Results 1 to 16 of 16

Thread: need help. question about correcting with prism

  1. #1
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13

    Question need help. question about correcting with prism

    Hello. I have question about correcting phoria / trophia. let the picture describe the condition. My question is which one prescription is the best?. Click image for larger version. 

Name:	p prisma gambar.jpg 
Views:	66 
Size:	43.0 KB 
ID:	13949
    the best mean best for patient adaptation, best for cosmetic, or convenience or anything else.
    thank you

  2. #2
    Ghost in the OptiMachine Quince's Avatar
    Join Date
    Jan 2016
    Location
    Sebago ME
    Occupation
    Optical Laboratory Technician
    Posts
    1,172
    I'm not the best person to guide you in this, but it would be much easier to help with a written version of the script. There is obviously a lot of prism here and general I gravitate towards splitting between both eyes evenly (both vertical and horizontal) but that is also dependent of the power correction for each eye as well.
    Have I told you today how much I hate poly?

  3. #3
    One eye sees, the other feels OptiBoard Silver Supporter
    Join Date
    Jul 2002
    Location
    Wauwatosa Wi
    Occupation
    Dispensing Optician
    Posts
    5,458
    Quote Originally Posted by redb View Post
    Hello. I have question about correcting phoria / trophia. let the picture describe the condition. My question is which one prescription is the best?. Click image for larger version. 

Name:	p prisma gambar.jpg 
Views:	66 
Size:	43.0 KB 
ID:	13949
    the best mean best for patient adaptation, best for cosmetic, or convenience or anything else.
    thank you
    I've never seen this represented on grip paper so I might be interpreting this incorrectly.

    Eliminate examples #1 and #2 because the horizontal prism is base out.

    #3, #4, and #5 are the same, but #3 is written so that the prisms are equally split between both eyes, and this will allow for the best cosmetics and the least negative effects from chromatic aberration (unless the BCVA in one eye is considerably poorer in one eye, if so, split unevenly or put all of the prism in the bad eye).

    Best regards,

    Robert Martellaro
    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.



  4. #4
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by Quince View Post
    I'm not the best person to guide you in this, but it would be much easier to help with a written version of the script. There is obviously a lot of prism here and general I gravitate towards splitting between both eyes evenly (both vertical and horizontal) but that is also dependent of the power correction for each eye as well.
    thank you for your reply, the condition is left eye is normal 20/20 and right eye 20/20 but with oblique UP 4 Diopter and out 6 Diopter. Im just qurious can we use example 1 or 2 or only 3 is the best. thanks

  5. #5
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by Robert Martellaro View Post
    I've never seen this represented on grip paper so I might be interpreting this incorrectly.

    Eliminate examples #1 and #2 because the horizontal prism is base out.

    #3, #4, and #5 are the same, but #3 is written so that the prisms are equally split between both eyes, and this will allow for the best cosmetics and the least negative effects from chromatic aberration (unless the BCVA in one eye is considerably poorer in one eye, if so, split unevenly or put all of the prism in the bad eye).

    Best regards,

    Robert Martellaro
    Thank you for your reply, yes I'm describing with picture because i confuse how to describe it. Can you explain more why we have to eliminate example 1 & 2?
    Also. can we use progresive lens for example #3 for Presbiopya. thanks

  6. #6
    One eye sees, the other feels OptiBoard Silver Supporter
    Join Date
    Jul 2002
    Location
    Wauwatosa Wi
    Occupation
    Dispensing Optician
    Posts
    5,458
    Quote Originally Posted by redb View Post
    thank you for your reply, the condition is left eye is normal 20/20 and right eye 20/20 but with oblique UP 4 Diopter and out 6 Diopter. Im just qurious can we use example 1 or 2 or only 3 is the best. thanks
    #1 and #2 are the only examples that are equal to OD 4BU 6BO. Neither one is optimal for cosmetics. Examples #3, #4, and #5 are using 360 notation, and are equal to OD 4BU 6BI.
    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.



  7. #7
    One eye sees, the other feels OptiBoard Silver Supporter
    Join Date
    Jul 2002
    Location
    Wauwatosa Wi
    Occupation
    Dispensing Optician
    Posts
    5,458
    Quote Originally Posted by redb View Post
    Thank you for your reply, yes I'm describing with picture because i confuse how to describe it. Can you explain more why we have to eliminate example 1 & 2?
    Because I misinterpreted the grid paper, and that #3 was the only choice that showed prism split.

    Using the newly supplied Rx, the grid paper with rectangular coordinates, and the center as a reference point, and each box equal to one prism diopter, shows the right eye (small red square bottom left) as OD 2BD 3BO and OS 2BU 3BO. This contradicts what you stated is the written Rx above. Either the Rx you indicated above is written incorrectly, or I am still misinterpreting the graphic.

