National Glaucoma Month

Bitterroot Valley Eye Associates
A Service of Marcus Daly Memorial Hospital
Mark Calderwood, MD
300 North 10th Street
Hamilton, MT 59840
(406) 363-5434

In observance of national glaucoma month, this article will discuss one of the more obscure but relevant eye diseases that cause a significant number of people to lose vision permanently. There are about 2.5 million Americans affected by glaucoma and 200,000 new cases per year. That number is increasing. Yet for most, glaucoma is very treatable if caught early through screening. So what is glaucoma?

Glaucoma is a group of disorders that cause damage to the optic nerve in the eye from abnormal pressure. The optic nerve, found in the back of the globe, is the structure which transmits images from the retina (like the film in a camera) to the brain. Once the damage is done it's gone forever. There is no way to reverse it. That's why it's imperative to catch it early. And the only way to catch it early is to be checked regularly by your eye doctor because most people are unaware they have it until the damage is very advanced. Most forms are totally asymptomatic. Though many people think of glaucoma as a disease that affects peripheral or side vision, it can affect any area of vision and in fact can affect the central vision early on.

There are a number of different forms of glaucoma. The most common is called chronic open angle glaucoma or COAG. The damage to the nerve comes from long term high pressures in the eye for certain patients. We used to believe there was a range of normal pressures (10-21 mmHg). However, as time has gone by we realize some people can withstand high pressures, while others are very sensitive to lower pressures. It is very individualistic. And often it can take years to determine if the patient actually has glaucoma, because early on the changes can be very subtle. There is currently no single test to make a diagnosis. There is no blood test.

Usually serial eye pressures, pictures, viewings, and visual fields (an office test checking for the whole vision of each eye peripherally and centrally) are taken. Family history can also play an important role. Therefore, if it runs in your family you should be checked regularly.

If you have COAG, there are a number of treatment options. The most common treatment is with a variety of eye drops. These medications have become very effective and for most people can control the disorder very well with minimum to no side effects, but it does require trial and error to determine which works best for each patient. Alternative treatment includes laser treatments called ALT or SLT. These can be used as first line therapy, adjuncts to therapy, or alternates if meds fail. In progressive disease with use of the aforementioned treatments, more invasive and risky surgical options (trabeculectomy or stents) may be required. These are typically performed by a glaucoma specialist.

Other forms of glaucoma include angle closure, pigmentary, pseudoexfoliation, neovascular (diabetes the most common cause), congenital, traumatic, and low pressure or normal tension glaucoma. These are much less common and have different treatment modalities. Feel free to discuss these with your eye doctor.

So what do we recommend? If you have a family history of COAG you should start getting screened every two years at the age of 40. With no history we recommend testing annually after 60. Demand that you get tested with non-airpuff techniques which are far more accurate and reproducible. The most common reason for progression of disease is noncompliance with medications. The most important thing however is to become educated, informed, and screen regularly. With proper treatment and follow up glaucoma can be controlled instead of controlling.

Warm up in style with new eyeglass frames from Bitterroot Valley Eye Associates! Get 15% off all eyeglass frames at Bitterroot Valley Eye Associates' Optical Center from January 1, 2016 to January 31, 2016 with coupon. Visit for coupon and more information. Walk-ins welcomed.

Questions and or comments regarding this week's health column please contact, Mark Calderwood, MD at Bitterroot Valley Eye Associates, a service of Marcus Daly Memorial Hospital, 300 North 10th Street, Hamilton, MT 59840. Working together to build a healthier community!


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