Skip to Content

Diabetes is Silently Destroying the Eyes of 77 Million Indians. Most Don't Know It's Happening.

9 April 2026 by
Diabetes is Silently Destroying the Eyes of 77 Million Indians. Most Don't Know It's Happening.
AGAAZ OPHTHALMICS, Girish Dave
Diabetes is Silently Destroying the Eyes of 77 Million Indians. Most Don't Know It's Happening. | Agaaz Ophthalmics
Beyond Vision · Diabetic Eye Disease · April 2026

Diabetes is Silently
Destroying the Eyes
of 77 Million Indians. Most don't know it's happening.

Diabetic retinopathy causes no pain. No warning. No blurred vision until damage is catastrophic. And 98% of the blindness it causes is completely preventable — if anyone bothers to look.

77MIndians with
diabetes right now
98%Of DR blindness
is preventable
13.6%Of sight-threatening
cases actually treated
The Stakes

There is a specific kind of cruelty in diabetic retinopathy. It gives no warning. A person can have significant, progressive damage occurring at the back of their eye — blood vessels leaking, microaneurysms forming, new abnormal vessels beginning to grow — while their vision reads 20/20 on every chart. By the time they notice something is wrong, the window for easy, effective treatment has very often closed.

India has 77 million people with diabetes. One in five Indian adults now has the disease. Projections put that number at 125 million by 2045. The Indian Journal of Clinical and Experimental Ophthalmology, in its 2025 editorial, described diabetic retinopathy as a rising tide — a condition that has gone from a secondary concern to one of the most urgent public health problems in Indian ophthalmology.

The arithmetic of this crisis is almost unbearable. Sight-threatening diabetic retinopathy affects 5–7% of all diabetics in India — 3 to 4.5 million people right now, today. Up to 98% of the blindness this causes can be prevented with annual screening and timely treatment. Yet the AIIMS National Survey found that of all identified sight-threatening DR cases, only 13.6% had been treated with laser. That gap — between what is preventable and what is actually prevented — represents millions of lives altered by blindness that should never have happened.

🔴

The central paradox of this crisis

73.5% of diabetic patients in India have never had a dilated fundus examination for DR — despite 79% of them knowing that diabetes can damage their eyes. The problem is not ignorance. It is the gap between knowing and acting. Annual screening is the single most powerful intervention available, and most people who need it are not getting it.

Layer 1 — Biology

How high blood sugar destroys retinal vessels

The retina is the most metabolically demanding tissue in the human body per unit weight. It requires a constant, precisely regulated supply of oxygen and glucose delivered by an intricate network of capillaries — some of the smallest blood vessels in the body. These capillaries are the first casualties of chronic hyperglycaemia.

The mechanism begins with advanced glycation end-products (AGEs) — proteins and lipids that become chemically altered when chronically exposed to high blood glucose. AGEs damage the pericytes — support cells that wrap around capillary walls and regulate their calibre and integrity. As pericytes are lost, capillary walls weaken. They develop outpouchings called microaneurysms. They begin to leak plasma proteins, lipids, and eventually red blood cells into the surrounding retinal tissue.

Simultaneously, hyperglycaemia activates the polyol pathway and protein kinase C, generating oxidative stress that further injures endothelial cells. The capillaries become leaky, then occluded. Areas of retina downstream of occluded vessels become ischaemic — starved of oxygen. Ischaemic retina releases vascular endothelial growth factor (VEGF), a chemical signal that calls for new blood vessels to grow.

"Diabetic retinopathy is caused by prolonged hyperglycaemia, which damages the retinal microvasculature, leading to capillary leakage, ischaemia, and neovascularisation. Non-proliferative DR is characterised by microaneurysms, retinal haemorrhages, and may be associated with macular oedema. Proliferative DR involves the growth of new, fragile vessels on the retinal surface and into the vitreous."

— Indian Journal of Clinical and Experimental Ophthalmology · 2025 · doi:10.18231/j.ijceo.2025.001

These new vessels — the hallmark of proliferative diabetic retinopathy (PDR) — are biologically abnormal. They grow along the retinal surface and into the vitreous gel. They are fragile and bleed easily, causing vitreous haemorrhage. They contract, pulling on the retina and causing tractional retinal detachment. This is the end-stage of a process that began, silently, years or decades earlier with a few microaneurysms invisible to the patient.

