Clinical Trials Logo

Clinical Trial Summary

The vast majority of blindness is avoidable. The World Health Organization (WHO) estimates that 80% of cases of visual impairment could be prevented or reversed with early diagnosis and treatment. The leading causes of visual impairment are cataract and refractive error, followed by glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR). Loss of vision from these conditions is not inevitable; however, identifying at-risk cases and linking cases with appropriate care remain significant challenges. To address the global burden of avoidable blindness, eye care systems must determine optimal strategies for identifying people with or at risk for visual impairment beyond opportunistic screening. Outreach programs can prevent blindness both by screening for asymptomatic disease like age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma and case detection of symptomatic disease like cataract and refractive error. Eye care systems have developed numerous community-based approaches to these identification methods, including screening using telemedicine and case detection via cataract camps or community health worker models, but no studies have been conducted on the comparative effectiveness or cost effectiveness of these various approaches. Technology promises to greatly improve access to sophisticated eye care. AMD, DR, and glaucoma can result in irreversible vision loss, and early diagnosis and effective treatment can prevent progression.Thus, community screening programs may prevent progression and improve the vision of a population.However, mass screening for eye disease is currently not recommended. Although self-evident that early detection can prevent blindness for an individual, no randomized controlled trial has been able to demonstrate that screening improves visual acuity at the community level. However, recent technological advances promise to dramatically change the equation by allowing non-medical personnel to use mobile,easy-to-use retinal imaging devices to diagnose screenable eye diseases such as AMD, DR, and glaucoma. Mobile technology could also transform the way clinics communicate with their patients, improving linkage to and retention in care. Optical coherence tomography (OCT) is an ideal test for community-based screening. OCT can be performed through an undilated pupil and is less subject to optical aberrations due to cataract than is fundus photography. OCT machines have pre-installed algorithms to screen for glaucoma, and major anatomical abnormalities can easily be detected even by novice technicians. The infrared image allows detection of referable diabetic retinopathy, and newer OCT angiography machines offer even more discrimination of early diabetic retinopathy. OCT machines are ever more portable, and could be feasibly used in community-based screening programs. The investigators propose a large cluster-randomized trial in Nepal to compare two community-based blindness prevention programs: (1) a state-of-the-art screening program employing OCT and intraocular pressure testing to screen for glaucoma, DR, and AMD followed by enhanced linkage-to-care to the local eye hospital, and (2) a screening program involving only visual acuity assessment. An initial door-to-door census will assess baseline visual acuity in both study arms. The investigators will compare visual acuity between the two arms through a second door-to-door census 4 years later (primary outcome). The investigators maximize their chances of finding an effect by conducting the study in Nepal, where the burden of undiagnosed eye diseases is high. If successful in Nepal, future studies could assess the generalizability of such a program to other settings, such as rural communities in the industrialized world.


Clinical Trial Description

The research will consist of a large cluster-randomized trial in Nepal in which all communities receive visual acuity screening during a baseline census, and then half subsequently receive screening with OCT and intraocular pressure testing with an iCare tonometer. Participants with abnormal results will be referred to the local eye hospital for examination and treatment. Repeat visual acuity assessment will be performed 4 years later. Those with incident visual impairment at the time of the final census, defined as visual acuity worse than Snellen 20/60 (Metric Snellen worse than 6/18; logMAR worse than 0.48), will receive a comprehensive eye exam to determine the cause of visual impairment. Specific Aim 1 - Visual Acuity: To determine whether an intensive screening program results in better visual acuity at 4 years than screening with visual acuity testing alone. The investigators hypothesize that individuals from clusters randomized to the intensive screening program will have better visual acuity compared to those receiving visual acuity testing alone. Specific Aim 2 - Eye Disease: To determine whether an intensive screening program reduces the incidence of visual impairment due to AMD, DR, or glaucoma. The investigators hypothesize that incident visual impairment due to AMD, DR, or glaucoma will be less common in clusters randomized to the intensive screening program. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT03752840
Study type Interventional
Source University of California, San Francisco
Contact Krisianne M Aromin, BS
Phone 4154761442
Email krisianne.aromin@ucsf.edu
Status Recruiting
Phase N/A
Start date April 21, 2019
Completion date December 31, 2024

See also
  Status Clinical Trial Phase
Recruiting NCT06000865 - Glaucoma Rehabilitation With Action viDeo Games and Exercise - GRADE N/A
Recruiting NCT06278597 - Automatic Evaluation of the Anterior Chamber Angle Width by a New Non-contact Optical Device N/A
Active, not recruiting NCT04271709 - Manhattan Vision Screening and Follow-Up Study (NYC-SIGHT) N/A
Recruiting NCT03274024 - The Asia Primary Tube Versus Trab (TVT) Study N/A
Completed NCT04552964 - Assessment of the Impact of an add-on and Its Smartphone Application on the Daily Management of Glaucoma N/A
Recruiting NCT01957267 - Functional and Structural Imaging for Glaucoma
Active, not recruiting NCT04624698 - iStent Inject New Enrollment Post-Approval Study N/A
Completed NCT04020705 - The Efficacy of Citicoline in Eyedrops (OMK1) in Reducing the Progression of Glaucoma N/A
Completed NCT03150160 - Additive Effect of Twice-daily Brinzolamide 1%/Brimonidine 0.2%Combination as an Adjunctive Therapy to Travoprost in Patients With Normal Tension Glaucoma Phase 4
Not yet recruiting NCT05581498 - Glaucoma Exercise as Medicine Study (GEMS). N/A
Recruiting NCT02921568 - Side-by-Side Comparison of P200TE and Spectral OCT/SLO on Diseased Eyes N/A
Active, not recruiting NCT02901730 - Clinical Study of LPI With Different Laser Wavelengths N/A
Completed NCT02955849 - A Trial of China Laser and Surgery Study Glaucoma in Rural China Early Phase 1
Recruiting NCT02471105 - Investigation of IOP and Tolerability of Bimatoprost 0.01% and Tafluprost Unit Dose Preservative Free 15 Microgram/ml Phase 4
Recruiting NCT02554214 - Pilot Clinical Trial on a New Adjustable Glaucoma Drainage Device N/A
Active, not recruiting NCT02390284 - Stop Retinal Ganglion Cell Dysfunction Study Phase 3
Completed NCT02246764 - Study of Netarsudil (AR-13324) Ophthalmic Solution in Patients With Glaucoma or Ocular Hypertension Phase 3
Completed NCT02390245 - Philadelphia Telemedicine Glaucoma Detection and Follow-Up Study N/A
Completed NCT02653963 - Triamcinolone for Ahmed Glaucoma Valve N/A
Completed NCT02520674 - Glaucoma Screening With Smartphone Ophthalmology N/A