What is Retinal Vein Occlusion?
Retinal Vein Occlusion occurs when a retinal vessel is occluded, blocking the drainage of the blood from the retina. This results in the accumulation of blood (retinal hemorrhages) and fluid (macular edema) in the retina and leads to a drop in the visual acuity (clarity of vision).
What are the risk factors for Retinal Vein Occlusion?
Risk factors for Retinal Vein Occlusion include: hypertension, diabetes mellitus, cardiovascular disease, primary open angle glaucoma.
What are the types of Retinal Vein Occlusion?
There are two types of Retinal Vein Occlusion:
- Central Retinal Vein Occlusion (CRVO)
- Branch Retinal Vein Occlusion (BRVO)
How is Retinal Vein Occlusion diagnosed?
Retinal Vein Occlusion is diagnosed clinically with a dilated eye examination. Additional imaging such as fluorescein angiography and ocular coherence tomography (OCT) may be needed to confirm the diagnosis and monitor the progression of the disease.
Treatment:
Treatment of Retinal Vein Occlusion includes:
Ocular treatment:
- Observation if only a small vein is involved and does not affect the macula (central part of the vision).
- Intravitreal injections of either anti-vascular endothelial growth factor (anti-VEGF) agents or steroid injection to treat the macular edema.
- Laser photocoagulation may be administered to the peripheral ischemic retina.
Systemic treatment:
- Management of systemic factors (close control of blood pressure and blood sugar levels).
Prognosis:
Retinal Vein Occlusions tend to have a relatively good prognosis if diagnosed and treated early. Delayed treatment may result in permanent retinal ischemia, neovascular glaucoma and tractional retinal detachment.
This week’s blog on Paediatric Cataract has been contributed by Dr Syed M. Asad Ali, Consultant Paediatric Ophthalmologist, Strabismus and Cataract Surgery
What is Cataract?
Cloudiness or opacity in the natural crystalline lens of the eye is called cataract. It is also called ‘white water’ or ‘white pearl’ because of its white appearance. Cataract is very common in people over the age of 50 but – contrary to common belief – it can happen at any age. When a child is born with a Cataract it’s called Congenital Cataract and it affects the vision by preventing all the light reaching the retina at the back of the eye.
Causes of Cataract in the young
Cataract can occur in one eye (unilateral) or both eyes (bilateral). In Western countries, the incidence of Cataract affecting childhood vision is about 3-4 cases in 10,000 live births. The incidence is higher in Asia.
Bilateral Cataracts can be caused by genetic mutations; over 15 gene defects have now been discovered. There are also systemic associations with metabolic disorders such as galactosemia, Wilson disease and diabetes. It has been noticed in people with Trisomy 21 (down syndrome) as well. If a mother acquires an infection such as rubella, herpes, toxoplasmosis or syphilis, this can cause Cataracts at birth.
Unilateral Cataracts are sometimes associated with other eye diseases like small eye, abnormal front of the eye (anterior segment dysgenesis), inflammation, vitreous and retinal diseases.
Any significant trauma (impact with a sharp or blunt object) to the eye can cause Cataract.
Presentation
At a very early age, parents may notice a white area at the centre of the pupil or an abnormal reflection in the pupil. Some children develop squint due to lazy eye caused by Unilateral Cataract. Children are sometimes brought to the ophthalmologist after failing a school eye test. In the case of Unilateral Cataract, even older children may not realise that they are only seeing with one eye, as they are able to manage well.
Treatment
Treatment of Cataracts depends on a number of factors like age at diagnosis, presence of Unilateral or Bilateral, mild or dense cataract and the presence of lazy eye. Dense Bilateral Cataracts at birth are operated on at around 6-8 weeks of age because early surgery can pose a high risk of Glaucoma (blue water) and delaying surgery beyond 3 months of age can limit the vision improvement, due to the development of lazy eyes. Unilateral Dense Cataract at birth has a poor visual prognosis because of the early development of lazy eye.
