Retinal disorders: When diseases of the retina start stealing your sight

Vision can change in ways that are easy to dismiss. Words on a page may become blurry, straight lines may appear bent, colours may look faded or black spots may begin floating across what a person sees.

For some people, these changes may signal a problem with the retina, the thin layer at the back of the eye that receives light and sends signals to the brain, allowing us to see.

Retinal disorders are a group of conditions that affect this important part of the eye. They can develop for different reasons, including diabetes, ageing, premature birth, problems with the blood vessels supplying the eye or injuries.

Dr Mahesh Chandargi, a neuro-ophthalmology consultant eye surgeon, says retinal disorders are part of his everyday work.

“Retinal disorders, retinal conditions are not once in a while. It is an everyday affair for me.”

Among the conditions he encounters are diabetic retinopathy, age-related macular degeneration (AMD), retinal vein occlusion, retinopathy of prematurity (ROP), retinal detachment and macular holes.

Diabetes and the retina

Diabetes is one of the important conditions linked to retinal damage.

Dr Chandargi says diabetic retinopathy develops when prolonged high blood sugar damages the tiny blood vessels supplying the retina. The vessels can leak or become blocked, while abnormal blood vessels can grow in advanced disease and bleed into the eye. This can damage vision and, if untreated, lead to permanent sight loss.

The condition can be particularly difficult to detect because a person may have retinal damage without noticing any change in their vision.

Kenya has a sizeable population at risk. The International Diabetes Federation estimates that 813,300 adults in Kenya were living with diabetes in 2025, equivalent to 3.1 per cent of the adult population. It estimates that 53.6 per cent of diabetes cases in the country were undiagnosed.

A systematic review and meta-analysis of studies from East Africa found that about 28 per cent of adults with diabetes had diabetic retinopathy. For Kenya, the pooled estimate was 22 per cent, although the researchers noted differences between studies and populations.

Dr Chandargi says eye health can easily become an afterthought for someone managing diabetes.

People may focus on controlling their blood sugar, taking medication and managing their diet while overlooking their eyes until their vision starts changing.

Another condition linked to diabetes is diabetic macular oedema (DME).

The macula is the central part of the retina responsible for sharp, detailed vision. When damaged blood vessels allow fluid to collect around the macula, it can swell and affect central vision. A person may notice that objects look blurred or that straight lines appear bent or wavy. Colours may also appear faded.

When this swelling is caused by diabetic retinopathy, it is known as diabetic macular oedema.

Treatment can include injections into the eye, laser treatment or, in some cases, surgery, depending on the cause and severity.

Ageing eyes

Retinal disorders are not limited to people with diabetes. As people grow older, they become more vulnerable to age-related macular degeneration, commonly known as AMD. The condition affects the macula and mainly interferes with central vision, which is needed for tasks such as reading and recognising faces.

Dr Chandargi estimates that AMD accounts for about 10 to 12 per cent of patients in his retina clinic.

The World Health Organisation says the risk of AMD increases with age. The condition can cause dark patches, shadows or distortion in central vision.

A person may notice that straight lines appear wavy or that the centre of what they are looking at seems distorted.

When the patient is a newborn

There is also a retinal disorder that can affect babies born too early. Retinopathy of prematurity, or ROP, occurs when the blood vessels supplying the retina have not completed their normal development because a baby was born prematurely.

Dr Chandargi says these babies need retinal screening because untreated ROP can result in blindness.

Advances in newborn care mean more very premature babies are surviving, making appropriate eye screening increasingly important.

ROP is not the same condition as diabetic retinopathy. Both affect the retina, but they have different causes and affect very different groups of patients.

Warning signs of retinal disease

Some retinal disorders develop gradually, while others can cause sudden vision changes. Dr Chandargi says symptoms may include blurred vision, black spots, sudden loss of sight or a sensation that a curtain has come across the eye

“Early detection and treatment are critical,” he says, “because there is a window in which treatment can prevent further damage and preserve vision.”

Treatment depends on the particular retinal condition. Dr Chandargi says options can include injections, laser treatment and surgery.  Some patients require repeated treatment, scans and follow-up rather than a single procedure.

The challenge is that some patients delay seeking care because of financial difficulties, distance or simply because they do not realise their eyes are at risk.

Screening can identify disease before significant vision loss occurs. For people living with diabetes, regular eye examinations are particularly important because diabetic eye disease can develop before symptoms appear.

For Dr Chandargi, the priority is to catch retinal disease early. The retina may be hidden at the back of the eye, yet when it begins to fail, the effects can be felt in almost every part of daily life. Early screening, timely treatment and continued follow-up can give patients a better chance of preserving their sight.