Glaucoma refers to a group of eye conditions that cause damage to the optic nerve causing gradual loss of vison.

Affecting peripheral vision first, glaucoma is colloquially referred to as thief of sight.

Dr Ridia Lim is an authority on the management and treatment of glaucoma.

What is Glaucoma?

Glaucoma is the name given to a group of eye conditions resulting in loss of vision due to damage to the nerve at the back of the eye (the optic nerve).

Most commonly this visual loss is gradual, and starts in the peripheral vision, so is often not noticed by the patient until visual loss is severe and involving the central vision.

Often this occurs in conjunction with elevated pressure in the eye (intraocular pressure or IOP).

Types of Glaucoma

There are a number of types of glaucoma, and each will lead to different treatment pathways in discussion with your ophthalmologist.

These are listed below.

Open Angle Glaucoma (OAG)
Where the drain of the eye is wide open

Closed Angle Glaucoma (CAG)
Where the drainage system of the eye is partially or fully blocked, obstructed.

Primary Glaucoma
Where there are no apparent causes to the disease.

Types of Primary Glaucoma are:

  • Primary Open Angle Glaucoma (POAG)
  • Acute Angle-Closure Glaucoma (AACG)
  • Primary Angle-Closure (PAC)
  • Primary Angle-Closure Glaucoma (PACG)
  • Normal Tension Glaucoma (NTG)
  • Juvenile Glaucoma (Open or Closed) (JOAG or JCAG)

Secondary Glaucoma
Where another condition, injury or problem causes the glaucoma to develop.

Types of Secondary Glaucoma are;

  • Pigment Dispersion Syndrome
  • Pseudo-Exfoliation Syndrome
  • Neovascular (Rubeotic) Glaucoma
  • Traumatic Glaucoma
  • Iridocorneal Endothelial Syndrome (ICE)
  • Steroid-Induced Glaucoma
  • Uveitic Glaucoma
  • Mixed Mechanism Glaucoma

Causes of Glaucoma

There are many potential underlying causes for glaucoma and a thorough history, examination and some additional tests are required to determine the cause in each case.

Glaucoma is typically caused by high pressure at the front of the eye which damages the optic nerve at the back of the eye.

Underlying causes for glaucoma can be related to:

  • Abnormalities affecting only the eye
  • Systemic conditions such as diabetes
  • Use of some medications such as steroid medications
  • Prior trauma to the eye can also cause glaucoma

Risk factors to consider for glaucoma include:

  • Family History of Glaucoma
  • High Intraocular Pressure
  • Age (More prevalent in those aged 50 & over)
  • African or Asian Descent
  • Diabetes
  • Long or Short-Sighted
  • Steroid Use
  • Migraines
  • Eye Injury
  • Previous Eye Operation
  • High or Low Blood Pressure
  • Sleep Apnoea

Symptoms of glaucoma
As glaucoma is a slow progressive disease, it usually presents with no symptoms before it is quite progressed. Symptoms when experiences start with loss of peripheral or side vision.

What is a glaucoma suspect?
Doctors may deem a patient “glaucoma suspect” if they believe the patient is showing early signs of glaucoma however there is yet to be concrete evidence to make a definitive diagnosis. Ongoing monitoring and care will allow a diagnosis to be made and treatment made available to prevent the progression of the disease.

Treating Glaucoma

The purpose of any glaucoma treatment is to relieve or reduce the intraocular eye pressure IOP from the back of the optic nerve to reduce risk of damage.

Damage to the optic nerve causes vision loss.

Although there is currently no cure for glaucoma, the condition can be successfully managed with either one or a combination of:

  • medication (eye drops or tablets)
  • laser treatment
  • surgical treatment

Any vision lost to glaucoma cannot be restored. However, glaucoma treatment aims to maintain and preserve what you have and hopefully prevent further loss, so the earlier glaucoma is detected the better.

In newly diagnosed glaucoma or ocular hypertension, patients and their ophthalmologist will need to decide to start treatment with either medication or laser as a first step.

Prior to the LiGHT study both treatments were considered equally acceptable and appropriate as a first line of treatment, though commencement of medication first was a more common practice. The LiGHT study proved that laser treatment was an equally acceptable first line of treatment.

Treatment Options

Medication therapy

Types of medication used to treat glaucoma include:

  • Oral: Oral medication may be used as a short-term treatment to reduce IOP
  • Eye Drops: The most common form of treatment aims to reduce IOP

Laser Therapy

There are a number of different laser options available for glaucoma. The best option for each patient will depend on many factors, including the type of glaucoma, severity, and other medical problems.