Mild Cataracts do occur but significant Cataract treatment involves surgery and the removal of the Cataract. In children under 3-4 years of age, Cataract removal also removes the part of front jelly (vitreous) of the eye.
An intraocular lens (IOL) is usually implanted in children above 1 year of age but this can be done earlier in unilateral cases. The power of the IOL selected also allows for the growth of the eye.
After surgery care is very important and may involve regular eye drops for 4-6 weeks after surgery, regular wearing of glasses, contact lenses and patching (covering the one eye with better vision) for the prescribed number of hours. This requires a lot of support and involvement of the parents
In these cases, early diagnosis and prompt treatment can save children from lifelong sight impairment.
It is important for all children to have regular eye check-ups.
What is Glaucoma?
Glaucoma is an increase in pressure inside the eye and is a potentially blinding condition in childhood. Glaucoma has many potential causes.
Our eyes are filled with a fluid-like substance called aqueous humor, which moves around the eye and drains through tiny passages.
In children, the most common cause of Glaucoma is congenital malformation of these passages during the formation of the eye in the mother’s womb.
Testing your child for Glaucoma
Detecting Glaucoma at an early stage can prevent vision loss. All newborns, soon after birth, undergo a baby wellness check, which includes examining the eye for the presence of red reflex and to test the clarity of the cornea.
What is the cornea and red reflex?
The cornea is like the windshield of a car – if the windshield is clear, we are able to see very well. When the eye pressure increases, the cornea becomes cloudy and the red reflex is not seen. Red reflex can also be dull or absent in the presence of cataract or clouding of the lens. Both of these conditions require urgent intervention.
My child’s eyes are big! Should I be worried?
In many cultures, big eyes are a sign of beauty but unfortunately it is also one of the signs of developing Glaucoma. Since the fluid is trapped inside the eye and cannot drain properly, the eye gradually increases in size, just like filling a balloon with air makes it bigger. This increase in the size of the eye can damage the optic nerve at the back of the eye and which is the main nerve involved in vision.
What are the signs of Congenital Glaucoma?
- Large eyes
- Cloudy corneas
- Unequal size of eyes
- Constant watery or teary eyes
- Sensitivity to bright lights (‘Photophobic’)
Can Glaucoma be treated?
Yes, Congenital Glaucoma can be treated either medically or surgically. The success of any treatment depends on how early the treatment starts.
Who treats Glaucoma?
A trained Consultant Ophthalmologist with experience in dealing with Congenital Glaucoma should lead the treatment. It’s a condition that requires lifelong monitoring and treatment.
Traditionally, the aim of cataract surgery has been to give patients the quality of vision to ensure a normal lifestyle including distance vision activities such as driving and watching movies. For clear near vision after cataract surgery, patients would often still require glasses for reading.
Nowadays, candidates for cataract surgery have a wide range of options, including multifocal IOLs (Intraocular Lenses) that offer total vision correction.
If you need cataract surgery and want more freedom from spectacles after surgery, then multifocal intraocular lenses are an excellent option to increase your range of clear vision. In fact, many people who choose multifocal intraocular lenses are generally glasses-free or may only need reading glasses occasionally for reading small print, after cataract surgery.
Who are the best candidates for multifocal IOLs?
If you are considering having a multifocal IOL implant, it’s important to understand that they also have their limitations.
If you are in a job that needs you to have the best possible distance vision at all times, or excellent night vision – for example if you are a pilot or someone who does a lot of night driving – then you probably are not a good candidate for multifocal IOL implants and regular monofocal (single-focus) lenses would be a better choice and provide very good distance vision. This would mean that you would need reading glasses to see well, up close.
Another thing to keep in mind is that if you have an associated visual condition other than a cataract (such as diabetic retinopathy, glaucoma or age related macular degeneration), you would be more satisfied with the results using regular monofocal IOLs. This is because multifocal IOLs need good visual capability in both eyes for optimal results.
