Keratoconus is a progressive thinning of the cornea. The cornea is the clear front window of the eye, which, along with the intra-ocular lens, focuses light on to the retina. The cornea normally is a smooth, round dome-shaped structure; however in keratoconus it becomes very thin and irregular and it starts to protrude from the centre or below the centre like a cone. This causes blurry vision that is often not completely correctable with glasses.
The disease is multifactorial in origin but there is a strong genetic component which makes it more frequent in certain parts of the world or within certain families.
Intravitreal Injection
The macula is the central part of the retina at the back of the eye. It is responsible for fine vision (reading, writing, watching television, and recognising faces). Patients with diabetes may develop macular oedema (swelling of the retina) due to leaking of fluid from blood vessels. This causes the vision to become blurred.
A course of three injections is recommended with each injection administered one month apart. The procedure is carried out in a clean environment using sterile technique. The eye is cleaned and local anaesthetic drops are given to numb the eye.
The eye may or may not be covered after the injection. If a pad is applied, this may be removed when you reach home.
Hypermetropia
A refractive condition of the eye in which vision is better for distant objects than for near objects. It can be called far sightedness or hypermetropia. Symptoms of Hypermetropia can include; blurred vision, asthenopia (eye strain), accommodative dysfunction, binocular dysfunction, amblyopia and strabismus. It results from the eyeball being smaller than average, causing images to be focused behind the retina. Hypermetropia should be diagnosed by a qualified Optometrist, Ophthalmic Surgeon or Eye Specialist.
A full Optometric Examination should be performed to assess the degree and extent of the problem. Eyeglasses and contact lenses are the treatment of choice for most people with far sightedness but refractive surgery can also cure some cases of hyperopia.
High Precision Refractive Surgery
When you decide on an eye laser treatment, you expect the best possible results. The more fully developed the methods are, the better the outcome will be. The SCHWIND AMARIS 750S offers you the leading technology for your laser treatment – superior in all important aspects: Speed, precision, safety and comfort.
Diabetic Retinopathy
Introduction
- Diabetic retinopathy is a complication of diabetes and leads to high blood sugar, resulting in retinal disease, which can interfere with its ability to transmit images to the brain through the optic nerve.
- Blood vessels in the retina play an important role in supplying it with oxygen and nutrients, which keep it healthy and working effectively.
Diabetic Retinopathy can result in damage to the blood vessels; these may then bleed, leak or become blocked leading to cell damage in the retina itself.
There are varying forms and levels of severity of diabetic retinopathy – for example, when the retina becomes very damaged, new blood vessels may grow on it and can burst, leading to bleeding and blurred vision. If the macula (the central area of the retina) is affected – this is called Diabetic Maculopathy – the disease has reached a much more advanced and serious stage.
High blood pressure combined with diabetes leads to an even more dangerous condition.
Types of Diabetic Retinopathy
Non Proliferative Diabetic Retinopathy
Generally, this type of diabetic retinopathy does not affect vision because at the initial stage there are just a few enlarged blood vessels, with very minimal bleeding and leaking in the retina.
An examination of the retina by an ophthalmologist will reveal some marks indicating the presence of the condition.
Proliferative Diabetic Retinopathy
This condition can lead to seriously impaired vision as blood vessels grow in the retina and the threat is bleeding from these vessels which can lead to retinal damage, and even to retinal detachment at the back of the eye. Laser treatment is essential to avoid serious long term damage.
Diabetic Maculopathy
Diabetic maculopathy occurs when blood vessels leak into the central area of the retina, which can lead to it swelling and affecting the quality of vision. Laser procedures, injections or surgery are the main treatment options.
Exudates are deposits in the retina from leaky vessels. Haemorrhages in the retina of varying sizes.
Microaneurysms.
Optic Nerve with abnormal new vessels that have bled. Scars from previous laser treatment.
Vitreous haemorrhage in front of the retina.
End stage proliferative Diabetic Retinopathy with fibrousbands.
Retinal Detachment.
Cross sectional scan showing thickening of the macula and exudates.
Exudates (yellow) and haemorrhages in the central retina
Can it be prevented?
