What is a cataract?

A cataract occurs when the lens of the eye becomes cloudy or opaque.

What symptoms does a cataract cause?

Cataracts cause general blurring of vision. They may also cause glare, difficulty driving at night and increased short-sightedness.

Why does it occur?

Most cataracts occur due to aging. They can also occur following trauma, inflammation in the eye (uveitis), and following vitrectomy surgery.

How is it diagnosed?

Cataracts can be diagnosed by clinical examination on a slit lamp.

What is the management?

If a cataract is affecting your vision, it may need to be treated. The only effective treatment is cataract surgery, which is performed as a day procedure at a hospital. The cataract is removed and replaced by a clear plastic intraocular lens which will stay in your eye for the rest of your life. Associate Professor Fung has access to the latest technology for calculating the correct power of your individualised intraocular lens and expertly performing your surgery. Speak to him in more detail during your visit.

What is a choroidal naevus and melanoma?

A choroidal naevus is a benign (non-harmful) “mole” that can lie underneath your retina. It is quite common, with approximately 1 in 20 people having a choroidal naevus. A choroidal melanoma is much more rare, and has the potential to affect vision and spread to the rest of the body.

What symptoms does a choroidal naevus and melanoma cause?

Choroidal naevi do not usually cause symptoms. Choroidal melanoma may not cause symptoms, or may be associated with flashing lights and blurred vision.

Why does it occur?

No one fully understands why choroidal naevi and melanoma occur, however genetics plays an important part in their development.

How is it diagnosed?

Choroidal naevi and melanoma can be diagnosed by a combination of clinical examination and investigations including optical coherence tomography (OCT) scans, fundus autofluorescence and B-scan ultrasonography.

What is the management?

Choroidal naevi can be observed. Choroidal melanoma require treatment, which may include a radioactive plaque on the outside of the eye (brachytherapy) or removal of the eye (enucleation). Speak to Associate Professor Fung at your visit for more advice.

What is diabetic retinopathy?

Diabetic retinopathy is a vessel disease caused by diabetes (high sugars in the bloodstream).

What symptoms does diabetic retinopathy cause?

Diabetic retinopathy can affect the vision in two main ways: swelling of the macula (macular oedema), or bleeding into the vitreous jelly of the eye (vitreous haemorrhage). Macular oedema may cause blurred vision, a central black spot in the vision, distortion and/or difficulty with depth perception. Vitreous haemorrhage may cause a cloud of spots floating in your vision “floaters” or loss of vision.

Why does it occur?

The high sugar levels in the bloodstream adversely affect the blood vessel walls, causing leaking and macular oedema. Vitreous haemorrhage occurs because abnormal blood vessels grow in the eye.

How is it diagnosed?

Diabetic retinopathy can be diagnosed by clinical examination. An optical coherence tomography (OCT) scan or fluorescein angiogram may need to be performed.

What is the management?

Firstly, the underlying cause such as diabetes and high blood pressure will need to be addressed. Associate Professor Fung may need to liase with your general practitioner. Your eye might need treatment, depending on the severity of the diabetic retinopathy. Those associated with macular oedema may need treatment with intravitreal injections such as Ranibizumab (Lucentis^®) or Aflibercept (Eylea^®). Sometimes laser surgery is prescribed for abnormal blood vessels and vitreous haemorrhage. More severe cases of vitreous haemorrhage or tractional retinal detachment require vitrectomy surgery.

What is an epiretinal membrane?

An epiretinal membrane is a membrane or scar tissue that can grow on the surface of the retina, usually at the macula

What symptoms does an epiretinal membrane cause?

An epiretinal membrane can cause blurred vision, a central black spot in the vision, distortion and/or difficulty with depth perception.

Why does it occur?

Most epiretinal membranes occur due to aging. Other causes include retinal vessel blockages, retinal tears or detachment, diabetes, inflammation in the eye (uveitis) and blood vessels growing at the back of the eye (choroidal neovascularisation).

How is it diagnosed?

Epiretinal membranes can be diagnosed by clinical examination and optical coherence tomography (OCT) scans.

What is the management?

Milder cases of epiretinal membrane can be observed. More severe cases which are affecting vision may need vitrectomy surgery in a hospital to prevent further loss of vision. This involves key-hole surgery through the white part of the eye (sclera). The vitreous jelly and the epiretinal membrane on the surface of the retina are removed. For further details, see vitrectomy surgery. Speak to Associate Professor Fung at your visit for more advice.