Types of laser treatment in glaucoma to help to lower intraocular pressure in the eye:

Selective Laser Trabeculoplasty (SLT)

This is a laser procedure that helps the fluid in the eye drain better through a specific area called the trabecular meshwork.

The procedure can be done in the clinic, and the patient will only need some numbing drops for their eyes.

It’s often done in two separate sessions, with about a week between them to reduce eye inflammation.

After the treatment, the pressure inside the eye often decreases enough so the patient can stop using some of the eye pressure-lowering medications.

For those that prefer not to use eye drops or if this method suits your type of glaucoma, it can be used as the first treatment option.

Laser Peripheral Iridoplasty (LPI)

This treatment involves making a very small hole in the coloured part of your eye, called the iris.

The purpose is to prevent fluid from getting trapped behind the iris, which could lead to a harmful eye pressure.

The procedure is done in clinic, and the patient will receive numbing drops for comfort.

Afterward, the patient may need to use eye drops for about a week to reduce inflammation.

This treatment is recommended for patients whose eye structure puts them at risk of having a condition called angle closure.

Cyclodiode Laser (CPC)

This laser procedure helps reduce the amount of fluid your eye produces, which, in turn, lowers the eye pressure.

It can be done in a procedure room at the clinic or in a theatre.

The patient will receive aesthetic eye drops for comfort. It usually takes about 4 weeks to see the full effect of the treatment, so the patient is advised keep using any glaucoma medications you’ve been prescribed during this period.

Surgical Therapy

There are a number of different surgical options available for glaucoma. The best option for each patient will depend on many factors, including the type of glaucoma, severity, and other medical problems.

Types of surgery used to treat glaucoma include:

Minimally invasive glaucoma surgery (MIGS)

There are several types of surgical procedures known as ‘minimally invasive glaucoma surgery’ or MIGS. These procedures involve inserting small stents during cataract surgery to treat both cataracts and glaucoma.

MIGS is performed together with cataract surgery. A tiny stent is placed in the drainage area of your eye before removing the cataract. It adds about 10 extra minutes to the standard cataract procedure, but it doesn’t increase the risk of complications. The procedure is usually done with local anaesthesia and sedation. Vision improves rapidly, usually within 1 to 3 days.

Afterward, you’ll have the same follow-up appointments as a regular cataract patient however patients will still need lifelong monitoring for glaucoma.

Glaucoma Drainage Devices (GDD)

Glaucoma drainage devices are special tools used in the treatment of glaucoma, a condition that affects the pressure inside the eyes.

These devices help to lower the eye pressure by creating a tiny pathway for excess fluid to drain out of the eye.

By doing so, they prevent the pressure from building up and causing damage to the optic nerve, which is essential for clear vision.

The placement of these devices is done in clinic and with local anaesthesia and sedation.

Glaucoma drainage devices can be very effective in managing glaucoma and preventing further vision loss, especially in cases where other treatments may not be sufficient.


This is a traditional glaucoma procedure where a small cut in the white part of your eye (sclera) is made to create a new pathway for fluid to drain out. It helps to reduce the pressure inside your eye when other treatments haven’t worked well enough.

The procedure takes about 30 minutes to complete in clinic and is done with local anaesthesia and sedation.

After the surgery, there will be stitches in your eye, which will be taken out after 1-2 weeks depending on how well you heal.

You’ll have a check-up at the clinic the day after the surgery, and then weekly for 2 weeks. To prevent infection, you’ll need to use antibiotic eye drops for at least 1 week after the operation, and anti-inflammatory eye drops for 12 weeks. You may be able to stop using your glaucoma medications, but this will be decided by your doctor.

Educational Videos

Please see at the links below a number of education videos on glaucoma and its treatment.

If you have any questions about this condition and its treatment you may be able to find the answers at out FAQ’s page, or alternatively please don’t hesitate to ask a friendly staff member on your visit.

Treatment Options for Patients Diagnosed with Glaucoma

Hosted by Glaucoma Australia’s CEO Annie Gibbins watch Hunter Street Eye Specialists’ Ophthalmic Surgeon & Head of Glaucoma Unit at Sydney Eye Hospital Dr Ridia Lim together with her fellow Dr Kalliopi Giannopoulous discuss treatment options for those diagnosed and living with Glaucoma.

iStent: A Treatment Option for Patients Diagnosed with Glaucoma

iStent inject® W is indicated for use in adult patients with mild-to-moderate open-angle glaucoma that are undergoing cataract surgery.

More Information