Compliance with treatment for diabetes helps control blood sugar levels and blood pressure and so the serious complications of diabetes, including diabetic retinopathy.
Treatment compliance along with regular check ups to monitor blood pressure will help avoid the serious long term effects of diabetes; positive lifestyle choices from balanced diet to regular exercise and not smoking all have a beneficial effect.
What can I do?
Early diagnosis and treatment of diabetes and diabetic retinopathy will generally help prevent serious vision loss for most patients and regular visits to the doctor and ophthalmologist are an essential part of the monitoring process.
Corneal Transplantation (PK)
Why do you need a corneal transplant?
The cornea is a window of transparent tissue at the front of the eyeball. It allows light to pass into the eye and provides focus so that images can be seen. Various diseases or injury can make the cornea either cloudy or out of shape. This prevents the normal passage of light and affects vision.
A cloudy cornea can be replaced by a healthy one from a donor to restore vision.If the full thickness of the cornea is affected by disease, then a full thickness transplant is performed. This is known as a penetrating keratoplasty.
Benefits of penetrating keratoplasty
Improved vision
- Approximately 75% of transplant recipients have vision sufficient to drive legally but may need glasses or contact lenses or sometimes further surgery for best results.
- It may take up to 18 months until the full improvement in vision is appreciated.
Risks of penetrating keratoplasty
Rare but serious complications
- Sight-threatening infection (1 in 1,000)
- Severe haemorrhage causing loss of vision
- Retinal detachment
- Severe inflammation or other rare causes of loss of vision
Corneal transplant rejection
A corneal transplant can be identified and attacked by your immune system. This happens in one in six patients in the first two years after transplantation and can cause graft failure. It can often be reversed if anti-rejection medication is started promptly.
Rejection remains a possibility for your lifetime.
Graft failure
When a graft fails, your cornea becomes cloudy again and your vision becomes blurred. This happens in one in 10 transplants for keratoconus in the first 10 years.
Glaucoma
This can usually be controlled by eye drops, but occasionally requires surgery and can damage the sight.
Cataract
This can be removed surgically.
About the operation
The operation
The operation is performed under general or local anaesthetic. The operation takes about one hour. A central 8mm button of your cornea is removed and a similar-sized button of the donor cornea is stitched in with tiny stitches (see front cover). These cannot be felt or seen. The abnormal cornea, which is removed, is sent to our pathology laboratory for examination under a microscope.
After the operation
You will usually be examined by the surgical team after the surgery and can generally go home the same day. You will be seen again within one week in the outpatient clinic and regularly thereafter (approximately six visits in the first year). We generally recommend that you take two weeks off work – discuss your individual circumstances with your doctor. You will need to use anti-rejection eye drops for at least six months and in some cases indefinitely. Individual
stitches may be removed from three months after the operation, but complete stitch removal is not performed until at least one year after the procedure.
What if my transplant fails?
A failed transplant can be replaced in a procedure known as a regraft, but the risk of subsequent rejection and failure increases each time for regrafts.
The percentages of full-thickness corneal grafts that are still functioning well five years after the operation under various conditions are:
| Condition | % |
|---|---|
| Keratoconus | 95 |
| Fuchs’ dystrophy | 80-90 |
| Stormal Scar | 80-90 |
| Stromal dystrophies | 80-90 |
| Bullous keratopathy | 50-80 |
| Bacterial infections | 50-80 |
| Herpetic keratitis | 50-80 |
| Fungal infection | 0-50 |
| 3rd or higher number regraft | 0-50 |
| 4 quadrants of blood vessels | 0-50 |
| Inflammation at time of surgery | 0-50 |
| Severe ocular surface disease | 0-50 |
| Grafts greater than 10mm | 0-50 |
Consenting for information sharing
We are required to share your information with the Eye Bank who supply donor corneas, to ensure high quality transplant material.
Corneal transplant rejection
Rejection needs urgent treatment as this can lead to failure of the transplant and loss of vision.
Symptoms of rejection are:
- Red eye
- Sensitivity to light
- Visual loss
- Pain
If you experience any of these symptoms, you should immediately call our 24-hour emergency phone line 055 516 1586.
