A novel refractive nomogram for the Custom-Q laser-assisted in-situ keratomileusis treatment of myopia

Background
To describe a new refractive nomogram to be used during the Custom-Q myopic laser-assisted in-situ keratomileusis (LASIK) ablation that seeks to minimize the postoperative spherical aberration (SA). This nomogram aims to avoid postoperative changes in target refraction that usually occur with customization of the value. This was a prospective controlled interventional case series.
Materials and methods
A total of 40 myopic patients (−1.00≤−8 D) were enrolled in this study. The right eyes of all patients were considered as the study group, where we targeted an ideal value of −0.45 during LASIK ablation. The corrected refractive error in the right eye was modified according to the new refractive nomogram to avoid the postoperative change in target refraction that occurs with the change in value. The left eyes of the same patients were considered as the control group with neither change in the value nor modification in the corrected refractive error. The classic outcome parameters such as visual acuity, cycloplegic refraction, as well as values and SAs were assessed and compared between the two groups preoperatively and at 1 month postoperatively. The LASIK machine involved in the treatment was The Allegretto Wave Eye-Q 400 Hz.
Results
There were no statistically significant differences (>0.05) between the two groups regarding the postoperative visual acuity and refraction at 1 month. On the contrary, there were statistically highly significant differences (<0.001) between the two groups regarding postoperative value and SA at 1 month postoperatively.
Conclusion
The new refractive nomogram used with the Q factor customized myopic LASIK ablation, which targets an ideal value to minimize the SA as much as possible, appears to be efficient in avoiding postoperative changes in target refraction that occur with customization of the value.