A Word about Frame Adjustment and Maintenance

I know I announced my brief hiatus, but I wanted to talk a little bit about frame adjustment and its importance to the wearer.

If your eyeglasses are not fitting properly on your face, not only are they uncomfortable, but it also adversely affects the quality of your vision through a variety of ways.

Examples

Daniel_Sharman_by_Gage_Skidmore_2

If you have any astigmatism correction, and your glasses are crooked, then you are getting the incorrect prescription. As discussed in my previous article on correction found here, astigmastism correction is set on a specific axis. If the glasses are crooked you have changed the angle of that astigmatism correction on each eye, negatively impacting the clarity of your vision.

Glasses are made to sit on your face at a certain distance from the eye. If that distance is elongated, you are changing the magnitude of the correction. So, as glasses slide down your nose, you actually make your lenses less nearsighted, or more farsighted. Whatever your real correction is, this is something you want to avoid.

Glasses need to have a certain amount of tilt towards your cheeks. This provides the best clarity. If your glasses end up too tilted towards the cheeks, or not enough, then you reduce your clarity again.

Progressives compound all of these issues. If a progressive is worn crooked, then you end up with one eye looking through the distance, while the other looks through the intermediate. AND your astigmatism correction is also wrong at the same time!

Take Away

So what’s the lesson here? You take your car in for a tune up and oil change every 5-10,000 miles, why don’t you take your glasses in for a tune up too? A good rule of thumb is every 3 months or so. The frequency may vary based on your local weather. Hotter climates tend to mean frames will stretch out and get crooked faster. Going in frequently also means that your optican can tighten all screws, give the frames an ultrasonic bath to remove makeup and sweat build-up, and your glasses can be inspected for scratches or warranty issues.

Your optician is your friend. Visit him or her frequently!

Advertisements

Very Brief Hiatus for the #JediLine

As most of you know I am intimately involved with LiningUp.net and the Star Wars lines we produce at the TCL Chinese Theatre IMAX in Hollywood California.  As our line for The Last Jedi starts in just one week, I will be tied up with many responsibilities to help this charity event take place and will be putting this blog on a very brief hiatus.  I will be back up with new posts after December 16th. You can follow my exploits as member of the Social Media Team on Twitter and Facebook. And if you would care to support our endeavors to raise money for Starlight Children’s Foundation, you can donate here! Since 1999 we have raised over $100,000 for this excellent charity.

In the meantime, I will continue to respond to any messages or emails you may have for me.  May The Force Be With You

Review Update on Varilux X Design

I posted an initial review of the latest progressive lens from Varilux, the X Design, when it first launched back in late August/early September.  My initial review can be found here.  After wearing the lenses for a couple of months, I wanted to provide an update based on my continued observations.

Review of Varilux X Design…Continued

As you may recall, my initial review of the latest progressive lens from Varilux, the X Design, was glowing.  My experience of the near and intermediate zones was phenomenal.  After wearing continuously for over two months, I still find this to be true, but I do wish to get a little more detailed on the experience.

varillux-x-series-logo

Breaking down the Distance

I believe I have found how they improved the intermediate and near so much.  The width of the distance zone is noticeably smaller.  While it’s not so small I would call it problematic, I think it’s important to note that if your needs are exceptional crispness and width of field in the distance, you may want to pause before going with the Varilux X series.

My initial thought when I noticed the smaller distance zone, was that perhaps my glasses weren’t properly aligned.  I suspected that my pupils might be sitting on the edge of the intermediate zone and that was why I was having issues.  But I remarked my lenses and took note of placement…even making small adjustments to how they sat on my face…and I could not increase the width of my distance vision.

The vast majority of my visual lifestyle takes place in the intermediate and near zones.  All of my work with patients, on computers, and phone/reading.  However, I am also exceptionally picky about my distance vision and I am a dominant eye-turner.  Rather than holding my eyes straight ahead and move my neck to align my vision, I tend to look out of the corner of my eye and expect to see sharply.

IMG_3530

Note the black dots on lenses to note corridor position

This has led me to rethink my initial glowing review of the X series.