Corneal Transplantation (EK)
Why do you need a corneal transplant?
The cornea is a window of transparent tissue at the front of the eyeball. It allows light to pass into the eye and provides focus so that images can be seen. Various diseases or injury can make the cornea either cloudy or out of shape. This prevents the normal passage of light and affects vision.
The cornea has three layers (thin outer and inner layers and a thick middle layer). In some diseases, only the inside layer (endothelium) is affected, causing corneal oedema (swelling) and clouding (see below). Endothelial keratoplasty is a modern technique to replace the inside layer of your cornea with the inside layer from a donor cornea through a relatively small incision (opening).
Benefits of endothelial Keratoplasty
Improved vision
The majority of transplant recipients have sufficiently good vision to be able to drive legally although many need glasses. It can take up to six months until the full improvement is appreciated. Comfort is improved in some cases.
Risks of endothelial Keratoplasty
Rare but serious complications
- Sight-threatening infection (1 in 1,000)
- Severe haemorrhage causing loss of vision
- Retinal detachment
- Severe inflammation or other rare causes of loss of vision
Corneal transplant rejection
A corneal transplant can be identified and attacked by your immune system. This happens in between 6% and 10% of DSAEK recipients in the first two years after transplantation and can cause graft failure. It can often be reversed if anti-rejection medication is started promptly. Rejection remains a possibility for your lifetime. The rejection risk in DMEK appears to be lower than in DSAEK.
Graft failure
When a graft fails, the cornea becomes cloudy again and vision becomes blurred.
Glaucoma
This can usually be controlled by eye drops, but occasionally requires surgery and can damage your sight.
Graft dislocation
About 10% of endothelial grafts dislocate and need to be repositioned in theatre.
Cataract
This can be removed surgically.
Possible advantages of EK over full-thickness graft
- Faster recovery
- Fewer stitches, which means that the shape of the cornea is more “normal” and you are less dependent on glasses/ contact lens
- Smaller wound so fewer wound complications such as leakage or wound rupture after accidental injury
About the operation
The operation
The operation is usually performed under local anaesthetic and takes about one hour. Through a small incision (opening), your endothelium is removed and an 8.5mm disc of donor endothelium is inserted and pressed in position against the back of your cornea by a bubble of air. You will need to lie flat for one hour after the operation. Usually, only two stitches are used to close the incision.
After the operation
You will usually be examined by the surgical team after your surgery and can generally go home the same day. You will be seen again the next day and within one week to make sure the graft stays in position. You will have about six visits to the outpatient clinic in the first year. We generally recommend that you take two weeks off work – discuss your individual circumstances with your doctor. You will need to use anti-rejection eyedrops for at least six months and in some cases indefinitely. The stitches are usually removed at about three months.
What if my transplant fails?
A failed transplant can be replaced in a procedure known as a regraft. However, the risk of subsequent rejection and failure increases each time for second and subsequent regrafts.
Consenting for information sharing
We are required to share your information with the Eye Bank who supply donor corneas, to ensure high quality transplant material.
Corneal transplant rejection
Rejection needs urgent treatment as this can lead to failure of the transplant and loss of vision.
Symptoms of rejection are:
- Red eye
- Sensitivity to light
- Visual loss
- Pain
If you experience any of these symptoms, you should immediately call our 24-hour emergency phone line 055 516 1586.
Corneal Transplantation (DALK)
Why do you need a corneal transplant?
The cornea is a window of transparent tissue at the front of the eyeball. It allows light to pass into the eye and provides focus so that images can be seen. Various diseases or injury can make the cornea either cloudy or out of shape. This prevents the normal passage of light and affects vision. The cornea has 3 layers (thin outer and inner layers and a thick middle layer). In some diseases, only the middle layer or part of the middle layer is affected (see below).
DALK is a modern technique whereby the outer two layers of the cornea are removed and replaced with the outer 2 layers from a donor cornea to give a partial-thickness transplant.
Benefits of Deep Anterior Lamellar Keratoplasty
Improved vision
- 90% of transplant recipients reach driving standard if the eye is otherwise healthy but can need glasses or contact lenses or sometimes further surgery for best results.
