Glaucoma: Symptoms, Causes, Tests & Treatment

Overview

Glaucoma damages the optic nerve, the cable that carries visual signals from the eye to the brain. In most cases this happens because the fluid pressure inside the eye (intraocular pressure) rises and gradually injures the nerve fibres.

Glaucoma is often called the 'silent thief of sight' because the commonest form, primary open-angle glaucoma, causes no pain and no early symptoms. Vision is lost first from the sides (peripheral vision) and only noticed once significant damage has occurred.

Some patients have a narrower drainage angle in the eye and can develop acute angle-closure glaucoma, which causes sudden severe pain, redness and blurred vision and needs emergency treatment.

Symptoms

Chronic (open-angle) glaucoma usually has no early symptoms. When they do appear, they include:

• Gradual loss of side (peripheral) vision, often unnoticed until advanced
• Difficulty seeing in dim light or at night
• Frequent need to change spectacles without clear improvement
• In acute angle-closure glaucoma: sudden eye pain, redness, blurred vision, haloes around lights, headache, nausea and vomiting — this is an emergency

Causes

Glaucoma develops when the balance between fluid production and drainage inside the eye is disturbed:

• Reduced drainage of the aqueous fluid through the eye's natural drainage channels
• A narrow or blocked drainage angle (angle-closure glaucoma)
• Glaucoma secondary to eye injury, inflammation (uveitis), prolonged steroid use or advanced cataract
• Congenital glaucoma present from birth due to a developmental drainage defect

Risk Factors

• Age above 40 years
• Family history of glaucoma
• Diabetes and hypertension
• High myopia or high hypermetropia (predisposes to angle-closure)
• Long-term steroid use (drops, inhalers or tablets)
• Previous eye injury or eye surgery
• Thin cornea

When to See a Doctor

Book a routine glaucoma screening if you are over 40, have a family history of glaucoma, or have diabetes — even without any symptoms.

Seek emergency care immediately if you develop sudden severe eye pain with redness, blurred vision, haloes around lights, headache or vomiting — these suggest acute angle-closure glaucoma, which can cause permanent vision loss within hours if untreated.

Diagnosis

Glaucoma is diagnosed by combining eye pressure measurement, examination of the optic nerve, and functional testing of the visual field, since eye pressure alone does not confirm or rule out the condition.

Tests

• Applanation tonometry on the slit lamp to measure intraocular pressure accurately
• Slit lamp examination of the drainage angle and optic disc
• Dilated optic nerve evaluation to look for characteristic glaucomatous damage
• Perimetry (visual field test) on the Appasamy perimeter to map peripheral vision loss
• Anterior segment imaging to assess the drainage angle where indicated
• Optical coherence tomography (OCT) of the optic nerve fibre layer, available on a rental basis, for early detection and monitoring

Treatment Options

Glaucoma cannot be cured, but its progression can almost always be controlled if detected early. The goal of treatment is to lower eye pressure and protect the remaining optic nerve function.

• Eye pressure-lowering drops — usually the first line of treatment, often needed lifelong
• Laser procedures (such as laser peripheral iridotomy for angle-closure or SLT for open-angle glaucoma) to improve drainage
• Glaucoma surgery for cases not controlled with drops or laser
• Regular monitoring of eye pressure, optic disc and visual fields to track progression

Expected Outcomes

With regular use of prescribed drops and consistent follow-up, most patients with glaucoma retain useful vision for life. Vision already lost before diagnosis cannot be restored, which is why lifelong monitoring — even when vision feels normal — is essential.

Why Choose Dr. Murkute's O2 Bone & Eye Care

• Comprehensive glaucoma evaluation by Dr. Dipti Murkute (Pansare), MBBS, DNB Ophthalmology, FICO (UK)
• Accurate eye pressure measurement with the Appasamy 3-step slit lamp and applanation tonometer
• Visual field testing on the in-house Appasamy perimeter
• Access to OCT and anterior segment imaging for detailed optic nerve and angle assessment
• Structured long-term follow-up plans for lifelong glaucoma monitoring
• Convenient Kharadi location for patients across East Pune