IOL power

INTRODUCTION: Dry eye can compromise corneal astigmatism measurement repeatability during preoperative cataract surgery examination. No previous studies have analyzed the effectiveness of long-acting 3% diquafosol sodium (LA-DQS) on astigmatism measurement repeatability. This research assessed the effect of LA-DQS on astigmatism measurement repeatability in preoperative patients with cataract and short tear break-up time (TBUT) type dry eyes in both eyes of the same patient. Correlations between repeatability and TBUT, corneal high-order aberrations (HOAs), and corneal astigmatism magnitude were also analyzed...

INTRODUCTION: This study aims to evaluate the accuracy of 12 different intraocular lens (IOL) power calculation formulas for post-radial keratotomy (RK) eyes. The investigation utilizes recent advances in topography/tomography devices and artificial intelligence (AI)-based calculators, comparing the results to those reported in current literature to assess the efficacy and predictability of IOL calculations for this patient group. METHODS: In this retrospective study, 37 eyes from 24 individuals with a history of RK who underwent cataract surgery at Hoopes Vision Center were analyzed...

OBJECTIVES: To compare central corneal topography (CT) obtained using the IOLMaster 700® biometer to corneal topography obtained using a Swept-Source OCT-based predicated topographer (PT), in candidates for toric intraocular lens (IOL) implantation. METHODS: A retrospective comparative study was conducted in consecutive patients undergoing a routine cataract surgery assessment with significant astigmatism on keratometry. Each patient was examined using both the IOLMaster 700® (Carl Zeiss Meditec, Jena, Germany) and the Anterion® (Heidelberg Engineering, Heidelberg, Germany) for routine preoperative measurements...

OBJECTIVE: To evaluate the effects of rigid corneal lenses (RCL) in patients with keratoconus, based on eccentricity. METHODS: Eighty-four eyes from 84 patients were included in this retrospective comparative study. Based on the median value of eccentricity difference between the cornea and back surface of the RCL, the patients were divided into groups 1 (<0.08) and 2 (≥0.08). Visual acuity, refractive index, and corneal topography indices were compared before and three months after lens use...

PURPOSE: To compare intraocular lens (IOL) power prediction accuracy of the Eyestar 900 (EyeS900) and the IOLMaster 700 (IOLM700) based on estimated and measured posterior corneal power DESIGN: Retrospective, inter-instrument reliability study METHODS: Setting: Institutional. PARTICIPANTS: 225 eyes of 225 cataract surgery patients. MEASUREMENTS: Patients underwent measurements by both devices preoperatively. MAIN OUTCOME MEASURES: Spherical Equivalent Prediction Error (SEQ-PE), spread of the SEQ-PE (Precision) and the absolute SEQ-PE (accuracy) of each device using Barrett Universal II (BUII) formula with either estimated posterior keratometry (E-PK) or measured posterior keratometry (M-PK)...

It is important to be able to measure the range of clear focus in clinical practice to advise on presbyopia correction techniques and to optimise the correction power. Both subjective and objective techniques are necessary: subjective techniques (such as patient reported outcome questionnaires and defocus curves) assess the impact of presbyopia on a patient and how the combination of residual objective accommodation and their natural DoF work for them; objective techniques (such as autorefraction, corneal topography and lens imaging) allow the clinician to understand how well a technique is working optically and whether it is the right choice or how adjustments can be made to optimise performance...

PURPOSE: To present a reproducible method to calculate the toricity needed at the intraocular lens (IOL) plane with toric phakic IOLs (ICL, Staar Surgical) and compare its results with those obtained with the online calculator provided by the manufacturer. DESIGN: Retrospective case series. SETTING: Private practice, Buenos Aires, Argentina. METHODS: The formula originally described by Holladay to calculate the IOL power in phakic eyes was used to calculate the required spherical power along the less refractive meridian and along the more refractive meridian...

PURPOSE: This study is to evaluate the optical characteristics of a non-diffractive wavefront-shaping intraocular lens which incorporates surface refractive modifications for shaping the wavefront in order to achieve extended depth of focus (EDoF) and to assess whether the nominal power of this IOL influences the attainable add power. METHODS: A commercially available optical bench NIMO TR1504 device (LAMBDA-X, Nivelles, Belgium) was employed to obtain full optical characterization of three non-diffractive EDoF intraocular lenses with + 10 D, + 20 D, and + 30 D powers...

PURPOSE: To compare simulated keratometry (SimK) and total corneal power (TCP) in keratoconic eyes, to determine whether the differences are systematic and predictable and to evaluate an adjusted TCP-based formula for intraocular lens (IOL) power calculation. METHODS: In a consecutive series of keratoconic eyes, measurements of SimK, TCP, posterior keratometry, and anterior and posterior corneal asphericities (Q-values) were retrospectively collected. The difference between SimK and TCP was linearly correlated to the biometric parameters...

OBJECTIVES: To evaluate the effect of maternal age and body mass index (BMI) on oral misoprostol induction of labor for late-term pregnancies. DESIGN: Retrospective cross-sectional study (ClinicalTrial iD: NCT06184139), including only late-term pregnancies in healthy nulliparous women and single cephalic fetus with normal birthweight. Specify the type of study (randomized, prospective cohort, case-control, other) and include the number of study subjects (cases/controls), treatment type and duration, sampling procedures if applicable...

