Changes of ocular higher order aberration in on- and off-eye of rigid gas permeable contact lenses.
OBJECTIVE
To investigate ocular higher order aberration (HOA) changes caused by rigid gas permeable (RGP) contact lens (CL) wear.


METHODS
Twenty-two eyes of 22 myopic patients and 14 eyes of 14 keratoconic patients who were fitted with an RGP CL were enrolled to examine ocular HOAs using a Hartmann-Shack wavefront sensor before and after RGP wear. Root mean square (RMS) values and Zernike coefficients in RGP-on and RGP-off eyes were compared for both myopic and keratoconic eyes, or between patient groups divided according to their prefitted total HOA value (RMS<0.33 microm or>or=0.33 microm in myopic eyes and RMS<0.46 microm or>or=0.46 microm in keratoconic eyes). All HOA values were recomputed for a 4-mm pupil for comparison purposes.


RESULTS
In keratoconic eyes, RGP CL changed the direction of vertical coma from -0.185 to 0.134 microm (p=0.024). In the low HOA myopic group, total HOA increased from 0.23 to 0.35 microm (p=0.006) by RGP CL wear, mainly due to increased coma aberration from 0.0951 to 0.2146 microm (p=0.006). The direction of vertical coma changed from the inferior to superior cornea in the low HOA group (p=0.020). In the high HOA keratoconic group, total HOA decreased from 0.54 to 0.36 microm (p=0.049), and the direction of the vertical coma changed from the inferior to superior cornea (p=0.049).


CONCLUSIONS
RGP CL wear may enhance or reduce HOA based on original existing ocular aberration mainly through directional changes in vertical coma.
Choi
Jin
J
Department of Ophthalmology, Seoul National University College of Medicine, and Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, South Korea.
Wee
Won Ryang
WR
Lee
Jin Hak
JH
Kim
Mee Kum
MK
D000293:Adolescent; D000328:Adult; D003262:Contact Lenses, Extended-Wear; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology* / Q000628:therapy; D008027:Light; D009216:Myopia / Q000503:physiopathology* / Q000628:therapy; D012029:Refraction, Ocular / Q000502:physiology*; D012189:Retrospective Studies