What is a macular hole?

A macular hole is a circular hole that occurs at the macula, the centre of the retina. It differs from macular degeneration.

What symptoms does a macular hole cause?

A macular hole can cause blurred vision, a central black spot in the vision, distortion and/or difficulty with depth perception.

Why does it occur?

Most macula holes occur due to aging, as the vitreous separates from the retina. Occasionally they can be associated with short-sightedness (myopia) or trauma.

How is it diagnosed?

Macula holes can be diagnosed by clinical examination and optical coherence tomography (OCT) scans.

What is the management?

Most full-thickness macular holes won’t improve by themselves, so vitrectomy surgery in a hospital is advised in most cases. This involves key-hole surgery through the white part of the eye (sclera). the vitreous jelly and a thin membrane on the surface of the retina are removed. A gas bubble is then inserted into the eye, which usually will dissolve by itself over approximately 3 weeks. After the operation you may be asked to sit-up and look down as if reading for a few days. Whilst the gas bubble is in your eye you cannot fly on an aeroplane or go to high altitudes. Macular hole surgery is very successful, with an average closure rate for the hole of over 95% in most cases. For further details, see vitrectomy surgery. Speak to Associate Professor Fung at your visit for more advice.

What is Pathological Myopia?

Myopia refers to short-sightedness (the ability to see well for short distances such as reading, but not for long distances such as when driving). This is usually due to the eyeball being longer than normal. If the myopia is severe enough to cause changes to eye structures, this is known as pathological myopia. Pathological myopia comprises of several conditions, including:

1. Changes to the optic nerve including glaucoma
2. Posterior staphyloma (out-pouching of the back of the eye)
3. Macular hole
4. Epiretinal membrane
5. Vitreomacular traction syndrome
6. Splitting of the retina (retinoschisis)
7. Bleeding at the back of the eye (choroidal neovascularisation)
8. A higher risk of retinal tears and detachment

What symptoms does pathological myopia cause?

This depends on how the myopia is affecting your eye, but may include blurred vision, a central black spot in the vision, distortion and/or difficulty with depth perception.

Why does it occur?

No-one fully understands why myopia occurs. We know that it is becoming increasingly common, particularly in Asian populations. There is a combination of genetic (family history) and environmental causes. Researchers now believe that exposure to outdoor activity and sunlight at a childhood age can help slow the progression of myopia.

How is it diagnosed?

How short-sighted (myopic) you are can be determined by readings of your eyes and/or spectacles. Determining if you have pathological myopia will depend on clinical examination. Often further investigations will be required, and may include optical coherence tomography or fluorescein angiography.

What is the management?

This depends on the condition. Click on the above conditions to find out more, or speak to Associate Professor Fung when you see him at the clinic.

What is a posterior vitreous detachment (PVD)?

A PVD occurs when the vitreous separates off from the retina. It is very different to a retinal detachment, which is more serious.

What symptoms does a PVD cause?

A PVD may occur without symptoms, or may be associated with flashing lights or a cloud of spots floating in your vision “flashes and floaters”.

Why does it occur?

Most of the time PVDs occur due to aging. In fact, it is quite common to have a PVD by the age of 60 or 70 years. Only a minority of PVDs are caused by trauma.

How is it diagnosed?

PVDs can be diagnosed by clinical examination. Often an optical coherence tomography (OCT) scan can assist in the diagnosis.

What is the management?

Associate Professor Fung will examine your eye to ensure there is retinal tear or detachment, which can be associated with a PVD. If the PVD is not associated with a retinal tear or detachment. no specific treatment other than observation is required. In most cases the “flashes and floaters” will diminish over weeks, but not necessarily completely dissipate.

What is a retinal detachment?

Retinal detachment occurs when the retina separates off from the inside wall of the eye. In most cases it is caused by a retinal tear.

What symptoms does a retinal detachment cause?

Retinal detachment can cause blurred vision, a shadow in the vision, flashing lights or a cloud of spots floating in your vision “flashes and floaters”.

Why does it occur?

Most of the time retinal detachments occur due to aging. People who are short-sighted (myopic) are more likely to develop a retinal detachment since their retina are thin. Unlike what many people believe, only a minority of tears are caused by trauma or excessive exertion.

How is it diagnosed?

Retinal detachment can be diagnosed by clinical examination.

What is the management?

