Glaucoma is a disease that damages optic nerve of the eye. It usually occurs when the pressure inside the eye increases.

It is the leading cause of irreversible blindness worldwide, but blindness from glaucoma can often be prevented with early treatment.

Causes of Glaucoma?

Eye constantly produces a liquid called aqueous humor. As new aqueous flows into eye, the same amount should drain out. The fluid drains out through an area called drainage angle. If the drainage angle is not working properly, fluid starts accumulating inside the eye and pressure inside the eye raises. Raise in intraocular pressure leads to damage of optic nerve.

Types of Glaucoma:

There are two major types of glaucoma.

  1. Primary open angle glaucoma
  2. Primary angle closure glaucoma.

Open Angle Glaucoma: Most common type of glaucoma. In this pressure inside the eye raises due to clogging of the drainage angle.

  • There are no warning signs or obvious symptoms in the early stages.
  • As the disease progresses, patients peripheral vision will be affected.
  • Until the damage is quite severe, people do not notice any change in their vision. This is why glaucoma is called the “silent thief of sight”.
  • By regular eye checkups only glaucoma can be diagnosed in early stages before the vision is lost.

    Angle Closure Glaucoma:

  • It occurs when drainage angle of eye is blocked suddenly resulting in sudden rise of IOP.
  • Presents with sudden blurring of vision, severe eye pain, headache, nausea, vomiting, redness & rainbow colored rings (Colored Halos).

Risk Factors:

  • Age; ones 40 years but can occur in young people also
  • Family members with glaucoma
  • History of eye injury
  • High minus (-) power glasses (Myopia)
  • Long term use of steroids (Topical & systemic)
  • DM
  • Migraine
  • High BP
  • Poor blood circulation
  • Thin central corneal thickness

Diagnosis starts with Investigations:

  1. Tonometry (for measuring IOP):

Various NCT, Perkins tonometer, Pulse Air, Applanation tonometer

  1. Ultrasonic pachymeter: To know the central corneal thickness.
  2. Gonioscopy: To differentiate between open angle & angle closure glaucoma.
  3. Visual Fields: (HUMPHREYS Visual Field Analyzer)

To measure the extent of field of vision of patient.

  1. Slit Lamp Examination using 90D:

To examine the optic disc of the patient (optic nerve head)

  1. OCT (Optical Coherence Tonography): (CIRRUS-HD OCT)

To look for changes in optic nerve head & Retinal nerve fibre layer.

  1. Zeiss Fundus Camera:

To take stereoscopic picture of optic nerve head and retina.

Modes of Management:

  1. Medical Mx:

Glaucoma progression can usually be controlled with use of topical eye drops by reducing intraocular pressure.

  1. Laser Procedures:

Yag Peripheral Laser Iridotomy: Done in patients of angle closure glaucoma.

  1. Surgical Mx:


  • Done in patients with uncontrolled IOP with maximum topical eye drops
  • Poor compliance to medical management.
  • In trabeculectomy Sx, a new drainage channel is created for aqueous humour drainage so that IOP can be reduced.

Glaucoma Drainage Devices: Done in some cases like neovascular glaucoma, inflammatory glaucoma etc.