by an Ophthalmologist to make sure that they do not develop glaucoma.
Intraocular pressure rises slowly with increasing age, just as glaucoma becomes more common as you get older.
Ocular melanoma (melanoma in or around the eye) is a type of cancer that develops in the cells that produce pigment — the substance that gives your skin, hair and eyes color. Just as you can develop melanoma on your skin, you can also develop it in your eye. Although it is the most common eye cancer in adults, ocular melanoma is rare.
Most eye melanomas form in the part of the eye you can't see when looking in a mirror, they can be difficult to detect. In addition, eye melanoma typically doesn't display any early signs or symptoms. Most melanomas are detected during a routine eye exam. That’s why it is so important to see your optometrist regularly.
Optic neuritis is an inflammation of the eye's optic nerve. It is thought to be an autoimmune disorder, in which body's immune system mistakenly attacks optic nerve tissue, causing swelling and impaired function of the optic nerve.
In order for you to see, the optic nerve carries nerve impulses from the eye to the brain, where they are interpreted as images. Damage or infection of the optic nerve can significantly affect vision as well as colour vision. Vision is often worse if you take a hot shower or drink a hot drink.
Optical Coherence Tomography (OCT)
Optical coherence tomography (OCT) is a non-invasive imaging test that uses light waves to take cross-section pictures of your retina, the light-sensitive tissue lining the back of the eye.
With OCT, each of the retina’s distinctive layers can be seen, allowing your ophthalmologist to map and measure their thickness. These measurements help with diagnosis and provide treatment guidance for glaucoma and retinal diseases, such as age-related macular degeneration and diabetic eye disease.
Photokeratitis is a painful eye condition that occurs when your eye is exposed to invisible rays of energy called ultraviolet (UV) rays, either from the sun or from a man-made source.
Photokeratitis is like having a sunburned eye. This condition affects the thin surface layer of the cornea, and the conjunctiva, which is the cell layer covering the inside of the eyelids and the whites of the eye.
Photokeratitis is caused by damage to the eye from ultraviolet (UV) rays. Sunlight is the main source of natural UV rays.
Photokeratitis can be caused by sun reflection from sand, water, ice and snow. It can also happen if you stare at the sun, such as watching a solar eclipse directly without using a special device. A solar eclipse can also cause a burn to the retina, which is long lasting and more serious than temporary corneal damage.
There are also many man-made sources of ultraviolet light, including tanning lamps and sunbeds. Wearing proper eye protection can prevent damage to the eyes from UV rays.
Presbyopia is the inability to focus close up with increasing age. When you are young, the lens in your eye is soft and flexible. The lens of the eye changes its shape easily, allowing you to focus on objects both close and far away.
After the age of 40, the lens becomes more rigid. Because the lens can’t change shape as easily as it once did, it is more difficult to read at close range. This normal condition is called presbyopia.
Since nearly everyone develops presbyopia, if a person also has myopia (nearsightedness), hyperopia (farsightedness) or astigmatism, the conditions will combine.
There are surgical options to treat presbyopia, one is a procedure known as refractive lens exchange. This refractive surgery technique replaces your eye's rigid natural lens with an artificial lens that corrects presbyopia symptoms, providing multifocal vision.
Ptosis is a drooping of the upper eyelid. The lid may droop only slightly, or it may cover the pupil entirely. In some cases, ptosis can restrict and even block normal vision. It can be present in children as well as adults and may be treated with surgery.
- Affect one or both eyelids
- Be inherited
- Be present at birth
- Occur later in life
Redness in the eye can be caused by many conditions and injuries that can lead to irritation, blood in the eye, or swelling of blood vessels.
Refractive Lens Exchange
Refractive lens exchange typically is for people with presbyopia or extreme farsightedness. If you have both presbyopia and moderate to severe hyperopia, Refractive Lens Exchange may be the only viable option for clear vision and minimal reliance on glasses after refractive surgery.
The procedure for refractive lens exchange is virtually identical to cataract surgery.
The difference is that in Refractive Lens Exchange, the lens being replaced is clear, rather than a cloudy lens due to a cataract.
As in cataract surgery, there are different types of IOLs are available to replace your natural lens, depending on your vision needs and the health of your eyes. They are:
- Monofocal - Monofocal lenses provide clear vision at distance, intermediate or near ranges — but not all three at once. Toric IOLs to correct astigmatism also are classified as monofocal IOLs, these lenses are not available to NHS patients.
- Multifocal IOLs. A multifocal lens provides clear vision at multiple distances, Multifocal lenses are not available on the NHS.
Refractive surgery might be a good option for you if you want to decrease your dependence on glasses or contact lenses.
The retina is the light-sensitive tissue lining the back of the eye. Light rays are focused onto the retina through our cornea, pupil and lens. The retina converts the light rays into impulses that travel through the optic nerve to our brain, where they are interpreted as the images we see. A healthy, intact retina is key to clear vision.
The back of the eye is filled with a clear gel called vitreous that is attached to the retina.
