Archive for the ‘Eye Care’ Category
Your prescription has changed and you need a new pair of eyeglasses.
So you take a little trip down to your local optometrist’s office. You’ve been getting your eyeglasses there ever since your first-grade teacher noticed you were squinting at what she wrote on the blackboard.
You go in and look around. You check out the frames. They’ve got all the cool retro wayfarer styles everyone’s wearing. Then you look at a price tag. All of a sudden you have a bad case of sticker shock.
My eyes must be really bad, you think. That can’t say what I think it says. More than $300? Just for the frame?
You ask the optician, who confirms your worst suspicion. Not only that, he gives you a look like he’s saying, if you have to ask how much these glasses cost, you can’t afford them.
That’s it, you say to yourself, after slinking out of there with your hand on your wallet. I’ve had it with these brick-and-mortar eyeglasses stores, where the price gouging feels more like eye gouging. I’m finally going to do it. I’m going to order glasses online, and save all that money I’ve been hearing about.
You’ve just made a decision worth hundreds of dollars. Maybe even thousands in the long run. It’s true. If you shop carefully online, you’ll find prices for discount eyeglass frames and lenses so low you could buy high-quality, stylish eyeglasses for your whole family online for what it would cost to buy just one pair for you locally.
But there’s a major pitfall to avoid when you order glasses online.
How can you make sure the glasses you buy over the internet will fit you if you can’t try them on before you buy them?
That’s a great question. We have an even better answer.
Here is how to make sure the glasses you buy online will fit you well when they come in the mail, and you take them out of the package and try them on.
First, if you already have a pair of eyeglasses that fits you well and looks good on your face, you’re ahead of the game.
All you have to do is get the frame dimensions from these eyeglasses, and order a pair online that matches those dimensions.
It doesn’t even have to be an exact match. All eyeglass frame dimensions are listed in millimeters. A millimeter is a tiny unit of measurement. There are 25.4 millimeters to an inch. So you have a leeway of a few millimeters on each element of a frame.
Those elements are:
The bridge. This is the part of the frame that goes across the bridge of your nose. That’s why it’s called the bridge.
The temple arm. Those are the parts that connect to the front of the frame on either side of your head and rest behind your ear. Sometimes people call the temple arms “legs,” “stems,” or even “bows,” but in the optical industry they’re called temple arms, because they are next to your temple.
The lens width. This is the diameter of one lens, measured at the widest part. It’s also called the “eye size” in the optical industry, which doesn’t make a lot of sense, because it’s not the measurement of the size of your eye; it’s the measurement of the width of your eyeglasses’ lens. We’re mentioning this because sometimes eye doctors will suggest frame dimensions and write these on your prescription. When they do, they may write “eye size” on the prescription when they mean the lens width. So don’t worry about matching that number with the size of your eye. It’s the width of one eyeglass lens.
The lens height. This is measured just like the lens width, but vertically, not horizontally. If your prescription includes an NV-ADD (Near-Vision reading ADDition) number, you can order bifocal or progressive glasses. This is where the lens height measurement becomes crucial: The lens height must be at least 30 millimeters to accommodate a bifocal or progressive prescription.
The frame width. This is the most important measurement on a frame to determine whether it will fit you well and look good on your face. It’s the measurement of the entire front of the frame, from the point that sticks out farthest on the left, to the point that sticks out farthest on the right. Or vice versa.
Remember when we said that if you have a pair of glasses right now that fits you well and looks good on your face you are ahead of the game? Well, you’re rounding third and heading for home if on the inside of one of your temple arms you have three numbers, which are the dimensions of, in order, the lens width, the bridge, and the temple length.
Most of the time, if the numbers are stamped on the inside of the temple arm, they will be listed the way they are in the first example, on the left. (Ignore the first number on the temple arm that precedes these numbers; that will just be the manufacturer’s model or stock number.)
After this model or stock number, the lens width comes first, the bridge is next, and the temple arm is last. Sometimes it could be listed the way it is in the second example, on the right, with the temple arm length first, the lens width next, and the bridge last. Either way, there will usually be a little square between the first and second numbers.
