What You Need to Know About Glaucoma

Glaucoma

Introduction ^1,2

The optic nerve is the structure that connects the eye to the brain. Glaucoma is an eye condition that damages this structure and may result in vision loss. Glaucomatous vision loss is irreversible. Glaucoma is often associated with elevated eye pressures, but sometimes glaucoma occurs with normal pressures as well. Patients may have one or more risk factors that can lead to the development of glaucoma. Early diagnosis and treatment play a crucial role in blindness prevention.

Glaucoma is the second leading cause of irreversible blindness in the USA in the adult population. African Americans have a 3-6 times higher risk of getting glaucoma than caucasians. Some types of glaucoma develop more often in some ethnicities than others. There are 60 million people with glaucoma worldwide. 

Glaucoma is a silent disease; timely follow-up and prompt care are essential for a good prognosis. Therefore, it is recommended the patients are informed of risk factors, signs, symptoms, and importance of follow-up.

Types of Glaucoma ²

• Primary open-angle glaucoma 
• Primary angle closure glaucoma
• Secondary open-angle glaucoma 
• Secondary angle closure 
• Normal tension/pressure glaucoma 
• Congenital Glaucoma

Causes of Glaucoma ¹

The exact cause of glaucoma is unknown but there is a relationship between elevated eye pressure and open-angle glaucoma. The eye is constantly producing fluid internally, called aqueous humor, and this fluid passes through the internal drainage systems of the eye. The balance of fluid production and drainage is what produces your eye pressure.  Glaucoma develops when there is resistance to aqueous fluid drainage. This outflow obstruction leads to a gradual rise in eye pressure which causes damage to the optic nerve, and subsequent vision loss. Other mechanisms that may lead to glaucoma involve compromised blood flow to the optic nerve due to elevated eye pressures. 

Signs and Symptoms of Glaucoma ^1,2,3

Many patients with open-angle glaucoma are unaware that they have the disease until advanced stages of the disease. Some patients discover this condition during routine examinations and others notice decreased peripheral vision. 

Patients with acute angle closure glaucoma usually develop the following dramatic symptoms:

• Headache
• Pain in the eyes
• Red eye
• Blurring of vision
• Nausea
• Vomiting 
• Halos

Patients with secondary glaucoma usually have a history of usage of certain medications like steroids, previous eye surgery, trauma, or chronic health illness. 

Diagnosis of Glaucoma ¹

Your ophthalmologist will perform the following when glaucoma is suspected:

• Obtain a detailed history, including ocular trauma, eye surgery, medication usage, or any chronic diseases e.g diabetes mellitus
• Visual acuity
• Tonometry (eye pressure monitoring)
• Gonioscopy (visualization of the ocular drainage system)
• Pachymetry (measure of corneal thickness)
• Complete dilated eye exam
• Visual field testing
• Optic coherence tomography
• Retinal scan
• +/- lab testing to rule out chronic illnesses 

The diagnosis of glaucoma requires a high level of expertise to evaluate clinical findings and testing results. 

Management of Glaucoma ^1,3

The management and treatment of glaucoma depend on its type and underlying cause. However, keep in mind there is no treatment to reverse the visual damage that has already occurred. Treatment aims to reduce and prevent further damage. Treatment aims to lower the pressure, either with medications, laser, or surgery. Patients with glaucoma require regular follow up including frequent testing to monitor for progression. 

Open-angle glaucoma is generally managed with the following classes of eye pressure-lowering drugs:

• Beta-blockers
• Carbonic anhydrase inhibitors 
• Prostaglandin analogs
• Alpha 2 receptor agonists
• Nitric oxide producing drugs

Angle-closure glaucoma is an ocular emergency and requires prompt measures:

• Intraocular pressure-lowering drugs
• Laser peripheral iridotomy
• Proper follow-up once the acute phase has settled 

Glaucoma secondary to underlying causes should be treated by correcting the underlying disease. Glaucoma is commonly slowly progressing and is a lifelong condition. Patients should live healthy lifestyles including eating a balanced diet. They should avoid smoking, excessive caffeine, and drugs that raise eye pressure. 

Glaucoma is a silent and slowly progressing disease of the optic nerve associated with elevated intraocular pressure. Early diagnosis and treatment are critical to prevent permanent loss of vision. Checking eye pressure is standard at every follow-up along with fundoscopy to visualize the optic nerve. It is highly recommended that patients should have regular checkups from their ophthalmologists. Book your appointment with a glaucoma specialist at Eye Surgeons Associates.

 References:

https://www.ncbi.nlm.nih.gov/books/NBK538217/

https://www.webmd.com/eye-health/glaucoma-eyes

https://emedicine.medscape.com/article/1205421-overview 

Author

Eye Surgeons Associates Drs. Zuhair H. Peracha, Manal H. Peracha-Riyaz, Eric Zuckerman, Matthew Pieters, and Leila Siblani are dedicated to excellence in eye care and service. We utilize the latest treatment methods and procedures, including routine eye care, cataract surgery, glaucoma treatment, retinal disease management, diabetic eye treatment, and eyelid surgery.