_____________________________________________________________________________________________________ *Corresponding author; Journal of Advances in Medicine and Medical Research 34(21): 391-397, 2022; Article no.JAMMR.91031 ISSN: 2456-8899 (Past name: British Journal of Medicine and Medical Research, Past ISSN: 2231-0614, NLM ID: 101570965) Accuracy of the Postoperative Refractive Prediction in Optical Biometry Versus Ultrasound Biometry in Preoperative Intraocular Lens Power Calculation Samar Saad Badr a* , Ahmed Fekry Al Maria a , Hisham Adel Hasby a and Mohamed Abd El-fattah Shaheen a a Department of Ophthalmology, Faculty of Medicine, Tanta University, Tanta, Egypt. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/JAMMR/2022/v34i2131557 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/91031 Received 21 June 2022 Accepted 25 August 2022 Published 29 August 2022 ABSTRACT Background: Contact A-scan ultrasonic biometry is the most frequently utilized technique for determining axial length (AXL). Optical biometry is a technique that utilises partial coherence interferometry to determine ocular biometry parameters. The aim of this research was to compare the efficacy in estimating postoperative refraction by measuring intraocular lens (IOL) power by the optical biometry (IOL Master) and contact A-scan ultrasound plus Bausch & Lomb (B&L) keratometry after phacoemulsification surgery. Methods: This prospective, comparative, interventional and randomized study involved 40 eyes with uneventful phacoemulsification surgery and in the bag IOL of adult patients with cataract. Subjects were allocated into 2 equal groups: group A: implanted the IOL power estimated by the automated method and group B: implanted the IOL power estimated by the manual method. All patients were subjected to complete ophthalmic examination, best-corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), snellen visual acuity, cycloplegics refraction and slit lamp examination. Results: The mean predicted error of IOLM was -0.108 ± 0.462 (P= 0.311) in group A and was 0.053 ±1.092 (P= 0.830) in group B, and the Predicted error of A scan was -0.661 ± 0.686 (P= <0.001) in group A which is statistically significant and -0.340 ± 0.972 (P= <0.134) in group B. IOL power measured by IOLM in group A was significantly lower than IOL power measured by A-Scan Original Research Article