Modern Orthokeratology
Reewat Jivanaromn M.D.
ABSTRACT Modern
orthokeratology is method of temporary correction of myopia which use rigid
contact lens. Since 1960s its main method of contact lens fitting is to
fit spheric or aspheric PMMA hard lens and rigid gas permeable lens flatter
than flattest corneal curvature. This can correct only 1-2 diopter of refraction
and it takes 6-24 months. Since 1990s, the lens design has been changed
to reverse geometric rigid gas permeable lens. Corneal topography is used
in monitoring changes of corneal curvature. The range of correction increases
to 5 diopter. The course of treatment is reduced to 2-6 months. At VISI
CORRECT CHIANGMAI, 90% of patients with 3 diopter or less myopia and 60%
of patients with 3-5 diopter myopia have good daytime visual acuity with
lens at night (55 eyes in 61 eyes, 16 in 28 eyes respectively). Main complications
are decentration of flattened area of cornea and inadequate correction of
myopia.
Thai
J Ophthalmol 1999 ; January-June 13(1) : 1-10. |