Intermediate – Arms Length

XDesignDifference

The zone of the lens dedicated to arms length (think your computer monitor, or dashboard in your car) is excellent.  Both the width of this zone, as well as the depth of field is very good.  The depth in the corners of this zone is not quite as good as the center.  So, if you need to see something closer than you’d expect at that height, it needs to be in the center of the zone, and not out of the corner of the eye.  Still enough quality width, clarity, and depth to highly recommend if this distance is critical for you.

I have noted that patient experiences have varied a bit on the quality of this zone, based upon how tall their lens is (how much distance from their pupil to the bottom of the frame).  Those with a longer corridor, or a stronger add (over +2.25) seem to find their intermediate zone a little lower.  This can still be fixed with adjustment of fit to a great degree, but it is something to consider if the frame you choose has your eyes very close to the top of the lens and it’s oversized.

Near Zone – How’s the Reading?

PALChannel

The reading-or near zone, has a similar wearing experience as the intermediate.  The width of the zone is very very good.  If you want to see something at arms’ length, then you’ll want it closer to the middle of your lens.  But there are a couple of spots in the periphery where the intermediate distance becomes quite good.  You do have to hunt for this location just a bit.  When it pops in for intermediate it’s very very good though.

Does it Work for All Prescriptions?

So far, after fitting this as my primary progressive lens for over two months, I have found that there seems to be a broad range of prescriptions which can wear this lens design effectively.  So much so that I would not say there is any specific power limitations for a good wearing experience.

Take Away

I still feel that the X Design lens is an excellent choice for the vast majority of patients.  I still love wearing the lens.  There is a peripheral loss of clarity in the distance portion of the lens, but it’s still far enough to the corners of the lens that I don’t find it exceptionally annoying or distracting.  If you need to have super crisp edge to edge distance vision, this lens design may not be for you.

While every lens design that comes out claims to be the salvation that fixes all the problems for all patients, this has yet to be true.  The X series comes very very close to doing this, but it’s still not quite the magic pill.

*please note that I have been wearing and testing the Varilux X Design.  The X series refers to a collection of 3 related lens designs, the X Design, the X Fit, and the X Fit 4D.  I have not tried the other two lenses in the family of products.

Lens Materials Advantages and Disadvantages

First things first, I would like to apologize for my extended absence.  Halloween season with a 9 year old means lots of time spent on costumes and parties.  Pair that with a small round of being sick and, well, here we are a few weeks later.

Today I’d like to spend a little time discussing the many materials that can be used to make prescription lenses.  There are many solutions to fit the many needs of different prescriptions and lifestyles.  There is no, one single best choice.  But I will break down the advantages and disadvantages on each material to help you navigate the best choice for your needs.

Abbe Value

No, Abbe isn’t a girl who works at the lab.  This is a number used to define how much aberration (distortion and/or color separation) occurs in a lens material.  The lower the number, the more distortion there is inherent in the material.

 

AbbeValues1

AbbeValues2

Now, I know these numbers by themselves won’t mean much to you.  But the essence of these numbers is that glass has the best optical quality available.  The trade off, however, is that glass is also excessively heavy (especially for a higher prescription), and it’s less safe as a rule given the brittle nature of the material.

Herein lies the rub.  The best optics almost always come with a trade off on weight and durability.  The lighter and thinner materials are more comfortable and cosmetically look better for higher prescriptions, but that does come with an optical clarity trade-off.

Index of Refraction

Refraction is the term used to describe how much light is bent when it enters a medium.  When we are talking about glasses, we’re always talking about the lens material.

Refraction_at_interface.svg

The a 1.0 index of refraction would indicate that the light is not bent at all.  Any number of 1.0 is indicating that the light is entering a different material which bends the light more dramatically.  The higher the number, the more the light is bent, and therefore the less material needed to correct for a high prescription.  Thus a 1.74 hi index plastic bends the light more than a 1.50 standard plastic (CR39).

The more the light is bent, the thinner and generally lighter the lens material is, but that extreme bending also means some light is lost to the prism effect (color aberration).  That is to say, lower abbe values separate white light out into its separate color components and you may actually see a small rainbow effect around the edges of things.

