The Research On The Effectiveness Of Wavefront-aberration Guided SBK On Refractive Error

Objective: To observe the pre and post operation visual acuity, characteristics of corneal topography ,the parameters of wave-front aberrations, as well as the complications and their possible affecting factors .To further investigate new solution of improving postoperative visual quality in an all around way for patients with refractive errors.Methods: To have a retrospective analysis of pre- and post operative clinical data of 16 cases (32 eyes) that had gone through wavefront-guided SBK in their treatment of refraction error. All patients were required to take preoperative and postoperative examinations including UCVA, BCVA, IOP measurements, refraction status, corneal thickness, corneal topographic tests, namely corneal curvature ( Km ) and posterior corneal surface height, WaveScan aberrometer test and so on. An assessment of the treatment effectiveness of wavefront-guided SBK was made in a relatively conclusive way.Results: There is no presence of severe postoperative complications . 31.25% patients complained about the existence of halo .1 patient expressed glare. All but one patient (2eyes) have obtain vision acuity of 1.0 or more just 1month after operation and later from then on. BCVA is improved for some patients. BCVA improve one line in 14 eyes and 2 lines in 4 myopia eyes. Postoperative corneal curvature and corneal thickness decreased significantly; There is no increase of posterior corneal surface height ,without any statistical significance. RMS3, RMS4, RMS5, RMS6 have all increased, with RMScoma as well as RMSsphere making the greatest contribution to the rising HOA(P<0.05), but no obvious changes for trefoil.Conclusions:1 UCBA after wavefront- guided SBK is predicative within expected range of refraction.2 BCVA is improved in parts of the patients ,especially those with high myopia.3 There is no sign and evidence of rising of corneal posterior surface height and presence of corneal ectasia, further improving the safety of the operation.4 Postoperative high order aberrations have all increased obviously, with coma and sphere RMS(root mean square) taking the greatest share with statistical significance, without too much influence of the visual quality after operation.