Ocular Surface Disease refers to a group of conditions that affect the surface of the eye, including the cornea, conjunctiva, and tear film. It commonly causes symptoms like dryness, irritation, redness, and discomfort, and can impact vision if not properly managed.

Close your eyes. Open them. In the half-second that takes, a film of tears has just spread across the front of your eye, smoothing optical irregularities and delivering oxygen and antimicrobial protein to the surface. When the system works, you never think about it. When it stops working, it is the only thing you think about.
Ocular surface disease (OSD) is the umbrella term for conditions affecting the conjunctiva, cornea, tear film, and the glands that support them. The ocular surface is the front face of the eye: the transparent cornea, the conjunctiva lining the whites and inner eyelids, and the tear film that keeps the whole surface lubricated, nourished, and optically clear. When any of these components fails, the result is discomfort, blurred vision, and, in severe cases, permanent corneal scarring and vision loss.
The spectrum is wide. Dry eye disease is the commonest face of OSD, but the category also includes meibomian gland dysfunction, blepharitis, allergic and infective conjunctivitis, pterygium, pinguecula, chemical and thermal injuries, Stevens-Johnson syndrome, ocular cicatricial pemphigoid, and limbal stem cell deficiency. Treatment scales accordingly, from simple lubrication and lid hygiene at one end to advanced surgical reconstruction at the other.
Vasan Eye Care runs a dedicated ocular surface clinic led by cornea and external disease specialists, covering the full range of presentations with evidence-based medical and surgical care.
OSD is remarkably prevalent in India, and it is also remarkably undertreated. The combination of hot and dry climate across many regions, high levels of air pollution in cities, widespread and prolonged digital device use, and limited access to early eye care has produced a perfect storm. Dry eye disease alone is estimated to affect anywhere from 18 to 54 percent of Indians across various population studies, with digital eye strain and environmental exposure doing most of the damage.
Allergic conjunctivitis is endemic, and it is closely tied to keratoconus through the mechanism of eye rubbing. Chronic rubbing, provoked by itch, is one of the strongest modifiable risk factors for keratoconus progression. Treating the allergy is not just about comfort; it protects the cornea from mechanical damage.
Chemical injuries from lime (calcium hydroxide) used in construction, pan (betel) preparation, and agricultural settings represent a specific and severe ocular emergency in India. Alkali burns are more dangerous than acid burns because alkali penetrates deeper into the eye, and they need immediate, copious irrigation before any further examination. Pterygium, the fleshy encroachment of conjunctiva onto the cornea, is common in rural and outdoor-working populations exposed to UV and dust. Vasan Eye Care’s ocular surface service sees the full range.
| Condition | Primary Feature | Main Treatment Approach |
|---|---|---|
| Dry Eye Disease | Tear film instability; surface desiccation | Lubricants, lifestyle, anti-inflammatory drops, punctal plugs |
| Meibomian Gland Dysfunction (MGD) | Blocked oil glands; evaporative dry eye | Warm compresses, lid massage, intense pulsed light (IPL) |
| Blepharitis | Eyelid margin inflammation; bacterial or demodex | Lid hygiene, antibiotics, tea tree oil for demodex |
| Allergic Conjunctivitis | IgE-mediated; seasonal or perennial | Antihistamine drops, mast cell stabilisers, cold compresses |
| Vernal Keratoconjunctivitis (VKC) | Severe allergic inflammation; shield ulcers | Cyclosporine, steroids, supratarsal steroid injection |
| Pterygium | Conjunctival growth onto the cornea | Surgical excision with conjunctival autograft |
| Chemical Injury | Alkali or acid damage; limbal stem cell loss | Emergency irrigation, amniotic membrane, SLET / CLET |
| Limbal Stem Cell Deficiency (LSCD) | Failure of corneal surface renewal; vascularisation | SLET, CLET |
| Stevens-Johnson Syndrome (SJS) | Severe mucocutaneous reaction; conjunctival scarring | Acute: amniotic membrane; chronic: scleral lenses, mucous membrane grafts |
Diagnosis starts with a careful history. What do the symptoms feel like? Grittiness, burning, redness, watering, photophobia, or blurred vision that clears with a blink? How long? What medications does the patient use? Is there a systemic disease or an occupational or environmental exposure that matters? The story often tells you what category of OSD you are dealing with before a single test is done.