2000px-Chromatic_aberration.svg Chromatic_aberration_with_detail

This aberration is why it’s so important to take the additional measurements of not just pupil horizontal position, but also vertical position on a patient with a higher prescription.  These chromatic  aberrations can become very intrusive with hi index materials.

 The Polycarbonate Reputation

Polycarbonate has traditionally had a very bad reputation.  In part this is the same old story as Transitions.  The older versions of the material from 30 years ago were quite inferior.  Lots of aberration, chromatic distortions and very small optical centers.  In part it was the manufacturing process used at the time.  Over the past couple of decades the manufacturing of this material has improved dramatically.  You can still get “bad batch” versions with terrible distortion, but they are relatively few and far between.  I think it does say something to the improvement of the material that I wear polycarbonate almost exclusively in my glasses, and have for the past 10 years. It can be a good choice as long as your prescription isn’t too strong.

Choosing the Material for You

As you can probably guess from all the above material, the general rule of thumb is to go with the highest abbe value (meaning the least amount of aberration).  But this has to be balanced against the power of the prescription, and the impact resistance necessary for lifestyle.

For these reasons, polycarbonate (for better or worse) has become the most common lens material in the optical industry…at least in the USA.  While it does not have the best abbe value, it does have impact resistance.  It has a relatively wide range of prescriptions which can be corrected before chromatic aberration becomes an issue, and it is has a plentiful number of lens design solutions available (Transitions, progressive designs, glare treatments, etc.).  Is it the best solution?  I’d say probably not.  Is it the easiest solution?  It’s the safest bet of protecting the eye and giving decent visual acuity, while still having access to all the different ways of correcting vision needs.

All things being equal, I think I’d prefer to work with Trivex for most moderate corrections, but the limitations on progressive designs and transitions colors available keeps me from going to it frequently myself.  In fact, I wear polycarbonate for my lenses.

However, if your prescription is either above a +3.00 or a -4.00 I generally recommend considering high index to control some of the chromatic aberration and to provide a cosmetically thinner lens.

Take Away

There are many lens materials available, and finding which one best suits your needs comes down to how strong your prescription is, and how shatter resistant do you need your lenses to be…but in the end polycarbonate is often used just because of accessibility and safety, even if it isn’t always the best optical choice it’s still a decent choice for most common prescriptions.

Questions on Light Sensitivity

A friend recently sent me a Facebook Messenger question, and allowed for me to share it.  Here is our conversation on light sensitivity…

A.L.:  Hey Ric I have a professional question for you. I seem to be very sensitive to bright lights especially flashing ones. I can’t handle strobe lights or white fireworks. I also need to have sunglasses when I’m outside when it’s bright. I know a lot of people want sunglasses but I feel like I really need them. And I know other people don’t seem to have the issues with strobes and fireworks that I do. I’m wondering if there’s anything that I can actually do about this or if I just need to continue living with it and dealing with it. I thought you might have some insight.
And to be clear when I say I can’t handle strobe lights or fireworks I mean they cause me actual physical pain.

O.J.:  You’re not the first one I heard about having this issue. There isn’t a way to make it go away necessarily

You will want to spend the money on good sunglasses.
A.L.:  That’s kind of what I figured. [SPOUSE] had to lead me through some parts of the mazes with my eyes closed because of the strobes.
O.J.:  Night stuff is harder to deal with. Perhaps using a blue blocker lens for those situations.  Something like an Eyezen with a good Anti-Reflective, which filters just a specific band of blue light without altering the colors you perceive too much.  If that doesn’t work using a lens with more of a yellow filter like Prevencia or GUNNAR lenses might help. Though a Gunnar solution will change your color perception quite a bit.

I highly recommend Maui Jim for sunglasses. You can’t find better
A.L:  Cool. I never really knew which brands were expensive for the sake of being expensive and which were actually quality.
O.J.:  Maui does not have sales or discounts other than discontinued models at Costco.
A.L.: OK
O.J.:  Their lens tech is patented and better than any other. Probably suggest either the true grey or HCL lens color.
A.L.:  Thank you! I’ll look into those.

