At age 10 years his spectacle refraction
was R -2.00/-0.75 x 90 and L -2.50/-1.25 x 90.
(1) The effective treatment calculated at the corneal plane (taking into account the preoperative and postoperative spectacle refraction
, converted at the corneal plane with the formula  SE corneal plane = SE spectacle plane/[1 - (0.012 x SE spectacle plane)]) was added to the Kpost.
If the lens sits in a stable position then a compensation can be made to the lens order to account for this clockwise rotation and 30[degrees] should be added to the spectacle refraction
Simply enter the spectacle refraction
(without BVD) for right and left eyes, including reading add and dominant eye, and the app gives an initial lens power recommendation.
Users select the lens type they want, enter the spectacle refraction
and the recommended trial lens power is shown in a bar below.
SAUFLON HAS launched an online calculator which is designed to assist practitioners in accurate contact lens selection for its core or XR toric prescriptions by simply inputting spectacle refraction
and back vertex distance values.
Most laboratories will need to be provided with spectacle refraction, along with the back vertex distance (BVD), as well as the K readings (to two decimal places).
Terminology Explanation Spectacle refraction The spherical and cylindrical combination required, at a stated vertex distance, to correct the patient's ametropia Ocular refraction The spectacle refraction adjusted by compensating for the back vertex distance (BVD) Spectacle astigmatism Can occur either from corneal and/or lenticular astigmatism.
A restriction will also apply if the refractive correction exceeds -8.00DS (-8.75DS spectacle refraction
if contact lenses are worn), and the uncorrected vision must be at least 6/20 (0.3 decimal).
A 54-year-old patient has the spectacle refraction shown in Image C.
If the patient in Question 5 and with the spectacle refraction shown in Image C decides to opt for monovision correction, which of the following would be the MOST appropriate lens powers to select initially?
RGP fittings are usually done from a trial set or ordering empirically from the "K" readings (keratometer reading) along with the spectacle refraction
and back vertex distance (BVD).