Definition:

Glaucoma is a group of related eye diseases that damage the optic nerve of the eye. Optic nerve carries information from the eye to the brain and is vital for good vision. Its damage can result in vision loss or blindness.

Facts about Glaucoma

  • Second leading causes of blindness
  • Can occur at any age but is more common in older adults
  • Damage is often caused by an abnormally higher-than-normal eye pressure (ocular hypertension)
  • Generally show few or no warning signs or change in vision
  • Vision loss due to glaucoma can’t be recovered
  • Early detection and treatment can slow or prevent vision loss

Types of Glaucoma

Mainly glaucoma is of following two types:

  • Open-angle glaucoma or wide-angle glaucoma
  • Angle-closure glaucoma or acute or chronic angle-closure or narrow-angle glaucoma

Other than these, very rarely some people may have following types:

  • Low-tension or normal-tension glaucoma
  • Congenital glaucoma
  • Pigmentary glaucoma
  • Pseudo exfoliation glaucoma
  • Secondary glaucoma (complication of other medical conditions)

Risk factors of Glaucoma

Glaucoma does not show much of signs or symptoms before it reaches an advanced stage. That is why every individual should be well aware of the following factors that may raise their chance of developing glaucoma:

  • Age above 40 years
  • High internal eye pressure (intraocular pressure)
  • Black race
  • Family history
  • Poor vision
  • Eye injury or trauma
  • Previous eye surgery
  • Eye conditions like short-sightedness
  • Long term use of some eye medications especially corticosteroid
  • Certain medical conditions, such as diabetes, heart disease, high blood pressure etc.
  • Having certain eye conditions, such as short-sightedness
  • Early estrogen deficiency
  • Congenital (boys are affected more than girls)

Symptoms of Glaucoma

Most of the glaucoma patients show few or no symptoms in the initial stage of the disease. The very first sign appears as loss of peripheral vision of side vision that may go unnoticed till significant loss of vision occurs. Following symptoms should prompt an individual to get an eye check-up done to avoid any vision loss:

  • Sudden eye pain
  • Extreme headache
  • Blurred vision or vision loss
  • Narrowing of visual field.
  • Appearance of halos around lights
  • Eye redness
  • Hazy eyes
  • Cloudy, white, hazy, enlarged or protruding eye
  • Nausea or vomiting

Diagnosis of Glaucoma

An early detection of glaucoma plays most crucial role in the prevention of blindness due to glaucoma. So any individual who is at risk of developing glaucoma should regularly visit an eye clinic for comprehensive eye examination including the following:

  • Tonometry (measuring intraocular pressure [IOP])
  • Visual field test to determine if there is loss of side vision
  • Pachymetry to measure corneal thickness
  • Gonioscopy to inspect the ocular fluid drainage angle
  • Optical coherence tomography (OCT) to diagnosis the optic nervous tissue damage.

Glaucoma Treatment

As much as the early diagnosis of glaucoma is important, its early treatment is equally important. In fact if left untreated, it will eventually cause blindness.

Although the damage caused by glaucoma is irreversible, but still mediation can slow or prevent vision loss. Glaucoma treatment is aimed to lower pressure in the eye and may involve the following depending upon the patient condition and severity of disease:

  • Medication with eye drops like
    • Beta blockers
    • Prostaglandins
    • Alpha-adrenergic agonists
    • Carbonic anhydrase inhibitors
    • Miotic or cholinergic agents
  • Oral medication, usually a carbonic anhydrase inhibitor is prescribed in case eye drops fail to lower the IOP
  • Glaucoma filtering surgery called trabeculectomy
  • Laser surgery
    • Trabeculoplasty
    • Iridotomy
    • Cyclophotocoagulation
  • Insertion of drainage tubes
  • Electrocautery
  • Laser peripheral iridotomy

Glaucoma is a painless condition and patient generally become careless about strict use of eye drops. In fact the use of eye drops is uncomfortable or inconvenient that may also become a reason of treatment discontinuation. But this non-compliance with glaucoma medication is a major reason for blindness caused by glaucoma. So every patient should first consult the eye doctor about a possible alternative therapy before stopping any treatment by themselves.