One of the most important measurements for your eyeglasses is your pupillary distance (or PD). This number is very challenging to get yourself, and ideally you need experience to measure it, so most are better off getting it from their optometrist. If you spend time surfing the cheap eye glasses websites you will discover that they all need this measurement to properly make your lenses. This will be the easiest thing on your prescription to mess up, so be sure it’s correct.

Many of you may end up selecting the wrong style frame for your face and all because the eye glasses are so cheap. I really took a chance with one pair of mine because I wanted to try something outside the box. At the absolute worst, I was out the $25 I spent on that pair (see, cheap eye glasses) and had a spare set to stick in the back of the drawer. Just make sure that the frame you chose will physically fit your face (all the shops have full measurements available), and have fun picking out your new style.

Choosing frames that are too large may mean that your new glasses will fall of your nose. If they are too small, you’ll feel uncomfortable, as they may pinch the bridge of your nose. Either way, if they aren’t the right size for you, you’ll end up owning a useless pair of discount eyeglasses. When choosing my cheap glasses, I started with the measurements of my old frames to give myself a baseline. Several of the online shops even have rulers you can print if you don’t have one of your own.

If you check all of your options, you will see that getting glasses online isn’t as scary as you thought. Follow the steps we’ve outlined above (remember pupillary distance) it will all turn out fine. There is nothing better than choosing outside the box when getting your new cheap eyeglasses and getting that first compliment when wearing them out. You can even mix and match them to go with your current wardrobe. This is the power that buying cheap eye glasses online gives you.

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Anyone who has undergone a physical examination at a doctor’s office or a comprehensive eye exam at an eye clinic has seen what is called a “Snellen chart.” This is the chart hanging on the doctor’s wall with the large “E” printed at the top. This chart has been used since the late 1800’s to measure an individual’s visual acuity. Many modern eye clinics and family physicians use an electronic “viewfinder” version of the Snellen chart, but the ratios and results are the same.

Standing 20 feet from the chart, you are asked to cover one eye and read the characters on the chart. If you have 20/20 vision, then you are able to accurately read from 20 feet what someone with normal vision can read from 20 feet. Someone with 20/40 vision is able to see at 20 feet what someone with normal vision would be able to see at 40 feet, and so on.

This visual test only measures visual acuity and cannot sufficiently account for the quality of a person’s vision. Other tests are necessary to determine an individual’s ability to see color and contrast, for example. In other words, 20/20 vision is only one component of normal vision.

A comprehensive eye examination by a certified ophthalmologist or optometrist will measure both the acuity and quality of your vision, as well as help determine whether you have other eye conditions.

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If you wear corrective lenses you are effectively decreasingly the amount exercise your eyes have to do, this results in a deterioration in your focusing skills. So when you couple strained eye muscles with poor focusing you can see (or maybe you can’t!) how your eyesight continually worsens until you need stronger corrective lenses, and this process just keeps repeating.

Most opticians will keep this a secret but there are actually a number of exercises you can do to reduce strain and tension in your eyes. If you take just five minutes a day to do these eye exercises then you will find that your eyesight will slowly improve, and it could save you another expensive trip to the opticians!

Look Out The Window

This is a simple name for a simple exercise and it’s particularly effective for those who spend a lot of time indoors or working at a computer. All you have to do is look out of the window every now and again for a minute or so. The natural light will relax your eye muscles, especially after the strain caused by a computer monitor.

Palm Cupping

First rub the palms of your hands together to warm them up. Close your eyes and gently cup your palms around them. You will be able to feel your eyes relax during this exercise. Use this technique for ten to thirty seconds at a time.

Fixed Eye Movement

Whilst sitting or lying down look up as far as you can and hold for five seconds. Allow your eyes to centre again for a couple of seconds before looking down for five seconds. After those five seconds, again allow your eyes to centre. Repeat this process, looking both to the left and to the right.

