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Ophthalmology & Optometry/Understanding Rx Change & Rimless Lens suggestion

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QUESTION: Regarding my most recent spectacle prescription change: I am nearsighted. My prescription usually gets stronger every couple of years. My understanding is that it will never get less strong for a nearsighted person. Most recently my Rx went from OD=-1.25 to OD=-1.5 as expected, but my OS went from -2 to -1.75 with a -.5 cylinder (axis 135).  This is the first correction for astigmatism that I have seen on my prescription.  The receptionist at the optical facility advised me that this is a stronger prescription for my OS, but it doesn't make sense to me since the number decreased.

Also, I love, love, love  fully rimless, lightweight spectacles. For the past 10+ years I have been wearing Silhouettes with polycarbonate. Now that I have astigmatism, should I consider a change in the lens material or shape? I tried on several new options and really liked the way a wider lens looked on my face (which really isn't that wide on me, since my lens sizes are generally 49mm and my PD is 57). Should I stick with symmetrical lens shapes now that I have astigmatism? Do you think I should move to Trivex from polycarbonate? Lastly, I am considering Transitions or another brand of light-sensitive lenses for the first time. Have you seen whether this is as reliable on Trivex as it is on polycarbonate? Thank you for your time.

ANSWER:
Kindra,
It is very likely that your prescription will change over time but generally does not get less myopic. So your understanding of that is correct. The reason you were told your prescription has gotten stronger is because of the cylinder.

When you have a correction for astigmatism the numbers have more impact on how you see than a spherical prescription would because instead of one plane of focus being corrected for there now are two. It is not at all uncommon and you might notice a short adaption period to the new prescription that lasts a day up to several depending on how your brain tolerates the change. If you like I can go into greater detail on what an astigmatism is and how it often necessitates an adaption period.

You prescription change would not require a change in frame or lens material. You should be fine getting what you have always gotten if that is what you are comfortable with and want again. In terms of size, the general rule is optical and aesthetic, keep your eyes as close to the center of the lenses as you can.

As to Transitions, people generally love them or hate them I fall into the “to each his own” category. They do not work as a sunglass when driving, which is when I wear sunglasses and I want polarized sunglasses, nor do dress glasses usually have the large wrap around lenses sunglasses do so unless you wear a cap so much light enters your eyes from above and the sides that the benefit is negligible at best. But some people love them and have worn them for years.


---------- FOLLOW-UP ----------

QUESTION: Hi. Thanks again for the answer. I just received my new glasses and I feel awkward as I move through space when I have them on. I was hoping you could shed some light on possible causes for this. The feeling is not exactly dizziness, it is more of a depth perception change. The ground seems farther away than usual, as if I am walking on high shoes.

Could it be that I need to become accustomed to wearing a prescription for astigmatism, since this is my first diagnosis (although it is very minor). Or is it more likely that the Rx or the pupilary distance is not correct in the lenses?

Thank you for your time.

Answer
Kindra,

I'm happy to follow up with your progress. I'm on the road again and want to give you a proper answer, which I will do later this evening.

Short answer its likely the astigmatism. But the long answer is very cool and I think you'll like it.



Kindra,

I wrote the long and more interesting answer to your follow up the night I posted the brief answer and thought I had posted it, but I just answered another question and looked to see if you had read your follow up and noticed that it never posted. I am sorry for the mistake and delay.

The understanding to your condition lay in the fact that the eyes collect light, but it is the brain that “sees”. Over time your cornea can, like other parts of your eye, change. The changes cause the image focused on your retina to also change. Your brain, being the organ that processes all input data, “knows” certain things that have to equal the input information.

As the astigmatism develops (astigmatism is the surface of the cornea warping) the image of a door frame no longer consists of square corners and plum sides. Telephone poles are no longer exactly vertical and stars are no longer seen as points of light. Imagine walking through a funhouse every day, everywhere you went, not so fun. So your brain makes adjustments so that the bad input data is “matched” to the known reality and as a result you continue to walk and drive and see largely unaffected.  The remarkable compensatory ability of your mind at work.
Now you sit down and put on a pair of glasses that changes the image on your retina instantaneously to “correct” and your brain is forced to adapt instantly to the same change that may have taken a year or more to gradually occur. Your brain is having to reverse all the compensation it has been doing to keep you out of the fun house with no warning. What you, and countless others are “feeling” is your brain learning.

The symptoms can be vague or pronounced, last a few weeks or no time at all, it all varies with the individual. I have seen people wear the wrong prescription for a year, I’m talking way wrong not just a little wrong, and when I ask them how their glasses are working they say they are “fine,” while others can have glasses made within tolerance and have difficulty, weeks and weeks or more, adapting. Sometimes prescription changes are so significant that the doctors won’t give them the “full Rx” because they know the patient could not tolerate the change.

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Robert Sobotor LDO

Expertise

Eye Glasses: fit, adjustment, and function Frames and Lenses: materials, benefits, limitations,progressive vs. bi-focal and adaptation Contact Lenses: tips on wearing, insertion and removal, comfort and proper cleaning and care Visual Complaints: Whether you have a history of unresolved visual complaints, never had a pair of glasses “feel right” or “I saw better out of my old pair” I can help troubleshoot visual complaints resulting from new glasses by determining, based on your observations and feelings, what the likely causes are and explaining them to you in a way that gives you a clear understanding and a shorter adaptation period. Contact lens Care: Tips and suggestions that I have used to teach first time contact lens wearers, even pre-teen and adolescent children, to quickly give them the skills and confidence to put in and remove their contact lenses. Tips on getting them in fast in the morning and out quickly at night without having that itchy feeling when you remove them. I can explain to you the makeup of the tear layer and how it can directly affect the comfort of your contacts based on little thing like computer use, heating and air in the car and office, that cloudy afternoon vision or dry feeling later in the day. Lens Recommendation: Based on your prescription I can advise what lens materials and designs are best suited to your needs and which ones to avoid as well as direction on frames designs that would complement the selection. Proper Frame Adjustment: I can help identify the problems associated with painful glasses that pinch, or squeeze. I can help you avoid getting a pair of glasses that constantly slide down your nose no matter how many times you get them adjusted. I can teach you what to look for in a frame that is right for you. I can explain how to look for a good quality frame that is not the most expensive in the room. I cannot diagnosis disease, prescribe or offer price specific advice or information.

Experience

My background is as a Licensed Optician with over twenty years experience. I have had industry-specific work published and held management positions with the largest optical retailing companies. I have had operational oversight of the dispensaries of both Ophthalmologists and Optometrists I have also held management positions in optical manufacturing to include specialty design RGP's and surface manufacturing, lens coating, and edging of spectacle lenses. My bench work, adjustment and repair, is in the tradition of the Guild opticians - focused on quality. I am proficient in all facets of eyewear, spectacle and Rigid Gas Permeable contact lens manufacture and modification. I provide an extension of the doctor’s standard of care throughout the entire dispensing process as I work with the patient to understand their diagnosis and develop the best solution toward remediation.

Publications
Eye Care Professional Magazine The Price Bluff- Relationship based business http://www.ecpmag.com/1webmagazine/2008/01jan/content/independent-ECP-pricing.asp Size Matters- The application of ANSI standards http://www.ecpmag.com/1webmagazine/2007/10oct/content/size-matters.asp

Education/Credentials
Licensed Dispensing Optician 1991 The American Board of Opticianry (ABO) certified 1990 National Contact Lens Examiners (NCLE) certificated 1991 Georgia State University 87-88 Oglethorpe University 03-04

Awards and Honors
Lens Crafters Presidents Pin for outstanding customer service

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