⏱️

Duration is the most important risk factor

The AIIMS National Survey found that diabetes duration greater than 10 years had an odds ratio of 4.8 for diabetic retinopathy — the single strongest risk factor identified. Patients who have had diabetes for a decade or longer are nearly five times more likely to have DR than those with recent diagnosis. Poor glycaemic control (glucose ≥200 mg/dL) independently raised risk by 1.5×. Both are modifiable. Both are usually being addressed inadequately.

Layer 2 — Staging

Four stages. One window that closes silently.

Diabetic retinopathy follows a predictable progression. The tragedy is that the most treatable stages produce no symptoms — and the symptomatic stages are the ones where vision is already being lost.

1
Mild Non-Proliferative DR (NPDR)
Microaneurysms — tiny outpouchings in capillary walls — appear on the retina. These are the earliest visible sign of diabetic retinal damage. Vision is completely normal. No symptoms. Detectable only on dilated fundus examination or retinal photography. Treatment at this stage is glycaemic and blood pressure control — no ocular intervention needed yet.
No Symptoms · Treatable Early
2
Moderate to Severe NPDR
More extensive vascular damage — haemorrhages, hard exudates, cotton-wool spots (nerve fibre infarcts), venous beading. If the macula is involved (diabetic macular oedema, DME), central vision begins to blur. This is the critical intervention window: laser photocoagulation and anti-VEGF treatment are highly effective here. Without treatment, 50% of eyes with severe NPDR progress to PDR within one year.
DME may cause blur · Treat Now
3
Proliferative DR (PDR)
Neovascularisation — abnormal new vessel growth on the disc, retinal surface, or into the vitreous. These vessels bleed spontaneously, causing vitreous haemorrhage (sudden vision loss, floaters, dark shadows). Fibrovascular membranes contract, risking tractional retinal detachment. Pan-retinal photocoagulation (PRP) laser, anti-VEGF injections, and vitreoretinal surgery are the main treatments. Half of untreated severe PDR eyes become blind within 5 years.
Vitreous haemorrhage · Urgent
4
Advanced PDR — Tractional Retinal Detachment
Fibrovascular membranes pull the retina away from its supporting tissue. Central vision collapses. Vitrectomy — surgical removal of the vitreous and dissection of membranes — is the only treatment. Silicone oil tamponade holds the retina in place during healing. Visual outcomes depend critically on whether the macula has detached before surgery. If it has, significant permanent vision loss is likely even with technically successful surgery.
Retinal Detachment · Surgery Required
Layer 3 — The Gap

India knows. India does not act.

A study examining diabetic retinopathy awareness at a North Indian hospital produced findings that are both encouraging and devastating simultaneously. The encouraging part: 79% of diabetic patients knew that diabetes damages the eyes. 69.5% knew it could lead to blindness. The devastating part: 73.5% of those same patients had never had a dilated eye examination for DR screening. Only 17.6% had ever been referred to an ophthalmologist by their treating physician.

The Knowledge-Action Gap — Indian Diabetic Patients
Awareness is near-universal.
Action is catastrophically rare.
Aware that diabetes damages eyes79%
79% know the risk exists.
Aware DR can cause blindness69.5%
69.5% understand the stakes.
Have NEVER had a dilated eye exam73.5%
73.5% have never been screened despite knowing the risk. This is the gap that causes blindness.
Referred to ophthalmologist by their doctor17.6%
Only 17.6% were ever referred by their treating physician. The failure is systemic.
Source: PMC — Awareness of diabetic retinopathy among DM patients visiting a hospital in North India · PMC9067181 · 272 patients

This is not a knowledge problem. It is a system problem. Physicians managing diabetes — general practitioners, internists, endocrinologists — are not consistently making the ophthalmology referral that their diabetic patients require. Ophthalmologists are not embedded in diabetic care pathways. And patients, even when they know the risk abstractly, do not take action unless a clinician makes it urgent and specific.

The SMART India study (Lancet Global Health, 2022) confirmed this at population scale across ten Indian states: the national vision-threatening DR rate requires urgent screening and treatment infrastructure that currently does not exist. The study directly called for national policy to screen and treat VTDR — noting that without this, blindness rates will rise in direct proportion to the diabetes epidemic.