Full Body Relaxation

Stand with your feet slightly apart, and with your knees bent a little. Slowly rotate your body at the hips from side to side while allowing your arms to move in a relaxed manner. Keep your eyes open and focus as the world gently spins around your gaze. This exercise is also very good for your lower back so if you’re someone who spends a lot of time sat at a computer then this is a “must-do”!

As well as the above exercises there are a few easy ways to cut down on eye strain everyday. Move your seating a metre or so back from your television, spend less time on the computer, get seven hours sleep a night and only wear corrective lenses when absolutely necessary.

Keep doing your eye exercises everyday and soon it’ll all become clear!

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Before I can answer how LASIK and other laser eye correction procedures work, it is important to understand that laser eye correction is used to primarily treat vision impairments such as nearsightedness, farsightedness and astigmatism.

During an initial consultation with your eye surgeon, your eyes will be tested for their suitability and compatibility for laser eye correction. Patients who suffer from certain conditions such as dry eyes, glaucoma, diabetes and cataracts may be advised against going for the surgery.

Now, we come to the main question which is How does laser eye correction work? How does LASIK work? Basically, there are a few phases involved, as we will be showing you below:

Phase One: Patients will be placed in a reclining chair and anesthetic drops will be placed into the eyes to numb them. Once the drops have taken effect, the surface of the eye will be cleaned. The eyelids will be kept open using an instrument that is known as the speculum, this will prevent you blinking. Suction will then be used around the cornea area. This will cause blurring and dimming of the vision, and while it may be a little uncomfortable and unnerving there will be no pain. The last step of this phase involves the surgeon cutting a thin, circular flap in the surface of the eye, to gain access to the cornea, with a surgical knife known as the microkeratome.

Phase Two: The patient’s corneal tissue is cut and reshaped using a preprogrammed laser. After the required reshaping, the corneal flap will be replaced. A preventative shield may also be used to protect the eyes from irritants.

The actual operation will normally last only a few minutes, as only one eye will be treated at a time. Patients will start to experience improved vision in 24 hours. It is important for laser eye patients to take necessary postoperative eye care steps for a smooth and effective recovery process. Visit your eye surgeon on a regular basis or as needed.

Laser eye correction is a once-in-a-lifetime event for most people. There are many preoperative as well as postoperative do’s and don’ts to be adhered to. Follow the eye surgeon’s advice for more effective laser eye correction recovery. When in doubt, consult your regular eye surgeon. I hope I have helped to shed some light on the question of how laser eye correction works.

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The actual surgery only takes minutes to perform. What differs for most patients is the postoperative recovery period. For some, it can take a few days, while for others it can be up to a few months.

After laser eye correction, some patients’ will be told to use a protective shield to cover the eyes, depending on the type of procedure performed. This protective shield should be used for as long as your eye surgeon recommends. Eye surgeons will also advise patients to use antibiotics, moistening eye-drops or even anti-inflammatory drops. Patients may also be asked to wear sunglasses if they develop sensitivity towards sunlight. For a lot of people, laser eye surgery is not a setback to their lives. They return to their normal activities and even work within a few days after surgery.

There are very rarely any postoperative complications. Patients usually have to attend at least one follow-up exam, which will be arranged by the surgeon during the recovery period to ensure proper and complete healing of the eyes. Some surgeons will also advise their patients to go to sleep as soon as they can after surgery to minimize the risk of postoperative pain occurring. Patients tend to feel a significant vision improvement after waking up from their sleep.

Nearsighted patients will usually experience normal vision returning the day after surgery. If any difficulty reading is experience, it is considered to be a normal side effect of the procedure. For farsighted patients, they will also normally experience a drastic improvement in their vision the day after surgery. If distant objects seem blurry, for them, it is also considered to be temporary and normal.

