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Completed

NCT Number: NCT04319497

Subjective and Objective Refraction in Pseudophakic Patients

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.

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Key information

Conditions

Pseudophakia Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

21 year–105 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Vienna Institute for Research in Ocular Surgery (VIROS)

Vienna, 1140, Austria

About this study

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.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Subjective refraction

Device

Subjective refraction measurements will be performed by two testers for all the patients included

Autorefraction

Device

Five autorefraction measurements will be performed for all the patients included

Wavefront aberrometry

Device

Five wavefront measurements will be performed for all the patients included

Primary outcomes

  1. Evaluation of the agreement between the subjective refraction measurements (in dioptres) of two examiners

    Time frame: 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 outcomes

  1. Evaluation of reproducibility between the subjective refraction measurements between two study visits

    Time frame: 12 months

    To compare reproducibility of subjective refraction measurements between study visit 1 and study visit 2 Wilcoxon-signed rank test will be applied.

  2. Evaluation of the agreement between the measurements performed by subjective refraction, autorefraction, and wavefront aberrometry (in dioptres)

    Time frame: 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.

  3. Evaluation of the reproducibility between measurements done with subjective refraction, autorefraction, and wavefront aberrometry in dioptres

    Time frame: 12 months

    To compare reproducibility between the 3 measurement methods in dioptres, Friedman's multiple comparison will be applied.

Sponsors and collaborators

Lead sponsor

Vienna Institute for Research in Ocular Surgery

Other

Registry information

Official study title

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

Important dates

Study start
2013
Primary completion
2014
Study completion
2014
First posted
Mar 24, 2020
Registry last updated
Mar 24, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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