You may even see a pair of glasses that has these numbers stamped or engraved on the inside of the bridge, but this is rare.
If you have the numbers stamped on the inside of the temple arm or on another element of the frame, the only other measurements you need are the frame width and the lens height.
If you don’t have numbers stamped on the inside of the temple arm, you can measure the dimensions of your frame elements with a millimeter ruler. Don’t have a millimeter ruler? Not a problem; you can get one at any drug or dollar store. However, if you have a cloth tape measure with millimeter hash marks, this would be the best measuring tool to use, especially when we come to the temple arm measurement.
Here’s how to measure each element we discussed:
The bridge. Measure horizontally, at the top of the bridge, from the edge of one lens to the edge of the other lens. The part of the frame that holds the lenses in place will be included in the measurement, since you’re measuring from lens edge to lens edge, not frame edge to frame edge.
The temple arm. This is the measurement for which a cloth measuring tape with millimeter hash marks would come in handy. Here’s why: The temple arm is measured from the hinge – where the temple arm connects to the front of the frame – all the way back to the tip.
The measurement includes the bend around the ear, which is why a cloth tape measure is useful for this measurement. If you have a cloth tape measure, you can measure the curve easily. If you’re using a plastic or wood straight-edged ruler, it would be best to do the measurement in two parts.
Start at the hinge, measure to the beginning of the bend, and write that measurement down. Then go back to where you left off, right at the beginning of the bend. Measure the last part, which is angled, to the tip. Add the two sectional measurements together, and that’s the total temple arm length.
You may have a pair of glasses with cable temple arms, the kind that curve around your ear. (pictured above)
If you don’t have a cloth millimeter tape measure, you could print out the downloadable PD ruler at the Zenni Optical website, www.zennioptical.com:
You can use this paper ruler to measure the cable temple arm. Or you could cut a strip of paper about a half-inch wide and 10 inches long. Mark the little paper strip where you begin measuring the temple arm at the hinge. Curve the paper strip around the curve of the temple arm and mark it where the temple arm ends. Stretch out the paper strip and measure the length with a millimeter ruler. That’s your cable temple arm length.
The frame width. Again, it’s the entire horizontal measurement of the front of the frame, measured from the part that extends farthest outward on one side to the part that extends farthest outward on the other side. A metal frame may have a little piece that sticks out on the side toward the top, like the part that extends from the outer edge of the lens on a pair of rimless glasses, just before bending to meet the hinge of the temple arm, such as on this rimless frame:
If you do have a frame such as this one, or any frame with a piece that sticks out on the side, you would include that part of the frame, on each side, in your measurement of the frame width. Whether a frame is too big, too small, or just right for your face is mostly determined by the frame width. Also, make sure you do this measurement at the front of the frame. You don’t need to measure the distance between the two temple arms at the back of the frame.
The lens width. If the width of the frame you are shopping for online matches within two or three millimeters the width of the frame you have that fits you well, you can be confident that the frame you see online will fit you just as well. But be aware of the lens width: even though the total frame width might match the width of your frame, the lens width might be a little narrow or wide for your pupillary distance, which is the measurement of the distance between the middle of each pupil. This measurement determines where to place the optical center on each lens.
The lens height. This is measured just like the lens width, but vertically, not horizontally. Once again, the lens height must be at least 30 millimeters to accommodate a bifocal or progressive prescription. In addition, pay attention to the lens height, because this is an important factor in determining how the glasses will look on your face. If you get a frame with a tall lens height, something over 36 millimeters, the glasses may look too big for your face. Conversely, a too-short lens height, lower than 30 millimeters, may not provide all the corrected-vision coverage your eyes need.
Once you have the measurements of your frame, you can shop for a frame online that will fit you.
Remember, you have a leeway of a few millimeters on each element, with a caveat: Stick to no more than two millimeters higher or lower on the bridge. For example, if your perfect bridge measurement is 18 millimeters, you can go as low as two below that, 16 millimeters, or as high as two above, 20 millimeters. Therefore, a bridge that’s anywhere between 16-20 millimeters should fit you just fine.
