Low Vision Clinical Trial
— RGPIRIS_PAOfficial title:
Evaluation of Light Sensitivity and Visual Acuity Changes as Consequence of Rigid Gas Permeable (RGP) Scleral Contact Lenses With a Passive Artificial Iris
Verified date | November 2021 |
Source | University Ghent |
Contact | n/a |
Is FDA regulated | No |
Health authority | |
Study type | Interventional |
Data from 15 healthy subjects will be recorded in two testing sessions spread on two days, using three lens designs (A, B and C). Before the measuring days, each subject will undergo an extra fitting session of a large-diameter scleral contact lens on the dominant eye, assessed by an experienced practitioner. The fitting data will be used to custom-make the three lens designs for each subject, thus ensuring their comfort and safety during the days of the experiments. During the experiment days baseline measurements will be obtained before and after pupil dilation and contact lens wear. During the first testing session data from the lens design A (reference lens without artificial iris) will be recorded. During the second testing session data from the lens designs B and C (lenses with artificial iris with different transmittances) will be recorded. In each testing session, contrast sensitivity and visual acuity will be evaluated and non-invasive imaging measurements will be undertaken (optical coherence tomography and slit lamp). A specific questionnaire will be given to the subject to assess comfort, light sensitivity, the horizontal visual angle and overall experience of the scleral lens and in combination with a pair of sunglasses category 3-4.
Status | Terminated |
Enrollment | 10 |
Est. completion date | June 22, 2021 |
Est. primary completion date | June 22, 2021 |
Accepts healthy volunteers | Accepts Healthy Volunteers |
Gender | All |
Age group | 18 Years to 45 Years |
Eligibility | Inclusion Criteria: - Age between 18 and 45 years old Exclusion Criteria: - Iris disorders (i.e. ocular albinism, coloboma, aniridia). - Known disease-related ocular surface problem (i.e. microbial keratitis). - Known ocular pathologies (except refractive disorders). - Coexistent ocular diseases impeding contact lens correction (i.e. glaucoma, previous ocular surgery). - Corneal scarring. - Low corneal endothelial cell count (< 1500 cells per mm2), with potential of corneal hypoxia-induced corneal edema induced by contact lens wear. - Wearing of contact lenses in the last 24 hours (prior to the interventions). |
Country | Name | City | State |
---|---|---|---|
Belgium | University Hospital Ghent (UZGent) | Ghent |
Lead Sponsor | Collaborator |
---|---|
University Ghent |
Belgium,
Compañ V, Oliveira C, Aguilella-Arzo M, Mollá S, Peixoto-de-Matos SC, González-Méijome JM. Oxygen diffusion and edema with modern scleral rigid gas permeable contact lenses. Invest Ophthalmol Vis Sci. 2014 Sep 4;55(10):6421-9. doi: 10.1167/iovs.14-14038. — View Citation
Eyeson-Annan ML, Hirst LW, Battistutta D, Green A. Comparative pupil dilation using phenylephrine alone or in combination with tropicamide. Ophthalmology. 1998 Apr;105(4):726-32. — View Citation
García-Lázaro S, Ferrer-Blasco T, Radhakrishnan H, Cerviño A, Charman WN, Montés-Micó R. Visual function through 4 contact lens-based pinhole systems for presbyopia. J Cataract Refract Surg. 2012 May;38(5):858-65. doi: 10.1016/j.jcrs.2011.11.042. Epub 2012 Mar 16. — View Citation
Holden BA, Mertz GW. Critical oxygen levels to avoid corneal edema for daily and extended wear contact lenses. Invest Ophthalmol Vis Sci. 1984 Oct;25(10):1161-7. — View Citation
Pepose JS. Small-aperture contact lenses for presbyopia. J Cataract Refract Surg. 2012 Nov;38(11):2060-1; author reply 2062-4. doi: 10.1016/j.jcrs.2012.08.041. — View Citation
Xu R, Gil D, Dibas M, Hare W, Bradley A. The Effect of Light Level and Small Pupils on Presbyopic Reading Performance. Invest Ophthalmol Vis Sci. 2016 Oct 1;57(13):5656-5664. doi: 10.1167/iovs.16-20008. — View Citation
Type | Measure | Description | Time frame | Safety issue |
---|---|---|---|---|
