Looking for advice with patient having trouble with new Rx

[Mr. Finney]

Hey everyone, looking for some advice. This is a fairly typical situation, I'm sure, but how would you handle it?

Patient gets new Rx of OD -0.75 -1.50 x075, Add +2.50, OS -1.00 -2.25 x085, Add +2.50. Old Rx was OD -2.00 -1.75 x100, Add +2.75, OS -1.50 -2.50 x085, Add +2.75.

Patient is complaining of decreased acuity in the OD periphery as compared to old lenses. Same frame, same lens design, same material and A/R, same fitting height and PDs.

My first thought is yeah, patient went from -3.65 @ 180 to only -2.00. Maybe that's taking too much away?

Patient goes back to doctor, who tells patient that the Rx is correct, and draws an hourglass and explains that the new lenses must have too small of an intermediate area, and to tell the Optician to make lenses with wider intermediate. Ummmmmmm. Ok.

Wouldn't the smaller change from distance to near coupled with a lower add effectively WIDEN the intermediate?? Could it be that the 25 degree change in axis is the issue? Maybe the patient really likes the extra minus at the 180? Am I missing something obvious here???

Thanks for any help!

[becc971]

i would think that the big change warrants some getting used to. even the axis change OD is pretty huge. I would make sure they wore them for at least a few days before doing any changes though.

i've had good luck with the definity for patients who need a wider intermediate.

[fjpod]

you can't rule out Dr. error here. That is a large change od in sphere and cyl axis for anyone to swallow. That would sure explain blur in the OD. What is the age of the patient? Often older people developing cataracts will show large axis swings but don't actually accept it in their glasses. I can't tell you how many times in my daily practice that I modify my manifest refraction before writing the Rx to better suit a patients needs....

[Mr. Finney]

Patient is about 65. Apparently cataracts are trace right now. Has been wearing new Rx for 4 weeks now.

[CCGREEN]

If he has been wearing the Rx for 4 weeks, on his face, not in his pocket. Then he has had plenty of time to acclimate to the Rx if he is going to at all. Something needs to change. I feel the Rx in the OD could be a bit much all at once. Would be nice if it could be backed off. How about base curve? You didn't say anything about that.
Sounds like the pt went back and the dr and him addressed the width of the intermediate and NOT the visual acuity issue. So is the patient telling you one thing and then the Dr something different. Some of this could be communication.

[Mr. Finney]

Yes I agree, she's been wearing them long enough to adapt. I have not checked the base curve, but I would think it's probably a bit steeper now with the hyperopic shift. As for communication, or lack of parallel communication, that's possible. Do note, however, the issue only exists OD. Her field of vision and acuity OS are fine. To me, that rules out the doctor's argument of "they need to make you better lenses like the ones we offer with our fancy-schmancy Visioffice". Where's that puke emoticon?

[Robert Martellaro]

Patient is complaining of decreased acuity in the OD periphery as compared to old lenses. Same frame, same lens design, same material and A/R, same fitting height and PDs.

Distance OD periphery? The blur might be expected if the base curve wasn't changed to match the Rx. Using identical base curves when there is anisometropia makes sense with some semifinished PAL designs.

Patient goes back to doctor, who tells patient that the Rx is correct, and draws an hourglass and explains that the new lenses must have too small of an intermediate area, and to tell the Optician to make lenses with wider intermediate

So is it the distance or intermediate off-axis?

Another reason for increased off-axis blur might be due to less minification from the lower minus Rx decreasing the apparent field of vision, bringing the unwanted astigmatism from the PAL optics into her field of view.

If both are happening, it would probably be additive, a double whammy so to speak. A highly optimized PAL design would help, maybe enough to make this go away.

And as fjpod says, if the refraction change is too much to handle, perspective-wise, it now becomes, potentially, a triple whammy, leaving you and your client pretty much screwed every which way.

Good luck,

[Mr. Finney]

Distance OD periphery? The blur might be expected if the base curve wasn't changed to match the Rx. Using identical base curves when there is anisometropia makes sense with some semifinished PAL designs.

No, her complaint is more with at and below the 180. She says distance is fine.

So is it the distance or intermediate off-axis?

Another reason for increased off-axis blur might be due to less minification from the lower minus Rx decreasing the apparent field of vision, bringing the unwanted astigmatism from the PAL optics into her field of view.

That's what I was thinking.

