Guest Post, Health

Healthy Vision Month: Cataracts

By Aparna Mani, MD, PhD
MGH Medical Walk-In Unit

Aparna Mani, MD, PhD

Much like with a camera, the lens of the human eye helps to bring the image  you’re looking at into focus.  The lens measures in length about half the diameter of a dime and is made of a gel-like protein called collagen. Through the work of thin muscle fibers, the lens changes its shape to bring objects into focus.  With age, pigment can collect and cloud the crystal clear lens resulting in vision loss. This clouding of the lens, called a cataract, is the leading cause of blindness worldwide.  Since the normal aging process is one of the main causes for cataracts, we are all at risk for developing cataracts.  However, people with diabetes, those who use corticosteroids for an extended period of time (for instance as treatment for asthma or arthritis), who smoke, or have a family history of cataracts are at increased risk.

Though painless, the presence of a cataract may cause symptoms such as increased glare from lights, difficulty with night driving, difficulty reading, and reduced ability to appreciate colors. The severity of these symptoms can increase over time and begin to impact one’s lifestyle. Though your health care provider may be able to pick up the presence of a cataract during a routine visit using an ophthalmoscope, you will need a comprehensive exam and detailed vision testing by an ophthalmologist to fully assess a cataract. Recommendations on management and treatment is based on this assessment.

Currently, the only treatment for cataracts is surgery, normally done in an outpatient setting.  Depending on the degree of the cataract and its impact on vision, the ophthalmologist may recommend observation and follow up vision testing for a period of time, or proceeding with surgery to treat the cataract.  With surgery, the clouded lens is removed and replaced with an artificial one made of plastic or silicone to restore vision. Results are usually apparent right away within hours to a few days of post-operative healing.

Though there is no proven therapy to reduce or slow the progression of cataracts, some studies have suggested that eating a healthy diet rich in fruits, vegetables and vitamins such as lutein is associated with a lower risk of developing a cataract. In addition, since smoking is a risk factor for cataract development, quitting tobacco use may help prevent cataract formation.

Guest Post, Health

Healthy Vision Month: Glaucoma

By Aparna Mani, MD, PhD
MGH Medical Walk-In Unit

Aparna Mani, MD, PhD

Eyesight develops from the initial rudimentary flickers of a newborn to the full kaleidoscope of adult vision over the first three to five years of life. Our sense of vision has such a powerful impact on how we define ourselves, our loved ones, and the world in which we live.  Yet it’s one sense that can slowly slip away as we age.  Glaucoma and cataracts are two of the most common causes of vision loss and blindness in the aging adult population. But here’s some good news:  both conditions are treatable when caught and acted on early.  I will look at both in depth, starting today with glaucoma and continuing next week with a discussion on cataracts.

Glaucoma is a disease of increased pressure in the eye leading to damage of the optic nerve – the nerve that carries all the visual information our eyes pick up to the brain where it is interpreted. Think of the eye as a fluid filled, globe-like structure with the optic nerve exiting the back like the electrical cord on a toaster or TV. If the flow of fluid in the eye is not kept in balance, increased fluid pressure can develop inside the globe leading to compression and irreversible damage to the optic nerve.  There are two main types of glaucoma:  open angle, which accounts for approximately 90% of the glaucoma in the United States, and closed or narrow angle glaucoma.

Open angle glaucoma affects about 1 in 200 people over the age of 50.  A slow, chronic process, this type of glaucoma develops over a number of years. In fact, open angle glaucoma is often called the ‘silent thief of sight’ because of its painless presentation. However, once vision loss sets in, it is progressive and irreversible. People at increased risk for glaucoma include those with a family history of the disease; African Americans and Latinos; and people with heart disease or diabetes.   The risk of developing glaucoma also increases with age for everyone, regardless of whether they have any of the above risk factors.

So if glaucoma is “silent” how can you detect changes in time for treatment to be effective? Your health care provider can detect early changes with an eye exam before noticeable vision changes develop. In addition to examining the optic nerve, they will do a formal visual field test, measure intraocular pressure (fluid pressure in the eyes), and observe for any changes in eye size and shape. Although there is no cure for glaucoma at this time, early detection and initiation of treatment can help halt or slow down the progression of the disease. Treatment may entail prescription topical eye drops, laser therapy, or surgery. If you are prescribed eye drops for glaucoma, it’s crucial you take them as directed —not keeping up with treatment is a major reason for progression to vision loss. The American Diabetes Association also recommends seeing an eye care professional (either an ophthalmologist or optometrist) for a comprehensive eye exam at least once a year.  Don’t hesitate to ask if your provider is familiar with identifying and treating glaucoma and other diabetes eye conditions.

In contrast to the quiet and slow progression of open angle glaucoma, closed angle glaucoma is a medical emergency. Closed angle glaucoma presents with sudden vision loss and pain that often prompts one to seek medical care right away. In addition, a person may experience any of these symptoms:  seeing halos around lights, nausea and vomiting, developing a red eye and/or a fixed and dilated pupil. Again, this form of glaucoma is considered a medical emergency – if you experience any of these symptoms seek medical attention immediately.