Anti-Reflective Coating is much more than you think!

Through a couple of recent conversations with blog readers and patients, it’s become clear that many do not fully appreciate just how complicated anti-reflective treatments are to manufacture.  I hope to dispel some of this misconception today…

More than a Dip!

Since so much of lens treatments can be cone by dipping a lens in a hot vat of some near-boiling liquid, it’s easy to understand how you might think that’s all there is to an anti-reflective coating.  But, believe it or not, even the most inexpensive (read: easily scratched) coatings require a multi-stage process to apply to a lens.

This video showing the application of Crizal Avance will give you a little window into the process of applying a no glare treatment to lenses.

Lenses need to enter a dust free room similar to those in the manufacture of microprocessors. Then they must go through a multi-stage bath system to remove any and all dust, residue, oils, or items with the potential of producing blemishes on the lens. Once the lenses are fully cleaned, then they are placed in a tray inside a vacuum chamber and blasted with various ionic elements so that they can adhere fully to the lens, and provide both the light bending action to minimize reflection, as well as provide the scratch, oil, and water resistance layers.  For the best coatings this is 9-15 layers to complete this process.

AR Chamber.png

Inside Chamber.png

Once the lenses are removed from the chamber, then they are given a visual inspection to make sure the coating adhered properly.  Any speck of dust left on the lens before entering the chamber will ruin the coating, creating a drip point from which the coating cannot adhere properly.

AR Layers

The Number of Layers in a Crizal Alize Coating

 

Take Away

There are many dozen variations on anti-reflective manufacturing, but all of them, even the most inexpensive simple solution, requires an elaborate process of cleaning, dust-free rooms, and vacuum chambers to apply the coating.  In great part, this helps to explain just why anti-reflective coatings cost so much.

 

Like what you see here?  Follow my blog, Facebook Page, and Twitter for the latest updates, and please leave comments below!

The Importance of Retinal Imaging

Over the past 15 years, the use of retinal imaging has become more and more prevalent in the modern optometric practice.  Unfortunately, most vision insurance plans don’t cover it.  So, it’s almost always an additional expense.  For this reason, sadly, many patients opt out of receiving this additional procedure.

The additional procedure of retinal imaging (and it’s associated cost) are not a way for the eye doctor to pad your bill, however.  It’s actually an incredibly useful tool for eyecare professionals to not only diagnose additional vision issues, but also greater health concerns.

Why Are Retinal Images Important?

Doctors need to take a look at your retina during your exam.  This is important for spotting issues which could adversely affect your vision.  But possibly even more important, the retinal exam allows the doctor to spot overall health issues.  The smallest visible blood vessels in the entire body are located in your retina.  Because so many of our health issues present themselves in blood flow, this allows your eye doctor to spot health problems such as diabetes and high blood pressure before even your primary care doctor can spot them.

150408-F-TJ158-064.JPG

Anecdotally, I even once treated a patient who had his physical the same week as his eye exam.  The physical presented that he had a clean bill of health and no concerns.  Our retinal exam spotted a blood clot…a stroke waiting to happen.

Daytona-Projected-Arteriolosclerosis.jpg

Example of Arteriosclerosis in digital retinal image

So Why Digital Imaging?

Before the advent of modern digital imaging, doctors had to dilate your eyes, and view your retina while wearing the BIO (Binary Indirect Ophthalmoscopy).  The doctor would view your retina using a magnifying lens and a head lamp.  This would allow the doctor view the retina in very high detail, but viewing very small segments at a time.

_mg_7953-2.jpgOptos Logo No Tag Light Eye Transparent.jpg

The advent of more and more advanced digital imaging, such as optos, now allow for the retinal exam to happen without dilation being necessary.  Not only this, but the digital retinal imaging allows us to capture the entire retina in a single image.  By capturing the entire map, there’s no question of anything being missed while sweeping across the retina with a smaller view.