Postoperative patients should lie down, close their eyes and relax as much as possible. Activities that could strain the eyes, such as reading, watching television or using the computer should be avoided in the first 24 hours after surgery. Another thing to remember is to wear a protective shield, like an eye mask, for the first 7 nights after surgery to prevent the eyes being rubbed during sleep. Patients are allowed to take showers, but avoid getting the shower spray and soap directly into the eyes. It is also advisable to avoid using make-up, consuming alcohol or be in smoky and dusty environments for 48 hours after the surgery.

Patients who follow these tips should have a smooth and easy post laser eye correction recovery process.

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The strength of prescription eyeglasses is measured in dioptres. A normal prescription will contain spherical dioptre values, cylindrical dioptre values, Axis Value and any addition values. Some commonly used abbreviations in an eyeglass prescription are: DV = D.V. is an abbreviation for “distance vision”. This specifies the part of the prescription designed primarily to improve far vision. NV = N.V. is an abbreviation for “near vision”. This may represent a single-vision lens prescription to improve near work, or the reading portion of a bifocal lens. O .D. is an abbreviation for oculus dexter, Latin for “right eye.” And O.S. is an abbreviation for oculus sinister, Latin for “left eye”. (Some eyeglass prescriptions simply say “left” and “right” instead of “O.S.” and “O.D.”)

The lenses of Prescription eyeglasses are manufactured from diversity of materials. Glass lenses (which was once upon a time the most commonly used material), it comes in several diverse colours and has very good scratch resistant properties. Also, it is the least expensive. Disadvantages of a glass lenses are (a) its heavy weight; (b) It is fragile. Another material that is used to produce prescription eyeglasses is high-Index artificial lens. It absorbs ultra violet rays very well. This kind of lens is much lighter in the weight than glass lens but at the same time it can also be scratched very easily. Resin Plastic is one more kind of the material used in manufacturing prescription eye lenses. These are the lightest of all the lenses and are very fast replacing the use of glass lenses. These lenses don’t offer high level of defence against the ultra violet light, but there are a variety of coatings available in the market which overcomes this shortcoming of these lenses.
A wide variety of coatings can be applied to prescription lenses. An Ultra Violet coat protects the eyes from harmful UVA and UVB rays. A scratch resistant coating to the prescription eyeglasses reduces the chances of scratches on the lens due to normal day to day handling. The most recent type of coating is the anti-reflective coating. It reduces mirror images as it allows light to pass through the lens.

People also get their prescription eyeglasses tinted with a wide variety of colours. Tints increase comfort in bright light situations, reduce glare from computer screens or fluorescent light, and make a fashion statement as well.

Today, not only are prescription eyeglasses a necessity, but to some people they are a fashion accessory as well. Top designers like Giorgio Armani, Eddie Bauer, Calvin Klein have picked up this latest fashion trend and have started designing their own collection of frames for prescription eyeglasses.

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Los Angeles LASIK eye surgeon Dr. Andrew Caster, for example, who was named one of the “Best Doctors in America” in 2005, 2006, 2007, and 2008, graduated from Harvard Medical School and then was Resident in Ophthalmology at the UCLA Jules Stein Eye Institute from 1981-1984, and was the Clinical Instructor in Ophthalmology at the highly prestigious UCLA School of Medicine. Andrew Caster MD also wrote a book called Lasik: the Eye Laser Miracle, which has become one of the most widely read books in the U.S. on the subject of laser vision correction.

Perhaps some of these credentials, and many more worth mentioning, that some of the highest paid athletes and celebrities in Los Angles have turned to Dr. Andrew Caster for their laser vision correction procedures. Los Angeles Lakers coach and former player Kurt Rambis, NBA athlete Rick Fox, professional golfer Amy Alcott, Fox Television’s “The Swan,” and most recently E! Network talk show host and comedian Chelsea Handler, have all gone to Dr. Caster of Caster Vision in Beverly Hills, for LASIK eye surgery and have had much to say about the astounding results. Although LASIK is not for everyone, it has helped millions of people worldwide rid themselves of glasses and contact lenses, and enjoy perfect 20/20 vision. Results are typically successful in this way, and the procedure has gained so much popularity amongst Angelinos in the few years. However, only your doctor can tell you if you are a good candidate for LASIK, based on the details of your individual eyes. To learn more about LASIK and Dr. Andrew Caster of Caster Vision, visit www.castervision.com.