Other considerations
To get the best visual results with multifocal IOLs, the exact placement of the lens in the eye is very important.
So, a cataract surgeon may also recommend a laser cataract surgery procedure using a femtosecond laser to help ensure accurate positioning of the multifocal IOL and get the best possible results from the lens.
This blog has been contributed by Dr. Luisa Sastre, Consultant Ophthalmologist in Medical Retina and Cataract Surgery.
Diabetes is a significant public health issue across the Gulf region, including the UAE, Saudi Arabia and Kuwait. According to the international diabetes federation, approximately 20.7% of UAE adults are living with diabetes, equating to around 1.25 million adults, or 1 in 6 adults.
Diabetes is a chronic condition that affects how the body absorbs, stores, and utilises sugar from food. When this process is impaired, it leads to hyperglycemia, elevated blood sugar levels. Over time, consistently high blood sugar levels can damage blood vessels and nerves, leading to complications in multiple organs, including the eyes.
One of the most serious eye-related complications of diabetes is Diabetic Retinopathy. Despite its potential severity, it often develops gradually and without noticeable symptoms, making regular eye screenings essential for all individuals living with Diabetes.
In this blog, we explore the connection between Diabetes and vision, explaining the causes and progression of diabetic retinopathy, and provide insights into modern treatment options available.
What are the different types of diabetes?
There are two main types of Diabetes:
- Type 1 Diabetes is typically diagnosed in children or young adults. It is often referred to as “insulin-dependent” Diabetes and results from an autoimmune process where the pancreas produces little or no insulin.
- Type 2 Diabetes is the most common form and primarily affects adults over the age of 40, although it is increasingly seen in younger individuals. It is closely linked to obesity, sedentary lifestyles, and genetic predisposition.
What are the genetic factors of diabetes?
- If one parent has type 2 Diabetes, the child’s risk is approximately 40%.
- If both parents are affected, the risk increases to 70%.
- For type 1 Diabetes, the hereditary risk is significantly lower at around 5%.
What Is Diabetic Retinopathy?
Diabetic Retinopathy is a complication of diabetes that occurs when persistently high blood sugar levels damage the blood vessels of the retina which is the thin, light-sensitive tissue lining the back of the eye.
As the condition progresses, these vessels may swell, leak, or become blocked, resulting in reduced blood flow to the retina. In more advanced stages, abnormal new blood vessels may grow, potentially leading to bleeding, scar tissue formation, and further complications such as retinal detachment.
What leads to diabetic retinopathy?
There are various risk factors that contribute to the development of diabetic retinopathy, which include:
- Duration of diabetes (the longer a person has diabetes, the higher the risk)
- Poor blood sugar control
- High blood pressure
- Elevated cholesterol or lipid levels
- Kidney disease
- Pregnancy (in women with pre-existing diabetes)
What are the symptoms of diabetic retinopathy?
Diabetic Retinopathy often develops silently, without pain or obvious vision changes in the early stages. However, some individuals may experience:
- Blurred or fluctuating vision
- Impaired night vision
- Difficulty transitioning between light and dark
- Spots or dark strings (floaters) in their field of vision
- Partial or total vision loss in advanced cases
It is important to note that good vision does not rule out the presence of diabetic retinopathy. Regular diabetic eye examinations are important even in the absence of symptoms.
How is diabetic retinopathy diagnosed?
A retina specialist uses advanced diagnostic tools to detect and monitor diabetic retinopathy:
- Fundus Examination: A detailed evaluation of the retina using specialised lenses and lighting.
- Optical Coherence Tomography (OCT): A non-invasive imaging scan that captures cross-sectional views of the retina to detect swelling or structural changes.
- Fluorescein Angiography: A dye-based test used to assess blood vessel leakage and identify areas of poor circulation or abnormal growth.
These tests allow for accurate staging of the condition and guide the development of an individualised treatment plan.
What are the different stages of Diabetic Retinopathy?
