Ocular Hypertension (High Eye Pressure): Causes, Symptoms & Treatment

What is high eye pressure?

High eye pressure, without any ocular damage, is known medically as ocular hypertension whereas high pressure with damage is a form of glaucoma. These occur when the intraocular pressure (IOP) is above the normal range, with the usual range being 10 - 21 mmHg (millimetres of mercury). Glaucoma is a progressive condition that can lead to severe vision loss.

What are the causes of high eye pressure?

Several factors can cause abnormally high IOP. The most common include:

• Overproduction of fluid: Your eye naturally produces a fluid called aqueous humour, and if too much is made, pressure builds up within your eye.

• Poor drainage: Aqueous humour is normally drained out through a mesh-like channel. If this system becomes blocked or isn’t working efficiently, pressure will rise.

• Overuse of steroids: Long-term use of medical steroids (such as eye drops, inhalers, or tablets) can increase eye pressure.

• Eye trauma: Past injuries, even if they occurred years ago, can lead to higher pressure within the eye.

• Genetics: Although high eye pressure is not directly hereditary, genetic factors can increase the likelihood of developing it.

What are the symptoms of high eye pressure?

In most cases, ocular hypertension and early glaucoma (high eye pressure) are asymptomatic, meaning there are no noticeable symptoms. This highlights the importance of routine eye examinations. However, in some cases of significantly elevated pressure, symptoms may include:

• Eye discomfort or pain
• Headaches
• Blurred vision
• Halos around lights
• Bloodshot eyes

What are the treatment options for high eye pressure?

There are multiple treatment options however, the approach taken depends on the severity of the pressure increase and whether there are other risk factors:

• Watch and wait: If the pressure is only slightly above normal and there are no other risk factors, healthcare professionals may suggest monitoring it with routine check-ups, with no immediate treatment required.
• Eye drops: Historically the most common treatment. Different types of eye drops lower eye pressure in different ways:

                           - Prostaglandin analogues: Help drain excess fluid from the eye.                           

                           - Beta-blockers: Reduce fluid production.

                           - Carbonic anhydrase inhibitors: Also reduce fluid production.

                           - Alpha agonists: Both reduce fluid production and improve drainage.

• Laser treatment: A quick and painless procedure where a laser is used to help the eye drain fluid more effectively.
• Surgery: If eye drops and laser treatments are not effective, surgery may be necessary. Surgical options include:

                           - Trabeculectomy: A procedure that creates a new drainage channel to help fluid flow out of the eye.

                           - Minimally Invasive Glaucoma Surgery (MIGS): A less invasive procedure designed to improve drainage.