Layer 4 — The Resource Crisis

3 million patients. Fewer than 1,000 surgeons.

~3M
Indians with proliferative DR requiring specialist vitreoretinal care
Scientific Reports · 2020 · PDR incidence data
<1,000
Practicing vitreoretinal surgeons in India to treat them
Scientific Reports · 2020 · 1 surgeon per 3,000 PDR patients
97%
Sensitivity of Google/Aravind AI screening system across 600K+ patients in Tamil Nadu
JAMA Network Open · March 2025

India has approximately 3 million people with proliferative diabetic retinopathy — the advanced stage requiring vitreoretinal surgery. It has fewer than 1,000 practicing vitreoretinal surgeons. That ratio — one surgeon for every 3,000 patients — is not a gap. It is a canyon. Even if every existing vitreoretinal surgeon in India operated at full capacity, they cannot treat the existing backlog, let alone the new cases accumulating every year from the expanding diabetes epidemic.

This is why the AI screening breakthrough matters so much. Aravind Eye Hospitals partnered with Google and Verily to deploy an automated retinal disease assessment (ARDA) algorithm across Tamil Nadu. By March 2025, the system had screened more than 600,000 patients — achieving 97% sensitivity for severe DR. It referred patients with sight-threatening disease to clinic, creating a triage pipeline that does not require an ophthalmologist to make the initial screening decision.

The technology exists. The treatment protocols exist. The 98% preventability figure is real. What is missing is the policy infrastructure to make screening universal — and the products that enable treatment when disease is found.

🤖

AI screening changes the equation

The Google/Aravind ARDA algorithm had a 0% clinically important miss rate for severe or proliferative DR — every patient with vision-threatening disease was detected as at least moderate DR and referred to clinic. The system's negative predictive value was 99.9%. This is not experimental technology — it was deployed in real clinical practice across rural and urban Tamil Nadu, screening patients who would never otherwise have reached an ophthalmologist. The bottleneck is now treatment capacity and referral completion, not detection.

Layer 5 — Treatment

From laser to surgery — what actually works

Diabetic retinopathy has highly effective treatments at every stage. The tragedy is not that treatment doesn't exist — it is that patients reach treatment too late, or not at all.

Prevention · All Stages
Glycaemic & Blood Pressure Control
The DCCT and UKPDS trials proved that intensive blood glucose and BP control reduces DR incidence and progression by 50–75%. This is the only intervention that works before retinopathy begins — and continues to be effective at slowing progression at every stage.
Strongest Evidence
Screening · All Diabetics
Annual Dilated Fundus Examination
Every diabetic requires a dilated fundus examination at least annually, regardless of visual symptoms. Visual acuity testing is insufficient. Fundus photography or dilated ophthalmoscopy by a trained examiner is the standard. This is the intervention that converts the 98% preventability figure into reality.
Standard of Care
Moderate-Severe NPDR + PDR
Pan-Retinal Photocoagulation (PRP) Laser
Laser applied to the peripheral ischaemic retina destroys tissue that is producing VEGF, reducing the stimulus for neovascularisation. PRP is the proven, cost-effective treatment for high-risk PDR. Has reduced severe vision loss risk by 50% in landmark clinical trials. Portable laser systems now enable delivery in field settings.
Strong Evidence · 50yr track record
DME · NPDR · PDR
Anti-VEGF Intravitreal Injections
Ranibizumab, bevacizumab, and aflibercept block VEGF to reduce macular oedema and new vessel growth. Now first-line treatment for centre-involving DME. Highly effective but require repeated injections and specialist delivery — creating access challenges in low-resource settings.
Strong Evidence
Advanced PDR
Pars Plana Vitrectomy (PPV)
Surgical removal of vitreous and fibrovascular membranes causing tractional retinal detachment. Required when laser and anti-VEGF cannot manage the complication burden. Approximately one-third of PDR patients in India ultimately require vitreoretinal surgery — against fewer than 1,000 surgeons nationally.
Specialised — Limited Access
Post-Vitrectomy Tamponade
Silicone Oil Tamponade
After vitrectomy for complex retinal detachment, silicone oil holds the retina in anatomical position during healing. RETSIL 1000 (lower viscosity) and RETSIL 5000 (higher viscosity, for superior detachments) are Agaaz Ophthalmics' ophthalmic silicone oils for this indication.
Standard Surgical Step
Surgical Tool Spotlight — Vitreoretinal Tamponade

