Condition category
Not Applicable
Date applied
01/12/2006
Date assigned
01/12/2006
Last edited
14/12/2006
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Ms K W van Gaalen

ORCID ID

Contact details

University Medical Center
Groningen
Department of Ophtalmology
P.O. Box 30001
Groningen
9700 RB
Netherlands
+31 (0)50 3619692
k.van.gaalen@ohk.umcg.nl

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

1

Study information

Scientific title

Acronym

Defocus specific contrast sensitivity and spherical aberration

Study hypothesis

Higher order aberrations, like spherical aberration, decreases visual performance.

Ethics approval

Medisch Ethische Toetsingscommissie, University Medical Center Groningen, date of MEC approval: 14 Oct 2005 (reference number: METc2005.188).

Study design

Randomised parallel armed clinical trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type

Treatment

Patient information sheet

Condition

No condition, healthy person

Intervention

Best corrected visual acuity was determined with an Early Treatment Diabetic Retinopathy Study (ETDRS ) chart and the Spherical Aberration (SA) was measured with a wavefront analyzer (WASCA version 1.26.3, Asclepion Meditec, Jena, Germany).

The contrast sensitivity is measured with two computerised tests:
1. One with vertical sine-wave gratings (1.5-12 cpd) generated on a CRT (Cambridge Research Systems, Rochester, UK; Von Bekesy tracking method)
2. The Holladay sine-wave (1.5 -18 cpd) modulated circular lines (HACSS) (M&S Technologies, Skokie, Illinois, USA),

and with six contrast sensitivity chart tests:
1. Pelli Robson contrast sensitivity test
2. Low contrast ETDRS-like optotype chart 2.5%
3. Low contrast ETDRS-like optotype chart 10%
4. Edge contrast sensitivity test: GECKO
5. Edge contrast sensitivity test: GECKO-100
6. Vector Vision

Contrast sensitivity is measured in mesopic (3 cd/m^2) and photopic (160 cd/m^2) conditions, using only the dominant eye. Tests were performed at optimal refractive state of the eye and at a variety of defocus situations (-2D to 2D).

Intervention type

Other

Phase

Not Specified

Drug names

Primary outcome measures

Selection of the contrast sensitivity test which predicts the spherical aberration most reliably.

Secondary outcome measures

1. Spherical aberration as function of age
2. RMS as function of age
3. Contrast sensitivity as function of age
4. Influence of defocus on contrast sensitivity

Overall trial start date

01/07/2005

Overall trial end date

30/06/2006

Reason abandoned

Eligibility

Participant inclusion criteria

No ocular pathology

Participant type

Patient

Age group

Not Specified

Gender

Not Specified

Target number of participants

48

Participant exclusion criteria

1. Refractive correction larger than +/- 2 D
2. Cylindrical correction larger than 1.5 D
3. Cylindrical axis more then 20° from the horizontal or vertical axis

Recruitment start date

01/07/2005

Recruitment end date

30/06/2006

Locations

Countries of recruitment

Netherlands

Trial participating centre

University Medical Center
Groningen
9700 RB
Netherlands

Sponsor information

Organisation

University Medical Center Groningen (The Netherlands)

Sponsor details

Department of Ophtalmology
P.O. Box 30001
Groningen
9700 RB
Netherlands

Sponsor type

Hospital/treatment centre

Website

http://www.umcg.nl/azg/nl/english/azg/

Funders

Funder type

Government

Funder name

SenterNovem (The Netherlands)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes