Dr. Guy Eakin: Hi! I'm Dr. Guy Eakin, Vice President of Scientific   Affairs for the American Health Assistance Foundation. Today, I'm going   to talk about glaucoma, the leading cause of irreversible vision loss   and ultimately blindness.<br /><br />


Worldwide,   there are an estimated 17 million people who are visually impaired due   to glaucoma and an estimated 7 million people are blind. <br /><br />


Before I   begin discussing what glaucoma is, let me tell you a little bit about   myself. I have a doctoral degree and many years of experience in   research at two of the nation's top research centers. <br /><br />



The   American Health Assistance Foundation is dedicated to funding research   and providing free information to the public about glaucoma as well   macular degeneration and Alzheimer's disease. There is helpful   information available on the website at www.ahaf.org and the American   Health Assistance Foundation, we're proud to say, has awarded over a   $110 million in grant money worldwide. <br /><br />


This money is used to   support the work of scientist and doctors worldwide who are seeking   treatments and cures for these three age related diseases. Glaucoma,   although commonly referred to as one disease, is actually a group of eye   disorders. What each of these different types of glaucoma has in common   is that each leads to damage of the optic nerve which is the bundle of   nerve fibers that carry information from the eye back to the brain. <br /><br />


Damage,   to the optic nerve, can lead to vision loss and ultimately to   blindness. Many people believe that glaucoma is defined as having   elevated pressure inside the eye however elevated pressure alone does   not define the disease. <br /><br />


Instead, elevated eye pressure can be   thought of as a leading risk factor for development of the disease. So,   to understand how the eye pressure impacts the development of glaucoma,   it's important to understand how the eye works. <br /><br />


<b>The eye   constantly makes a fluid called aqueous humour which helps maintain   normal eye pressure and provides nutrients to the cornea and the lens of   the eye. The aqueous humour circulates inside the front of the eye and   primarily drains the vaporous structure called the trabecular meshwork.<br /><br />


You   can think of the trabecular meshwork as being similar to the drain   holes or grate in your shower. Normally, there is a balance between the   amount of fluid made and the amount that leaves the eye. If this balance   is not achieved, then pressure builds up inside the eye, similar to a   sink that packs up when the drain is blocked. <br /><br />


This pressure   increase may eventually cause damage to the optic nerve and loss of   vision. It's this characteristic damage to the optic nerve and vision   loss that defines glaucoma. However, it depends on the type of glaucoma   you have is to what is actually happening in your eye.<br /><br />


There are   many different types of glaucoma. The most common type of glaucoma is   open-angle glaucoma. The majority of the other types of glaucoma are   closed-angle glaucomas which can be chronic or acute. Open-angle   glaucoma has no symptoms in the beginning however is a progressive   disease characterized by optic nerve damage. <br /><br />


High eye pressure is   the most significant recognized risk factor for the development and   progression of the disease, although, glaucoma can occur in people with   normal eye pressure. As the pressure gradually builds and is left   untreated, the optic nerve accumulates damage resulting in the loss of   peripheral or side vision. And without treatment, the result will be   total blindness. <br /><br />


<b>Closed-angle glaucoma comes in two forms; acute   and chronic. Acute closed-angle glaucoma is a sudden medical emergency   that must be treated immediately because blindness can result in a very   short amount of time. <br /><br />


The most common type of angle closure is   known as pupillary block. In pupillary block, the normal flow of the   aqueous humour from an organ called the ciliary body to the trabecular   meshwork, that we've talked about earlier, is blocked when the iris and   lens touch. Symptoms may include severe pain, nausea, vomiting and   blurred vision. <br /><br />


The patient may also see colored halos around   lights. Chronic closed-angle glaucoma progresses slowly and can produce   damage without symptoms similar to open-angle glaucoma. As I've   mentioned earlier, sometimes glaucoma can occur when the pressure inside   the eye is normal. <br /><br />


This condition is called normal tension   glaucoma. The causes of optic nerve damage, when the pressure is normal,   are not well understood, thus there is a need for more research into   the causes and treatments of specific types of glaucoma. <br /><br />


There   are however some known risk factors for normal tension glaucoma. So   these include cardiovascular disease, high blood pressure, having a   family member with glaucoma or being a female or being of Japanese   ancestry. It is important to remember that glaucoma is actually several   diseases with different prognoses and treatments. <br /><br />



The only way to   know if you have any of these types of glaucoma is to visit your   doctor, only through a thorough examination will an accurate diagnosis   can be made and sight saving treatments can be prescribed. If you want   to learn more about glaucoma, check out our other videos include   understanding your risk factors.