issue with a patients glasses.

**queens optician** · 10-25-2011, 08:48 PM

So I have an issue. There is a patient that picked up glasses that checked out perfectly. The RX is OD -1.00 +4.00 x30 OS -1.50 +3.00 x135 PD 64, with a 54 A avaiator shape. She stated that she was having issues with the glasses 2 weeks later. The patient took her glasses back to the DR and his assistant checked the glasses stating that the PD was off by 10, being 74 and that there was a vertical imbalance of 1.00 BU. Can this be fix and should it be fixed??

**uncut** · 10-25-2011, 09:03 PM

Welcome to Optiboard queens optician! Nice first post

.

The answer to your question is yes it can be fixed, and should be fixed.

**queens optician** · 10-25-2011, 09:07 PM

Thanks. See thats what I thought, but I was told that should not be the solution. The glasses were checked in correctly.

**uncut** · 10-25-2011, 09:12 PM

Rule #1. When in doubt, or there is conflicting results, check again, preferably with a different lensometer, and/or operator.

If there is vertical imbalance, coupled with horizontal unwanted prism(IPD inaccurate), the total prism the person is dealing with will be uncomfortable. What has the person experienced?

**jcamp** · 10-25-2011, 09:30 PM

Did you neutralize the lenses in question?

**jcamp** · 10-25-2011, 09:33 PM

Just wondering if Dr's assistant and you got same results?

**Wes** · 10-25-2011, 11:03 PM

Here's the deal, you have two VERY significant cylinders at oblique axes. What you need to do is measure each lens at the ordered pd (assuming 32/32?) and ordered OC height (half B if you didn't specify) and determine power and prism at these points. Do not just look for an optical center, because you will most likely have difficulty determining exactly where it is. In any lens that corrects for mixed astigmatism, there will be a meridian with zero power that can make it difficult to properly read for inexperienced opticians.
If all of that checks out, (and even if it doesn't) compare the rx to the patient's previous glasses. High astigmats do not like to have their axes changed.
Welcome to optiboard. Just curious, are you certified and licensed?

**rdcoach5** · 10-26-2011, 06:39 AM

No one has mentioned yet the inherent imbalance in this Rx and the therefore great effect of POW. Not to mention a 54 pilot is a bad frame choice. As long as you are re-making for PD, try to switch the patient to a smaller B dimension frame and one that you can get proper panto. Check old base curve and make sure centers are the same and match vertex and wrap as well as lens material. If the old glasses axis is much different, that's a warning flag. Let us know your results.

**optilady1** · 10-26-2011, 08:10 AM

Originally Posted by Wes

Here's the deal, you have two VERY significant cylinders at oblique axes. What you need to do is measure each lens at the ordered pd (assuming 32/32?) and ordered OC height (half B if you didn't specify) and determine power and prism at these points. Do not just look for an optical center, because you will most likely have difficulty determining exactly where it is. In any lens that corrects for mixed astigmatism, there will be a meridian with zero power that can make it difficult to properly read for inexperienced opticians.
If all of that checks out, (and even if it doesn't) compare the rx to the patient's previous glasses. High astigmats do not like to have their axes changed.
Welcome to optiboard. Just curious, are you certified and licensed?

+1. My first thoughts were along the same line. (I guess this means I'm as smart as you Wes

). Theres very little power at the 180 on either lens, so pd shouldn't be an issue. As for the vertical, there's none in the os (it's early, I think I did the math right). Anyways, you need to re-check everything yourself, and if you don't feel comfortable doing some math, find someone who can.

And welcome to the wonderful world of optiboard. There are lots of brains here to help ya out.

**finefocus** · 10-26-2011, 11:31 AM

Originally Posted by optilady1

+1. My first thoughts were along the same line. (I guess this means I'm as smart as you Wes

). Theres very little power at the 180 on either lens, so pd shouldn't be an issue. As for the vertical, there's none in the os (it's early, I think I did the math right). Anyways, you need to re-check everything yourself, and if you don't feel comfortable doing some math, find someone who can.

And welcome to the wonderful world of optiboard. There are lots of brains here to help ya out.

Yes, your math is perfect; the OS is plano at both 90 and 180. The OD is also plano at 180. Queens, you probably know that the PD isn't the issue, it's the unwanted prism generated if the PD is wrong. This PD could be off by a hundred yards and it wouldn't matter (and as noted above there is no PD in planos).

Also, when checking for PD where one lens is significantly higher power than the other, check the strong one first.