Primary | Visual acuity assessment and comparison between Designs A, B and C by means of logMAR or equivalent value | Compare visual acuity values obtained with different designs | 5 months from fitting session | |
Primary | Contrast sensitivity assessment and comparison between Designs A, B and C by means of threshold percentage or equivalent value | Compare contrast sensitivity values obtained with different designs | 5 months from fitting session | |
Secondary | Device safety by comparing eventual adverse events with those found in scleral contact lenses | Comparing adverse event of similar devices | 5 months from fitting session | |
Secondary | Correct fitting | Taking and analyzing ocular coherence tomography (OCT) images and slit lamp observations to estimate the clearance | 5 months from fitting session | |
Secondary | Contact lens wear comfort, as assessed by subject data from questionnaires Rasch analyzed using a 4-Andrich ration scale model | The subjective assessment will be carried out by means of questions on 3 content areas: lens comfort (3 questions), visual quality (4 questions) and general satisfaction with the lenses (3 questions). | 5 months from fitting session | |
Secondary | Visual acuity assessment and comparison between Designs B (low contrast) and C (high contrast) by means of logMAR or equivalent value | Comparing visual acuity between Designs B and C | 5 months from fitting session | |
Secondary | Contrast sensitivity assessment and comparison between Designs B (low contrast) and C (high contrast) by means of threshold percentage or equivalent value | Comparing contrast sensitivity between Designs B and C | 5 months from fitting session | |
Secondary | Horizontal visual angle | Angle at which the volunteer can see his fingers move when extending the arm (same side as dominant eye), 0°=arm extended to the side; 90°=arm straight ahead | 5 months from fitting session |
Status | Clinical Trial | Phase | |
---|---|---|---|
Recruiting |
NCT04929756 -
Eye Movement Rehabilitation in Low Vision Patients
|
||
Completed |
NCT04974307 -
Optic-to-Audio Device in a Pediatric Cohort With CLN3-related Conditions or Low Vision
|
N/A | |
Completed |
NCT02310880 -
Efficacy of Enhancing Low Vision Mobility Thru Visual Training in Virtual World
|
N/A | |
Recruiting |
NCT06107881 -
Beacon Sensors and Telerehabilitation to Assess and Improve Use of Devices (BeST-AID) for Low Vision
|
N/A | |
Completed |
NCT00545220 -
Problem Solving Training and Low Vision Rehabilitation
|
N/A | |
Recruiting |
NCT04066075 -
Beacon Sensors and Telerehabilitation for Low Vision
|
N/A | |
Recruiting |
NCT04281732 -
Visual Performance Measures in a Virtual Reality Environment for Assessing Clinical Trial Outcomes in Those With Severely Reduced Vision
|
||
Completed |
NCT01217502 -
Self-management for Dual Sensory Impaired
|
N/A | |
Completed |
NCT00946062 -
Evaluation of a Standardised Orientation and Mobility Training in Older Adults With Low Vision
|
N/A | |
Terminated |
NCT04276610 -
Words on the Brain: Can Reading Rehabilitation for Age-Related Vision Impairment Improve Cognitive Functioning?
|
N/A | |
Recruiting |
NCT05829135 -
Improving Glare and Visual Comfort for Patients With Visual Impairment
|
N/A | |
Completed |
NCT04242836 -
Development and Validation of a Digital Optotype for Near Vision in Greek Language.
|
||
Terminated |
NCT03353727 -
Orthoptic Rehabilitation for Low Vision People With Innovative Mechanisms (Eye Tracker and Tactile Device)
|
N/A | |
Completed |
NCT04926974 -
Community Access Through Remote Eyesight (CARE) Study
|
N/A | |
Completed |
NCT00348621 -
A Study of Interventions to Reduce Disability From Visual Loss in Nursing Home Residents
|
Phase 4 | |
Not yet recruiting |
NCT03104608 -
Automatic Self Transcending Meditation (ASTM) for Patients With Severe Age Related Macular Degeneration (AMD)
|
N/A | |
Completed |
NCT05491746 -
Diabetic Retinopathy Tethered Augmented Reality With Eye4 Study
|
N/A | |
Completed |
NCT03728660 -
Design and Clinical Evaluation of a Smartphone-based Low Vision Enhancement System
|
N/A | |
Completed |
NCT05209581 -
Assessment of Visual Acuity in Refugee Population
|
||
Recruiting |
NCT01879501 -
Living Successfully With Chronic Eye Diseases
|
N/A |