When the retina detaches, silicone oil holds the world together

In advanced proliferative diabetic retinopathy, fibrovascular membranes contract and pull the retina away from its supporting choroid. When this happens — tractional retinal detachment — vitrectomy is performed: the vitreous is removed, membranes are dissected, and the retina is reattached. To hold the retina in place while it heals, a tamponade agent is injected. For complex, inferior, or recurrent detachments, that agent is silicone oil.

Silicone oil — polydimethylsiloxane (PDMS) — is biocompatible, transparent, and provides the sustained mechanical support the healing retina requires. It is not absorbed by the body and is typically removed in a second procedure 3–6 months after confirmed retinal reattachment. The viscosity grade used depends on the anatomy: RETSIL 1000 (1,000 centistokes) for most cases; RETSIL 5000 (5,000 centistokes, denser) for superior and complex detachments where heavier oil improves tamponade.

Approximately 60% of PDR patients in India eventually require cataract surgery, and a third require vitreoretinal surgery. With 3 million PDR patients in the country, the demand for high-quality, GMP-certified silicone oil — reliably supplied, consistently pure — is both large and growing.

ProductRETSIL 1000
ProductRETSIL 5000
MaterialPDMS Silicone Oil
IndicationVitreoretinal Tamponade
For Every Diabetic

The only thing that prevents preventable blindness

The arithmetic is stark. Annual dilated fundus examination catches diabetic retinopathy in its treatable stages. At mild-to-moderate NPDR, treatment is straightforward and highly effective. At PDR, treatment is harder but still capable of preserving vision. Once tractional retinal detachment involves the macula, permanent central vision loss is likely even after surgical success.

The gap between "preventable" and "prevented" exists because of one failure: the annual eye exam is not happening. The reasons vary — lack of referral, lack of awareness that normal vision does not mean healthy eyes, cost and access barriers, distance to ophthalmology services. But the solution to all of these is the same: every person with diabetes, every year, regardless of whether their vision seems fine, needs a dilated eye examination.

📅

The standard of care in four sentences

Type 2 diabetes: Dilated eye exam at diagnosis (many patients have had undiagnosed diabetes for years before detection), then annually. Type 1 diabetes: Screening beginning 5 years after diagnosis, then annually. Known retinopathy: Every 3–6 months for moderate NPDR; every 1–3 months for severe NPDR or early PDR. Pregnancy with diabetes: Every trimester — pregnancy accelerates DR progression rapidly. In all cases: visual acuity testing alone is NOT sufficient. A dilated exam by a trained examiner is required.

Common Questions

Frequently asked questions

Diabetic retinopathy is a progressive microvascular complication of diabetes in which chronic high blood glucose damages the tiny blood vessels of the retina. These vessels leak, bleed, and eventually trigger the growth of abnormal new vessels that can cause vitreous haemorrhage and tractional retinal detachment. It is the leading cause of new blindness in working-age adults globally. The critical clinical point is that it produces no symptoms during its most treatable early stages — vision may be perfectly normal while significant retinal damage is accumulating.

India has approximately 77 million people with diabetes. The AIIMS National Survey (2015–19) found diabetic retinopathy in 16.9% of diabetics, with sight-threatening DR (STDR) in 3.6% — approximately 3–4.5 million people. The SMART India study (Lancet Global Health, 2022) confirmed these national estimates across ten Indian states. Of all STDR cases identified in the national survey, only 13.6% had been treated with laser photocoagulation — revealing a catastrophic treatment gap. India has fewer than 1,000 practicing vitreoretinal surgeons for an estimated 3 million PDR patients.

Up to 98% of blindness from diabetic retinopathy is preventable through timely screening, glycaemic control, laser photocoagulation, anti-VEGF treatment, and vitreoretinal surgery when needed. This figure is cited in Indian ophthalmology guidelines endorsed by the Ministry of Health. The tragedy is that despite this near-total preventability, the vast majority of sight-threatening cases in India remain undetected and untreated — primarily because annual dilated fundus examination is not happening consistently for the 77 million Indians who need it.

