What Is Ocular hypertension (Pressure in eye)?
Ocular hypertension occurs when there is raised intra-ocular pressure (increased pressure in the eye). It is important to diagnose and treat ocular hypertension promptly, as it can progress to irreversible vision loss and glaucoma.
Ocular hypertension occurs when there is a problem with drainage of aqueous fluid from the anterior aspect of the eye. The ciliary bodies that surround the eye’s lens continually produce aqueous fluid. This fluid drains from the eye via a trabecular meshwork, and then enters the body's bloodstream. The balance between production and outflow of aqueous humour is critical in maintaining normal eye pressures. Vitreous humour present in the posterior chamber of the eye has a constant volume and does not have an effect on eye pressure.
Ocular hypertension is caused when there is an abnormality with production or outflow of aqueous fluid. The normal pressure of the eye is between 12 to 21 millimetres of mercury (mmHg). Ocular hypertension is an increase in ocular pressure with no evidence of concurrent visual loss or optic nerve damage.
Ocular hypertension may be present without any symptoms, so regular examination of eye pressures by an optometrist or ophthalmologist is recommended. Tonometry is the investigation performed to assess the eye’s pressure. Two readings above 21mmHg are sufficient to diagnose ocular hypertension.
People who have ocular hypertension are referred to as "suspects of glaucoma." Monitoring and management of pressures are needed to prevent optic nerve damage.
What Are The Symptoms Of Ocular hypertension (Pressure in eye)?
Ocular hypertension is usually asymptomatic until consequences such as ocular nerve injury or vision loss occur. Symptoms that may suggest raised intra-ocular pressure include peripheral vision loss, painful or red eyes.
What Are The Causes Of Ocular hypertension (Pressure in eye)?
Ocular hypertension is caused when there is an imbalance between aqueous humour production and outflow. Many associated risk factors predispose to development of raised intraocular pressure. These include:
- Medications that increase intra-ocular pressure. Corticosteroids (systemic and topical) are the biggest culprits.
- Problems with aqueous humour outflow due to angle closure or damage to the trabecular meshwork in the anterior eye chamber.
- Inflammation of structures in the anterior and middle parts of the eye-Iritis or uveitis (infection of the iris or uvea).
- Congenital abnormalities of sight such as axial myopia (primary congenital glaucoma).
- Nearsightedness (myopia)
- The family history of glaucoma or ocular hypertension.
- Old age (increase in frequency seen over 40 years).
- Eye trauma
- Eye surgery may predispose to raised IOP. Cataract surgery is often implicated.
- Ethnicity- increased incidence in African descendants.
- Diabetes may predispose to raised IOP.
What Are The Things One Should Do To Manage Ocular hypertension (Pressure in eye)?
- Cardiovascular exercise has shown to reduce IOP transiently
- Stress reduction methods like meditation and breathing exercises can help lower IOP.
- Relaxation exercises for eyes can be done. These include blinking the eyes every 3-4 seconds, especially when staring at screens like laptops, tablets or television for extended periods. Blinking reduces pressure in the eyes and helps it to relax.
- Strengthen your eye muscles: Draw an imaginary figure eight in the air and follow it with your eyes. Practice focusing on near and far objects e.g. hold your hand in front of your nose and alternately focus on your finger and a distant object.
What Are The Things One Should Avoid To Manage Ocular hypertension (Pressure in eye)?
- Yoga has shown to increase IOP transiently. Avoid positions where the head is lower than the heart.
- Playing wind instruments such as clarinet, oboe, and trumpet also has transient increase pressure effects in the eye.
What Are The Best Foods For Ocular hypertension (Pressure in eye)?
1. Antioxidants have been shown to reduce IOP and to prevent glaucoma. Foods that contain vitamins C, A and E are indicated:
- Vitamin C rich foods: Grapefruits, strawberries, oranges, papaya
- Vitamin A: Kale, Spinach, butter, eggs, carrots
- Vitamin E: Almonds, kale, butternut, sweet potato
2. Omega 3 containing foods: Salmon, tuna, almonds, shellfish. Omega 3 reduces inflammation and assists nerve health.
3. Lutein and zeaxanthin reduce damage to the optic nerves. They are known as carotenoids that have anti-oxidant properties. They can be found in egg yolks, spinach, kale, broccoli
4. Alpha-lipoic acid (ALA) provides an antioxidant effect. Potatoes, spinach, liver, and yeasts are good sources
5. Grapeseed extract improves eyesight by reducing stress on eyesight.
What Are The Worst Foods For Ocular hypertension (Pressure in eye)?
- Caffeine. Caffeine increases systemic and ocular pressure.
- Avoid consuming large amounts of fluids at one time as this may increase IOP. Smaller, more frequent intake of fluids is indicated.
- Foods high in saturated fatty acids- these cause imbalance in the body’s lipid balance, and lowers omega 3, which has beneficial effects on sight.
What Are The Medicines For Ocular hypertension (Pressure in eye)?
The medical treatment of ocular hypertension is similar to wide angle glaucoma. Reduction of IOP is necessary to prevent the development of glaucoma and other vision loss.
Topical eye drops are the mainstay of treatment. These include prostaglandin agonists that increase the uveal outflow of aqueous humour. Latanoprost is often used. Beta-blockers reduce the amount of humour production by the ciliary bodies. Timolol is a common beta-blocker used.
Carbonic anhydrase inhibitors reduce ciliary humour production (the effect is less than with beta-blockers).These include brinzolamide, acetazolamide. Alpha agonists reduce production of aqueous humour as well as increasing use scleral outflow. Brimonidine is usually the first line of alpha agonists used.
Often combinations of the above classes are used to increase patient compliance and efficacy of treatment.
If reduction of pressure is not possible with medications, a diagnosis of wide angle glaucoma should be considered.
Surgery or laser treatments are usually not used in ocular hypertension.
What Are The Tips To Manage Ocular hypertension (Pressure in eye)?