Color-Healthy-California.jpg

Healthy Retina captured on optos

One of the most valuable aspects of a digital retinal image is overlay.  When you have the image taken over subsequent years, each image can be digitally dropped on top of the original image, and any minute changes can be compared and documented.  Some of the most concerning aspects of retinal damage can most easily be spotted when comparing images from year to year.  When you opt for a dilated exam, instead of the digital image, we cannot overlay images because all the doctor gets to see is the retinal with their own eye and cannot document it with a photograph.

Digital Image Critical for Diabetics

For a diabetic, it is absolutely critical to get the digital retinal image every year.  I am diabetic myself, and even though I’m only in my mid-40’s my most recent optos image found the beginning stages of diabetic retinopathy.  This particular eye condition has an end result of partial blindness and can be minimized by better maintenance of blood sugar levels.

California-DR-Stanga-1DiabeticRetinopathy5

Diabetic Retinopathy (red dots)

This is a great example of an eye condition which can be managed and observed best by comparing images from one year to the next.  This allows your eye doctor to track any small changes in the growth of the retinopathy, and recommend treatment based on the advancement.

You’ve also seen me talk about the dangers of Harmful Blue Light and it’s relationship to developing Age Related Macular Degeneration (AMD).  This is another eye condition most easily diagnosed and treated with the comparison of digital images from year to year.

Take Away

There is tremendous value for the eyecare professional, as well as for you, the patient, in getting the digital retinal images at your routine annual eye exam.  It’s not an upcharge to grift more money out of you.  This is an invaluable tool which allows your doctor to diagnose and treat not just vision related concerns such as detached retinas, but also overall health concerns such as diabetes, hypertension, and even blood clots!  It’s a very small price to pay for the peace of mind which could prevent much great vision and health concerns later on.

Thank you to optos for providing imagery in this post

Like what you see here?  Follow my blog, Facebook Page, and Twitter for the lastest updates, and please leave comments below!

The Dangers of Mishandled Contacts

Cosmetic_Contact_Lenses

My primary focus at the OpticalJedi will always be on eyeglasses, but today I’m taking a small foray into the realm of Contact Lenses to discuss care and maintenance…and sourcing of contacts.

There has recently been many advertisements on Facebook and Twitter for a new contact lens company.  They claim to be able to provide the exact same contacts you’ve always been wearing at a dramatically lower cost.  I am not here to say whether or not their product is good.  But I’m here to provide some warnings about getting contact lenses from a source of this nature.

Contact Lenses are a Medical Device

The FDA has categorized contact lenses as a medical device.  And for good reason! Contact lenses fit directly onto your cornea.  This direct contact with an exposed portion of your body creates many risks that do not exist with eyeglasses.

When a corrective lens sits directly on your cornea, it creates a warm, moist area ideal for growing bacteria.  If lenses are not cleaned regularly (daily disposables excluded for obvious reasons) the contact lens acts as an incubator, allowing bacteria and viruses to grow and multiply at an alarming rate.  Wearing contact lenses when you are sick, can be a dangerous proposition.

Even I, an eyecare professional, had a problem with an eye infection because of contact lens use.  I thought I had fully recovered from a flu, so I started wearing my contacts again.  I had been mistaken.  I ended up with a viral flare incubated under the contact lens which created a corneal ulcer.

Contact_Lens_Related_Small_Corneal_Ulcer_with_Sodium_Fluorescein_Staining_1

Corneal Ulcer

It may not look like much, but a corneal ulcer is extremely painful, creates strong photophobia (light sensitivity), and in my case, led to my developing a reaction to most contact lens materials.  I could not wear contacts for a full 10 years after this happened.

But What If I’m Only Wearing Them For Halloween?

The American Academy of Ophthalmology(AAO) warns that many of the decorative contact lenses that can be bought online and may not be approved for use by the Food and Drug Administration. (Contact lenses are considered “medical devices” by the FDA and are regulated. Ones that are sold over-the-counter without a prescription are unregulated and technically breaking the law, per the FDA.) – Source:Self.com

The Halloween contact lenses can be even more dangerous.  Contact lenses are more than just a prescription correction.  There are additional parameters which effect how the lens sits on your eye.  Everyone’s cornea has a slightly different curvature.  If the lens does not match the curve of your eye, it can be very uncomfortable, or they might not even stay in the eye, if the curve difference is too extreme.  When you order your contacts online, even if they have no correction, the curve and diameter measurements have to work for your eye or you run the risk of at least uncomfortable lenses, and at most an infection.

