Comparison Between Two Ss-OCT Biometry

Study Overview
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Brief Summary
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Since recently a second swept-source optical coherence tomography (ss-OCT) optical biometry device was launched (Anterion, Heidelberg Engineering). Aim of this study is a retrospective data collection of patients who were measured with both ss-OCT optical biometry devices and to assess the limits of agreement of the two devices. Retrospective comparison of two ss-OCT biometry devices concerning comparability of measurements of axial eye length, anterior chamber depth, lens thickness and keratometry.

Detailed Description
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This a retrospective study including data acquired from patients that attended pre-surgical examination as it is the standard in the investigator's hospital. The IOL Master 700 (Carl Zeiss Meditec AG, Jena) and the Heidelberg Anterion (Heidelberg Engineering, Germany) are biometry devices that use swept-source optical coherence tomography technology in combination with a multidot-keratometer, that obtain two-dimensional images of ocular structures. The difference between the two devices resides in the wavelength of the infrared laser: 1200-1400nm for the Anterion and 1050nm for the IOL Master 700. The SS-OCT devices provide a scan depth of 44mm and a resolution in tissue of 22 μm for the IOL Master 700 and of 14x16.5 mm and 30 μm for the Heidelberg Anterion.

Official Title
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Comparison of Two Swept-Source Optical Coherence Tomography-based Biometry Devices

Conditions
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Cataract Senile

Intervention / Treatment
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* Other: Biometric measurement agreement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age-related cataract Exclusion Criteria: nystagmus physical inabilities that could interfere with fixation dens cataract macular or corneal pathologies that could compromise fixation during the measurements.

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Biometric measurement agreement|Patients scheduled for cataract surgery were measured with both ss-OCT devices. The following biometry parameters were compared: anterior keratometry, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and axial length (AL).|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Limits of agreement between two optical biometers using the same SS-OCT technology for the following parameters AL, ACD, LT (evaluated in mm) | For descriptive analysis, Kolmogorov Smirnov test will be used to evaluate normal distribution. The student T test for paired samples and Wilcoxon for nonparametric data was used to compare parameters as: AL, ACD, LT. The limits of agreement (1.96xSD) between two optical biometers were calculated and represented graphically using Bland-Altman graphs | 6 months | 
| Limits of agreement between two optical biometers using the same SS-OCT technology for the following parameters CCT (evaluated in micrometer) | For descriptive analysis, Kolmogorov Smirnov test will be used to evaluate normal distribution. The student T test for paired samples and Wilcoxon for nonparametric data was used to compare the CCT data The limits of agreement (1.96xSD) between two optical biometers were calculated and represented graphically using Bland-Altman graphs | 6 months | 
| Limits of agreement between two optical biometers using the same SS-OCT technology for the following parameter: keratometry (evaluated in diopter) | For descriptive analysis, Kolmogorov Smirnov test will be used to evaluate normal distribution. The student T test for paired samples and Wilcoxon for nonparametric data was used to compare keratometry data The limits of agreement (1.96xSD) between two optical biometers were calculated and represented graphically using Bland-Altman graphs | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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biometry, ss-OCT, cataract