PURPOSE: To compare the accuracy of nine conventional and newer-generation formulae in calculating intraocular lens power in eyes with axial myopia. SETTING: Tertiary eye care center, Bengaluru, India. DESIGN: Retrospective cross-sectional, comparative study conducted in India. METHODS: Patients undergoing uneventful phacoemulsification in eyes with axial length >26 mm were included. Preoperative biometry was done using Lenstar LS 900 (Haag-Streit AG, Switzerland)...

The possible future emergence of new SARS-CoV-2 virus variants pushes the development of new chemoprophylaxis protocols complementary to the unspecific and specific immune-prophylaxis measures currently used. The SARS-CoV-2 virus is particularly sensitive to oxidation, due to the relevant positive electrical charge of its spike protein used as a ligand for target cells. The present study evaluated the safety and efficacy of a new oxidant preparation, liquid hyperoxygen (IOL), to neutralize the SARS-CoV-2 virus...

PURPOSE: This study aimed to evaluate and optimize intraocular lens (IOL) power selection for cataract patients with high axial myopia receiving trifocal IOLs. DESIGN: A multi-center, retrospective observational case series was conducted. Patients having an axial length ≥26 mm and undergoing cataract surgery with trifocal IOL implanted were studied. METHODS: Preoperative biometric and postoperative outcome data from 139 eyes were collected to train and test various machine learning (ML) models (support vector machine, linear regression, and stacking regressor) using five-fold cross-validation...

OBJECTIVE: Aim of this study was to use a combination of partial least squares regression and a machine learning approach to predict IOL tilt using pre-operative biometry data. SETTING: Patients scheduled for cataract surgery at the Kepler University Clinic Linz. DESIGN: Prospective single center study. METHODS: Optical coherence tomography, autorefraction and subjective refraction was performed at baseline and 8 weeks after cataract surgery...

PURPOSE: To evaluate the refractive prediction error in flanged intrascleral intraocular lens (IOL) fixation using the SRK/T formula and compare the axial length using a single IOL. METHODS: Seventy-six eyes from 70 patients (45 males and 25 females) were included in this study. The mean age at the time of surgery was 73.4 ±12.3 years. The patients underwent flanged IOL fixation using a PN6A (Kowa). All surgeries were performed by two surgeons (Y. K. and T...

INTRODUCTION: This study aimed to determine the interchangeability of bilateral anterior chamber depth (ACD) in intraocular lens (IOL) power calculations for cataractous eyes and refractive outcomes using the unaffected fellow-eye ACD in lens subluxation. METHODS: The predicted postoperative spherical equivalent (SE) calculated using the Kane formula with and without fellow-eye ACD in 202 cataract patients was compared. Refractive outcomes of the newer formulas (the Kane, Barrett Universal II (BUII), and Pearl-DGS formulas) with affected-eye ACD and with unaffected fellow-eye ACD were compared in 33 eyes with lens subluxation (the affected eye) undergoing in-the-bag IOL implantation...

PURPOSE: To compare the refractive accuracy of legacy and new no-history formulas in eyes with previous myopic laser vision correction (M-LVC). DESIGN: Retrospective cohort study. METHODS: Setting: Two academic centers Study Population: 576 eyes (400 patients) with previous M-LVC that underwent cataract surgery between 2019-2023. A SS-OCT biometer was used to obtain biometric measurements, including standard (K), posterior (PK), and total keratometry values (TK)...

INTRODUCTION: The aim of this work is to evaluate the accuracy of the Barrett Universal II (BU II), Emmetropia verifying optical (EVO) 2.0, Haigis, Hoffer Q, Hoffer QST (Savini/Taroni) (HQST), Holladay 1, Kane, Ladas Super, Sanders-Retzlaff-Kraff/theoretical (SRK/T), and T2 intraocular lens (IOL) power formulas for calculating spherical equivalent (SE) of toric IOL. METHODS: This study enrolled consecutive patients who underwent phacoemulsification and toric IOL implantation at the Eye Hospital of Wenzhou Medical University in Hangzhou from 2015 to 2022...

PURPOSE: To investigate surrogate optimisation (SO) as a modern, purely data-driven, nonlinear adaptive iterative strategy for lens formula constant optimisation in intraocular lens power calculation. METHODS: A SO algorithm was implemented for optimising the root mean squared formula prediction error (rmsPE, defined as predicted refraction minus achieved refraction) for the SRKT, Hoffer Q, Holladay, Haigis and Castrop formulae in a dataset of N = 888 cataractous eyes with implantation of the Hoya Vivinex hydrophobic acrylic aspheric lens...

BACKGROUND: This study evaluates the impact of corneal power on the accuracy of 14 newer intraocular lens (IOL) calculation formulas in cataract surgery. The aim is to assess how these formulas perform across different corneal curvature ranges, thereby guiding more precise IOL selection. METHODS: In this retrospective case series, 336 eyes from 336 patients who underwent cataract surgery were studied. The cohort was divided into three groups according to preoperative corneal power...