Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
SIA: Surgically induced astigmatism; TIA: Target induced astigmatism; Abs.: Absolute; Arith.: Arithmetic; Ax: Axis; CC/Wise: Counterclockwise; C/Wise: Clockwise.
