Macular Degeneration
Macular Degeneration is one of the top three blindness-causing eye diseases in the world. It is estimated that there are more than 190 million people with macular degeneration worldwide, and one in ten of them will lose their eyesight permanently as a result. With an ageing population, the number of people with the disease is expected to exceed 280 million by 2040.1.
Macular degeneration is usually seen in people over the age of 50. However, with the popularity of electronic products and excessive eye use in recent years, there is a trend towards a younger age group. It is common for people's eyes to deteriorate and age prematurely. Macular degeneration is an eye disease that happens with there is damage to the macula.
Symptoms of macular damage include decreased visual acuity, distortions in the appearance of lines, etc. The disease is usually caused by the ageing and deterioration of eye function. Delayed detection and treatment can lead to blindness.
1 Source: Ophthalmology and Visual Sciences, The Chinese University of Hong Kong
What is Macular Degeneration?
The macula is the central portion of the retina where 90% of photoreceptors are concentrated. It is responsible for focusing central vision in the eye, and it controls our ability to read, drive a car, write, recognize faces or colours, and see objects in fine detail. So it is important to keep your macula healthy in order to see clearly. Macular degeneration is an eye disease that happens when there is damage to the macula. Symptoms of macular damage are decreased visual acuity, distortions in the appearance of lines and darkening of the central vision. The disease is usually caused by the ageing and deterioration of eye function.
Types of Macular Degeneration
Dry type
Macular Degeneration
Wet type
Macular Degeneration
Causes of Macular Degeneration
Family history
Ageing
黃斑退化
Excessive
sun exposure
(Ultraviolet)
Smoking
Eating lots of high fat
or cholesterol food
High myopia
Symptoms of Macular Degeneration
Darkness in the centre
of your vision
Blurred vision
Visual distortion
Simple Self-Diagnosis
Simple Self-Diagnosis
Amsler Grid
A simple test for macular degeneration
- Hold the grid 30 cm from your eyes, looking at the centre with one eye
- Repeat the same step again to test the other eye
- During the test, if gaps or distortions are seen in the straight lines, or some area appears blurred, you may have signs of possible intraocular problems
- In addition to these common symptoms, patients may also experience night blindness
Be aware of the following symptoms
Distortion
Dark spot
Blurred central vision
Treatments
Intravitreal Anti-VEGF Injection
玻璃體注射(眼內注射藥物)
The intravitreal injection stops the growth of new blood vessels, thus reducing neovascular leakage and bleeding. Not only can the intraocular condition be controlled, but the impaired vision can also be improved. Patients are required to receive the injection within a specified period of time and under sterile and surface anaesthetic conditions.
Laser photocoagulation
Laser photocoagulation uses high-energy laser light to destroy an abnormal growth of blood vessels in the retina to stop their proliferation and reduce leakage, bleeding and oedema, preventing vision loss. The treatment takes effect indiscriminately in the eye and has the potential to damage the surrounding healthy tissues, causing visual impairment. Therefore, it is only suitable for patients whose lesions are located far from the centre of the macula.
Photodynamic therapy
The doctor will conduct an intravenous injection with a light-sensitive medicine which will be absorbed by the abnormally-grown blood vessels. The medicine will then be activated to block the abnormal blood vessels by special laser light, controlling the deterioration of this disease and improving the patient’s visual function. This treatment does not cause damage to peripheral tissues and is beneficial in improving vision degeneration.
Dr. YEUNG Tak Yee is one of the designated doctors under the "Anti-VEGF Medicine Subsidy Scheme" jointly organised by Retina Hong Kong and the Hong Kong Health Care Alliance. The scheme provides financial assistance to designated eye clinic patients* currently waiting in public hospitals. Patients can save the time of waiting by visiting the designated doctor's clinic for anti-VEGF medicine. Patients in need of anti-VEGF medicine can come to our centre by appointment through the Hong Kong Health Care Alliance.
*They are Anti-VEGF therapy patients who are diagnosed with wet age-related macular degeneration, diabetic macular oedema, retinal vein occlusion or choroidal neovascularisation. Details of the scheme can be foundhere.
Macular Degeneration FAQ
Why does severe sunburn in the eyes cause macular degeneration?
The UVA from sunlight’s UV radiation have a lower energy level but is more penetrating. The energy can accelerate the ageing of photoreceptors in the retina, causing early damage to the posterior macula and its degeneration.
Can macular degeneration cause total blindness?
There is a chance of it. When new blood vessels or exudates take over the macula, they can damage the photoreceptors and eventually lead to loss of central vision.
How do I know if my macular degeneration is getting worse?
- If straight lines appear to become wavy or the mild waviness have worsen and image become distorted
- If there is a central or near-central darkened area of vision
- If there is a sudden blockage or blackened area in or near the central vision