Analysis of intraocular lens power calculation for cataract patients with high myopia and posterior scleral staphyloma

Abstract

Background The accurate calculation of intraocular lens (IOL) power is essential for attaining the desired refractive outcome after cataract surgery,especially for patients with high myopia and posterior scleral staphyloma.Objective This study was to evaluate the clinical feasibility of IOL Master compared with contact A-scan in cataract patients with high myopia and posterior scleral staphyloma,then compare the accuracy of different IOL power calculation formulas.Methods This was a prospective case control clinical research.Fourty-one eyes with age-related cataract of 28 patients underwent phacoemulsification with monofocal foldable IOL implantation in Tianjin Medical University Eye Hospital were involved,who were all high myopia with posterior scleral staphyloma.Preoperative measurement was measured with IOL Master as well as with contact A-scan and manual keratometry.IOL power was calculated according to the SRK-Ⅱ,SRK-T,Haigis,Hoffer Q,Holladay 1 formulas.The refractive outcome was followed-up 3 months after operation.Results The difference was significant between the 2 methods in axial length (AL) and anterior chamber depth (ACD) measurement (P =0.005,0.000) ; In corneal curvature measurement,there was no significant difference between them (P =0.398).When mean absolute refractive error (MAE) was divided by ±1.00 D,The SRK/T and Haigis formula performed better than other formulas measured by IOL Master;The Holladay 1,Hoffer Q and Haigis formula performed better than other formulas measured by contact A-scan combined with manual keratometry,respectively.Conclusions For cataract patients with high myopia and posterior scleral staphyloma,SRK/T and Haigis formula were recommended when employing IOL Master; whereas when using contact A-scan combined with manual keratometry,we prefer Holladay 1,Hoffer Q or Haigis formula. Key words: High myopia; Posterior scleral staphyloma; Axial length; IOL Master; Contact A-scan