Eye Care Community
Definition of 'Power' in monofocal IOL's ?
About This Community:

This patient support community is for discussions relating to eye care, cataracts, glaucoma, retinal detachment, eye infections, misaligned eyes, intra-ocular implants, refractive surgery (LASIK and CK), glasses, contact lenses, amblyopia, eye injuries, dry eyes, ocular allergy, eye pain and discomfort, pediatric eye disorders, eyelid and tearduct surgery, poor eyesight, and eye surgery.

Font Size:
A
A
A
Background:
Blank
Blank
Blank
Blank Blank

Definition of 'Power' in monofocal IOL's ?

# 1
       when 'measured'  pre-operatively for monofocal IOL for two eyes (to be done 2 weeks apart) is it 'usual' to have the measurements taken for both eyes at the same visit ?  Or is the 2nd eye's measurment determined by the outcome of the first eye's surgery results?
                When i see the word ''power' on the identification card for each eye, the numbers are different i.e. 15.5D and 16.5D .   I thought that 'power' in this case refers to a 'correct' power of vision (same idea as when one gets refracted for eyeglasses)  OR do the 'monofocals' (for distance only) come in 'one size fits all' insofar as 'distance' vision is concerned? Should both eyes have the same 'power' number?    as you can tell i'm 'confused' .
          Thank you so much in advance - Edythe
Tags: vision
Related Discussions
9 Comments Post a Comment
Blank
233488_tn?1310696703
1. BOth eyes are normally tested at the same time.
2. D in the IOl power is "diopter" a unit of bending power of light.
3. One size doe NOT fit all as far as power. One diameter fits all but the power will vary from person to person and eye to eye.

JCH MD
Blank
Avatar_n_tn
Thank you so very very much for answering my questions !!!  
First eye done june 11th...2nd june 25th.   Seeing distance clearly - amazing since i was very very nearsighed all my life. i am 71    :(
    one thing concerning me is that the  2-week old eye with the lower diopter (15.5)  done on june 11th is not seeing as 'sharply' for print material ( i.e. letters on t.v. screen closed-caption, etc) as is the most recently corrected eye (5 days ago).with 16.5D ....will this variance affect my distance when i try to focus on driving , read traffic signs, etc.
       don't know if this is relevant but in both eyes  i'm close to 20/25 post-op, plus the most recent eye with the 16.5 still has a very small pupil .... the surgeon stated it  will eventually match the 15.5D eye ((if its 'size'  has any 'cause/ 'affect' on what i described above)
        I still have to receive a prescription for my close-vision and i did have an astigmatism prior to surgery and i don't think that was corrected... i wanted to go with the 'simple' approach which would require glasses after surgery and i was wearing trifocals for at least the last 30 years.
        Thank you so much again for helping - it is greatly appreciated-Most Respectfully - Edythe
Blank
233488_tn?1310696703
Generally the eye with the lower IOL power will have better distance vision and the larger number better reading vision WITHOUT glasses.

JCH MD
Blank
Avatar_n_tn
Hello - i hope i didn't confuse the issue with my question regarding the two different D-readings ... i didn't know about the 'lower power' contributing to better distance, etc.   I just wanted to explain that i thought i was fitted for 'distance  only'  for the  IOL's in both eyes    - i will be getting a prescription later for 'reading/computer'  etc... but do i understand even ''without' the reading-glasses there is still some 'reading' vision in the 'monvision' -distance IOL's ?  if afirmative, will that 'difference' cause any problems distinguishing 'distance' since each eye 'D' number is different?  And is the  'difference'   between the two eyes in the D-readings done for 'that' purpose or was it just 'my' readings happening to end up like that?  Reason i ask is i heard that one can have a 'distance' IOL in one eye with a 'close' IOL in the other - i would not have elected for that ...  Many thanks again ...Edythe
Blank
233488_tn?1310696703
Your tests will generate a set of theoretical IOP powers that will leave you with residual refractive errors of "zero" (that would give good distance vision)  -1.00 (Good intermediate vision) or -2.00 (good reading vision). The ophthalmologist and patient then set the goals of uncorrected vision.

JCH MD
Blank
Avatar_n_tn
if i understand what you said when i get tested for glasses i will have 'no' correction for distance since my IOL's are distance only - Alcon Acrysoft IQ SN60WF  (13. Omm) & 6.Omm, both eyes -15 5.D & 16.5.D  but can receive correction for tri-focals (intermediate distance & close-up)...
           I also have an astigmatism - is correction for that condition ''added' to the distance vision also requiring that i wear glasses all the time for distance?  i would enjoy not wearing glasses for social occasions - walking into a room and actually faces !!
           Lastly,  even if the distance correction in glasses includes correction for the astigmatism, could i remove my glasses when desired for distance and still 'function' ?   been so nearsighted all my life the 'novelity'  of occasionally not wearing glasses for distance would be wonderful ... thank you again for your help = Edythe
Blank
233488_tn?1310696703
1. Picking IOL powers is NOT an exact science and there is an error factor of =/-  0.50 diopters (larger in very long or very short eyes).
2. A spherical IOL will not correct astigmatism. That would need to be done with placement of the incision, toric IOLs, limbal relaxing incisions or glasses or contact lens after the surgery.
3. You will not hurt you eye by not wearing glasses and you can go without them any time you want.

4. May people with perfect "plano" (window glass) RX after surgery for distances of greater than 20 feet wear no-line progressives, or trifocals or bifocials after surgery to see at intermediate and near.

JCH MD
Blank
Avatar_n_tn
Hello  ... - seems i have 'more' questions 'after' then 'before' the surgery! - LOL  but now i understand enough to realize i know 'nothing' !!  
            .. Since i opted for the standard IOL and had nothing done about the astigmatis then i understand that  i will definitely then need the astigmatism/intermediate/near glasses that will be prescribed in about 5 weeks and  as of yesterday's post-op check up both eyes are now seeing 20/20!!   (after all the visits tho i'm wondering if i memorized the eye chart?! - only kidding)  but i'm thrilled with the results and after a lifetime of being severely nearsighted (think Mr. Magoo)  it's nice to know i can 'socially' exist without glasses for distance.  
          Thank you again for your kind assistance and for patiently answering my questions - Most respectfully - Edythe
Blank
233488_tn?1310696703
-
Blank
Post a Comment
To
Blank
Weight Tracker
Weight Tracker
Start Tracking Now
Eye Care Community Resources
RSS Expert Activity
233488_tn?1310696703
Blank
New Cannabis Article from NORTH Mag...
Jul 20 by John C Hagan III, MD, FACS, FAAOBlank
242532_tn?1269553979
Blank
3 Reasons Why You are Still Binge E...
Jul 14 by Roger Gould, M.D.Blank
242532_tn?1269553979
Blank
Emotional Eating: What Your Closet ...
Jul 09 by Roger Gould, M.D.Blank
Top Eye Care Answerers
Avatar_m_tn
Blank
KayakerNC
NC
Avatar_f_tn
Blank
flossy93
CA
Avatar_m_tn
Blank
Craig10x
New York, NY
Avatar_n_tn
Blank
laura5121
Avatar_m_tn
Blank
PedroPrado
McAllen, TX
1932338_tn?1349223998
Blank
Luvtoski
Seattle