What is my spherical contact lens prescription based on my toric lens prescripti!
Question: What is my spherical contact lens prescription based on my toric lens prescription?
LEFT EYE
bc = 8.8
dia = 14.4
pwr = -7.00 / -0.75 x 070
RIGHT EYE
bc = 8.8
dia = 14.4
pwr = -7.00 / -0.75 x 130
Also, it seems the base curve on the circle lenses are 8.6. Will this be alright? The diameters of the circle lenses are the same as my current prescription.
And, what does the "x 070" and "x 130" mean after the astigmatism numbers?
Thank you
Answers:
Best Answer - Chosen by Voters
The -7.00 is the sphere part of your prescription; the -0.75 is the cylinder part and the last numbers are the axis for the cylinder part (tell how it needs to be oriented with respect to yourt eyes). Essentially, your eyes need a -7.00 in one direction and 90 degrees from that, they need -7.75. This is because your corneas are slightly out of round (like a slight football shape instead of a perfect, little, spherical dome).
Anyway if you want the closest sphere-only prescription, you need to split the difference between the 2 numbers I mentioned. Technically, that would be a -7.375 but, they don't make that strength, they only go in increments of 0.25, so try a -7.25. This will leave you 0.25 over-corrected in one axis and 0.50 under-corrected in the other, so, your vision is not going to be perfect. You are also getting a different base curve. With contact lenses, a slight change can make a big difference. Sometimes, just changing the brand (all the numbers being exactly the same) makes a difference of being able to wear them or not. So what I am saying is: I can't guarantee they will work for you.
It's kind of surprising to see that you have been fit with toric lenses with that small amount of astigmatism in comparison to the high sphere power.
In your case, a spherical equivalent would be - 7.25 , but that probably isn't made, so stick with - 7.00 , you won't see any difference.
The 70 and 130 is the axis, which is the meridian that your astigmatism correction is placed at in your lenses. The Axis pertains only to the astigmatism correction.
Will an 8.6 work?...we have no idea if they will work or not for you , but not just because of the 8.8 to 8.6 difference. The fact they are different lenses , different material, ect...means it is just a wild guess as to whether they will fit you well or not. No one can tell in advance how any different brand lenses will fit on someone. That's why we do trial fittings when the patient is in the office.
Optician