Comparison of Femtosecond laser and microkeratome for corneal flap making in sub-Bowman's keratomileusis

Objective To compare and analyze the effectiveness,predictability,safety and stability of sub-Bowman's keratomileusis(SBK)with corneal flap created by Femtosecond laser and microkeratome respectively.Methods We reviewed 1000 patients(2000 eyes)treated by SBK to correct myopia[sph.:-1.0～9.75 diopter(D),cylinder: 0～2.75 D] in out-patient department of Kangqiao Hospital of Chengdu from Jan.2010 to Apr.2010.The patients were divided into Femtosecond laser group(1000 eyes)and microkeratome group(1000 eyes).Uncorrected visual acuity(UCVA),diopter,postoperative best corrected visual acuity(BCVA),lost of BCVA,refractive stability and complications of the two groups after operation(1 day,1 week,1 month,3 month,6 month)were compared with those before operation.Results Both two operations had good predictability,but the Femtosecond laser group had better manifestation 1 day after operation.UCVA of 95.5%of the cases in Femtosecond laser group reached or exceeded preoperative BCVA 1 day after operation,while 91.2%of the cases in microkeratome group did.There was significant difference between the two groups(P0.05).But there were no significant differences between the two groups in other postoperative visits(1 week,1 month,3 months,and 6 months).About 21.5%of the cases in Femtosecond laser group could see one more line on eye chart 6 months after operation,while 15%of the cases in microkeratome group could.There was significant difference between the two groups(P0.05).No patient in Femtosecond laser group lost more than two lines(eye chart)of vision 6 months after operation,while in microkeratome group,the number was 3 cases.Conclusions SBK with corneal flap created by Femtosecond laser is safety and has a quick and good postoperative visual acuity.We still need long-term observation about the stability of visual acuity and changes in corneal biomechanics.