Comparison of intraocular lens power calculation using a standard ultrasonic biometer and a new optical biometer

Abstract

AIM:To compare the intraocular lens(IOL)power calculations and refractive outcomes obtained with a new optical biometer and standard ultrasonic biometer in phacoemulsification surgery.METHODS:Thirty-seven eyes of 37 cataract patients who underwent phacoemulsification with IOL implantation were included in this prospective comparative study. The same operator performed biometer measurements in eyes with cataract using a new optical biometer(Aladdin)and a standard ultrasonic biometer(Sonomed AB 5500). Biometric parameters; axial length(AL), keratometric(K)readings, anterior chamber depth(ACD)and IOL power obtained by two devices were recorded. Postoperative actual refractive errors and errors predicted by two devices according to SRK/T formula were analyzed. The mean estimation error(EE), mean absolute estimation error(AEE)and the biometric parameters obtained by two biometers were compared.RESULTS:The AL measured by Aladdin(23.45±0.73 mm)was significantly longer than AL by ultrasonic biometer(23.2±0.75 mm)(P=0.01). The mean EE and AEE values obtained by Aladdin were significantly smaller than the values by ultrasonic biometer(P=0.0006 and 0.03 respectively). The higher percentage of eyes within ±0.5 and ±1.00 D of target refraction was also found by using Aladdin(67% and 97%).CONCLUSION:The Aladdin optical biometer showed better accuracy and yielded better refractive outcomes compared with ultrasonic biometer.

Keywords

• Aladdin optical biometer
• ultrasonic biometer
• axial length
• intraocular lens power calculation
• postoperative refractive error