In most cases urgent surgery is required. The urgency depends on the configuration of the detachment, but can range from surgery the same day to one week later.

The most common surgery is vitrectomy surgery. This involves key-hole surgery through the white part of the eye (sclera).The vitreous jelly is removed and the retina is sealed back onto the eye wall with laser. The eyeball is then filled with a substance to keep the retina in place. Options include gas, silicone oil or heavy liquid. After the operation you may be asked to position your head in a certain direction for a few days. If a gas bubble has been placed in your eye you will not be allowed to fly on an aeroplane or go to high altitudes until this has dissolved. How much sight you will get back depends on how severe the retinal detachment is. For further details, see vitrectomy surgery.

Another operation performed for retinal detachment is a scleral buckle. This is a plastic band that wraps around the eye, supporting the wall of the eye against the retina.The buckle is meant to stay in place around your eye for the rest of your life (it will not usually be visible).

There are many factors that determine which is the best operation for your retinal detachment- Associate Professor Fung will discuss what he believes is the best option for your eye.

What is a retinal tear?

A retinal tear occurs when there is a break in the retina. If left untreated, this can lead to a retinal detachment if fluid seeps under the retina and lifts it off.

What symptoms does a retinal tear cause?

Although some tears may not cause symptoms, many tears will cause you to see flashing lights or a cloud of spots floating in your vision “flashes and floaters”.

Why does it occur?

Most of the time retinal tears occur due to aging. People who are short-sighted (myopic) are more likely to develop a retinal tear since their retina are thin. Unlike what many people believe, only a minority of tears are caused by trauma or excessive exertion.

How is it diagnosed?

Retinal tears can be diagnosed by clinical examination.

What is the management?

Most retinal tears require treatment so that they don’t progress to a retinal detachment, which is even more serious. There are two main forms of treatment, both of which are designed to encircle and seal off the tear. In most cases they can be performed in the clinic, although occasionally it needs to be performed in an operative theatre in a hospital:

Retinal (argon) laser

This is a laser that is applied either at a slit lamp with a special contact lens or through a headlamp (indirect ophthalmoscope).

Cryotherapy

This is a freezing probe that is applied to the outside of your eye. The freezing penetrates through to the tear, causing a scar tissue which demarcates it.

Speak to Associate Professor Fung at your visit for more advice. If your symptoms worsen at any time, you must see him as soon as possible.

What is Vitreomacular Traction (Syndrome)?

Vitreomacular traction occurs when the vitreous jelly in the centre of the eye dehydrates and contracts, pulling on the macula at the centre of the retina.

What symptoms does vitreomacular traction cause?

Vitreomacular traction can cause blurred vision, a central black spot in the vision, distortion and/or difficulty with depth perception.

Why does it occur?

Most of the time vitreomacular traction occurs due to aging as the vitreous dehydrates and contracts.

How is it diagnosed?

Vitreomacular traction can be diagnosed by clinical examination and optical coherence tomography (OCT) scans.

What is the management?

Milder cases of vitreomacular traction can be observed. More severe cases which are affecting vision may need intervention. This might include injection of a medication (ocriplasmin) into your eye, or vitrectomy surgery in a hospital to prevent further loss of vision.Vitrectomy surgery involves key-hole surgery through the white part of the eye (sclera) to remove the vitreous jelly. For further details, see vitrectomy surgery Speak to Associate Professor Fung at your visit for more advice.

What is a vitreous haemorrhage?

A vitreous haemorrhage occurs when there is bleeding into vitreous jelly of the eye.

What symptoms does a vitreous haemorrhage cause?

Small vitreous haemorrhages will cause a cloud of spots floating in your vision “floaters”. Larger vitreous haemorrhages can block the entire vision in the affected eye.

Why does it occur?

There are many causes for a vitreous haemorrhage, including:

1. Diabetes
2. Retinal tear and detachment
3. Retinal vein blockages

How is it diagnosed?

Vitreous haemorrhage can be diagnosed by clinical examination. If the view to the back of your eye is poor, Associate Professor Fung will perform an B-scan ultrasound on your eye to ensure that the retina is still attached.

What is the management?

Milder cases of vitreous haemorrhage may be able to be observed with the hope that the blood will clear itself with time. More severe cases may require vitrectomy surgery to clear the blood. The underlying cause for the vitreous haemorrhage will need to be addressed. Speak to Associate Professor Fung at your visit for more advice.