The additional concern you need to watch for, if you order contact lenses online, is that they may be made with potentially dangerous chemicals not found in more reputable brands and sources:

They can also contain potentially harmful ingredients. Research published in the journal Eye & Contact Lens in 2015 found that non-prescription contact lenses can contain chlorine and iron, among other potentially toxic ingredients, which are used to tint and create patterns on the lenses. During the study, scientists found that one pair seeped chlorine after a routine rinse, and others had an uneven texture that could scratch the surface of the wearer’s eye.

Anterior_vitreous_cells.jpg

Keratitis Infiltrates

It’s very important to keep in mind that the pigments and dyes used to paint the lenses for theatrical/Halloween can be very dangerous, or even outright poisonous.  The best way to make sure the lens you are using is safe, is to get it from a reputable eyecare professional.  Also keep in mind, if you wish to get cosmetic contact lenses for a Halloween costume, it can take as long as 3-4 weeks to have them manufactured, after you have your contact lens fitting.  If you need them this Halloween, you need to order ASAP.

 

 

In Which a Theme Develops

So, it looks like we’ve stumbled onto a new segment here at the OJ…Ask the Jedi is now a thing.  

I received another email today with some additional questions on fitting advice.  Here you go.

Today’s Email

Hi Jedi Master!

I read the “A Piece of Correspondence” article and appreciate all the specific advice you provide to us consumers as to lenses, frames, etc. I myself don’t have my actual prescription in front of me, it’s totally inadequate info but I remember being told two years ago that I was a -9. In other words, a blind bat with a high minus. I will be trying a VSP doc next February, but have had some talks with his office people beforehand. I went ahead and purchased a Prodesign 4729 frame, which I have been told works from a size standpoint (47/19/145 with a 39mm vertical measurement). That being said, the width of the frame where the lenses fit into (does that even have a name?) is somewhat smaller than my current Moscot frame. The Moscot measures 4-5 mm, while the Prodesign (which I don’t have in front of me) is probably 2-3 mm. Considering that my optometrist is going to probably going to recommend a Shamir Autograph III progressive in 1.74, do you believe those lenses will fit into that Prodesign frame, both practically and aesthetically?

A few more questions, if you don’t mind: 1) my current Moscots suffer from a bad case of “ring glare” on the inside of the frame, it’s the first thing you notice. My memory tells me we did a satin polish, which did not help. There’s not much on the subject, but the Jedis on [a professional optical site] seem to recommend not polishing the lenses at all. What do you think? If so, is it still possible to roll the lenses and to polish the visible edges of the lenses only?; 2) I am definitely going to get Transitions Signature, but the 1.74 lenses reduce my AR coating choices. My optometrist says he prefers Unity (a.k.a. VSP) coating over the Shamir’s, but he did not specify which coating. The only one I can seem to read anything about is the new Techshield Blue. I am not so much concerned with Blue Light protection (which is provided in some measure by the Transitions) as having the best AR coating available for 1.74 lenses. Any feedback? I don’t believe any Crizal is available at all in 1.74, but I could be wrong. I know you would need my full prescription to really choose, but is it worth it perhaps to drop down to 1.67 for the greater choices of AR coatings? On the other hand, I like thin lenses.

My Response:

Thanks so much for reading my blog! First things first, while a -9.00 is strong, my mother was a -13.00 so you still have a ways to go to be the strongest I’ve dealt with.
I’m not sure what measurement you’re referring to that is between 2 and 5 mm.  Based on the little bit you’ve provided here I don’t see any issue with the Shamir Auto III lens for you.  the VSP Unity coatings are fine, but I do think there are better choices.  The Shamir lens is compatible with Crizal Sapphire, which has the best light transmission on the market.
The glare issues you’re referring to are probably because the lens was rolled as well as polished.  The rolling can make the edge look thinner from the side view, but it increases internal reflections rather dramatically.  To minimize the amount of ringing, you probably want to avoid the roll and polish.  I prefer to never polish my lenses because it does negatively impact the optics.  Generally speaking the satin polish does improve cosmetics though.  Transitions Signature really works pretty great now.  I think your color choices will be limited to grey only in a 1.74 but that’s not necessarily a bad thing.  You can also get Graphite Green and Brown in 1.67.
If you do a Varilux digital progressive (think X Design, Physio DRX, etc.) you will get additional blue light protection as well.

