Clinical Study Of Femtosecond Laser-assisted Intrastromal Keratoplasty(FS-LIKE) In Correcting Hyperopia And Astigmatism

Objective:To explore the early clinical effects of femtosecond laser-assisted intrastromal keratoplasty(FS-LIKE)in the treatment of hyperopia and astigmatism.Methods:A prospective disease analysis study was used to select 10 patients with moderate to high hyperopia who met surgical requirements and met the surgical requirements from December 2019 to December 2020 in the Department of Refraction of the Affiliated Eye Hospital of Nanchang University,including 6 males and 6 females 4 Eyes,aged 18-36 years,average(25.30±6.25)years old,underwent femtosecond laser-assisted intrastromal keratoplasty(FS-LIKE),donor corneas were taken from the same period Small incision femtosecond laser lens extraction(Small incision lenticule extraction,SMILE)myopia patients.Follow-up for 6 months after surgery,observation of uncorrected distance visual acuity(UDVA),uncorrected near visual acuity(UNVA),and best corrected visual acuity at 1d,1w,1m,3m,and 6m after surgery(Best corrected distance visual acuity,BCDVA),equivalent spherical lens power(Spherical equivalent refraction,SE),cylinder refraction(Cylinder refraction,C)and other visual acuity and refractive power,and use slit lamp,tonometer,corneal topography,Optical coherence tomography(OCT),to observe intraocular pressure(Intraocular pressure,IOP),corneal morphology,steep axial curvature of the anterior cornea K1,flat axial curvature of the anterior surface K2,average front and rear surfaces Curvature(Mean meridian keratometry,Km)posterior surface,central corneal thickness(Central corneal thickness,CCT),etc.,to evaluate femtosecond laser-assisted intrastromal keratoplasty for the treatment of hyperopia and Early clinical efficacy of astigmatism.The data used single factor repeated measures analysis of variance,and set P<0.05 as the difference was statistically significant.Result:All patients had successful operation and completed follow-up.UDVA and UNVA were significantly improved at all time points after surgery(both P<0.05).Except for 1 eye with poor BCDVA at the last follow-up postoperatively,the remaining operative eyes were improved or remained the same.At a time point after surgery,SE was significantly improved((F=46.055,P < 0.05)).There was mild overcorrection in the early postoperative period,and no significant refractive regression was seen.Except for 1 eye which was an early stage of operation,the cylindrical power statistics of 1d,1w,1m,3m and 6m after surgery were(-0.75 ±1.45)D,(-0.69 ± 0.39)D,(-0.69 ± 0.45)D,(-0.64 ± 0.45)D,(-0.64 ± 0.30)D,significantly improved compared with(-1.61 ± 1.12)D before surgery(F=9.544,P=0.007).Slit lamp microscopy results showed that the cornea was mildly edema in the early postoperative period,the graft was in place,transparent,and the boundary was clear.With time,the corneal edema gradually subsided and became clear and transparent.The graft gradually merged with the surrounding tissues,and the lens boundary was blurred at the last follow-up after surgery.It’s hard to tell.OCT results showed that the corneal surface was smooth,the corneal flap was repositioned well,the lens implant was in place,and the lens boundary gradually merged with the surrounding tissues over time.The results of corneal topography showed that the CCT increased significantly after the operation,the anterior corneal K1,K2,Km increased significantly,and the center became steeper(all P values <0.05);the Km of the posterior corneal surface did not change significantly compared with the preoperative Km(F=0.148,P=0.728)).There was no significant difference in IOP at each time point after operation compared with that before operation(F=1.303,P=0.296).Conclusion:Femtosecond laser-assisted intrastromal keratoplasty in the treatment of hyperopia and astigmatism has a safe,effective and stable early effect.This type of surgery has a short learning curve at the beginning of school,and it has faster operation,accurate positioning,safe and reversible.The advantages of the corneal stroma can be used to correct the gap in the treatment of hyperopic astigmatism,providing a new surgical options for patients with hyperopic astigmatism.