Also, if you’re getting a frame with adjustable nose pads, this gives you even more leeway, because the nose pads can be adjusted for the best fit. Pinch them closer together to make the bridge fit more snugly and rest higher on your nose; spread them apart to loosen the fit and let them rest lower on your nose.
On the frame width, lens width, and lens height, you should be fine with a leeway of three millimeters. Therefore, if your perfect frame is 135 millimeters wide, frames between 132-138 millimeters should fit you just as well.
Since many temple arms are adjustable at the curve where the temple arm bends behind your ear, you have a leeway of as many as four millimeters. In that case, if the temple arm on your eyeglasses is 140 millimeters, you will be fine with a temple arm that falls between 136-144 millimeters. However, many temple arms are not adjustable, especially those made of aluminum alloy, titanium, memory titanium, and memory plastic. Check the temple arm material listed in the description of the frame to be sure. Also, look at an enlarged picture of the online glasses. If you can see that embedded in the temple arm is a stainless steel rod, you can be confident that this frame’s temple arm is adjustable.
Here are a few more things to keep in mind. The vintage styles from 50 years ago and more that are popular today were often worn much smaller than glasses are today. This is because lenses were made of glass then, and the heaviness of glass caused eyeglasses manufacturers to keep the lenses as small as possible.
Conversely, eyeglasses in the ’70s were frequently oversized, such as these worn by the late Hollywood super-agent Irving Paul Lazar:
Another thing to keep in mind is how strong your prescription is. If you have a strong prescription, +/- 6.00, the wider and thicker your lenses will be, on the outer edge with a minus sphere (nearsighted) prescription, in the middle with a plus sphere (farsighted) prescription. Therefore, if you have a strong prescription you may want to stick with lens widths that are lower than 50 millimeters.
Friday, December, 6 2013 by Matthew Surrence
Diabetes is known as a condition that affects your blood sugar levels, potentially affecting many body systems, including your eyes. If you have diabetes, or are at risk of developing the condition, it’s important to monitor your vision for any changes, as diabetes can lead to several eye conditions that may result in both pain and vision loss.
Here are some eye conditions that are associated with diabetes:
Diabetes can affect the blood vessels in the eye, causing leaking or blockages. This can damage to the retina, leading to vision loss. Once discovered, there are several treatment options, although good management of your diabetes can make a significant difference in the severity of the condition. Laser surgery can treat the blood vessels in your eye and other surgical options exist for more advanced retinopathy.
A cataract is a clouding of your eye’s lens and can occur in people who don’t have diabetes, though it may develop earlier in diabetics. Surgical treatment can clear up the lens or replace it with a human-made, plastic version.
Glaucoma is a serious medical condition that cause the build-up of fluid in your eyes. When this happens, you may experience intense pain and may be at risk of losing your eyesight. Some types of glaucoma are relatively symptom-free until they’ve progressed to a point where you may lose vision, making early detection very important. Glaucoma can be treated through medication and surgery: Many eye doctors routinely screen for it as part of eye exams, but you should ask just to make sure that your doctor is checking you for the condition.
Changes in blood sugar levels can cause blurred vision. This typically goes away once you’ve got your blood sugar under control, though it may take a few months for your eyesight to get back to normal. If you do notice that you’re having trouble seeing things, be sure to get your eyes checked. While the problem may be something as simple as astigmatism or presbyopia, blurred vision has more serious causes, including diabetes, so it’s important to get a medical evaluation.
There does appear to be a connection between good management of diabetes and the severity of the many conditions that often accompany it. While eating right and monitoring your blood sugar won’t absolutely prevent eye problems or other medical issues, they can help delay the onset of complications and minimize the severity of co-morbid conditions. If you have diabetes, it’s important that you talk to your doctor about any vision problems that you may be experiencing. It is also a good idea to get regular eye exams, which can identify eye problems in their earliest stages so that they can be treated effectively. Your eye doctor can put you on an exam schedule that meets your needs.