PS- I don’t wish to countermand the recommendations of the doctors and opticians out there.  They are always going to be more deeply familiar with the prescription, frame and lens fit of the patient than I will (unless they come see me).  But based on the information provided, these would be my recommendations.  Knowing specifics of frame fit (i.e. actually seeing how it sits on the face) can sometimes change what my recommendations might be.

If you’d like to contact me for you own piece of Correspondence, please feel free to shoot me an email!

A Piece of Correspondence

Today, I received an email from a reader, and with his permission, I am sharing it here.  I think the questions raised are excellent, and could  be quite helpful to some of you other readers out there!

The Message & Response
My Responses are set aside by color and italics

Dear Optical Jedi:

I have a “heavy” prescription. In September 2005…I chose [a smaller frame] to be better for my prescription, at least in terms of weight, minimizing the “Coke bottle” effect, etc.

In September 2005, my prescription was
OD -7.25 = -1.00 x 180
OS -7.75 = -2.00 x 160
add +2.25

I have an eye exam scheduled for early October, and I’m confident I’ll need new lenses, if only because of further deterioration in my near vision.

I’ve worn progressives for nearly 30 years, and never had any adaptation problems. I started with Varilux Comfort. I switched to the Ipseo because I was advised I’d see a substantial improvement in my vision and experience [pun intended].

Opticians at three different practices have said, without any guarantee, that my Lindbergs may be reused again. Accordingly, I’m looking for:
* new lenses for my Lindberg frame, which I’ll buy with my FSA; and
* backup and sunglasses via my Davis Vision benefit.

Davis, I’ve been told, offers the Shamir InTouch and MyFocal HD as its “ultra” progressives the Varilux Physio and Zeiss GT2, among others, as its “premium” progressives.

The three opticians I’ve visited all want to keep me with Varilux, although I’m willing to change companies, if either I can get something likely to work better for me, or I can get substantially the same functionality for less.

For my primary pair, two of the three opticians recommend the Physio W3+ Fit. One recommends the “S”; the other two advise against it (and say my price would be the same for the W3+, the W3+ Fit, or the S.) The “X” is not recommended primarily because of lack of either personal or customer experience. No one has mentioned the Physio DRX, which you recommend for myopes.

Before getting to some specific questions, I should add that I’m nearly 68 and work in a professional environment. Most of my work time is spent either using a computer or at meetings. I drive to and from work. I do spend time outdoors on weekends, see movies and plays, etc., but that’s not my primary focus.

So, here are some questions I’d appreciate help thinking through:

1. Is it reasonable to combine more advanced primary lenses with older technology sunglasses and backup glasses?
I have seen some patients have difficulty with this, but if you had no trouble switching lens designs in the past, I seriously doubt you will have any concerns.  I tend to use a primiary design for most of my glasses, but I do switch designs (i.e. Maui Jim cannot use a Varilux design) and have very little difficulty with it.  Sometimes there can be a momentary adjustment as your eye adjusts to a new design, but it shouldn’t last more than a couple of moments.

2. If so, and considering the limited selection from Davis Vision, what reasons are there, if any, to consider switching from Varilux to Shamir?
I’m sorry you have Davis Vision.  There limited formulary is one of the most frustrating aspects of fitting a Presbyope.  As a rule, Shamir works very well.  They created the original molds of designs going back 40-60 years ago, that were used for companies such as Varilux.  I have no personal wearing experience with the Shamirs offered by Davis, but their lens tend to be very comfortable.  Before the advent of the X Design from Varilux I would say that the Autograph II from Shamir was probably my favorite design to wear.

