Subjective and Objective Refraction in Pseudophakic Patients

Pseudophakia Clinical Trial

Official title:

Agreement and Variability of Subjective Refraction, Autorefraction, and Wavefront Aberrometry in Pseudophakic Patients

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04319497
• Other study ID #: Refraction
• Status: Completed
• Phase: N/A
• Start date: March 20, 2013
• Est. completion date: August 20, 2014

Study information

• Verified date: March 2020
• Source: Vienna Institute for Research in Ocular Surgery
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 100
• Est. completion date: August 20, 2014
• Est. primary completion date: August 20, 2014
• Accepts healthy volunteers: No
• Gender: All
• Age group: 21 Years to 105 Years

Eligibility

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

Related Conditions & MeSH terms

• Pseudophakia

Intervention

Device:
• Subjective refraction
Subjective refraction measurements will be performed by two testers for all the patients included
• Autorefraction
Five autorefraction measurements will be performed for all the patients included
• Wavefront aberrometry
Five wavefront measurements will be performed for all the patients included

Locations

Country	Name	City	State
Austria	Vienna Institute for Research in Ocular Surgery (VIROS)	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Vienna Institute for Research in Ocular Surgery

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Evaluation of the agreement between the subjective refraction measurements (in dioptres) of two examiners	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.	12 months
Secondary	Evaluation of reproducibility between the subjective refraction measurements between two study visits	To compare reproducibility of subjective refraction measurements between study visit 1 and study visit 2 Wilcoxon-signed rank test will be applied.	12 months
Secondary	Evaluation of the agreement between the measurements performed by subjective refraction, autorefraction, and wavefront aberrometry (in dioptres)	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.	12 months
Secondary	Evaluation of the reproducibility between measurements done with subjective refraction, autorefraction, and wavefront aberrometry in dioptres	To compare reproducibility between the 3 measurement methods in dioptres, Friedman's multiple comparison will be applied.	12 months