 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Medical Forum / General / Vision / May 2007How is a "zero" astigmatism written?
My wife wears non-toric contact lenses. Her RX is: -6.00 -1.00 x087 -6.00 -0.75 x106 They did tell her that the astigmatism in each eye is small enough that she does not need toric lenses. So, would a total lack of astigmatism look like: -6.00 -1.00 x090 -6.00 -1.00 x090 Or: -6.00 plano x090 -6.00 plano x090 Or something else? I understand that there are many ways to write the same thing, but I am trying to figure out how far she if from not have any astigmatism.  SignatureDoug Herr doug*at*wombatz*dot*com > I understand that there are many ways to write the same thing, but I am > trying to figure out how far she if from not have any astigmatism. When the cylinder (astigmatism, second number) is zero, it isn't written, and without cylinder the axis is meaningless so it isn't written either. When a prescription is written "-6.00" and nothing more, we assume there is no astigmatism. More properly, it's written "-6.00 DS" (Diopter Sphere) to imply there is no DC (Diopter Cylinder). Machine printouts sometimes report cylinder as "0.00." -MT >> I understand that there are many ways to write the same thing, but I am >> trying to figure out how far she if from not have any astigmatism. [quoted text clipped - 4 lines] >When a prescription is written "-6.00" and nothing more, we assume there is >no astigmatism. I like to see some notation that verifies that there's no cylinder, especially when their old glasses have a cylinder power. If it's a .25 or .50, then it's safe bet there's no cylinder, but when the old cylinder is .75 or higher, I call to make sure it wasn't omitted. >More properly, it's written "-6.00 DS" (Diopter Sphere) to imply there is no >DC (Diopter Cylinder). Typically, I see -600 sph, with the decimal point inferred, although I've seen 25 when they meant to write 250. It's a good idea, if we are not using decimal points, to put a zero before the quarter, half, and three quarter powers so they read 025 etc. And for god's sake don't ever use a degree sign after the cylinder axis! Regards Robert Martellaro ~~~~~~~~~~~~~~~~~~ Optician/Owner Roberts Optical Wauwatosa Wi. ~~~~~~~~~~~~~~~~~~ "Science is a way of trying not to fool yourself." - Richard Feynman > My wife wears non-toric contact lenses. > [quoted text clipped - 24 lines] > Doug Herr > doug*at*wombatz*dot*com it commonly would be written as: -6.00 -or- -6.00 sph -or- -6.00 DS yes-- she has a small amount of astigmatism. many people with less than -1.00 diopters of astigmatism usually report their vision to be very clear with non-toric lenses. from what you have written your wife has -1.00 diopters of astigmatism in her right eye (OD) and -0.75 diopters of astigmatism in her left eye (OS). in my practice I would generally trial such a patient with non-toric (spherical) lenses first. |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.