Subjective and Objective Refraction in Pseudophakic Patients

Not Applicable

Completed

• Conditions: Pseudophakia
• Interventions: Device: Subjective refraction; Device: Autorefraction; Device: Wavefront aberrometry

• Registration Number: NCT04319497
• Lead Sponsor: Vienna Institute for Research in Ocular Surgery

Brief Summary

Targeting of post-cataract refraction depends mainly on the prediction of the post-operative lens position, but also on the post-operative refraction itself. Hence, aim of this study is to evaluate the agreement and variability of subjective refraction performed by two independent examiners, autorefraction, and wavefront aberrometry in pseudophakic patients after uneventful cataract surgery.

Detailed Description

One of the main goals of modern cataract surgery, beside removing the cataractous lens, is to achieve the patient's desired post-operative refraction. Targeting this post-operative refraction depends mainly on the prediction of the post-operative lens position and the post-operative refraction itself. Reason for the contributing effect of post-operative refraction in the error-propagation analyses is that refraction in phakic patients was shown to have only moderate reproducibility.

In the past, different studies evaluated refraction methods. However, there is no study that included reproducibility of subjective refraction in pseudophakic patients and compares it with objective refraction methods (autorefraction, wavefront aberrometry).

100 eyes of 100 patients, which underwent uneventful cataract surgery, will be included in the study. Refraction of one eye of each patient will be tested using subjective refraction by two different examiners, autorefraction, and wavefront aberrometry at two separate occasions.

Study Timeline

• Study Start: 2013-03-20
• Primary Completion: 2014-08-20
• Study Completion: 2014-08-20
• Status Verified: 2020-03
• Study First Submitted: 2020-03-19
• Study First Submitted QC: 2020-03-20
• Last Update Submitted: 2020-03-20
• Study First Posted: 2020-03-24
• Last Update Posted: 2020-03-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• Minimum age: 21 years
• Cataract surgery (at least 8 weeks post-surgery)
• written informed consent

Exclusion Criteria

• Complications during or after cataract surgery
• Ophthalmic diseases, that might interfere with measurements (macular degeneration, glaucoma, diabetic retinopathia)
• Ophthalmic surgery other than cataract surgery
• Clinically significant posterior capsule opacification

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Refraction reproducibility and agreement	Autorefraction	Subjective and objective refraction will be performed in all patients
Refraction reproducibility and agreement	Wavefront aberrometry	Subjective and objective refraction will be performed in all patients
Refraction reproducibility and agreement	Subjective refraction	Subjective and objective refraction will be performed in all patients

Primary Outcome Measures

Name	Time	Method
Evaluation of the agreement between the subjective refraction measurements (in dioptres) of two examiners	12 months	To show the number of measurements within the limits of agreement, Bland-Altman plots will be created for subjective refraction measurements in dioptres between examiner 1 and examiner 2.

Secondary Outcome Measures

Name	Time	Method
Evaluation of reproducibility between the subjective refraction measurements between two study visits	12 months	To compare reproducibility of subjective refraction measurements between study visit 1 and study visit 2 Wilcoxon-signed rank test will be applied.
Evaluation of the reproducibility between measurements done with subjective refraction, autorefraction, and wavefront aberrometry in dioptres	12 months	To compare reproducibility between the 3 measurement methods in dioptres, Friedman's multiple comparison will be applied.
Evaluation of the agreement between the measurements performed by subjective refraction, autorefraction, and wavefront aberrometry (in dioptres)	12 months	To show the number of measurements within the limits of agreement, Bland-Altman plots will be created for subjective refraction measurements in dioptres between the 3 measurement methods.

Trial Locations

Locations (1)

Vienna Institute for Research in Ocular Surgery (VIROS); 🇦🇹 Vienna, Austria