- Mild Non-Proliferative Retinopathy: Small bulges in blood vessels (microaneurysms) appear.
- Moderate Non-Proliferative Retinopathy: Some blood vessels become blocked.
- Severe Non-Proliferative Retinopathy: More vessels are blocked, cutting off blood supply.
- Proliferative Diabetic Retinopathy (PDR): New, fragile blood vessels grow, which can bleed or cause scar tissue.
Another related condition, Diabetic Macular Oedema (DME), can occur at any stage and involves swelling in the central part of the retina (macula), resulting in blurred central vision.
Treatment Options for Diabetic Retinopathy
Treatment is tailored based on the severity and progression of the disease. Common options include:
- Observation: For early or mild cases, regular monitoring may be sufficient, especially if there are no symptoms or changes in vision.
- Intravitreal Injections: Medications such as anti-VEGF agents or steroids are injected directly into the eye to reduce retinal swelling, stop blood vessel leakage, and prevent new abnormal vessels from growing
- Laser Therapy
- Conventional Laser Photocoagulation: Targets leaking blood vessels or oxygen-deprived retinal areas in severe cases.
- Subthreshold Micropulse Laser: A gentler, more targeted approach that minimises damage to surrounding tissue.
- Subthreshold Micropulse Laser: A gentler, more targeted approach that minimises damage to surrounding tissue.
- Vitrectomy Surgery: In advanced cases involving retinal detachment, dense bleeding (vitreous haemorrhage), or scar tissue, surgery may be necessary to restore vision and prevent further damage.
Importance of early diagnosis for Diabetic Retinopathy
Early diagnosis of diabetic retinopathy significantly improves treatment outcomes and helps prevent permanent vision loss. Annual dilated eye exams are strongly recommended for:
- All individuals with type 1 diabetes (starting within 5 years of diagnosis)
- All individuals with type 2 diabetes (starting at diagnosis)
- Pregnant women with diabetes (ideally before conception and during each trimester)
Consistent control of diabetes, combined with regular eye screening, is the cornerstone of prevention.
Living with Diabetes: Protecting your vision
Maintaining eye health with diabetes requires a comprehensive approach:
- Keep blood sugar, blood pressure, and cholesterol within recommended levels
- Adhere to prescribed medications and treatment plans
- Maintain a healthy diet and stay physically active
- Avoid smoking and limit alcohol consumption
- Prioritise annual eye exams—even if your vision seems fine
Your eye health is closely tied to your overall diabetic management plan. By staying proactive, you can preserve your sight and prevent complications.
Conclusion
Diabetic Retinopathy is one of the leading causes of preventable vision loss in the working-age population. The good news is that with regular monitoring and timely intervention, vision loss can often be slowed, stopped, or even reversed.
At Moorfields Eye Hospital Dubai, our retina specialists provide expert diabetic eye care utilising the latest diagnostic technologies and advanced treatments to ensure each patient receives a tailored management plan.
Frequently Asked Questions (FAQs) about Diabetic Retinopathy
- Can diabetic retinopathy affect both eyes? Yes, diabetic retinopathy commonly affects both eyes. However, the degree of involvement may differ from one eye to the other. It’s not unusual for one eye to show more advanced damage while the other appears to be in an earlier stage. This asymmetry makes it essential for each eye to be evaluated separately during an examination. Since diabetic retinopathy can begin silently, even without noticeable symptoms, routine screenings by an ophthalmologist are critical for both eyes, regardless of how well a person may feel they are seeing.
- How long does it take for diabetic retinopathy to develop? The timeline varies from person to person. In individuals with type 2 diabetes, which often goes undiagnosed for several years, diabetic retinopathy may already be present at the time of diagnosis. In contrast, those with type 1 diabetes typically begin to develop changes in the retina after about five years of living with the condition. However, the onset and severity depend on how well diabetes is controlled. Factors such as persistent high blood sugar, unmanaged blood pressure, and elevated cholesterol levels can accelerate the progression of retinopathy.
