Glaucoma: Why It Happens and How to Treat It

What Is Glaucoma?

Glaucoma is a slowly progressive, insidious eye disease that usually is associated with a progressive rise of intraocular pressure (IOP). In second to cataracts, it is the most common cause of blindness worldwide, affecting 7.7 million people. 

What is the Main Cause of Glaucoma?

The exact reason for what causes glaucoma is still a big mystery among researchers. However, the mechanism of how it develops is believed to be due to fluid within the eye, called aqueous humor, which would typically have a continuous drainage system. 

As we age, these drainage canals would decrease in outflow, inhibiting aqueous flow. Simultaneously, the aqueous humor production would still be the same, creating an imbalance between production and outflow. The imbalance contributes to rising pressure levels in the eyes due to fluid accumulation. 

Prolonged elevation of eye pressure (or intraocular pressure) causes nerve fibers in the optic nerve to die out, leading to vision loss. 

Also read – Glaucoma and Eye Pressure 

What Are the Types of Glaucoma? 

Glaucoma is a group of eye diseases with different underlying mechanisms as to how it develops. Here are some examples: 

• Open-angle - this type is the most common, affecting up to 90% of Americans who have glaucoma. It is caused by the presence of numerous tiny deposits, causing build-up and putting pressure on the optic nerve. 

• Closed-angle - It occurs when the angle between the iris and cornea is too narrow, blocking the drainage canals for fluid to leave the eye. As a result, it causes an acute elevation in eye pressure.

• Normal-tension glaucoma - Optic nerve damage that occurs even when eye pressure is normal for reasons unknown. This type of glaucoma is more common among Asians.

• Congenital - Congenital forms of glaucoma are due to incomplete development of drainage canals in the eyes of some babies.

Who Is At Risk? 

In general, anyone can get glaucoma. However, the following parameters can increase your risk of having glaucoma:

• Diabetes
• Family history of glaucoma
• Increasing age
• African American and Latinos 
• Farsightedness or hyperopia (for closed-angle glaucoma).
• High blood pressure (hypertension).
• Long-term use of corticosteroids.
• Nearsightedness or myopia (for open-angle glaucoma).
• Previous eye injury or surgery.

Diabetes and Glaucoma? How Does It Connect? 

Having diabetes  imposes a risk of developing glaucoma. In fact, people with diabetes are twice as likely to develop glaucoma as are non-diabetics. 

Neovascular glaucoma is a rare type of glaucoma that occurs in patients with diabetes. In some cases, diabetic retinopathy leads to the formation of new blood vessels on the retina that are abnormal and dangerous.

If these new blood vessels grow on the iris, it closes off the fluid flow in the eye and raises the eye pressure. 

What Are the Signs and Symptoms of Glaucoma? 

Signs and symptoms of glaucoma often appear later in the disease's gradual progression. Because of this, only half of glaucoma patients are aware of their condition. However, early identification and treatment are essential to stop the course of glaucoma since damage to the optic nerve is irreversible.

The signs and symptoms of glaucoma vary depending on the type and stage of your condition. 

For example:

Open-angle glaucoma

• Spotty blind spots that appear often in both eyes, either on the periphery (side vision) or in the center
• Tunnel vision in the advanced stages

Acute angle-closure glaucoma

• Severe headache
• Eye pain
• Nausea and vomiting
• Blurred vision
• Halos around lights
• Eye redness

How Is Glaucoma Diagnosed?

Regular eye examinations allow for the early detection of glaucoma and the correct preventative actions to stop its development. Exams of the eyes may measure the loss of vision and optic health.

A comprehensive eye exam includes:

• Visual acuity test - to test whether you can see well. . Your doctor will ask you to read close-up and distant letters.
• Visual field test - to test side vision (peripheral vision). How well you can perceive items out of the corner of your eye without shifting your gaze is the focus of this exam.
• Eye muscle function test - in order to look for issues with your eye muscles.
• Pupil response test - by flashing a tiny flashlight into your eyes and seeing how the pupils respond to the light, you may determine how light enters your eyes.
• Tonometry test - to determine your eyes' pressure. Your eye will either be softly touched with a particular tool or quickly blasted with air by a machine.
• Dilation - to check for problems with the inner parts of your eye. You'll be given eye drops by your doctor to dilate (widen) your pupil. This enables the physician to see into your eye.

How Often Should You Get an Eye Exam?

Your risk for eye illness will determine how frequently you require a dilated eye test. Consult your doctor to determine what is best for you.

It is recommended to get an eye exam every 1 to 2 years if: 

• age 60 or older
• Are African American, older than 40, and 
• have a glaucoma family history

The frequency of your exams should be discussed with your doctor if you have diabetes or high blood pressure. Most diabetics and persons with high blood pressure should have an eye checkup at least once per year.

What Is the Management of Glaucoma? 

It’s essential to start treatment right away. There is no treatment for glaucoma, and it won’t undo any damage to your vision, but it can stop it from getting worse. 

The goal of management for glaucoma is to decrease intraocular pressure in the eye. Depending on the severity, this would dictate how management will start. Eye drops are usually the mainstay for treating glaucoma. 

Here are the treatment options for glaucoma: 

• Eye Drops - these are the first line of treatment for glaucoma. Several different types, commonly nonspecific beta-blocker or prostaglandin analog, drops, all work by reducing the pressure in your eyes.
• Oral Medications - used alongside eye drops if the initial prescription of eye drops does not decrease eye pressure. These oral medications include carbonic anhydrase inhibitors. 
• Surgery - Surgery is indicated if eye drops and oral medications fail to relieve increasing eye pressure. For these scenarios, the goal is to improve fluid drainage within the eye to relieve eye pressure. 

Also read - Minimally Invasive Glaucoma Surgery 

Is Glaucoma Very Serious? 

Glaucoma can lead to further damage to the optic nerve when left untreated. A damaged optic nerve decreases the ability to transmit information from the eyes to the brain, eventually leading to vision loss and blindness. 

Once damage to the optic nerve is present, no treatment can reverse it back to its normal state. That is why early detection and prevention increases your chance of delayed glaucoma progression.

Early Detection is Early Prevention 

The most effective way to prevent glaucoma is to schedule annual eye exams. Our team of eye care professionals at Texas Eye and Cataract offers a multitude of services, aimed at the early detection of impending glaucoma development. We provide eye exams, medications, and surgical procedures to slow or reduce vision loss.