• EnChroma Cx-D is for individuals who have difficulty differentiating colors due to deuteranomalous color vision deficiency. This condition, which affects about 7% of males worldwide, causes problems distinguishing green from brown, green from yellow, and pink from gray.
• EnChroma Cx-PT is for those who have decreased red sensitivity because of protanomalous color vision deficiency. This condition, affecting 1% of males worldwide, causes difficulty differentiating red and brown, green and orange, and purple and blue.
• EnChroma Cx-NRG enhances the intensity of all colors for individuals with normal color vision.
• EnChroma Cx-UV450 offers comprehensive protection from ultraviolet and short-wavelength blue light. It is ideal for individuals who are exposed to high-intensity sunlight (such as those in aviation, marine, and alpine environments), at-risk patients who seek extra protection from blue-light radiation, or patients with low vision due to cataracts or glaucoma.

UVA vs. UVB

 The sunlight that reaches us is made up of two types of harmful rays: long wave ultraviolet (UVA) and short wave ultraviolet (UVB).  UVA rays are basically responsible for aging of the skin, and UVB rays mainly produce sunburn.  Both can be harmful to the eyes and eyelids.  

Sunglasses are a must if you spend significant time outdoorsand not just on sunny days.  Overcast days have just as harmful UV rays.   

Most people believe that the darkness of the lens is what protects their eyes. The degree of darkness has no effect on UV rays. For adequate protection, look for sunglasses that indicate they block 100 percent of the sun's UV rays.  This includes those labeled as "UV 400," which blocks all light rays with wavelengths up to 400 nanometers. (This covers all of UVA and UVB rays.)  Wrap-around styles offer the most protection, preventing rays from entering around the frame. 

Sunglasses don't have to be expensive, most over the counter sunglasses are under $20 and many provide the necessary UVA/UVB protection. 

Rebecca Mueller, O.D.

The winter months can be especially harsh on your eyes. Learn how to care for your eye health this season by identifying and preventing certain issues. 

• Drink extra fluids
• Use a humidifier indoors 
• Wear glasses outdoors to shield eyes from cold wind

• Wear sunglasses in the winter, especially when the ground is covered in snow, to protect the eyes. 
• Wear sports goggles.  Skiing, snowboarding, biking, etc. require safety goggles with UV protection to shield the eyes from freezing winds and sun exposure.  
• Limit your time outdoors 

The Vision Council produced a report, finding that without protective measures, residents of some U.S. cities are at “very high or extreme risk” for ocular or skin damage as a result of Ultraviolet (UV) radiation at least one day out of every four.

In “Hidden Dangers of UV:  Keeping Your Eyes Safe”, The Vision Council report notes that 58 cities indexed by UV levels by the National Weather Service,  details the factors that can increase exposure risks, discusses forecasts that reveal the intensity of solar UV in cities across the country, and offers tips for preventing UV-related vision problems.  The report cites certain “surprise” UV-intensive cities, such as Wichita, KS; Boise, ID and Norfolk, VA.

Informative tips for choosing sunglasses, lens color, designs for maximum coverage and more are included in this report.  To read the report, visit www.thevisioncounscil.org/sunglasses.

“Report:  Many US citites have “extreme” UV levels” EyeWorld Weekly News June 6, 2011

Cynthia Matossian, MD

Think big.  Think curved.  Too much light around the frame edges can defeat the best sunglasses.  Curved lenses reduce the risk of a foreign body blowing into your eye.

Polarized lenses do the best job of reducing glare.  Anti-glare coatings are less effective and are harder to keep clean.

UV blocking capability provides added safety and offers some protection for macular degeneration and early cataract patients.

Tinting is highly personal and often reflects a fashion statement.  Neutral Gray gives the most realistic color rendition.  Blue Blocking tints add contrast.  Yellow adds transparency thru water.

The amount of tint depends on your individual sensitivity and your personal need to reduce the amount of light.  Do not let someone tell you how dark the tint should be.  Let them show you the various degree of tinting out of doors on a sunny day.

Michael E. Starrels MD