Different Types of Glaucoma

What is glaucoma?

Glaucoma is a progressive eye disorder. It occurs due to increased pressure of fluid inside the eyes due to excess fluid accumulation.

The fluid pressure damages optic nerves of the eye and causes vision impairment or gradually permanent loss of vision or blindness if left without treatment.

Glaucoma symptoms differ in different types of the disorder. Thus, proper diagnosis is necessary to check which type is causing these symptoms. The glaucoma is categorized based on following parameters-

  • Glaucoma is primary (occurs due to fluid pressure in eye – idiopathic) or Secondary (associated with other systemic or ocular conditions)
  • State of angle of anterior chamber of eye closure in glaucoma- open or closed
  • Severity- acute or chronic

Glaucoma symptoms

The most common type of glaucoma is primary open-angle glaucoma. It shows no signs or symptoms except vision loss over time. It’s important to get a periodic comprehensive eye exam so your eye specialist can monitor changes in your vision.

Symptoms of glaucoma are:

  • Eye pain
  • Nausea or vomiting
  • Colored rings around lights
  • Blurred vision
  • Vision disturbances
  • Redness in eyes

Types of glaucoma

Broadly, the various different types of glaucoma are:

  • Primary- occurs due to angle closure and fluid pressure increase inside the eye
  • Secondary- occurs due to other eye conditions, disorders and diseases

Open angle and angle closure are the most common forms of glaucoma found in 70-90% people. Other glaucomas are less common and are found in few people around the world.

Primary Glaucomas

These are ideally the glaucomas which occur due to state of angle of anterior chamber of the eye. Usually fluid pressure in eye damages optic nerves, which leads to these glaucomas. The different types of primary glaucomas are:

Primary Open Angle Glaucoma

It is the most common type of glaucoma. It is an eye disorder in which optic nerve is damaged mostly because of increased fluid pressure inside the eye. The fluid pressure pushes optic nerves causing damage to it.

Angle-closure glaucoma

It is the second most common type of glaucoma found in people. It is one of the largely inherited disorder. It occurs suddenly and cause symptoms such as

  • Eye pain
  • Headache
  • Nausea and vomiting
  • Halos seen around lights in rare cases

This glaucoma occur when fluid from the eye suddenly stops draining due to obstruction of drainage angle of the eye.

Angle closure glaucoma is further classified into two categories:

Acute angle closure glaucoma: It begins suddenly when intraocular pressure of eye increases due to blockage of drainage canal.

Chronic angle closure glaucoma: This happens when the angle or mouth of the drainage canal covers slowly and results in increased intraocular pressure and optic nerve damage.

Childhood glaucoma

It is a rare form of glaucoma often associated with increased eye pressure. This types of glaucoma exists at birth or develop later in an individual. The following symptoms are seen in a child with this glaucoma-

  • Enlarged and cloudy eyes
  • Excessive fluid coming out from eyes
  • Sensitivity of eyes towards light

Childhood glaucoma is further classified into three categories:

  • Congenital
  • Infantile
  • Juvenile

Secondary glaucoma

This type of glaucoma occurs as a result of other eye diseases and conditions such as eye injury, previous history of eye operation or injury, trauma, inflammation in eyes, tumour, advanced cataract and prolonged use of some drugs like corticosteroids which increase eye pressure that lead to damage of optic nerve and vision loss.

The secondary glaucoma can be open or closed angle and the damage to drainage canal is treated with the help of surgery.