- It may take up to 18 months until the full improvement in vision is appreciated.
Risks of Deep Anterior Lamellar Keratoplasty
Rare but serious complications
- Sight-threatening infection (1 in 1000)
- Severe haemorrhage causing loss of vision
- Retinal detachment
Corneal transplant rejection
A corneal transplant can be identified and attacked by your immune system. This happens in less than 10% of DALK recipients in the first two years after transplantation and can cause graft failure. It can often be reversed if anti-rejection medication is started promptly. Rejection remains a possibility for your lifetime.
Graft Failure
When a graft fails the cornea becomes cloudy again and vision becomes blurred.
Glaucoma
This can usually be controlled by eyedrops but occasionally requires surgery.
Cataract
This can be removed surgically. Conversion to penetrating keratoplasty. Occasionally it is not possible to perform a partial thickness transplant and a full-thickness transplant must be performed instead. This happens in 10% of intended DALK procedures.
Possible advantages of DALK over full-thickness graft
- Lower risk of intraocular problems such as serious infection or bleeding.
- Lower risk of graft rejection.
- The corneal wound after DALK is stronger than that after a full-thickness graft (PK). This means that stitches can be removed sooner.
Possible disadvantages of DALK over full-thickness graft
DALK recipients have a slightly lower chance of achieving 6/6 vision (excellent vision) than recipients of full thickness grafts.
About the operation
The Operation
The operation is performed under general or local anaesthetic. The operation takes about one hour. A central partial thickness 8mm button of the patient’s cornea is removed and a similar-sized button of the donor cornea is stitched in with tiny stitches (see front cover). These cannot be felt nor seen. The abnormal cornea, which is removed is sent to our pathology laboratory for examination under a microscope.After the operation
After the operation you will usually be examined by the surgical team after the surgery and can usually go home the same day. You will be seen again within 1 week in the outpatient clinic and regularly thereafter (approximately 6 visits in the first year). We generally recommend that you take 2 weeks off work – discuss your case with your doctor. You will need to use anti-rejection eyedrops for at least 6 months and in some cases indefinitely. Individual stitches may be removed from 3 months after the operation but complete stitch removal is not performed until at least 1 year.
What if my transplant fails?
A failed transplant can be replaced in a procedure known as a regraft. However the risk of subsequent rejection and failure increases each time for second and subsequent regrafts.Corneal Transplant Rejection
If not treated urgently this can lead to failure of the transplant and loss of vision.
Symptoms of rejection are:
- Red eye
- Sensitivity to light
- Visual loss
- Pain
If you experience any of these symptoms, you should immediately call our 24-hour emergency phone line 055 516 1586.
Cataract Surgery Treatment
Facts
The term cataract derives from the view we get when looking through a waterfall.
- A cataract is the clouding or opacity of the lens inside the eye. The lens has the shape of a lentil and lies behind the coloured part of the eye, the iris.
- In a normal eye, this lens is clear. It helps focus light rays on to the back of the eye, the retina, which sends messages to the brain allowing us to see. When a cataract develops, the lens becomes cloudy and prevents the light rays from passing to the retina.
- Cataracts usually form slowly and people experience a gradual blurring of vision.
“I didn’t know that I had a cataract until my doctor told me!”
Some people may not be aware that a cataract is developing. It can start at the edge of the lens and initially may not cause problems with vision. Generally, as cataracts develop, people experience blurring or hazing of vision. Often they become more sensitive to light and glare.
I seemed to have to go to the optician more to get new glasses.
There may be a need to get new prescriptions for glasses more often when a cataract is developing. When cataracts worsen, stronger glasses no longer improve sight. Objects have to be held close to the eye to be seen. The hole in the iris, the pupil, may no longer look black. It may instead look white or yellow.
Questions & Answers
Do cataracts spread from eye to eye?
No. But often they develop in both eyes at the same time.
Has my cataract been caused by overuse of my eyes?
No. Cataracts are not caused by over use of the eyes and using the eyes when the cataracts start will not make them get worse.
Are there different kinds of cataract?
Yes. Cataracts can be caused by injuries to the eye. This type of cataract is called a traumatic cataract.
