would you please to explain me the diference between regular & irregular astigmatism?

the regular kind has a bow shape of symmetry. Irregular is asymetric and cant really be corrected by glasses. lasik, pinholes and RGP may reduce this. I see 20/30+ with best correction glasses but outdoors in bright sun my pupils become tiny and then I can see 20/20 which is just amazing. Everyone has high order abberivations, often lumped as irregular astigmistim thats why many people never normally see 20/20 I dont, my parents dont, no one in my family does uncorrected and only my bro and sister can be corrected to 20/20 but they are lucky.

A normal cornea is spherical, like the top of a ball. A cornea with regular astigmatism is elliptical in shape, like the back of a spoon.

Irregular astigmatism is a "catch all" phrase that can mean many different corneal shapes. It may be like many spoons stacked upon each other at different angles. It may mean that the surface is spherical, but irregular with dips and bumps.

Patients with irregular astigmatism often do well with rigid gas permeable (RGP) contact lenses. Irregular astigmatism tends to be very challenging for laser surgery correction and may have unpredictable results.

Glenn Hagele
http://www.USAEyes.org

I am not a doctor.