Abstract
Purpose: :
To compare clinical outcomes between LASEK and PRK in moderately myopic eyes (–4.00 D to –8.00 D) with regards to visually recovery time (number of days to 20/40 or better UCVA post operatively), corneal haze and post–operative pain.
Methods: :
Charts were reviewed for 50 PRK eyes and 50 LASEK (with alcohol) eyes, all performed by the same surgeon from 2002 to 2004. In both groups surgical corrections ranged from –4.00 D to –8.00 D. The average surgical correction was –5.75 D (SE) for PRK and –6.00 D for LASEK. Data for post–operative pain had been collected on post–op day 1, post–op day 4 and post–op day 7 using a standard 1 out of 10 pain scale. Only patients who did not report having any pain in either eye were recorded as negative for pain. Corneal haze was collected at post operative week one, 1 month, 3 months and 6 months out. Uncorrected visual acuity (UCVA) was recorded at post–op day 1, 4 and 7 and 1 month, 3 months and 6 months out. Visual recovery for the purpose of this study was pre–determined as 20/40 UCVA (Snellen). UCVA of 20/40 or better was considered positive for recovery while any recording worse than 20/40 was considered negative for recovery.
Results: :
Post operative pain between the two groups was similar. Differences were not statistically significant. Corneal haze was found in 6 out of 60 eyes in the PRK group and 16 out of 50 eyes in the LASEK group (P=0.0283). With regards to visual recovery, the PRK group had more eyes at 20/40 or better on post operative days 1 and 4 than the LASEK group (P=0.0011, P<0.0001). Final visual outcomes (UCVA) were similar between the two groups at 6 months.
Conclusions: :
Our results suggest that both types of refractive surgeries have demonstrated outstanding results with regard to UCVA at the 6 month endpoint for patients with moderate myopia. In fact, there was no statistically significant difference between the two groups with regards to UCVA at 1 month, 3 months and 6 months post operatively. But, since LASEK is a more complex and labor intensive procedure it makes sense to further scrutinize the theoretical benefits this surgery was poised to deliver such as decreased post–operative pain, less corneal haze and faster visual recovery times. In fact, our results showed the opposite to be true. Less haze and faster visual recovery times were seen in the PRK group and there was no significant differences seen with post–operative pain. These findings suggest that LASEK (with alcohol) albeit a successful refractive surgical procedure should not be considered superior to standard PRK for moderate myopes.
Keywords: refractive surgery: comparative studies • refractive surgery: PRK • refractive surgery: complications