- Can diabetic retinopathy be reversed?
Unfortunately, the structural damage caused by advanced diabetic retinopathy such as scarring, retinal detachment, or blood vessel closure is often irreversible. However, if diagnosed in its early stages, diabetic retinopathy can be managed effectively. Treatments like laser therapy, intravitreal injections, and surgical procedures can help preserve the remaining vision and prevent the disease from progressing further. Early detection offers the best chance for stabilising the condition and maintaining quality of life. - Does vision always improve after treatment?
Not always. The goal of treatment is to halt or slow down disease progression. While some patients do experience an improvement in vision, especially if they begin treatment early, others may not experience changes. For instance, if the macula (the central part of the retina responsible for sharp vision) has been affected, recovery may be limited. Nevertheless, stabilising the condition and avoiding further deterioration is a major success, particularly when intervention happens before irreversible damage has occurred. - Can I prevent diabetic retinopathy?
While it is not always possible to completely prevent diabetic retinopathy, its development and progression can be significantly delayed through good diabetes management. Keeping blood glucose levels within the target range, controlling blood pressure and cholesterol, avoiding smoking, staying physically active, and attending regular medical and eye check-ups all contribute to lower risk. People who consistently monitor and manage their diabetes tend to have milder forms of retinopathy and better long-term vision outcomes - How often should I have my eyes checked if I have diabetes? For individuals with diabetes, an annual comprehensive dilated eye exam is recommended. These exams allow ophthalmologists to detect changes in the retina before symptoms arise. If retinopathy is already present or if other risk factors exist such as pregnancy or poor diabetes control more frequent visits may be advised. Regular eye screenings are essential because diabetic retinopathy can develop and progress silently. Proactive monitoring helps ensure that any early signs are addressed before they escalate into vision-threatening complications
This blog on Keratoconus has been contributed by Dr Osama Giledi, Consultant Ophthalmologist, Specialist in Cataract, Cornea and Refractive Vision Correction Surgery
What is Keratoconus?
The word Keratoconus comes from two Greek words: kerato (cornea) and konos (cone). Keratoconus is a degenerative disorder of the eye in which the shape of the cornea, which is usually round, is distorted and develops a cone-shaped bulge, resulting in reduced vision. Keratoconus is a relatively common condition. It affects one person in two thousand, occurs around the world and is quite common in the Middle East.
Progression of Keratoconus depends on the patient’s age at the time of onset and the severity of eye rubbing. The earlier the onset, the faster Keratoconus may progress. The condition always affects both eyes and is asymmetric, so one eye may be more affected than the other.
Causes
Keratoconus has many causes, and it results in a cornea that is more elastic than normal and that starts to thin and bulge forward, causing reduced vision and increased astigmatism. It can be inherited, and a chromosomal link has been identified. Keratoconus can be associated with other allergic diseases such as hay fever, eczema and asthma but we are not born with it, and its onset usually happens around puberty. It is strongly associated with eye rubbing, making it progress rapidly. It is also seen in contact lens wearers.
For the best outcome, Keratconus should be detected and treated early. Early detection is possible by generating computerized corneal shape and thickness measurements through corneal topography using advanced technology such as a pentacam machine. If left untreated, Keratoconus could lead to significant visual impairment and blindness.
Treatment
Spectacles
These can provide good vision in the early stages of the condition and usually help to correct myopic astigmatism.
Hard or Scleral Contact Lenses
When spectacles don’t work, rigid contact lenses and Scleral lenses usually provide very good vision if the patient can tolerate them; they should be fitted by a contact lens specialist.
CXL – Corneal Collagen Cross linking with Riboflavin (Vitamin B2)
This technique increases the strength of the cornea and prevents the progress of Keratoconus.
Intracorneal Rings (Intacs & Ferrara)
These rings inserted into the cornea change the shape of the corneal cone, flattening it and making it a more regular and central shape. This will help improve the vision for the majority of patients.