Wednesday, December, 4 2013 by Lainie Petersen
Forget that tired old question about who’s hotter, Ginger or Mary Ann.
In this corner, weighing 150 pounds (and that’s just his forearms), is everybody’s favorite sailorman. Look at him nuzzle his anorexic extra-virgin girlfriend and inhale his spinach right from the can.
In that corner, weighing oh, probably 20 pounds (and that’s just his ears), is Elmer Fudd’s favorite nemesis. Look at him nonchalantly lean on the ropes while he chomps on a fresh carrot.
So who’s it going to be? The perpetually squinting Bluto-battler or the Cwazy Wabbit? Amazingly, the winner by a knockout is Popeye!
Spinach before carrots? How can that be? Didn’t our moms tell us to eat our carrots because they’re good for our eyes?
Yes they did. But they also told us that if we keep crossing our eyes, one day they’re going to get stuck that way. We love our moms, but maybe they’re not the most reliable source of information when it comes to eyes.
Nope, the consensus is in from nutrition and vision experts: the nutrients in spinach are actually better for the health of your eyes than the ones in carrots.
Let’s look, with both eyes open, at some facts surrounding nutrition and vision.
These facts come courtesy of the Age-Related Eye Disease Study (AREDS) and its follow-up, AREDS-2, both conducted by the National Eye Institute (NEI), which is part of the United States’ National Institutes of Health (NIH).
Keep track of those acronyms. There will be a test later. Not.
Results from AREDS, begun in 1992, were published in 2001. Results from AREDS2, begun in 2006, were published this year. Each study examined the two most common forms of eye disease, age-related macular degeneration (AMD) and cataracts.
What are those, exactly? Let’s start with macular degeneration.
The macula is part of the eye’s retina, which serves a similar function to the film in a camera. We should probably explain that before there were digital cameras there was this thing called film. Google it.
Just like a camera lens, the eye’s lens receives an image. The image is transmitted to the retina, like the way an image taken by a camera lens used to be transmitted to the film in the camera.
The macula is in the center of the retina. When light comes to a point of focus on the center of the macula, you can see objects and colors sharply.
The macula is yellow, which enables it to absorb harmful blue and ultraviolet light that enters the eye, blocking this harmful light like a pair of sunglasses.
AMD comes two ways: dry and wet. Dry is when the tissue of the macula deteriorates. Wet is worse – that’s when the blood vessels behind the retina leak blood and other fluid into the macula.
AMD is the leading cause of blindness in the U.S. of people over 60, according to research conducted under the auspices of Johns Hopkins Medicine. Some estimates put the number of affected people as high as 15 million. However, many of those people are only mildly affected or won’t experience a decline in vision at all. But about 2 million Americans with AMD are severely affected, to the point of acute vision loss.
Check out this picture, which you can look at to test to see if you have any form of macular degeneration:
Click here for the full grid and explanation
Now let’s examine cataracts.
Cataracts form when the eye’s lens becomes cloudy, leading to blurred vision and vision loss. Cataracts happen because the lens of the eye is made up mostly of water and protein. As we age, the protein begins to clump together, creating the cloudy effect on the lens.
Most cataracts are related to aging and are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract-removal surgery, according to statistics compiled by the American Academy of Ophthalmology (AAO). In addition, almost 22 million Americans have cataracts in at least one eye, and the number is expected to increase to 30 million by 2020.
OK, so now that we know what AMD and cataracts are, let’s look at which nutrients AREDS and AREDS2 found helpful in addressing these eye diseases.
The first study, AREDS, examined whether taking vitamins E and C, zinc, and beta-carotene – which makes carrots orange – reduced the onset of these diseases.
For AREDS2, the NEI scientists added omega-3 fatty acids and the antioxidants lutein (pronounced LOO-teen) and zeaxanthin (zee-ah-ZAN-thin) – both of which are abundant in spinach, kale, and other leafy green vegetables. Both of these antioxidants are also present in the macula.
In addition to being antioxidants – which are molecules that help maintain the health of cells – lutein and zeaxanthin are carotenoids. Carotenoids are what give plant foods their colors.