Slit-lamp examination of the eyelid margins, conjunctiva, cornea, and tear film is the cornerstone of the workup. Specific tests add objectivity:
| Treatment | Approximate Cost Range (INR) |
|---|---|
| OSD evaluation (TBUT, staining, meibography) | 1,500 to 5,000 |
| Punctal plug insertion (per punctum) | 2,000 to 6,000 |
| Pterygium excision with conjunctival autograft | 20,000 to 50,000 |
| Amniotic membrane transplantation | 15,000 to 40,000 |
| SLET (limbal stem cell transplantation) | 50,000 to 1,20,000 |
| Scleral contact lens fitting | 15,000 to 40,000 |
Costs vary by severity and procedure. Vasan Eye Care works out a personalised plan after initial assessment.
Response depends entirely on the underlying condition. Mild to moderate dry eye usually improves substantially with lubricating drops, lid hygiene, and fixing environmental triggers. More advanced disease may need months of anti-inflammatory therapy before the improvement feels real and sustained. After pterygium excision, expect two to three weeks of redness and mild discomfort; the conjunctival graft integrates over six to eight weeks.
For severe disease such as SJS or chemical injury with limbal stem cell deficiency, the timeline is measured in months, not weeks. The realistic goal is to stabilise the surface and maximise remaining vision, not to restore things to perfectly normal. Saying that honestly is part of looking after these patients well.
Dry eye is the most common form of OSD, but OSD is a broader category that includes all conditions affecting the conjunctiva, cornea, tear film, and eyelid margins: allergic conjunctivitis, pterygium, chemical injuries, limbal stem cell deficiency, and more. Saying “I have dry eye” often understates what is actually going on.
Counterintuitive, but classic. Dry eye triggers reflex tearing: the surface irritation provokes the lacrimal gland to dump a surge of watery tears. These reflex tears lack the mucin and lipid layers that hold a normal tear film together, so they drain off quickly and the dryness remains. Watering that comes with grittiness is usually a sign of dry eye, not of a tear duct blockage.
The meibomian glands run along the eyelid margins and produce the oily outer layer of the tear film, which stops the underlying watery layer from evaporating. When the glands block or stop working, the tear film evaporates too fast. This is evaporative dry eye, and it is the commonest form. Treatment is warm compresses to soften the waxy secretions, lid massage to express them, and in more stubborn cases intense pulsed light (IPL) therapy or thermal pulsation devices.
Yes. A growing pterygium distorts the cornea and induces astigmatism, which blurs vision. If it creeps across the visual axis, it obstructs vision directly. The sensible time to remove a pterygium is before either of those things happens, not after. Watching it grow across the pupil and then operating is treating a problem you could have prevented.
The limbus is the ring where cornea meets conjunctiva, and it is where the stem cells that renew the corneal surface live. Destroy those stem cells (chemical burns, radiation, chronic contact lens overwear, severe inflammation) and the cornea cannot renew itself. Conjunctiva grows over the cornea, blood vessels invade, and vision suffers. SLET (simple limbal epithelial transplantation) or CLET procedures bring stem cells from the other eye or a donor to reseed the surface. It is delicate, elegant work.
Yes, especially for anyone using drops frequently. Preservatives in multi-dose bottles (benzalkonium chloride is the worst offender) themselves damage the ocular surface with repeated use. If you are using drops more than four times a day, switch to preservative-free single-dose vials. This is one of those changes that seems trivial and genuinely is not.
Yes. Contact lens wear reduces corneal sensitivity over time, alters the tear film, and creates a low-grade inflammatory state even when everything looks fine. It is also a route for infection. Patients with lens-related OSD often benefit from switching to daily disposables, reducing wearing hours, or in selected cases moving to scleral lenses under specialist supervision.
VKC is a severe form of allergic conjunctivitis, most commonly seen in young boys in tropical and subtropical regions, India very much included. Intense itching, thick mucous discharge, cobblestone papillae on the inner upper eyelid, and sometimes shield ulcers on the cornea. Shield ulcers are a genuine problem because they threaten vision. VKC needs active management with topical immunosuppressants, not just antihistamines.
In the acute phase, amniotic membrane transplantation laid over the ocular surface within the first few days can dramatically reduce the scarring that otherwise follows. In the chronic phase, scleral contact lenses and mucous membrane grafts manage the long-term consequences: lid adhesions, severe dry eye, recurrent surface breakdown. Acute SJS needs aggressive eye care from day one. A neglected surface in that window becomes permanent damage.
Yes. The cornea and external disease specialists manage the full spectrum, from simple dry eye and blepharitis to pterygium surgery, amniotic membrane transplantation, and limbal stem cell transplantation.
References
* DEWS II Report. Tear Film and Ocular Surface Society, 2017.
* American Academy of Ophthalmology. Dry Eye Syndrome.
* PMC / NCBI. Ocular Surface Disease: A Review, 2020.