- What is Glaucoma?
- What are the Risk Factors for Glaucoma?
- What are the Symptoms of Glaucoma?
- What are the Two Main Types of Glaucoma?
- How is Glaucoma Diagnosed?
- What are the Treatments for Glaucoma?
What is Glaucoma?
Glaucoma is a group of conditions that usually result in a specific type of optic nerve damage known as optic nerve cupping. Once significant optic nerve loss has occurred patients develop visual field loss in their peripheral vision which can progress centrally ("tunnel vision").
Optic nerve damage and visual field loss is permanent. The optic nerve is the cable cord connecting the eye and the brain. Once the cord is damaged the brain has no signals resulting in vision loss.
Most of the time glaucoma is painless and patients do not have symptoms of vision loss until late in the end-stage of the disease. Early detention and treatment of glaucoma helps in preventing further damage and visual field loss.
What are the Risk Factors for Glaucoma?
Risk factors for glaucoma include the following:
- Older age
- Family History
- African, Hispanic, or Asian ethnicity
- Thin Cornea thickness
- Elevated Eye pressure
- Myopia (near sighted)
- Hyperopia (far sighted) for Narrow angle glaucoma
- Use of Steroids (oral, IV, inhaler)
- Eye Trauma
- Hypertension (high blood pressure)
- Hypotension (low blood pressure)
- Migraines, Vascular spasm, Raynaud's phenomenon
- Sleep Apnea
What are the Symptoms of Glaucoma?
Most patients with glaucoma will not have any symptoms in the early stages of the disease.
Patients with advanced stage glaucoma will have tunnel vision and issues with peripheral vision.
Patients with angle closure glaucoma will have symptoms of:
- eye pain
- red eye
- nausea and vomiting
- decreased vision
- loss of vision
What are the Two Main Types of Glaucoma?
Open Angle Glaucoma
Patients have open angle glaucoma when their drainage system, the trabecular meshwork, is open, unobstructed, and visible on exam. Glaucoma results from the resistance to outflow and the build up of eye pressure.
Narrow Angle or Angle Closure Glaucoma
Angle closure glaucoma occurs when the drainage system of the eye, the trabecular meshwork, is blocked or obstructed (usually by the iris) and fluid can not drain from the eye resulting in increased eye pressure.
How is Glaucoma Diagnosed?
Glaucoma is diagnosed during a comprehensive eye exam. It may take a couple of visits and special testing to determine if a patient has glaucoma.
What Can I Expect During the Glaucoma Exam?
- Visual acuity testing
- Ocular vital signs
- Eye pressure
- Pupil testing: Confrontational fields, Extraocular movements
- Slit Lamp Exam & Dilated Eye Exam
- Fundus Photos of the optic nerve.
- Gonioscopy (special lens placed on eye): determines if you have narrow angles or open angles.
- Humphrey visual field: a device that measures and maps a patient's visual field.
- Optical Coherence Tomography: a noninvasive device that uses light to create cross section images of the optic nerve. It detects changes in optic nerve thickness over time and compares the patient's optic nerve to their normal cohort.
Patients with glaucoma are typically followed between every 2 to 6 months depending on the severity. Sometimes patients are followed for shorter duration, 1 to 8 weeks, depending on their ocular situation and response to treatment.
What are the Treatments for Glaucoma?
The initial treatment for glaucoma is topical medication. Some medication reduces aqueous humor production and others increase outflow of the drainage system.
- Prostaglandin Analogs
- Alpha agonists
- Carbonic Anhydrase Inhibitors (topical and oral)
- Rho-Kinase Inhibitors
- Cholinergic Agents
- Laser Iridotomy: A procedure for patients with narrow angles/ narrow angle glaucoma. The laser creates a hole in the peripheral iris to prevent pupillary block and acute angle closure glaucoma.
- Laser Trabeculoplasty: A procedure for patients with open angle glaucoma, who have issues taking eye drops (compliance or allergy). The laser targets the Trabecular meshwork for 180 to 360 degrees depending on the surgeon. This procedure improves outflow to reduce eye pressure. The effect of the laser can last up to 1 to 5 years and can be repeated, but loses its effectivity over time.
- Traditional Glaucoma Surgery
- Trabeculectomy: A procedure where a tiny scleral flap is created to improve outflow in glaucoma patients. This surgery creates a filtration bleb or conjunctival buble under the eyelid.
- Glaucoma Drainage Device: A procedure where a tube implant is placed inside the eye (anterior chamber) to improve outflow. This tube is connected to a reservoir plate that will be sutured in between a patient's eye muscles.
- Minimally Invasive Glaucoma Surgery