The peripheral retina is affected first by diabetic vascular damage, and peripheral vision loss goes unnoticed by most patients until it is severe. The macula — responsible for central, high-acuity vision — is affected later, either through diabetic macular oedema (gradual central blur) or through vitreous haemorrhage or tractional retinal detachment (sudden vision loss). By the time symptoms are noticeable to the patient, the window for simple laser treatment has often passed. This is why the annual dilated fundus examination exists — not to test vision, but to directly examine retinal tissue for damage before it becomes symptomatic.

Silicone oil (polydimethylsiloxane) is used as a tamponade agent in vitreoretinal surgery for advanced proliferative diabetic retinopathy. When fibrovascular membranes cause tractional retinal detachment, vitrectomy removes the vitreous and membranes, and silicone oil is injected to hold the retina in anatomical position while it heals. It is biocompatible, optically clear, and not absorbed by the body. It is removed in a second procedure once retinal reattachment is confirmed — typically 3–6 months post-operatively. RETSIL 1000 and RETSIL 5000 (differing viscosities) are manufactured by Agaaz Ophthalmics for this indication.

Every person with diabetes should have a comprehensive dilated fundus examination at least annually — regardless of whether vision seems normal. Indian guidelines recommend screening at diagnosis of Type 2 diabetes (many patients have had undiagnosed diabetes for years), then annually thereafter. Patients with known retinopathy require more frequent monitoring: every 3–6 months for moderate NPDR, every 1–3 months for severe NPDR or early PDR. Pregnant women with diabetes require screening every trimester. Visual acuity testing alone is NOT sufficient — a dilated examination of the fundus by a trained examiner is required.

References

Peer-Reviewed Sources

  • Williams HR. (2025). "Diabetic retinopathy: The rising tide." Indian Journal of Clinical and Experimental Ophthalmology, 11(1):1–3. doi:10.18231/j.ijceo.2025.001. [2025 India-specific editorial — biology and neovascularisation mechanism]
  • SMART India Study. (Lancet Global Health, October 2022). "Prevalence of diabetic retinopathy in India stratified by known and undiagnosed diabetes, urban–rural locations, and socioeconomic indices." PIIS2214-109X(22)00411-9. [77M diabetics, 125M projection, national VTDR data]
  • Vashist P et al. (Indian Journal of Ophthalmology, 2021). "Prevalence of diabetic retinopathy in India: National Survey 2015–19." PMC8725073. [16.9% DR prevalence, 3.6% STDR, 13.6% treatment coverage]
  • Indian Journal of Ophthalmology Guidelines. "Guidelines for the prevention and management of diabetic retinopathy in India." PMC7001190. [98% blindness preventability, STDR 3–4.5 million India estimate]
  • PMC. "Awareness of diabetic retinopathy among DM patients visiting a hospital of North India." PMC9067181. [73.5% never screened, 79% aware, 17.6% referred — 272 patients]
  • Scientific Reports. (2020). "Prevalence and incidence of visual impairment in patients with proliferative diabetic retinopathy in India." doi:10.1038/s41598-020-67350-6. [3 million PDR patients, <1,000 VR surgeons, 60% require cataract surgery]
  • Brant A et al. (JAMA Network Open, March 2025). "Performance of a Deep Learning Diabetic Retinopathy Algorithm in India." doi:10.1001/jamanetworkopen.2025.0984. [ARDA 600K+ patients screened, 97% sensitivity, 0% clinical miss rate for severe PDR]
  • PMC. "Situational analysis of diabetic retinopathy screening in India." PMC8725067. [3.35–4.55M VTDR at risk, 51% of global DR blindness from Asia-Pacific]
  • IAPB. "The emerging epidemic of diabetic retinopathy in India." iapb.org. [Almost half with diabetes had lost vision by time of diagnosis — 11 cities, 80+ eye hospitals]

When surgery is the
only option left,
the products must be right.

Agaaz Ophthalmics manufactures RETSIL 1000 and RETSIL 5000 ophthalmic silicone oils for vitreoretinal tamponade, alongside a complete cataract surgery ecosystem. GMP-certified. Exported to 15+ countries. Based in Ahmedabad, India.

Start writing here...