Abstract
Abstract: :
Purpose: Halos and starbursts around lights at night are a common complaint following LASIK. We created a device called the ‘Larson Glarometer' to quantify the starburst pattern. We used this device to directly compare starburst patterns resulting from laser in situ keratomileusis (LASIK) and laser epithelial keratomileusis (LASEK) status post treatment for myopia. Methods: Two groups of myopic patients were independently studied after refractive surgery. One group had LASIK, the other group had LASEK. An additional group of age-matched myopic controls were included in the study for comparison. LASIK procedure: A Nidek MK-2000 microkeratome with the ring at 8.5 mm was used to create a 160um corneal flap. Corneal ablation was then performed using the Visx S2 laser. LASEK procedure: 20% ethyl alcohol was placed within the corneal epithelial ring for twenty seconds. An intact epithelial flap was created allowing direct ablation to the corneal bed in accordance with the subject's myopic correction as per a standard nomogram. All eyes included in this study required no more than 6 diopters of myopic correction and had post-surgical UCVA of 20/25 or better and BCVA of 20/20 or better. Starburst measurements were recorded in uncorrected eyes a minimum of 3 months following refractive surgery. A ‘Larson Glarometer' was used to quantify starburst radius. This device, consisting of two low intensity (LED) light sources separated by four inches, was placed 8 feet from the subject in a totally dark room. After 15 seconds of dark adaptation, the subjects were asked to compare the appearance of the starburst radius to a key card depicting different degrees of starburst radii. Patient responses were recorded for each eye. Results: A total of 68 eyes were measured. The average starburst radius for the three separate groups were as follows: LASEK group 15.8 mm (n=26), LASIK group 20.3 mm (n=21), control group 5.5mm (n=21). Both the LASIK and LASEK groups showed a statistically significant increase in starburst (p=0.001 LASIK, p=0.005 LASEK) when compared to the control group. The difference in starburst radius between LASIK and LASEK groups was not found to be statistically significant (p= 0.255). Conclusion: Our study shows that starburst radius is increased following LASIK and LASEK. Although average starburst patterns were smaller in the LASEK group, our data was unable to show a statistically significant increase in the amount of starburst radius experienced in LASIK patients as compared to LASEK patients. A study using more subjects would be needed in order to establish if a statistically significant difference exists.
Keywords: refractive surgery: comparative studies • refractive surgery: LASIK • refractive surgery: other technologies