Refractive Outcomes Utilizing Two SS-OCT Biometers for IOL Power Calculations

The purpose of this study is to evaluate and compare the potential refractive outcomes using the Argos 1.5 biometer in the surgical planning for cataract extraction to that obtained from IOLMaster 700. Both devices are used as standard of care in surgical planning optimization for patients undergoing cataract surgery.

Study Overview

• Status: Recruiting
• Conditions: Cataract

Detailed Description

Cataract surgery is one of the most performed surgical procedures globally. The goal of the cataract surgeon is to implant an intraocular lens (IOL) with an appropriate IOL power to compensate for the refractive error and leave the patient emmetropic. The accurate measurement of ocular parameters is therefore critical for the effective calculation of IOL power, which directly impacts postoperative visual outcomes. However, accurate IOL power determination is influenced by several factors, including the measurement techniques employed and the specific biometers used in the process.

Optical biometry has become the gold standard for ocular measurements since the introduction of the IOLMaster (Carl Zeiss Meditec AG, Jena, Germany) in 2001. The IOLMaster 700 utilizes SWEPT Source OCT (SS-OCT) with a wavelength of about 1055 nm to generate a 2D OCT cornea-to-retina cross-section scan of the eye. This allows for the computation of all axial biometry measurements, including axial lengths (AL), central corneal thickness (CCT), anterior chamber depths (ACD), and lens thickness (LT).

A relatively newer biometer, Argos 1.5 is also non-invasive and based on SS-OCT technology for IOL power determination with a similar wavelength of 1060 nm ±10nm. However, the IOLMaster 700 uses a traditional axial length computation approach that relies on a single refractive index whiles Argos 1.5 uses a segmented axial length approach based on multiple refractive indices attributed to each ocular component often referred as True AL.

This study aims to evaluate and compare the potential refractive outcomes and biometric measurements of patients undergoing cataract surgery when using Argos 1.5 versus the IOLMaster 700 with the available formulas on each device. By analyzing these biometric measurements, we aim to uncover insights that could enhance our understanding of how different measurement techniques influence postoperative visual outcomes, ultimately contributing to improved patient care.

• Study Type: Observational
• Enrollment (Estimated): 50

Contacts and Locations

• Study Contact: Name: Lexi L Guild; Phone Number: 8012635705; Email: lguild@theeyeinstitute.com
• Study Contact Backup: Name: Allison Hales; Phone Number: 8012635735; Email: ahales@theeyeinstitute.com

Study Locations

• United States
  • Utah
    • Salt Lake City, Utah, United States, 84107
      • Recruiting
      • The Eye Institute of Utah
      • Contact: Allison Hales; Phone Number: 8012635735; Email: ahales@theeyeinstitute.com
      • Contact: Lexi Guild; Phone Number: 801-263-5705; Email: lguild@theeyeinstitute.com
      • Principal Investigator: Zachary J. Zavodni, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Subjects at least 21 years of age, meeting inclusion and exclusion criteria.

Description

Inclusion Criteria:

• 21 years or older (Adult age)
• Assessed to have Cataract Grade 1 and above per LOCS III or Wisconsin Grading scale in at least one eye.
• Able to comprehend and sign the informed consent form.
• Potential postoperative best corrected distance visual acuity (BCDVA) of 0.3 logMAR or better and targeted post-op refraction to be emmetropia, based on the investigator expert medical opinion.

Exclusion Criteria:

• No active ocular infection or inflammation
• Unable to fixate due to nystagmus or other eye movement abnormality (e.g., significant strabismus)
• Contraindicated for pupil dilation (e.g., narrow angles, allergies) per medical judgement of the investigator.
• Any ocular disease and/or condition that, in the investigator's clinical judgment, may put the subject at significant risk, may compromise study result or may interfere significantly with the subject's participation in the study.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Observational; No interventions will be administered.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Differences in predicted refraction	Predicted refraction is defined as the refractive power predicted by the IOL calculation formula. The predicted refraction for planned IOL power when using Argos 1.5 will be compared to IOL Master 700 for available formulae common to both devices (e.g. SRK/T, Barrett Universal II, Holladay I, Holladay II etc.) using forest plots. Data for Barrett TAL [Argos only] will be analysed using descriptive statistics	1 month

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Differences in the predicted IOL power for emmetropia	The differences in IOL predicted power will be compared using descriptive statistics and forest plots. For the second endpoint, we will be comparing the biometry measurements (ACD, CCT, WTW, LT, AL, K readings) from both devices for the same subject eye. The agreement will be quantified using Bland-Altman analysis for each measure for the total subject population.	1 month

Collaborators and Investigators

• Sponsor: The Eye institute of Utah
• Collaborators: Alcon Research
• Investigators: Principal Investigator: Zachary J Zavodni, MD, The Eye Institute of Utah

Study record dates

Study Major Dates

• Study Start (Actual): January 9, 2025
• Primary Completion (Estimated): February 7, 2025
• Study Completion (Estimated): February 22, 2025

Study Registration Dates

• First Submitted: January 24, 2025
• First Submitted That Met QC Criteria: January 29, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: January 29, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: Biometry; IOL Calculations; ARGOS; IOLM700; SS OCT Biometry
• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Cataract
• Other Study ID Numbers: 12809-ZJZavodni

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No