What is diabetic retinopathy?

Diabetic retinopathy (DR) is a complication of diabetes that affects the back of the eye. When someone has high and varying blood sugar levels, the blood vessels in the retina can become irreversibly damaged. This can lead to loss of vision and eventually blindness.

How can you tell if diabetes is affecting your eyes?

Diabetic retinopathy commonly occurs in both eyes and most often starts with no visual symptoms. In the early stages, the walls of the blood vessels in the retina weaken. This can cause fluid and blood to leak into the eye, which sometimes results in blurred vision. Some other symptoms which could develop later include fluctuating vision, double vision, floaters, and impaired colour vision. Diabetes can also cause other eye conditions such as cataract and glaucoma.

What are the stages of diabetic retinopathy?

There are four stages of diabetic retinopathy: Mild Nonproliferative Retinopathy, Moderate Nonproliferative Retinopathy, Severe Nonproliferative Retinopathy and Proliferative Retinopathy.

Can lowering blood sugar level help with diabetic retinopathy?

When blood sugar levels are consistently high, the chances of diabetic retinopathy developing are high. That is why it is important to control your blood sugar levels in order to slow down diabetic retinopathy’s progression to vision loss.

What is the cure for diabetic retinopathy?

While diabetic retinopathy can not be cured, treatments can help prevent or delay vision loss for anyone who has diabetes. For people with diabetes, it is critical to receive regular eye examinations as early detection and treatment can help prevent vision loss. These eye health examinations should be done annually or every two years at a minimum by an eye care practitioner.

5 frequently asked questions about IOLs

The intraocular lens (IOL) has been integral in helping The Fred Hollows Foundation restore sight. Fred Hollows helped revolutionise the production of IOLs, making them affordable and accessible in developing countries like Eritrea, Nepal and Vietnam.

Here are 5 frequently asked questions about IOLS

COVER PHOTO: Anthony Weate/Newspix

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What is an intraocular lens?
What is the purpose of an intraocular lens?
What are the different types of intraocular lenses?
How long does an intraocular lens last?
How does an intraocular lens stay in place?

1. What is an intraocular lens?

An intraocular lens is a small but mighty tool used by The Foundation to restore and improve sight.

The natural lens in the eye becomes cloudy as we age or if the eye is injured. This cloudiness in the lens is called a cataract. When someone has a cataract, things will look blurred and hazy. With cataract surgery, this cloudy lens can be removed and replaced with a clear artificial lens called an intraocular lens (IOL) to restore vision.

When Fred first began his vision of ending avoidable blindness, IOLs were expensive. However, Fred put the pieces in place to create state-of-the-art intraocular lens factories in Nepal and Eritrea. Low cost IOLs from these factories have played a significant role in making affordable cataract surgery possible in low- and middle-income countries.

Modern IOLs are so advanced that they are foldable and inserted through a small incision. This means recovery from eye surgery is quick and efficient. Now, more people than ever can access cataract surgery.

2. What is the purpose of an intraocular lens?

IOLs is most commonly used for vision restoration in cataract surgery. It is rarely used to correct high amounts of myopia (short-sightedness).

IOLs were first used in 1949, early versions caused a lot of complications. Advances in the 1970s yielded better results, with IOLs gaining popularity as a safe way to restore sight. Prior to this, people had to wear thick glasses or strong contact lenses to restore their sight after cataract surgery. The use of IOLs was ground-breaking as it meant that normal glasses could be worn post-surgery as required to restore sight fully. IOLs is most commonly used for vision restoration in cataract surgery. It is rarely used to correct high amounts of myopia (short-sightedness).

IOLs were first used in 1949, early versions caused a lot of complications. Advances in the 1970s yielded better results, with IOLs gaining popularity as a safe way to restore sight. Prior to this, people had to wear thick glasses or strong contact lenses to restore their sight after cataract surgery. The use of IOLs was ground-breaking as it meant that normal glasses could be worn post-surgery as required to restore sight fully.

Photographer: Michael Amendolia

3. What are the different types of intraocular lenses?

Just like glasses, there are a range of lens used in IOLs to meet the needs of each patient.

Aspheric

These are designed to mimic the shape of the natural lens inside the eye. Our natural lens is not a perfect spherical shape - hence why these IOLs are referred to as aspheric. As these lenses closely mirror the shape and quality of our eye's natural lens, they provide clearer vision.

Toric

Astigmatism arises when the refracting surface of the eye, usually the cornea, is more curved in one direction than the other (shaped more like a rugby ball than a spherical basketball). This results in blurred vision. Toric IOLs can be used to correct the blurred vision caused by this astigmatism.

Monofocal

These are the most common type of IOLs used, particularly in cataract surgery. The lens selected is usually focused for distance vision. This means that glasses are still needed for near distance tasks such as sewing, reading or using the computer.

Multifocal

Multifocal lenses have the most versatility as they can work to cover a range of distances.

4. How long does an intraocular lens last?

The best part about IOLs is that they can last for a person’s entire lifetime!

Sometimes the lens may need to be replaced if it does not adequately restore vision, however this is a rare occurrence. The artificial nature of IOLs mean that unlike our eyes they will not break down and age.

5. How does an intraocular lens stay in place?

While it is unlikely, IOLs can fall out of place. The IOL is often inserted during cataract surgery into the eye's capsular bag, a sack-like structure that once housed the clouded lens. This ensures that the lens can stay in place.

However, from trauma to the eye, or diseases that affect the stability of the capsular bag the lens can begin to shift. In instances like these, the lens is usually removed and place in a more secure position.

Despite its small size, the intraocular lens is a piece of plastic that's so important to our work that we use it in our logo. This amazing device is the reason that The Foundation can continue to make cataract surgery affordable and accessible to people around the world.

Photographer: Michael Amendolia

Learn more:

Find out what to expect at an eye test
See what questions you should be asking your doctor
5 frequently asked questions about cataract
Read about nutrients that are good for your eye health

DISCLAIMER:

The content on this page is not intended to be medical advice. For specific medical advice, please contact your health professional.

ABOUT THE AUTHOR

Dr May Ho - The Fred Hollows Foundation

Dr May Ho is the Optometry and Primary Care Adviser at The Fred Hollows Foundation. She is an Australian registered optometrist with over 30 years of public health and international eye health experience. She has worked extensively in the development and implementation of sustainable eye care and education programs in various countries in the Asia Pacific and Africa regions as well as in Haiti and Moldova. She was involved in the development and delivery of refraction, low vision, primary eye care and training of trainers’ courses for various cadres of health workers including mid-level ophthalmic personnel, optometrists, and ophthalmologists. Her biggest achievement is the introduction of the profession of optometry into Vietnam.

5 FREQUENTLY ASKED QUESTIONS ABOUT INTRAOCULAR LENSES