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 measure
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 (if study stopped)
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
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
Basic results (scientific)
Publication list