Usually, the vitreous moves away from the retina without causing problems. But sometimes the vitreous pulls hard enough to tear the retina in one or more places. Fluid may pass through a retinal tear, lifting the retina off the back of the eye. When the retina is pulled away from the back of the eye like this, it is called a retinal detachment.
The retina does not work when it is detached and vision becomes blurry. It is often described as a curtain of missing vision. A retinal detachment is a serious problem, which should be treated immediately.
Retinoblastoma is cancer of the eye that begins in the retina, the layer of light-sensing cells lining the back of your eye that converts light rays into impulses. The impulses are sent through the optic nerve to your brain, where they are recognised as images.
Retinoblastoma, which can occur in one or both eyes, usually affects young children, but can infrequently occur in adults.
It is often picked up on a photograph when a person has red eye from a camera flash, only in one eye.
Scleritis is a painful inflammation (swelling) of the white part of the eye, which is also known as the sclera. The tough, fibrous tissues of the sclera form a protective outer layer for the eye and make up 83 percent of the eye’s surface.
In almost half of all cases, Scleritis is associated with an underlying autoimmune disorder. Scleritis may affect the front or the back of the eye. Scleritis affecting the back of the eye may reduce vision.
Strabismus is a problem of the eye muscles in which the eyes are not aligned properly and point in different directions. One eye may look straight ahead, while the other eye turns inward, outward, upward, or downward. The eye turn may be consistent, or it may come and go. Which eye is straight (and which is misaligned) may switch or alternate.
Strabismus is a common condition among children. It can also occur later in life. It may run in families; however, many people with strabismus have no relatives with the problem.
A subconjunctival hemorrhage is similar to an ordinary bruise on the skin — it's like a bruise of the eye. It usually appears as a single, concentrated area of red, or many scattered red splotches, on the white of the eye. The redness is blood under the conjunctiva, a clear membrane that covers the white of the eye (called the sclera) and the inner eyelids.
Seeing a subconjunctival hemorrhage on your eye can be alarming. Yet it is actually a common minor occurrence. It is almost always harmless and will heal on its own. It does not affect vision and generally does not cause pain. There are usually no sensations or symptoms, other than the appearance of the red area.
Trichiasis is a common eyelid abnormality in which the eyelashes are misdirected and grow inwards toward the eye.
Those inward-turning lashes rub against the cornea (the clear, dome-like window covering the colored iris and the pupil), the conjunctiva (the thin, clear membrane covering the sclera, which is the white part of the eye) and the inner surface of the eyelids, irritating the eye.
Tunnel vision is the result of loss of peripheral vision. The only usable vision remaining after loss of peripheral vision is central vision, producing a tunnel effect.
Uveitis is inflammation of the uvea, which is made up of the iris, ciliary body and choroid. Together, these form the middle layer of the eye between the retina and the sclera (white of the eye).
The eye is shaped like a tennis ball, with three different layers of tissue surrounding the posterior gel-filled cavity, which is called the vitreous. The innermost layer is the retina, which senses light and helps to send images to your brain. The outermost layer is the sclera, the strong white wall of the eye. The middle layer between the sclera and retina is called the uvea, at the front of the eye and the choroid at the back of the eye. The uvea contains many blood vessels — the veins, arteries and capillaries — that carry blood to and from the eye. The choroid nourishes many important parts of the eye (such as the retina), inflammation of the uvea can damage your sight.
Symptoms of uveitis include:
- A painful red eye– the pain can range from mild aching to intense discomfort, and focusing your eye can make the pain worse; the eye can feel tender or bruised
- Blurred or cloudy vision – this may come after other symptoms
- Sensitivity to light (photophobia)
- Marked or new floaters– shadows, webs, dots or veils that move across the field of vision (Posterior Uveitis)
- Loss of peripheral vision (the ability to see objects at the side of your field of vision)
- A mid dilated pupil in anterior uveitis, were pupil shaped differently or that doesn't get smaller when reacting to light
Visual Acuity (VA)
Distant vision is tested with a chart with differently sized letters read from a distance of six metres away. This is called the Snellen’s Test Types. Someone who has normal vision has 6/6 vision. This used to be called 20/20 vision when the test was done from 20 feet away before metric measures took over.
6/6 vision does not indicate other important aspects of sight such as peripheral vision, the ability to identify colours or depth perception.
Having 6/12 vision means you can see at six metres what a person with normal vision can see at 12 metres away.
Each eye is tested separately - a score is given for each eye.
For driving, the Department of Work and Pensions says a person needs to be able to read the third line up from the bottom - or 6/10 vision, read a number plate at 20.5 metres and have good peripheral vision using both eyes. This can be with normal eyesight, or corrected with glasses or contact lenses.
Near vision is tested in a different way by looking at a test card with sentences of different font sizes.
Each paragraph is defined with 'points' to measure the print. A point is 1/72 of an inch. In most tests, N48 is the biggest type with N4 the smallest. The chart is read at a comfortable reading distance of about 35cm (14 inches) from the eyes.