Dear Tim Harrington,
 
Thank you for your email. Normally, we recommend patients wearing rigid gas permeable contact lenses to refrain from wearing them for 2 weeks.  However, in your case, the ortho lenses reshape your cornea a great deal, and you would need a much longer time refraining from them.  I would adivse at least 1 month, but the longer the better.  The reason is we want your cornea to be in its most natural shape for accurate measurement.  How long will you be in Bangkok?
 
LASIK is able to correct nearsightedness combined with astigmatism up to -10.00 and farsightedness combined with astigmatism up to +4.00. However, the prescription alone does not determine whether you are a LASIK candidate.  Other factors such as corneal thickness, corneal curvature, eye pressure, and the health of your eyes all play a role in determining candidacy.
 
Warm regards,
TRSC International LASIK Center