Can children have cataracts?
Yes. Babies can be born with this condition. This is called congenital cataract.
Is there a link between diabetes and cataracts?
Yes. Cataracts are more common in people who have diabetes.
Are cataracts just a part of getting old?
Most forms of cataract develop in adult life. The normal process of ageing causes the lens to harden and become cloudy. This is called age-related cataract and it is the most common type. It can occur at any time after the age of 40.
When do I have my cataract treated?
When the cataract progresses to the point that it is interfering with daily activities and normal lifestyle, cataract surgery is usually the next step. Cataracts don’t grow back after surgery.
Could anything have been done to stop me developing a cataract?
There is no known prevention for cataract. Advanced modern cataract surgery using a small incision is highly successful for the great majority of patients.
Are cataracts removed by laser?
No. Surgery is the only effective way to remove a cloudy lens. It is removed with highly sophisticated state of the art equipment available at Moorfields Eye Hospital Dubai.
I have a cataract developing in both eyes, are both treated at the same time?
No, the second eye is operated on a few weeks later.
Do I need any special tests before the operation?
Yes. We will carry out precise measurements of the eyes. Here at Moorfields Hospital we use the IOL Master, one of the most accurate instruments available at this time.
What kind of anaesthetic is necessary?
Most operations for cataracts are performed under local anaesthetic, drops alone or anaesthetic around the eye. You will be awake during the operation and aware of a bright light, but you will not be able to see what is happening. Occasionally a sedative agent is given to make you feel more relaxed. General anaesthesia is seldom necessary.
Will I have to stay in hospital?
No. All routine operations for cataracts are performed on a day care basis. This means you are admitted to hospital, have your operation and are discharged in the same day.
What does the operation involve?
Modern small incision cataract surgery at MoorfieldsisperformedwithPhac-oemulsification. This technique uses sound waves to soften the lens, which is then removed through a small tube. The natural Lens is replaced with an Artificial Lens also called IOL.The operation takes between 10-20 minutes.
Are there any complications?
There are some possible complications during the operation such as:
- Tearing of the back part of the lens capsule
This is however rare and should be less than 1/1000 in experienced hands.
- Inflammation of the eye
The eye may become red and ache. This is a condition called uveitis and can be treated effectively with drops.
- Blurring of the central vision
An accumulation of fluid in the back of the eye (retina) may occur, causing blurring of the central vision. This is known as cystoid macular oedema. This usually resolves itself within a few weeks.
Serious complications are uncommon following cataract surgery. However, like any kind of operation, problems can occur.
After the operation problems with infection and inflammation can present a few days later. If you experience any of the following contact us immediately:
- Pain
- Light sensitivity
- Red eye
Aftercare
Questions & Answers
Will my eyes need to be covered following the surgery?
Your eye will be covered with a protective plastic eye shield. Some patients may also have an eye pad.
Will I feel any pain after the operation?
As the anaesthetic wears off, there can be a dull ache felt inside and around the eye. You can take paracetamol or other general painkillers that suit you best.
Can I bend down to pray?
Yes, from the following day but you have to be very careful not to injure your eyes or apply any pressure on them.
When will the doctor see me after the operation?
The doctor will see you the day after the operation.
How do I put the eye drops?
A nurse will teach you how to look after your eyes before you are discharged. You will be shown how to clean your eyes and put in the eye drops correctly. Eye drop treatment prevents infection and helps reduce.
Is there anything else I have to do to care for my eye?
You should avoid rubbing or touching your eye. You may find you are sensitive to light, so it is useful to have a pair of plain dark glasses in case you need them. The majority of patients can resume normal physical activity within a week. You should be able to return to work the day following your operation depending on your job, check with the doctor to confirm.
Will I need glasses?
Generally, you will still need glasses for reading and occasionally for distance. You can also choose to have a MULTIFOCAL or an ACCOMODATIVE lens inserted to improve your unaided near vision.
Usually you will have a check-up for your glasses with our Optometrist after 4 weeks. If you would prefer not to depend on the glasses for near vision ask your surgeon about what is available.
Will the lens implant last forever?
