Comparison of measurements with optical biometry and ultrasound biometry in different types of cataracts in terms of refractive results

Objective: To compare the success of Aladdin optical biometry and ultrasound biometry in achieving the target refraction in different types of cataract in terms of the consistency and reliability in the early postoperative period. Materials-Methods: Ninety-six eyes of 24 nuclear cataracts (NC), 24 posterior subcapsular cataract (PSC), 24 cortical cataract (CC) and 24 mixed cataract (MC) patients aged between 50-80 years, who underwent uncomplicated phacoemulsification surgery due to the senile cataract in the Ophthalmology Department of Tokat Gaziosmanpaşa University Faculty of Medicine, between 15th June 2021 and 15th Nov 2021 and underwent intracapsular one-piece monofocal acrylic hydrophobic lens implantation. Following a general ophthalmological examination, optical biometry (Aladdin, Topcon, Tokyo) and A-scan ultrasound biometry (Echoscan US-4000, Nidek) were performed and biometric measurements were recorded in all patients. Postoperative emmetropization was targeted and the patients were examined on the 1st day, 7th day, 1st month and 3rd month of operation. Results: The mean of absolute refractive errors calculated by using Aladdin optical biometry were found to be significantly lower than values calculated by using ultrasonic biometry in all examinations (p<0.001). Using Aladdin biometry, the ratio of eyes with resulting refraction in the range of ±0.50 D and ±1.00 D was found to be 60.4% and 91.7%, respectively. Using ultrasound biometry, these rates were found to be 47.9% and 67.7%, respectively. The rate of Aladdin biometry reaching to the range of ±0.50 D and ±1.00 D was found to be significantly superior to those of ultrasound biometry (p:0.003 and p:0.007). Aladdin biometry resulted significantly better refraction outcomes in NC and MC types (p<0.05). Conclusions: Our study is the first in the literature to compare target refraction outcomes in optical and ultrasound biometry for different types of cataracts. According to our data, the optical biometry is more successful in achieving emmetropization than ultrasound biometry. Therefore, using optical biometry seems more appropriate to calculate intraocular lens power before cataract surgery. Keywords: Intraocular lens, cataract, optical biometry, ultrasound