Lutein is especially important because it gives the macula its yellow pigment. When this pigment degenerates – causes of this degeneration include aging, a poor diet, smoking, being a female, and having blue eyes – the macula degenerates, too, because the protection the pigment supplies gets lost. It’s like a dark, polarized sunglass lens getting replaced by a clear lens on a bright, sunny day.
Now let’s go back to the studies and their findings.
Contrary to the preliminary results of AREDS, the AREDS2 results show that taking vitamins E and C, beta-carotene, zinc, and the omega-3s had no effect on decreasing the onset or reducing the effects of either disease.
However, there were significant reductions in AMD from lutein and zeaxanthin.
Moreover, when beta-carotene was removed from the study, the scientists found that the AMD-reducing effects provided by lutein and zeaxanthin doubled.
Sorry, Mom. Sorry, Bugs.
AREDS2 also found that neither lutein nor zeaxanthin prevented cataracts from forming. But that’s not to say that there are not foods that help prevent cataracts. A 1993-2009 study conducted by researchers at the University of Oxford in England found that vegetarians and vegans were less likely than meat eaters to develop cataracts – vegetarians 30 percent less likely, vegans 40 percent– and that the more meat people ate, the greater the likelihood they would develop cataracts.
But let’s say you’re a young whippersnapper who hates carrots and spinach. You are years away from getting cataracts, and you spend more time thinking about getting MDMA than AMD.
We can hear you now:
“Dude. Why should I care about this? My vision’s 20/20. I’m sticking with the four major non-food groups – doughnuts, candy bars, 64-ounce sodas, and cigarettes!”
Go ahead, knock yourself out. But remember Dud, uh, Dude, what you eat now affects your eyes today and in the future.
Keep eating junk food and smoking cigarettes, and you could be setting yourself up for type 2 diabetes. Almost 400 million people around the world have diabetes, and 25 million of them are Americans, according to the American Diabetes Association (ADA). Close to half of all American diabetics have some form of diabetic retinopathy, which, after macular degeneration, is the second leading cause of blindness of people in the U.S. Also, people with diabetes get cataracts earlier, and diabetics are 60 percent likelier to get cataracts than non-diabetics, the ADA states.
Type 2 diabetes used to be known as adult-onset diabetes, but the number of children and adolescents who have this type of diabetes has greatly increased during the past 20 years. Consequently, the name of the disease has changed to reflect this appalling reality.
But if you eat a diet rich in – you know what’s coming – fruits and vegetables, that will not only improve your chances of maintaining good vision but improve your overall health, too.
And that’s what’s up, doc.
Eye Diagram Via: Wiki Media Commons
Monday, November, 25 2013 by Matthew Surrence
Science News reports that some researchers are looking into the possibility that a lack of outdoor play in childhood may contribute to nearsightedness (myopia) later in life.
According to the article, there’s been an increase in cases of nearsightedness in recent years: In the United States, 1/3 of the adult population suffers from the condition. But this is nothing compared to what is going on in East Asia:
“Recent studies of young men in Seoul and college students in Shanghai find that more than 95 percent are nearsighted. Increases also have shown up across other urban centers in the Far East.”
Some have speculated that technological changes, such as the proliferation of computers and video games, along with significant pressure in Asian cultures to succeed academically, have contributed to nearsightedness. Interestingly, while recent studies suggest that spending time outdoors is good for eyesight, some of them show no evidence that long hours studying or working on a computer compromise a eye health.
As for the connection between spending time outdoors and better eyesight, the connection hasn’t been fully established and scientists aren’t sure why outdoor time would affect eyesight. Some have suggested that spending time in natural sunlight or viewing distant objects may help prevent myopia in the future. However, it isn’t clear whether either activity is the key to preventing nearsightedness: There may be other factors that protect eyesight. It’s also possible that a mix of factors act to ensure normal eye development.
