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Fluorescence Lifetime Macro Imager for Biomedical Applications
Published on: April 7, 2023
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Fluorescence lifetime imaging ophthalmoscopy: autofluorescence imaging and beyond
Lydia Sauer1, Alexandra S Vitale1, Natalie K Modersitzki1
1Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
Eye (London, England)
|December 3, 2020
Summary
Fluorescence lifetime imaging ophthalmoscopy (FLIO) is a noninvasive eye imaging technique. FLIO provides valuable insights into retinal diseases like AMD and Stargardt disease, detecting changes earlier than conventional methods.
Area of Science:
- Ophthalmology
- Medical Imaging
- Biophotonics
Background:
- Fluorescence lifetime imaging ophthalmoscopy (FLIO) is an emerging noninvasive imaging technique.
- It offers complementary information to conventional ophthalmic imaging modalities.
- The FLIO device utilizes a Heidelberg Engineering Spectralis system for autofluorescence lifetime measurements.
Purpose of the Study:
- To review the current knowledge, clinical benefits, and limitations of FLIO imaging.
- To highlight the application of FLIO in various ophthalmic and systemic diseases.
- To provide an outlook on the future potential of FLIO technology.
Main Methods:
- Autofluorescence lifetimes are excited at 473 nm.
- Measurements are recorded in short spectral channel (SSC, 498-560 nm) and long spectral channel (LSC, 560-720 nm).
- Mean autofluorescence lifetimes are typically analyzed within a 30° retinal field.
Main Results:
- FLIO demonstrates significant benefits in imaging diverse retinal diseases.
- Characteristic FLIO lifetime patterns are observed in age-related macular degeneration (AMD), macular telangiectasia type 2 (MacTel), and Stargardt disease.
- FLIO can detect early hydroxychloroquine toxicity and visualize retinal flecks in Stargardt disease before they are apparent with other methods.
Conclusions:
- FLIO is a valuable tool for the early detection and characterization of retinal diseases.
- The technique shows promise for monitoring disease progression and treatment response.
- Further research is warranted to fully explore the diagnostic and therapeutic potential of FLIO imaging.
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