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Wavefront LASIK (also called Custom LASIK), and traditional LASIK both:

· Use an excimer laser

· Create a tiny flap on the corneal surface to expose the underlying tissue to be worked on

· Modify the shape of the cornea by vaporizing tiny pieces that were impairing your vision

· Are extremely precise

Advantages of Wavefront (Custom) LASIK

It provides particularly precise information on how your vision is impaired. Custom LASIK measures each eye with a special laser, using wavefront technology, and creates a 3-D map of the eye. This is translated by the Wavefront system into mathematical information that’s used to guide the laser in correcting the problems.

Two types of vision problems

· Lower order aberrations – nearsightedness, farsightedness and astigmatism.

· These are refractive errors and are correctable by traditional LASIK surgery.

· Higher order aberrations (HOA) – halos around lights, impaired night vision, starbursts etc.

· These are not refractive errors and not correctable by traditional LASIK, but can be measured and corrected by Wavefront LASIK.

The HOAs are sometimes created by traditional LASIK, and although there are still some who argue that Wavefront LASIK can also create them, most refractive surgeons agree that it’s much less likely to create them than traditional LASIK.

· About 75% of refractive surgeons now use Custom LASIK.

· Amount vs. quality of vision

Amount – A person with 20/20 vision is said to have perfect eyesight. That’s an

assessment of the person’s AMOUNT of vision, or how MUCH he sees. Impairment of our amount of vision is brought about by lower order aberrations.

Quality – How WELL we see is determined by the presence or absense of higher order aberrations. So if we have impaired contrast sensitivity and can’t see very well at night, or we have glare and halos around lights, these defects can be both measured and treated by Wavefront LASIK.

The Wavefront LASIK procedure

· The eye surgeon sends a light ray into your eye

· The light is reflected back off the retina (interior surface of the back of the eye, like the film in a camera) to the Wavefront system

· The system arranges this modified light into a pattern of all your vision aberrations, lower and higher

· It displays this pattern on its computer monitor as a 3-D map of each eye, the wavefront map

· When your eye surgeon applies the laser treatment to your eyes, he uses this same information to guide the laser.

Unique to you

This all results in a vision remedy that’s unique to you. Unlike glasses and contact lenses, which are remedies that come according to prescriptions that millions of other people also have, this treatment is entirely customized. That’s another way of saying that it’s extremely precise, so precise that nobody else would benefit from it. They’d all have their own 3-D maps.

Pre-testing with traditional LASIK

Before traditional LASIK, there are also tests done to pinpoint the corneal problems.

They’re done using a variety of devices which each give a different kind of information. For example:

· The photopter – you look through various pairs of lenses and tell the eye doctor which set gives you the best clarity

· The corneal topographer – collects reflected infra-red light from your eyes and creates a digital map of each eye

· Fluoracaine or some similar dye – stains the corneal surface so that your eye doctor can see more clearly where the irregularities are

These tests give a lot of information, but not to the precise detail of the wavefront technology. They also take longer.

Wavefront diagnostic

If you’re considering a LASIK procedure, whether LASEK, PRK, or Epi-Lasik, or traditional LASIK, you can have a wavefront diagnostic done first. This will indicate the severity of any HOAs you may have. This information in turn will guide your eye surgeon in recommending the best procedure for you.

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But not everyone is a good candidate for LASIK. A patient needs to go through a comprehensive eye exam by an ophthalmologist or eye surgeon to determine if their eyes will benefit from this procedure.