Of course, if you’re having difficulty seeing things at a distance, or suspect that your child is having trouble seeing far-away objects, it’s time to get an eye exam. Eyeglasses can help address visual difficulties. Meanwhile, get outside for a bit of sports, walking or just relaxing. Fresh air and sunshine are both good for the soul . . . and possibly for the eyes.
Wednesday, November, 6 2013 by Lainie Petersen
If your prescription (Rx) has a correction in the Cylinder (CYL) and AXIS sections, this means you have an astigmatism.
If you have an astigmatism correction on your Rx – and the vast majority of eyeglasses wearers do – you may be experiencing one or more of these symptoms when you are not wearing corrective lenses:
- Blurry vision
- Double vision
- Having to squint to see near and far
- Difficulty focusing on printed words
- Eye strain
- Tired eyes
What causes an astigmatism? It’s predominantly genetic, and it’s usually present to some degree at birth. It may increase or decrease with age. Someone may also develop an astigmatism following an injury to the eye, eye disease, or eye surgery.
An astigmatism results when one or both of the two parts of the eye that bring images into focus – the cornea and the lens – are aspheric. This means that they are not perfectly round and smooth spheres, like a ping pong ball.
An aspheric cornea or lens is more like the oblong shape of a football.
When the cornea and lens are round and smooth, they focus light directly onto the middle of the retina, at the back of the eye, making what you see look crisp and clear. In this case, your cornea and lens are perfectly spherical.
You don’t have an astigmatism if it says “SPH,” meaning “spherical,” on your Rx in the CYL section. Writing “SPH” in the CYL section is one of the ways an eye dr. indicates that the cornea and lens are perfectly round – spherical – and that no astigmatism is present. It’s not uncommon to have an astigmatism in one eye but not in the other.
Another abbreviation for “no astigmatism present” is DS, short for the Latin phrase diopter simplex, which means “unaffected,” indicating that this eye is unaffected by an astigmatism.
But let’s say you have an astigmatism correction on your Rx. If so, you will see a minus or plus number in the CYL section of your Rx.
If the CYL number is preceded by a minus, this means that the aspheric cornea or lens causes light to come to a focus point in front of the retina. It stops at a place that’s too near – not far enough to reach the retina – for you to see well. If the CYL number is preceded by a plus, this means that the aspheric cornea or lens causes light to come to a focus point behind the retina. It stops at a place that’s too far – not near enough to reach the retina – for you to see well.
Each type of astigmatism is corrected by the number in the CYL, which is literally a cylinder placed on your lens, which would be a convex (curved outward) cylinder if the Rx calls for a plus CYL, or a concave (curved inward) cylinder if the Rx calls for a minus CYL.
You will also see a whole number, somewhere between 1 and 180, in the AXIS section. If you have a plus or minus number for the CYL but nothing written in the AXIS field, call your eye dr.’s office. There must be an AXIS if there is a CYL.
Here’s why: the AXIS is literally the degree of angle at which the cylinder is placed on the lens.
For example: if the AXIS number is 180, the astigmatism is corrected by placing the cylinder horizontally on the lens. If the AXIS number is 90, the astigmatism is corrected by placing the cylinder vertically on the lens.
Sometimes the eye dr. will write the AXIS number with one or more zeros before the actual AXIS number, such as 005 or 090. Those preceding zeros are just placeholder digits and the actual AXIS number is 5 or 90. The preceding zeros won’t show up on the AXIS drop-down window on the Your Prescription page where you enter your Rx numbers. You can ignore those zeros.
Every Rx lens Zenni Optical offers can accommodate an astigmatism correction. A strong astigmatism correction would be one that has a number in the CYL category between 2.50 and 6.00, plus or minus on the Rx. The highest CYL number we can correct is plus or minus 6.00, and most of the lenses we offer can accommodate this CYL correction.
Because correcting a strong astigmatism is more complicated than correcting a mild astigmatism, an extra-strength charge is assessed on orders of glasses with single-vision lenses when the Rx indicates a strong astigmatism. Bifocal or progressive lenses with high CYL numbers that call for strong astigmatism corrections come with no extra-strength charge.
Tuesday, November, 5 2013 by Ryan