Astigmatism axis different between prescriptions

glider3560

Before I query with the optician this week, can anyone tell me if they also think this is a bit odd.

I have astigmatism and have an axis measurement on my prescription.

2014:
Left 180.0
Right 180.0

2017:
Left 175.0
Right 5.0

It seems odd that the shape of my right eye would have changed over a three year period! Does anyone else think this is also a typo on the right eye?

boliston

5 degrees is the smallest change i think (a minute on a clock face is 6 degrees)

theoretica

You seem to be thinking that 5 degrees is a whole 175 degrees away from 180 - but it isn't - it is only 5 degrees away, because 180 = 0. The axis goes all the way through the centre point and out the other side.

[Deleted User]

Hi,

Axis. This describes the lens meridian that contains no cylinder power to correct astigmatism. The axis is defined with a number from 1 to 180. The number 90 corresponds to the vertical meridian of the eye, and the number 180 corresponds to the horizontal meridian.

glider3560

Thanks everyone. That's put my mind at rest!

The optician seemed very rushed, so making a typo could have easily been a possibility. But clearly, that's not the casw.