LASIK Requirements

For safe laser eye surgery, an ophthalmologist looks for certain criteria to reduce any risk factors associated with LASIK. The patient must meet the following guidelines:

· To be sure that the eye has developed properly and matured vision must be at least 18 years old.

· The patient has had no eye injury or infection within the past year.

· The candidate does not have any autoimmune disorder such as Lupus or Sjorgren’s Syndrome.

· No history of herpes infections in the eyes.

· The cornea has no scars

· The patient cannot be pregnant or nursing

· Individuals with dry eye syndrome are not good LASIK candidates.

· Individuals with pupils that dilate beyond seven millimeters in the dark are not good candidates for LASIK.

Eye Characteristics

Other general requisites for LASIK include various characteristics of the eyes. LASIK is not a good option if patient’s eyes have the following attributes:

· Corneas are steep

· Corneas are flat or thin

· Corneas are irregular in shape

· Pupils are too large

LASIK Alternatives

There are other options for patients who aren’t a good fit for LASIK. Wavefront-guided custom LASIK is a form of custom LASIK that measures, and maps an individual’s specific eye irregularities 25 times more precisely than standard methods.

Another promising alternative is Implantable Contact Lens surgery (ICLs). ICLs are surgically placed behind the iris and act just like contact lens. One of the greatest advantages of ICLs is that they’re not permanent and can be reversed. If the results aren’t perfect, the ICL can be removed or replaced. ICLs are perfect for people who can’t undergo LASIK treatment because of thin corneas, dry eyes, or large pupils.

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The following three IOLs are used to replace lenses damaged by cataracts and presbyopia (middle-aged vision).

Crystalens®

This procedure takes 15-45 minute per eye and is done with local anesthetic. It is ideal if you require good night vision, and don’t mind the possibility of having to wear reading glasses despite your IOL. You can usually resume your normal activities the day after surgery. Distance recovery is immediate, but you should allow weeks for computer and reading distance to recover fully.

Benefits

· Stable, long term outcomes

· Best clarity of vision

· Eye focus is similar to natural focus

· Good distance vision, computer vision, and night vision

Limitations

Crystalens is a more difficult procedure and can have poor improvement for reading-range vision. It can also take your eyes up to a year to fully adapt.

ReSTOR®

This procedure takes several hours to complete both eye. It requires local anesthesia, and you can return to your normal activities the next day. However, most surgeons advise taking one or two days off work. You can immediately enjoy improved general, computer and reading distance vision.

Benefits

· Near and far focusing is improved so greatly, that you may no longer need glasses or contacts again

· Ideal for reading small print and seeing objects close up

· Good distance vision

Limitations

ReSTOR can have poor results for improvement in computer distance and night vision. Clarity is also not as crisp as with other IOLs. You may still need glasses to read small print.

ReZoom™

This procedure takes about 15 to 45 minutes for each eye and uses local anesthetic. There is a wait of three to eight days before the second eye is corrected. ReZoom also enables you to resume your normal activities the day following surgery. Complete vision recovery takes anywhere from one to two weeks, while your eyes adjust to their new lenses. ReZoom creates multiple focal points, so distance is improved at all distances.

Benefits

· Immediate improvements to general, computer and reading distance vision

· Best independence from glasses and contact lenses compared to other IOLs

· Good overall vision quality

Limitations

ReZoom may make only moderate improvements to computer distance vision. Reading range vision is improved, but only moderately. Night vision and clarity can be poor. You may also experience temporary halos or glare, and still need glasses to read fine print.

Am I a good candidate?

If you are in overall good health and are suffering from cataracts or presbyopia, you may be a good candidate for lens implant surgery.

If you have chronic infections, uncontrolled diabetes, or any other type of health problems, you may possibly still have this surgery—but your condition must be under control first.

If you have had previous refractive surgery such as LASIK, you may be a candidate for IOL surgery, providing your eyes are now in good health. Your initial examination and consultation will determine your candidacy for these procedures.

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