Intraocular lens Master optical biometry vs conventional ultrasonic biometry in intraocular lens power calculations in highly myopic vs emmetropic eyes

Abstract

Aim The aim was to compare between the preoperative intraocular lens (IOL) power calculations accuracy measured by IOL Master vs applanation ultrasonic biometry in highly myopic and emmetropic eyes regarding postoperative refractive error. Patients and methods The IOL powers of 32 eyes of 32 patients prepared for phacoemulsification with IOL implantation were calculated preoperatively by IOL Master and A-scan. Postoperative refractive outcomes and spherical equivalent were compared with the predicted refractive error of each method. Results The mean±SD age of the 32 recruited patients was 53.91±10.21 years. The mean axial length (AXL) measured by IOL Master was higher (25.8±2.65 mm) than that with A-scan (25.46±3.43 mm), with a mean difference of 0.34±1.04 mm (P=0.2112). The mean predicted IOL power was 13.50±7.80 D with IOL Master vs 13.63±9.05 D with A-scan (P=0.930). However, no statistically significant difference was found regarding average K readings and predicted postoperative refraction (P=0.05 and 0.564, respectively). Further subgroup analysis revealed a statistically significant difference in AXL between both devices only in emmetropic group, with mean difference of 0.99±0.485 mm (P=0.00068). The mean absolute errors measured by IOL Master was 0.19±0.1417, whereas that of A-scan was 0.561±0.623. The mean difference between the two methods was −0.371 (P=0.0385), which was statistically significant. Discussion and conclusion The IOL Master AXL measurements were accurate, allowing more accurate calculation of the (IOL) power. It is user friendly, fast, with no contact with the corneal surface and with no possibility of damage to the surface or transmitting a disease.

Keywords

• a-scan
• axial length
• biometry
• cataract
• intraocular lens master
• phacoemulsification