    Also. can we use progresive lens for example #3 for Presbiopya. thanks
    Generally yes, but with caveats.

    Best regards,

    Robert Martellaro
    Last edited by Robert Martellaro; 06-26-2018 at 10:26 AM.
    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.



  8. #8
    Master OptiBoarder
    Join Date
    Oct 2005
    Location
    new york
    Occupation
    Optometrist
    Posts
    3,749
    You can be dead on with your measurements but the patient might not be able or willing to wear what you find. The habitual Rx, the patient symptoms, if any, past experience, should all guide your decision.

  9. #9
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by fjpod View Post
    You can be dead on with your measurements but the patient might not be able or willing to wear what you find. The habitual Rx, the patient symptoms, if any, past experience, should all guide your decision.
    ok thank you for your advice

  10. #10
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by Robert Martellaro View Post
    Because I misinterpreted the grid paper, and that #3 was the only choice that showed prism split.

    Using the newly supplied Rx, the grid paper with rectangular coordinates, and the center as a reference point, and each box equal to one prism diopter, shows the right eye (small red square bottom left) as OD 2BD 3BO and OS 2BU 3BO. This contradicts what you stated is the written Rx above. Either the Rx you indicated above is written incorrectly, or I am still misinterpreting the graphic.

    Generally yes, but with caveats.

    Best regards,

    Robert Martellaro
    I mean the right eye condition is misalignment. but i understand your explanation and the correct written prescription. thankyou for all your answer

  11. #11
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    more question. how to measure PD for tropia?. which one is correct? #1 or #2. thanksClick image for larger version. 

Name:	tropia pd measuring.jpg 
Views:	22 
Size:	24.3 KB 
ID:	13963

  12. #12
    One eye sees, the other feels OptiBoard Silver Supporter
    Join Date
    Jul 2002
    Location
    Wauwatosa Wi
    Occupation
    Dispensing Optician
    Posts
    5,458
    Quote Originally Posted by redb View Post
    more question. how to measure PD for tropia?. which one is correct? #1 or #2. thanksClick image for larger version. 

Name:	tropia pd measuring.jpg 
Views:	22 
Size:	24.3 KB 
ID:	13963
    Of the two choices, #1, if the left eye is stuck in the exo position for all angles of gaze. The Rx might say "balance" for the left eye. But if you cover the right eye and the left eye points straight ahead, measure that position and use this value for the left monocular distance PD.

    Hope this helps,

    Robert Martellaro
    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.



  13. #13
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by Robert Martellaro View Post
    Of the two choices, #1, if the left eye is stuck in the exo position for all angles of gaze. The Rx might say "balance" for the left eye. But if you cover the right eye and the left eye points straight ahead, measure that position and use this value for the left monocular distance PD.

    Hope this helps,

    Robert Martellaro
    so the measurement is same. using monocular distance. thanks

  14. #14
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    I have experienced. found patient (40 yo) MPD R32 L32. with tropia in left eye cause by high blood pressure. during 2 months left eye covered, then when i open & check, found Missalignment 23 diopter prism base out. for temporary i give R 8 diopter base out L 9 D base out. (headache if put full prism). after 3 months check again the eyes back to normal (both eye) no tropia found.
    The question is, is that coincidence or normal for high blood pressue patient? thank you

  15. #15
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    9,385
    Muscle palsys can resolve, so yes.

  16. #16
    OptiBoard Apprentice
    Join Date
    Oct 2017
    Location
    indonesia
    Occupation
    Optical Retail
    Posts
    13
    Quote Originally Posted by drk View Post
    Muscle palsys can resolve, so yes.
    thank you. so thats normal right.
    sorry out of topic. Its about Myopia control lenses. Is there still many users? is the result works as expectation?

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Prism question
    By Marlon in forum Progressive Lens Discussion Forum
    Replies: 3
    Last Post: 11-10-2016, 01:13 AM
  2. Correcting esotropia by inducing prism
    By ilanh in forum General Optics and Eyecare Discussion Forum
    Replies: 8
    Last Post: 12-28-2013, 09:07 AM
  3. prism question
    By pseudonym in forum General Optics and Eyecare Discussion Forum
    Replies: 24
    Last Post: 09-24-2010, 01:45 PM
  4. Prism question
    By Bill MacGillivray in forum Ophthalmic Optics
    Replies: 5
    Last Post: 05-23-2010, 03:07 PM
  5. correcting prism
    By G.M. in forum General Optics and Eyecare Discussion Forum
    Replies: 20
    Last Post: 01-18-2006, 10:27 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •