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Intraocular lens power calculation after radial keratotomy and LASIK - A case report
Chun-Fu Liu1,2,3, Chi-Chin Sun1,2, Yun-Hsuan Lin1,2
1Department of Ophthalmology, Keelung Chang Gung Memorial Hospital, No.222, Maijin Rd., Keelung City, 204, Taiwan.
Purpose:
To report a challenging intraocular lens (IOL) power calculation case who received both radial keratotomy (RK) and laser-assisted in situ keratomileusis (LASIK).
Observations:
A 51-year-old man had received refractive surgery with RK and later enhanced by LASIK more than 20 years ago. He developed severe cataract in left eye with best-corrected visual acuity of 20/100. The IOL power calculation was made using several methods available at the American Society of Cataract and Refractive Surgery (ASCRS) online calculator, including IOL calculation formulas for post-LASIK condition (Shammas, Haigis-L, Barrett True K no history, and Potvin-Hill Pentacam) and formulas for post-RK condition (Double K-modified Holladay 1 based on Oculus Pentacam and IOL Master, and Barrett True K). Haigis-L, Shammas and Barrett true K no history were found to be most accurate in predicting IOL power.
Conclusions:
Haigis-L, Shammas and Barrett true K no history are reliable formulas for IOL power calculation in patients who received both RK and LASIK.
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