Glaucoma

Glaucoma is a condition in which the pressure increases within the eye (intraocular pressure). If left untreated, it leads to irreversible visual field loss, tunnel vision and eventually, blindness. The most common type of glaucoma is open-angle glaucoma, which often exhibits no symptoms besides a gradual loss of vision. Angle-closure glaucoma, on the other hand, is characterised by a sudden visual disturbance with eye pain and nausea. Although rare, it is a medical emergency and should be addressed immediately.

Most patients can be treated with drops that lower the pressure of the eyes. If this treatment is ineffective, then laser surgery or minimally invasive surgery (MIGS) is advised to lower the pressure of the eye(s). Both these treatment modalities are available at The Eye Centre. Furthermore, the centre is equipped with the latest technological equipment to assist in the diagnosis and ongoing management of glaucoma.

What is Glaucoma?

Glaucoma is an umbrella term used to describe several conditions affecting the health and function of the optic nerve which plays an important role in our vision. Damage to the optic nerve as the result of “Glaucoma” is often the direct result of increased intraocular pressure. It is one of the leading causes of blindness in adults over 60, and while it can occur in individuals of all ages, it is more common among the elderly. An insidious condition, the progression of Glaucoma is at such a glacial pace, and causes so few symptoms that the condition is rarely diagnosed until a late stage – at which point significant vision loss will already have occurred. Vision lost as a result of optic nerve damage cannot be recovered at this time. 

What Causes Glaucoma?

Glaucoma is a catch-all condition referring to damage sustained by the optic nerve. There are a myriad of conditions and diseases that can contribute to optic nerve damage, but the development of Glaucoma is almost always associated with increased intraocular pressure, whatever the cause. Increased intraocular pressure is caused by a build-up of fluid (the aqueous humor) in the eye, which can be caused by, for example, excessive fluid production, or an insufficient drainage system. Regardless of the primary cause (production or drainage), Glaucoma appears to be, at least partially, hereditary.

What are the Primary Symptoms of Glaucoma? 

Glaucoma inevitably causes vision loss, whether the onset is acute or not. However, any damage caused to the optic nerve is irreversible, and many people only develop symptoms once the disease is already at an advanced stage. When symptoms do begin to occur, they may include: 

• Patchy/blind spots in your vision (central or peripheral, typically both eyes)
• Tunnel vision (especially in late stages)
• Severe headache
• Eye pain
• Nausea and vomiting
• Blurred vision
• Halos around lights
• Red eyes

Without treatment, Glaucoma will cause blindness. Even with treatment, approximately 15% of people diagnosed with Glaucoma will become blind within 20 years. 

Risks Factors For Glaucoma Treatment

You are at increased risk for developing Glaucoma if you:

• Are over the age of 60
• Have increased intraocular pressure
• Are Black, Asian or Hispanic 
• Have a family history of Glaucoma 
• Have certain underlying medical conditions, including but not limited to diabetes, heart disease, hypertension, and sickle cell anemia
• Have corneas that are thin in the center 
• Are exceptionally near- or farsighted 
• Have suffered a previous eye injury or undergone prior eye surgery 
• Have used certain eye medications, including but not limited to corticosteroids, for an extended period of time

Glaucoma Prevention

As they say, prevention is better than cure – and since optic nerve damage cannot be cured, it is truer in the case of Glaucoma than ever! It is so vitally important to take care of your optic health and have regular checkups and pressure tests to ensure Glaucoma is caught early. If you’re experiencing symptoms, it’s already too late! Steps you can take to ensure you catch Glaucoma as early as possible include: 

• Getting regular dilated eye exams and intraocular pressure tests at your ophthalmologist’s office. 
• Know your family history. As there appears to be a genetic predisposition to the development of Glaucoma, it is in your best interest to take an interest in the ocular health of your immediate family.
• Exercise safely and wear protective eye gear as needed. 
• Take your prescribed medications – whether for an underlying condition or to reduce intraocular pressure before you develop Glaucoma, never skip doses of your prescription medications or adjust your intakes without consulting with your physician. 
• Wear eye protection! Serious eye injuries can lead to the development of Glaucoma. Always wear eye protection when undertaking high-risk activities, including, but not limited to using power tools, or playing sports including paintball, airsoft or indoor enclosed court ball games like racquetball. 

Different Kinds of Glaucoma?

There are two primary types of Glaucoma with which you can be diagnosed.

• Open-Angle Glaucoma
• Angle-Closure Glaucoma

The first is the most common type of the disease, and refers to Glaucoma caused by increased intraocular pressure due to the partial blockage of the drainage system of the eye. In Open-Angle Glaucoma, the drainage angle formed by the iris and cornea remains open, but the trabecular meshwork proves blocked, whether partially or, ultimately, completely. This causes the pressure in the eye to build slowly, so that the onset of symptoms is at a glacial pace. Open-Angle Glaucoma tends to cause irreparable vision loss before the disease is diagnosed as patients delay the seeking of treatment until symptoms become severe, meaning that the disease has already progressed. 

In Angle-Closure Glaucoma, the drainage angle formed by the cornea and iris is too narrow to allow drainage due to a bulge in the iris which narrows and/or blocks the drainage angle. Some people have a predisposition to Angle-Closure Glaucoma as they have naturally more narrow drainage angles. This iteration of the disease can be acute, and strike without warning, or can develop gradually like Open-Angle Glaucoma. Acute Angle-Closure Glaucoma is a medical emergency and urgent care is needed to prevent complete loss of vision. 

Atypical Glaucoma? 

Atypical presentations of the disease include Normal-Pressure Glaucoma, Glaucoma in children, and Pigmentary Glaucoma. In Normal-Pressure Glaucoma, the disease develops despite an intraocular pressure that is well within normal limits. This may be due to an underlying medical condition which affects your circulation or may be due to an overly sensitive optic nerve. Glaucoma in children, though rare, is not unheard of, and babies can even be born with congenital Glaucoma, in which case the disease is typically caused by an underlying medical condition which will need to be treated in an effort to preserve eyesight. Pigmentary Glaucoma is often difficult to diagnose as instances or experiences of increased intraocular pressure can be transient. Certain activities like jogging can disturb built-up pigment in the eye, depositing it onto the drainage mesh and causing intermittent intraocular pressure elevations. Therefore, Pigmentary Glaucoma can be described as occurring when pigment granules from the iris build up and block the drainage mesh in the angle formed by the cornea and iris. 

Treatment Options for Glaucoma

Optic nerve damage, once caused, cannot be reversed. That means that any degree of vision loss you have already suffered by the time you consult your ophthalmologist will be permanent. That is why it is so important to see your doctor for regular checkups. If caught early, intraocular pressure can be treated to prevent further damage to the optic nerve and to prevent the development of Glaucoma. 

Depending on the severity of your Glaucoma and the type with which you are diagnosed, treatments to prevent the progression of the disease may include: 

• Medicated eye drops
• Oral medications
• Laser treatment
• Surgery
• Or any combination of the above.

 

For more information on Glaucoma, you can visit any of the sites listed below. Alternatively, or if you are actively seeking diagnosis and/or treatment, you can contact The Eye Centre directly to book your consultation with one of our resident ophthalmologists – because we care about eye care.

Glaucoma causes & symptoms – by Mayo Clinic

Glaucoma Eye Health – by WebMD

Symptoms of Glaucoma – Glaucoma.org