Yes. However, 1 in 10 patients will have a thickening of the membrane behind the new lens. This occurs in the months or years following surgery. This is called capsular opacity, and can be effectively treated with the YAG laser in the hospital.
Blepharitis
Facts
- Common condition that causes inflammation of the eye lids and can affect people of all ages.
- It usually affects the rim of the eyelids of both eyes and usually is not serious but still irritating and uncomfortable.
- Eyelids may become crusty and scaly and eyes may feel gritty and very tired with increasing irritation when outdoors in sunshine or around any polluted or smoke filled environment.
- Can be associated with skin conditions such as rosacea and eye conditions like conjunctivitis.
- The symptoms can re-occur at any time but home treatment can calm the symptoms and eyesight is generally not affected.
Treatment
You might be prescribed a combination of treatments described below depending on the type of blepharitis: anterior or posterior.
Cleaning of the lid margin
Dip a clean cotton bud in the solution* and clean away any crusts present on the eyelashes. A mirror may be helpful. Do not clean inside the eyelids as this will make them sore. Repeat the process twice a day.
Wipe along the Lid Margin
*Solution
- Bicarbonate of soda
- Baby shampoo solution
- Normal saline
Use the antibiotic - Hot compresses
Soak a clean gauze in boiled water and hold it on your lids with your eyes closed, for 5 minutes twice a day, being careful that the temperature is not too hot. - Lid massage
Roll your finger/cotton bud towards the margin 10 times each for the top and bottom lid, twice a day. - Antibiotic drops
Apply as directed by pulling the lower lid off the eyeball and letting the drop fall into the pocket without touching the lid. - Antibiotic ointment
Apply as directed, by squeezing 1 cm out of the tube onto your index finger and rubbing it onto the lid margin. It is very important that you follow the instructions in the order shown above.
Top lid, roll downwards
Bottom lid, roll upwards
You must be careful not to touch the eyeball with the cotton bud.
Atropine Drops
What are the effects of Atropine?
Atropine has two effects when instilled in the eyes:
- Dilates the pupil (makes the black part of the eye larger).
- Stops the eye from focusing properly – blurring the child’s near vision temporarily.
Why has my child been prescribed Atropine?
Atropine has been prescribed to enable an eye care specialist to check the back of your child’s eyes andto determine if glasses are required. Atropine drops / ointment may be used when:
- A child’s eyes have failed to dilate sufficiently with Cyclopentolate drops used in the clinic.
- Your child has very dark coloured eyes; the additional pigmentation makes dilation more difficult.
Atropine can also be used on occasion to help ‘relax’ your child into their new glasses or to treat amblyopia (lazy eye).
Astigmatism
Facts
- Astigmatism is a treatable eye condition that can cause blurred vision and headaches.
- It is a refractive condition in which the eye’s optical system is incapable of forming a point image for a point object (images are misconstrued).
- The refractive error of the astigmatic eye stems from a different degree of refraction in different meridians; for example, the image may be clearly focused on the retina in the horizontal plane, but not in the vertical plane, or not on the retina in either plane.
- It occurs when the front surface of the eye is uneven; an irregular shaped cornea or lens prevents light from focusing properly on the retina, the light sensitive surface at the back of the eye. As a result, vision becomes blurred at any distance.
What are the symptoms?
Severe astigmatism:
- Vision blurred or distorted whether the person is reading close up or looking further into the distance.
Mild astigmatism:
- Vision blurred at certain distances
- Tired or dry eyes
- Struggle to focus or read
- Headaches, especially when trying to focus
How is it diagnosed?
Astigmatism should be diagnosed by a qualified Optometrist and/or Ophthalmologist.
A full optometric examination should be done to assess the degree and extent of the problem.
Small children, who may not be able to answer the optometrist’s questions about what they can see, can be assessed using a test called retinoscopy that involves reflected light.
What is the treatment?
In most cases, astigmatism can be corrected by wearing properly fitted spectacles or contact lenses.
Milder astigmatism may not need treatment unless the person has a job that strains their eyes, for example, computer work.
In some cases, astigmatism can be corrected by laser surgery which reshapes the cornea.