Why Every Diabetic Patient Needs an Annual Eye Exam — And How to Get Referred

If you have been diagnosed with type 1 or type 2 diabetes, you already know that the disease affects many systems in the body. What many patients don't fully appreciate is the serious and silent threat that diabetes poses to vision. Diabetic retinopathy is the leading cause of preventable blindness in working-age adults in Canada — and the most important thing you need to know about it is this: it causes no symptoms until it is advanced. By the time your vision blurs or you notice something is wrong, significant and sometimes irreversible damage may already have occurred. Annual dilated eye exams exist precisely to catch and treat retinopathy before that happens.

What Is Diabetic Retinopathy?

The retina is the light-sensitive tissue lining the back of the eye — it is where the visual image is formed before being transmitted to the brain via the optic nerve. The retina requires a constant supply of oxygenated blood, delivered through a network of tiny capillaries. Chronically elevated blood glucose damages these capillaries in several ways: it weakens their walls, causing them to bulge (microaneurysms) and leak fluid or blood (haemorrhages). In response to poor circulation, the retina may generate new abnormal blood vessels in a process called neovascularisation — but these new vessels are fragile and prone to bleeding into the vitreous (the gel-like interior of the eye) or pulling on the retina, risking retinal detachment.

The two main stages of diabetic retinopathy are:

• Non-proliferative diabetic retinopathy (NPDR): Earlier stage, characterised by microaneurysms, retinal haemorrhages, and exudates. Vision may not yet be affected, but monitoring and often treatment are important to prevent progression.
• Proliferative diabetic retinopathy (PDR): More advanced stage, marked by neovascularisation. At risk of vitreous haemorrhage, tractional retinal detachment, and rapid vision loss. Requires prompt treatment.

Diabetic macular oedema (DME) can occur at any stage and involves leakage of fluid into the macula — the central retina responsible for reading vision and fine detail. DME is one of the most common causes of vision loss in people with diabetes and requires specific treatment.

Why This Matters Especially in the Fraser Valley

The Fraser Valley has one of the most diverse and rapidly growing South Asian communities in British Columbia. This is clinically significant because individuals of South Asian descent — including those of Indian, Pakistani, Bangladeshi, and Sri Lankan heritage — have substantially higher rates of type 2 diabetes compared to people of European descent. Studies show that South Asian individuals develop type 2 diabetes at a younger age, at lower body weights, and with a higher degree of insulin resistance. As a result, South Asian patients in the Fraser Valley face disproportionately high rates of diabetic retinopathy and are at risk of developing it earlier in their diabetic history than the general population guidelines might suggest.

This is one of the reasons Dr. Sundaram's practice places particular emphasis on diabetic eye screening — ensuring that patients across Abbotsford, Chilliwack, Mission, and the broader Fraser Valley have access to timely assessment, regardless of how long they have had their diagnosis.

How to Ask Your GP for a Referral

In BC, a diabetic eye exam — a dilated fundus examination — can be performed by both optometrists and ophthalmologists. Canadian Diabetes Association guidelines recommend that all patients with type 1 diabetes undergo annual dilated eye exams beginning five years after diagnosis, and all patients with type 2 diabetes begin annual exams at the time of diagnosis (since many patients have had undetected diabetes for years before diagnosis).

If you have diabetes and have not had a dilated eye exam in the past year, the next step is straightforward:

1. At your next appointment with your family doctor, mention that you have not had a diabetic eye exam recently and ask for either an optometry referral (for routine screening) or an ophthalmology referral (if there is concern about retinopathy already, or if you have poor blood sugar control, long duration of diabetes, hypertension, or kidney disease — all of which accelerate retinopathy).
2. Provide your family doctor with your current HbA1c, blood pressure readings, and duration of diabetes — this information helps the optometrist or ophthalmologist assess your risk level and prioritise your appointment.
3. If you have symptoms such as blurred vision, floaters, dark spots, or sudden vision loss, you should not wait for a routine appointment — ask for an urgent ophthalmology referral and have your GP note the urgency clearly on the referral.

What the Diabetic Eye Exam Involves

A diabetic eye exam is different from a standard vision check. The key component is a dilated fundus examination — your eyes will be dilated with drops (this takes 20–30 minutes), and the ophthalmologist will use a slit lamp and ophthalmoscope to carefully examine the retina, macula, optic nerve, and blood vessels of both eyes in detail.

In addition to the dilated exam, Dr. Sundaram may recommend:

• Optical Coherence Tomography (OCT) of the macula: A non-invasive scan that detects and quantifies fluid in the macula with very high sensitivity. This is the primary tool for detecting and monitoring diabetic macular oedema.
• Fundus photography: Retinal photographs provide a permanent record of your retinal appearance, allowing precise comparison year over year to detect subtle changes.
• Fluorescein angiography (if indicated): A dye-based imaging test used when neovascularisation or significant vascular leakage is suspected. Not required routinely but very useful in assessing proliferative retinopathy.

Treatment If Retinopathy Is Found

The right treatment depends on the type and stage of retinopathy found:

Optimising Systemic Control

For early or mild NPDR without macular oedema, the most important intervention is optimising blood sugar control (HbA1c), blood pressure, and cholesterol — working closely with your family doctor or endocrinologist. Every percentage point improvement in HbA1c meaningfully reduces the risk of retinopathy progression.

Anti-VEGF Injections

Anti-VEGF (anti-vascular endothelial growth factor) injections, administered directly into the vitreous of the eye, are the current first-line treatment for diabetic macular oedema and are also used for proliferative diabetic retinopathy. These medications (such as ranibizumab, aflibercept, or bevacizumab) block the abnormal blood vessel growth and leakage driven by VEGF. Multiple injections are typically required, with frequency tapering as the condition responds to treatment. These injections are performed in clinic under local anaesthesia and are covered by BC PharmaCare for eligible patients.

Laser Treatment (Pan-Retinal Photocoagulation)

For proliferative diabetic retinopathy, laser photocoagulation of the peripheral retina (pan-retinal photocoagulation, or PRP) reduces the drive for neovascularisation by treating ischaemic retina. While it remains an important tool in advanced retinopathy, anti-VEGF injections are now often preferred as initial treatment where available.

Vitrectomy Surgery

In cases of non-clearing vitreous haemorrhage or tractional retinal detachment, surgical removal of the vitreous gel (vitrectomy) may be required. This is performed under general or local anaesthesia in a hospital setting.

For family physicians and referring practitioners in the Fraser Valley, detailed referral information and co-management protocols are available on our For Physicians page.