Relationship between the contrast sensitivity and HOA during the first year after PRK
| Authors | |
|---|---|
| Year of publication | 2008 |
| Type | Article in Proceedings |
| Conference | ESCRS Congres abstract |
| MU Faculty or unit | |
| Citation | |
| Field | ORL, ophthalmology, stomatology |
| Keywords | HOS; contrast sensitivity, optical aberration |
| Description | To assess aberration and contrast sensitivity (CS) changes during 12 months after PRK. To investigate relationship between aberrations and CS. Setting: The prospective nonrandomized study. Method: Seventy-eight eyes of 41 consecutive subjects (19 males and 22 females; mean age 28.2 years) were treated with PRK with standard ablation profile (Technolas 217 excimer laser) between Nov-2006 and Nov-2007. The preoperative spherical refraction was -2.9 diopters and cylinder -0.4 diopters. All enrolled eyes underwent assessment using the Hartmann-Shack wavefront aberrometer (Zyoptix, Bauch Lomb) and CS was assessed by CSV-1000E (VectorVision) under mesopic conditions. The assessments were carried out preoperatively and 1, 3, 6 and 12 months after PRK using 6.0 wavefront aperture diameter. The total root-mean-square (RMS) value (TOA), the higher-order RMS (HOA) and the 4th-order RMS (SA) were compared with the values of CS. The statistical analyses used Wilcoxon and Mann-Withney U tests. Conclusions: Although PRK leads to increases of HOA and SA, it only rarely negatively affects the final mesopic CS of the patients. However all cases with below normal CS after the PRK were associated with significantly higher values of TOA and SA and were accompanied by slightly lower uncorrected visual acuity. |