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Trial frames vs. phoroptor to refract

Discussion in 'Optometry' started by silverleaf, Apr 23, 2007.

  1. silverleaf

    silverleaf 2+ Year Member

    Apr 8, 2007
    I was taught that in the USA, phoroptors are mainly used for refraction, and in the UK, trial frames are the go. Here in Australia, it depends.
    I find the phoroptor really useful for refraction, and try and use it as much as possible. It is much easier for ret and less time consuming overall. However, there are some disadvantages associated with using the phoroptor:

    -Vertex distance inaccuracy for high Rx
    -Unco-operative and low vision patients (discomfort, moving their heads back and changing vertex distance)
    -Sometimes it's just psychological - seeing lenses physically being changed can give more accuracy
    -Prescribing near adds: despite the binocular cross cyl method, I think converging in downgaze seems a more natural reading position for the patient

    Now I know a lot (if not most!) of you on this forum are from the you think the above reasons are valid? Am I wasting my time using the trial frame? Thanks!
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  3. 4Eyes

    4Eyes 5+ Year Member

    Oct 30, 2005
    Using the trial frame is not a waste of time...the reasons you listed are valid. Though phoropter is the norm, we are taught trial frame refraction for a reason. I know I will use my trial set a lot more in a few months when I see more low vision patients. Right now, I mostly just use my trial lenses to see if the patient will accept more plus found during refraction with the phoropter or if the add needs any modification from what I found with BCC or PBU.
  4. swiftiii

    swiftiii Member 2+ Year Member

    Apr 23, 2006
    Fort Lauderdale, FL
    There is something that I have been wondering for a long time about this. They say you want to trial frame someone to see if the prescription you have found is a good "fit." The thing is, when I put on a -6 with 2D of cyl on top, I find the whole thing to be terribly distorting...even though this is my typical presciption. I would think that anyone with a decent amount refractive error is going to suffer the same problem. So I guess my question is, how good is trial framing really when you're not checking a minor rx? I'm really having a hard time appreciating its benefit.
  5. bournehall

    bournehall 2+ Year Member

    Oct 5, 2006
    Wow, brings back memories. I moonlighted in the UK for 3 years while stationed there in the AF. Loved the experience except for the brutal aspect of trial frame refractions. Sure, it is like anything else you do...the more you do it the easier and faster it becomes. But, I would say that refractions with a phoropter are way more accurate in that it is easier to bracket back and forth and pin it down better. Assigning the add power is a no brainer but is easier with a phoropter. I see no reason whatsoever in using trial frame refractions except for home bound, nursing home, etc. You make a good point about the psychological aspect in that I asked the UK optometrist why on earth they don't embrace technology and use the freakin phoropter? He responded that...the brits like things slow and enjoy the time you spend with them. I don't even know where the trial frame is in our office.

  6. bournehall

    bournehall 2+ Year Member

    Oct 5, 2006
    If a person needs to check the validity of their refraction by putting the Rx in a trial frame they need to learn how to accurately refract in the first place.


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