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
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.
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 email@example.com and of course you can always reach out to my Facebook and Twitter handles too.
2 thoughts on “A Piece of Correspondence”
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