Here you can find lots of optical and lasik on the answers, a better understanding of your eyes.
Are my spectacle prescriptions similar?
i hold a prescription from 1999 which is right: sph +1.25 cyl -2.50 axis 5 left sph +0.50 cyl -2.25 axis 170 however a prescription from this year is as follows right sph -0.75 cyl-1.00 axis 5 moved out -0.75 cyl -0.50 axis 175 as you can can see there are different measures but would it be correct to wok the sum out of the cyl and sph to establish the power of correction?
They are not similar. In 1999 you be hyperopic with significant astigmatism, in a minute you are myopic with mild astigatism. Are you an elder person developing cataract?, that species of change is not unusual when developing cataract
Not sure what you be going to by "sum" and "power of correction". You can calculate equivalent sphere power.
L: -1.00 no. those are not all that similar. one is "mixed" astigmatism and the other is "compound myopic" astigmatism. pretty big difference.
The answers post by the user, for information lone, LasikAnswer.com does not guarantee the right and should not be considered medical advice, diagnosis or treatment recommendation.