3. Why would it be inadvisable, if it would be, to choose different brands for my primary lenses and Davis Vision lenses?
Again, it’s not necessarily a problem, but the greater the difference in technology between designs, the harder it is to “code switch.”  For example, if you were to mix a budget solution like an Essilor Ovation, with an X Design, you would probably find it very jarring and difficult.  Specifically the behavior in the near and mid-range zones are quite different and you would do more hunting for your reading zone in the basic design.

3. Put otherwise, what can you say for my general situation about (a) Physio v. MyFocal; and (b) Varilux [W3+, W3+ Fit, Physio DRX, “X,” ?] v. Shamir III or II (your Shamir recommendation in your blog article)?
The amount of astigmatism correction you have starts to creep up in importance of design choice.  The Physio is honestly not something I would call premium and it frustrates me that Davis categorizes it so.  Physio is not a bad lens, but the edges of the clear zones are more “canyon-like” and you drift into the blurry distortion zones faster (i.e. you’ll need to point your nose more).  I personally did not care for the W3+ for myself.  I have a -3.50 Rx with a +1.75 add.  I found it a little tight and frustrating.  The DRX is generally more comfrotable for a Myope, as you’ve noted that I recommend.  The biggest variable for that recommendation is just how close the frame sits to your eyes.  If you have a longer vertex distance, it can cause more frustration with narrowing your fields.  You should be quite comfortable wearing both Shamir designs with no difficulty.

4. How significant is the difference likely to be for me between 1.67 and 1.74? Relatedly, when Varilux’s availability chart says that an A/R coating is “systematic” with the 1.74 lenses, does this mean that the cost is built in to the price of the lens or that, if I buy a 1.74 lens, I have to but one of the Crizal coatings?
I have a calculator available to me which allows me to see rather specifically the differences in thickness based on Rx, frame, and fitting measurements.  Doing a rough estimate of frame size and PD measurement, you would see approximately a .6 mm edge thickness difference going to a 1.74 hi index.  But, there can be significant concerns with 1.74 and grooving for a Corona frame.  Lindberg specifically recommends 1.67 for their frames because of its tensile strength.  It can handle the grooving better.  The reference to systematic is indicating that 1.74 cannot be purchased without including a Crizal Alize or better coating.  You still have to pay for the coating as well, but given the light loss inherent in the thinner material, the coating is required to guarantee quality of vision.

Finally, I’d add that given your Rx, lifestyle, and other notes you have given me, I think that the Crizal Sapphire 360 would be an extremely wise choice for you.   If you were to switch frames to a full framed/non-grooved model I would suggest switching to the 1.74 to minimize thickness, but in the lindbeg I would stay in 1.67.  I also think you’re probably a very good candidate for Transitions Signature.

I suggest the Shamir II mostly because it’s the one I’ve worn and I know it’s good.  I’ve heard positive feedback from friends in the industry regarding the Shamir Autograph III, but I don’t have the personal experience to add to it.  My understanding is that the zones are wider.  

Between a Varilux S and a Varilux X it’s quantitatively different.  I’m not a very big fan of the S and how it performs.  It’s a great lens, but I would not call it the best lens.  The X is the best thing I’ve worn.  It’s a significant improvement in function.  X would be the one I would recommend most strongly for all purposes.  I understand the desire to stay with Varilux.  Once you know a brand and it’s characteristics, it’s easier to work with just that collection.  You won’t see poorly in a Varilux, but the standard Physio is just not as versatile a lens.  If you spend a lot of time in front of a computer you’ll be much happier in an X Design, or a Shamir Autograph (either II or III).  Again, I don’t have personal experience with the MyFocal so I can’t be too specific on what to expect with it, but it is lower down the scale of the Shamir products from the Autograph series.

The big differences in the X Design versus other lens choices is that the width of the field for midrange and near is significantly larger (almost the full width of the lens), and the depth of field in each zone is more significant.  So, for example in the bottom “near” zone you can stretch out to arms length away.

Take Away

I am here to answer questions.  Sometimes that’s from my posts, but it can also be from your directed questions for me.  If you have anything you’d like me to tackle, on a personal note or not, please feel free to email me opticalric@gmail.com and of course you can always reach out to my Facebook and Twitter handles too.