We use it when patients cannot tolerate contact lenses and while the cornea is still clear and the condition is not very advanced. A Femto-second laser is used to create the tunnel and the entry point for the rings, making it a very safe and reliable procedure.
Toric Implantable Contact Lenses
For those with stable Keratoconus and good vision with glasses, Toric Implantable Contact Lenses are generally used (sometimes after stabilizing the Keratoconus with corneal cross linkage) to improve corneal shape with an intracorneal ring or with very limited therapeutic Excimer laser correction. The Toric ICL can eliminate the need for optical aids altogether and, in some patients, results in improved vision and balance between the two eyes.
Phototherapeutic Keratectomy (PTK)
Keratoconus patients are not candidates for Lasik or normal laser correction. However, some patients benefit from limited excimer laser correction to improve the surface irregularity of the cornea when
contact lenses cannot be tolerated. PTK is always combined with corneal cross-linkage, undertaken during the same procedure or afterwards.
Corneal Transplants
Corneal Transplants are used in the advanced stages of Keratoconus, when there is corneal scarring. The procedure is either a partial thickness (Deep Anterior Lamellar Keratoplasty = DALK) or full thickness graft (Penetrating Keratoplasty = PK). The need for corneal grafts is declining because of the increasing success in the early diagnosis of Keratoconus and the effectiveness of corneal cross linkage to stabilize the condition, so Keratoconus generally does not reach the advanced stage.
This week’s blog on Uveitis has been contributed by Dr Avinash Gurbaxani, Consultant Ophthalmic Surgeon in Uveitis and Medical Retinal Diseases and Cataract Surgery.
Uveitis is not a single disease but a clinical spectrum of symptoms and signs caused by a variety of medical conditions. Although it accounts for about 1% of all eye diseases, Uveitis is the cause of 10-15% of blindness, thus, it must be managed very carefully. Prompt and appropriate treatment is needed to ensure good visual recovery, which is very often achievable. In most cases, a Uveitis specialist – an eye doctor with specialist training in diagnosing and managing these diseases – should manage Uveitis.
Uveitis can affect children, especially those with childhood arthritis or infections. Uveitis affects young adults of a working age and more often women are affected. Symptoms include red eye (although in children the eyes do not become red, so if diagnosed with arthritis, they must have regular screening with the Uveitis specialist), pain, light sensitivity, and blurred vision. It may be associated with skin rashes, joint pains, and stomach symptoms.
Causes:
The cause of Uveitis can be infection (like TB, Toxoplasmosis or viruses like herpes and CMV) or autoimmune conditions (sarcoidosis, arthritis, inflammatory bowel disease). In about half of the cases, we may never find a specific cause but prompt treatment is always needed.
Initially, patients will often need to have a variety of blood tests to look for infection or auto immune conditions, chest x-rays and other imaging. In the eye clinic patients may need an OCT scan of the retina and a flurosein angiogram to look for leakage from the blood vessels in the retina. Patients may also be referred to othzer specialists like rheumatologists, gastroenterologists or neurologist to help diagnose a systemic cause of the Uveitis.
Types and treatment:
Uveitis can be in the anterior segment (front part of the eye), which usually can be treated with drops and sometimes injections to get a quick response. When Uveitis affects the back of the eye, more aggressive treatment may be needed. This usually consists of a high dose of oral steroid medications for several weeks. Antibiotics are given in case of infection. Long-term treatment or more serious cases may need steroid sparing immune suppressant medication. This scan be in the form of tablets like mycophenolate or methotrexate or newer biologic medications, which are given in the form of injections. Steroid injections into the eye may be needed as well. Although protracted, early, aggressive and appropriate treatment can achieve good control of this condition and patients can maintain good vision.
Complications:
Complications of Uveitis include cataract, high pressure in the eye and macular oedema. These may need additional treatment including surgery.
If you have been diagnosed with Uveitis or suspect that you may have Uveitis, it is essential to see a Uveitis specialist