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CompletedNCT03592017Updated Aug 21, 2024

Performance of Long-wavelength Autofluorescence Imaging

An interventional study of Long-wavelength autofluorescence imaging in Retinal Disease, Retinal Degeneration and Retinal Dystrophies, sponsored by Oxford University Hospitals NHS Trust. Completed at 1 site in United Kingdom. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-08-21.

Sponsored by Oxford University Hospitals NHS Trust · Not applicable, Interventional, and Diagnostic

Phase
Not applicable
Study type
Interventional
Enrollment
262
Allocation
Non-randomized
Ages
18 Years and older
Sex
All
01

Study summary

Fundus autofluorescence imaging has become an important diagnostic tool in ophthalmology, guiding diagnosis and assessment of progression of retinal diseases. This study investigates the performance of optimized long-wavelength autofluorescence imaging. To achieve this goal, the investigators will determine an optimal long wavelength excitation light and investigate the autofluorescence signal intensity in normals and patients with different retinal diseases. The diagnostic performance of the long-wavelength autofluorescence will be evaluated by assessing sensitivity and specificity for diagnosing a variety of degenerative retinal diseases and by comparing it to conventional autofluorescence.

Read the detailed description

Fundus autofluorescence (AF) imaging of the retina with confocal scanning laser ophthalmoscopy has been established as a non-invasive imaging modality for the diagnosis of retinal and macular diseases. Long-wavelength near-infrared autofluorescence (excitation: 787 nm, LW-AF) is a new, innovative alternative to the classic autofluorescence imaging using 488 nm blue excitation light. Excitation of the fluorophores at the ocular fundus using a longer wavelength has several advantages. However, with the current imaging technique the autofluorescence signal and thus image quality is considerably lower compared to conventional short-wavelength autofluorescence (SW-AF). This may be the main reason for the currently limited application and scarce scientific publications on this technique.

Therefore, the objective of this study is to assess the performance of an optimized setup of long-wavelength autofluorescence imaging in clinical routine applications. For this purpose, additional laser sources will be integrated into a scanning laser ophthalmoscope and the performance with regards to image quality will be investigated systematically using different excitation wavelengths and filter combinations in healthy controls.

In a next step, the signal intensity will be quantified using an integrated fluorescent reference. First, factors affecting measurements will be identified, followed by generation of a normative database. Subjects with various retinal diseases will then be investigated and compared to the normative database.

Finally, the diagnostic performance of long-wavelength autofluorescence imaging to detect retinal degenerative diseases will be investigated and compared to conventional imaging techniques.

02

Conditions studied

  • Retinal Disease
  • Retinal Degeneration
  • Retinal Dystrophies
03

In context

Retinal Diseases

815 studies on the registry are indexed under Retinal Diseases; 105 are open to participants now.

This study's enrollment of 262 is above the median of 60 across 500 interventional studies indexed under Retinal Diseases.

Browse Retinal Diseases studies →

Lead sponsor

Oxford University Hospitals NHS Trust is the lead sponsor of 92 studies on the registry; 7 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Age 18 years or above
  • Defined retinal disease (patients) or no known retinal disease (healthy participants)
  • Participants willing to read and understand the study information and provide informed consent
  • Participants agree to have some examinations and photographs taken from their eyes

Exclusion criteria

Exclusion Criteria:

  • Significant opacities of the ocular media
  • difficulties positioning still in front of the camera
  • any ocular/ general disease known to affect recordings and/or analysis of retinal images
  • Pupil diameter \<5mm
05

Study design

Phase
Not applicable
Primary purpose
Diagnostic
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
262 participants (actual)

Study arms

  • Experimental
    Patients with various retinal diseases

    Patients with various retinal diseases will be examined using long-wavelength autofluorescence imaging to assess the performance compared to conventional imaging methods and to quantify the signal compared to a normative database

    Device: Long-wavelength autofluorescence imaging

  • Experimental
    Healthy participants

    Healthy participants will be examined using long-wavelength autofluorescence imaging to optimize the signal with additional laser sources and device settings and to compile a normative database for the quantification of the signal.

    Device: Long-wavelength autofluorescence imaging

Interventions

  • DeviceLong-wavelength autofluorescence imaging

    Long-wavelength autofluorescence imaging will be performed with a prototype confocal scanning laser (cSLO) ophthalmoscope which will be equipped with additional laser sources and a reference for quantification of the signal. The experimental long-wavelength laser sources will be integrated into a custom-modified Spectralis HRA cSLO from Heidelberg Engineering. The additional laser sources will operate with long wavelength which are less energetic compared to the conventional short-wavelength lasers used currently for routine autofluorescence imaging. All safety standards have been considered and the light exposure for all imaging modes is well below the exposure limits for Class 1 and Class1M laser products as defined in the standard IEC 60825-1, edition 3.0, 2014-5.

06

What researchers measure

Primary outcomes

  1. Performance of long-wavelength autofluorescence imaging

    The sensitivity and specificity to detect characteristics in retinal diseases will be investigated in patients with various retinal diseases and compared to conventional imaging methods

    Time frame: 1 day

Secondary outcomes

  1. Optimization of the signal of long-wavelength autofluorescence imaging using different laser and filter settings

    To optimize the signal of long-wavelength autofluorescence imaging, the fluorescence intensity of the different laser sources and filter settings will be assessed.

    Time frame: 1 day

  2. Quantification of the optimized signal of long-wavelength autofluorescence imaging in healthy controls and participants with various retinal diseases

    To quantify the optimized signal of long-wavelength autofluorescence imaging the absolute fluorescence intensity compared to a fluorescent reference will be assessed in patients with various retinal diseases and compared to healthy controls

    Time frame: 1 day

07

Study locations

1 site
  • Oxford Eye Hospital
    Oxford, OX3 9DU, United Kingdom
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 21, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03592017
Lead sponsor
Oxford University Hospitals NHS Trust
Responsible party
Sponsor
First posted
Jul 19, 2018
Start date
Oct 1, 2018
Primary completion
Apr 9, 2024
Completion
Apr 9, 2024
Last update
Aug 21, 2024

Study contacts

Peter Charbel Issa, DPhil, MD
principal investigator · Oxford Eye Hospital, The West Wing John Radcliffe Hospital Oxford, OX3 9DU

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Aug 2024. You cannot join it, but the record below documents what was studied.

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