here's the script:
+0.50-8.00X030
+0.50-1.25X035
+2.50
fitting height 20
need a pal,transition grey in poly or trivex
any suggestions?
thanx in advance
jamie
here's the script:
+0.50-8.00X030
+0.50-1.25X035
+2.50
fitting height 20
need a pal,transition grey in poly or trivex
any suggestions?
thanx in advance
jamie
I'll throw one out there: Augen Centurion
Bryan Finley, Florida Board Certified Licensed Dispensing Optician
I have never heard of that lens. I was thinking a digital lens but I am under the impression I need a semi finished traditionally surfaced lens. Pt is in a comfort now. Also, no slab-off now in his glasses but I was told it is recommended by the lab tech.
Centurion is a digital mold lens. I think you'll be out of luck with digitally surfaced lenses, too much cyl. If he's not wearing a slaboff now, and not complaining about poor near vision, and the Rx didn't change much, I wouldn't do it. Also, have you considered keeping him in the Comfort, maybe a 1.60?
Bryan Finley, Florida Board Certified Licensed Dispensing Optician
Yes that was my fall back plan was to keep him in comfort. I was just trying to get him in a more modern lens design, but I guess if it is not broken don't try to fix it. I do need impact resistance of poly or trivex, which is recommended on the rx. I was recommended an image if I wanted trivex.
Comfort in poly transition- cyl is well out of range. Not available in trivex.
What was the previous RX?
Jamie,
The safest course is to stay with the Comfort. There's 5 D of power difference at 90. With a 4mm drop, there will be 2 D of VI (vertical imbalance) at the distance point, and well over, depending on the reading depth, 5 D of VI at the near point. If the old Rx was the same, and the patient is non-symptomatic, then it might be best to keep everything the same.
However, that doesn't mean that your client won't have increased visual comfort if you reduce the VI. You might want to talk to the doctor about vertical phorias, if any, noted during the exam. I don't recommend slabbed PALs, preferring separate readers for extended close tasks. Correcting the distance VI is problematic; you could use a lens with less or no drop, but then the change in PAL design might cause unforeseen negative consequences. Surfacing a compensating prism would neutralize the distance VI, but increase the VI at near, by an amount that might preclude fusion.
If there is a change in Rx that is increasing the VI, then you should assume that the increase might not be tolerated, and be more aggressive in your approach. One possible solution is to use segmented and slabbed multifocals, where the VI can be reduced to low levels at both distance and near. Separate distance and near SV glasses are another possibility.
Hope this helps.
Science is a way of trying not to fool yourself. - Richard P. Feynman
Experience is the hardest teacher. She gives the test before the lesson.
The rx is unchanged. This is a corneal transplant patient. He is currently in a Comfort in poly, the lab was able to grind the extra diopters of cyl. I realize obviously that the comfort doesnt come in trivex,which is why I was thinking image might work. The doctor thinks that slab off would not be a good idea since it is not in his current glasses.
jamie
pinhole spectacles...ok, I'm no help.
If he's wearing Comfort now with no problem then keep him in Comfort. What are you gaining by switching him? Don't make problems for yourself.
You can not get the Comfort in a -8.00 cyl. (Unless my info is off).
I just put a -6.75 cyl in a 1.67 gradal top transition. He loves them and has no complaints
od was +2.25 -6.75 x 067 os was -0.50 -400 x 090 add 2.25... 30/31 pd 19 seg. Frame was a Silver Dollar BTCF 3000 series with custom shape a-51 b-34
Last edited by ronnie daniels; 02-11-2010 at 02:13 PM.
and speaking of slab off i seen ya askin about it. I dont think theyre is any rule of thumb on a slab off i was always told 2.25 imbalance in the sphere is borderline slab off. I did a job the other day too with a 6.75 imbalance in the sphere -6.25 in the right and +0.50 in the left with no slaboff and she says its the best bifocal script shes had
Jamie, Does the patient have good binocular vision with this Rx?
It's the power in the vertical that counts and this looks like about a 3^ vertical imbalance in the near zone which many patients can fuse.
Also a lot of patients with big power differences just shut off the vision in one eye when using a multifocal but don't realize it.
Kind regards-:cheers:
yea ive been saying she must be suppressing her +.50 eye because she has just had cataracts on that eye and the 6 weeks before she got her final rx we just edged her a plano to wear and she only used the other eye to read.
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