If both are happening, it would probably be additive, a double whammy so to speak. A highly optimized PAL design would help, maybe enough to make this go away.

Current lens is a Seiko Prestige 2 Wide, same as her old lens.

And as fjpod says, if the refraction change is too much to handle, perspective-wise, it now becomes, potentially, a triple whammy, leaving you and your client pretty much screwed every which way.

Agreed.

Good luck,

Thanks Robert!

[Robert Martellaro]

Your welcome Bryan. I'm not familiar with Seiko lenses, but a quick check says that this hard design PAL is surfaced on a free-form generator with software that corrects for off-axis error, so that probably rules out base curve issues. The perspective change minification-wise seems minor compared to the Rx change. Let us know how you resolved this!

Robert

[MakeOptics]

Another reason for increased off-axis blur might be due to less minification from the lower minus Rx decreasing the apparent field of vision, bringing the unwanted astigmatism from the PAL optics into her field of view.

Very astute observation, yes less compression in the lens (best way I have found to explain it to patients) will require more eye rotation putting the view into the danger zone.

PAL's with oblique power also have a very interesting phenomenon where the power error the mag error and the cyl error all split, so the more a prescription goes oblique the more problematic it can become especially with a decrease in power.

[Mr. Finney]

Very astute observation, yes less compression in the lens (best way I have found to explain it to patients) will require more eye rotation putting the view into the danger zone.

PAL's with oblique power also have a very interesting phenomenon where the power error the mag error and the cyl error all split, so the more a prescription goes oblique the more problematic it can become especially with a decrease in power.

Please forgive my ignorance MakeOptics, but what is that a map of? I'm not exactly adept at reading power graphs!

[rrgirl]

Perhaps I am being too simplistic, but... I have found that the Definity 3 has been my go to lens especially with my older patients as the extremely wide intermediate seems to help in everyday activities and the 'reverse' at the lower edge helps with the dizzy sensation that some of my plus patients have. While he is a Minus, he is much less minus than he used to be, so things may move differently in the near than he is used to. The smaller change from distance to near would widen the intermediate, but not signficantly. I suspect we may have an emerging cataract formation in the right eye? That may be the reason for the big reduction in distance power (OD), and the frustration with the near power. Image size difference. Make sure your heights are accurate individually... and remember, we minus folks LOVE that minus power. It makes us FEEL like we see better, even when we DON'T. (personal experience.) Tread softly with mentioning the cataract. His Doctor may not have told him yet, and you do NOT want to be the one. Just ask if he mentioned cataracts at all. Just speculating... also if the cataract is pulling enough to get that big of a change in axis, I wouldn't describe it a small.... must be a b to deal with for the patient. i have a feeling that is the main problem, everything is a different SHAPE to top it all off. You didn't mention the patient's occupation... is he perhaps an ENGINEER?????

[Mr. Finney]

Thanks for the replies everyone. STILL waiting for her to come back in so I can troubleshoot further.

[Mr. Finney]

Yes rrgirl, she's a Domestic Engineer.

[rrgirl]

They are often the MOST picky. and least adaptable. Good luck. It could just be that she likes the attention, and I wish that was a joke.

[sharpstick777]

What is her OS/OD DVA straight on in both pairs? I am guessing her DVA is not as good as she states. If you have a measured DVA that falls short of her BCVA in her original refraction, she needs an RX adjustment.

25 degrees is a lot of axis change. She could have adapted to the old rx even if it wasn't correct, I call it Petropia. often splitting the change in degrees 60/40, then testing the DVA in a trial frame will solve this issue. If you can achieve the same DVA centrally with less change you will solve your problem. I have also used "training" lenses for 3 months to resolve a large Rx change, that are half the change, and then go to the full change.

[Mr. Finney]

UPDATE: Tried a change in adjustment, added a bit of face form and panto to move that peripheral blur back out of her line of sight (plastic frame, so can't change vertex), while in the shop she said it was better but came back and said her central clarity now suffered. Experimented with +/-0.50 flippers to see how it affected both central and peripheral acuities, one time the + was better, the next time the - was better. Told her it appeared to me the Rx is accurate and that the frame fit was good, and also that maybe the Dr should have stepped her into the Rx for adaptation's sake, but that eventually she would arrive at this same Rx. She agreed and purchased a pair of sunwear also. Thanks for everyone's thoughts and help!