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COmparison of Clarus and Optos Ultrawide Field Imaging Systems for Geographic Atrophy

COmparison of Clarus and Optos Ultrawide Field Imaging Systems for Geographic Atrophy (COCO-GA) Protocol

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05961332
Acronym
COCO-GA
Enrollment
62
Registered
2023-07-27
Start date
2023-10-06
Completion date
2025-05-27
Last updated
2026-07-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Geographic Atrophy, Macular Degeneration, Age Related

Brief summary

The goal of this clinical trial is to compare measurements of geographic atrophy (GA) area between several types of imaging, in order to assess accuracy. The main question to answer is which imaging device provides measurements that are most similar to the standard of care device. Participants will be patients of a retina doctor at University Station Eye Clinic with geographic atrophy, and can expect to be in the study for 60-75 minutes.

Detailed description

This study is a single site pilot comparative imaging study in which enrolled participants will undergo dilated fundus exam as per standard of care. Study images will be obtained using Optos ultrawide field fundus autofluorescence (FAF) and both blue and green ultrawide field FAF with Zeiss Clarus. Autofluorescence (AF) imaging will also be performed on the Spectralis as it is currently the gold standard. The goal will be to obtain all images in 60-75 minutes over one visit. Images will be assessed, and area of geographic atrophy measured independently by two experienced readers.

Interventions

Spectralis is a scanning laser ophthalmoscope which uses a blue light excitation wavelength of 488nm and a 500nm barrier filter to produce FAF images. Spectralis images 20-55 degrees of the retina.

Optos is an ultrawide field imaging platform which images up to 200 degrees of the retina. It uses both a green-light excitation wavelength of 532nm and a red-light excitation wavelength of 633nm with an emission filter of greater than 540nm to produce FAF images.

DEVICEZeiss Clarus 700 imaging

Zeiss Clarus 700 is an ultrawide field imaging system with similar retinal coverage to that of Optos. It uses Broad Line Fundus Imaging to produce blue FAF images at excitation wavelengths of 435-500nm and green FAF images at wavelengths of 500-585nm

Sponsors

University of Wisconsin, Madison
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
50 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 50 years or older and may be either male or female and may be of any race * Established diagnosis of GA due to AMD * GA characteristics: GA area of between 1.25 mm² and 23 mm², with seventy percent of eyes having GA area ranging from 2.5 mm² to 17.5 mm². GA may be unifocal or multifocal. GA may be subfoveal or extrafoveal, with twenty-five percent of eyes having subfoveal GA. The presence of concurrent peripapillary atrophy will not exclude subjects from participation * Willing to participate as evidenced by signing the written informed consent

Exclusion criteria

* Unable to tolerate opthalmic imaging * Presence of neovascular AMD on OCT as confirmed by an ophthalmologist * Presence of significant media opacity preventing adequate retinal imaging * Presence of concurrent retinal disease which may confound assessment

Design outcomes

Primary

MeasureTime frameDescription
Comparison of Geographic Atrophy Area Measurements With Heidelberg Spectralis to Zeiss Clarus 700 and Optos CaliforniaUp to 75 minutesGraders will independently measure area of GA from images of each device. The measurements (in mm²) will be compared between the devices.
Comparison of Geographic Atrophy Area Measurements With Heidelberg Spectralis to Zeiss Clarus 700 and Optos California (Full Range Reported)Up to 75 minutesGraders will independently measure area of GA from images of each device. The measurements (in mm²) will be compared between the devices.
Number of Eyes With Greater Than 10% Difference in Geographic Atrophy Area Than Heidelberg RegionFinderup to 75 mintues

Secondary

MeasureTime frameDescription
Prevalence of Atrophy Outside the Standard 30 Degrees in Clarus and Optos Ultrawide Field ImagesUp to 75 minutesThe presence of atrophy outside field 2 will be documented from the two ultrawide field imaging devices
Prevalence of Other Autofluorescence Abnormalities Outside the Standard 30 Degrees in Clarus and Optos Ultrawide Field ImagesUp to 75 minutesThe presence of abnormal autofluorescence outside field 2 will be documented from the two ultrawide field imaging devices

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORAmitha Domalpally, MD, PhD

University of Wisconsin, Madison

Baseline characteristics

Characteristic
Age, Customized
50 years or greater
62 Participants
Age, Customized
less than 50 years
0 Participants
Region of Enrollment
United States
62 participants
Sex: Female, Male
Female
43 Participants
Sex: Female, Male
Male
19 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 620 / 620 / 62
other
Total, other adverse events
0 / 620 / 620 / 62
serious
Total, serious adverse events
0 / 620 / 620 / 62

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 11, 2026