Fundus autofluorescence (FAF) is a non-invasive, high definition scan of the deeper retinal layers at the back of the eye. FAF highlights areas of metabolic stress in detail that is above and beyond that of conventional retinal cameras.

Innovative Eye Care uses the top of the range Heidelberg Blue laser autofluorescence to take high definition images of the retina. This offers diagnostic insights into a number of retinal conditions, including macular degeneration, plaquenil toxicity, and hereditary diseases.

What is FAF?

The retina contains a metabolic indicator called lipofuscin, commonly referred to as the “wear and tear” pigment.1, 2 When light of 488nm is shone onto the retina, lipofuscin fluoresces and the amount of fluorescence corresponds with the amount of lipofuscin present.1 A number of hereditary and complex retinal diseases (including macular degeneration ) have characteristic increases or decreases in the amount of lipofuscin present in the retina.2, 3, 4 FAF provides detailed analysis of these conditions that allow the optometrists at Innovative Eye Care to accurately monitor your retinal health.

FAF image of a healthy eye

Age Related Macular Degeneration (AMD)

In the western world, wet AMD is a leading cause of legal blindness in those over 50 years of age.5 Research indicates that approximately 55-70% of patients with AMD are undiagnosed, indicating an inadequacy in current conventional screening methods.6

Accumulation of lipofuscin in the RPE (layer under the retina) is strongly associated with the progression of AMD. Areas of high autofluorescence (i.e. more lipofuscin) correlate to dysfunctional photoreceptors and vision loss.1 FAF images allow for monitoring of subtle retinal and RPE changes, particularly in early stages.

Hereditary Retinal Diseases

Hereditary retinal conditions, such as retinitis pigmentosa (RP), cone dystrophy, Best’s disease, Stargardt’s disease and vitelliform macular dystrophy are visually debillitating conditions that manifest with changes in metabolic activity of the RPE (layer under the retina). This can be detected effectively using FAF imaging to monitor for early changes in at risk individuals.

Plaquenil Retinopathy

Plaquenil is used commonly for the treatment of systemic lupus erythmatosus (SLE), rheumatoid arthritis, and other inflammatory conditions. Retinal toxicity from plaquenil use has been recognised for many years, with the risk of toxicity being largely dependent on dosage and duration of treatment.7 Plaquenil toxicity cannot be treated and can potentially cause irreversible loss of central vision.7 Studies have shown that central vision can be preserved if damage is detected prior to changes in the RPE (layer under the retina).7

The American Academy of Ophthalmology recommend a baseline visual screening within the first year of commencing the drug.7 Typically, annual visual screenings should commence after there has been five years of exposure to the drug. This may be more frequent if other risk factors are present. Visual screenings for plaquenil toxicity include automated visual fields, OCT and FAF. 7

References

  1. Lois N, Forrester JV. Fundus Auto fluorescence. Philadelphia: Lippincott Williams & Wilkins; 2009.
  2. Amin, XU. Changzheng, Chen. (2018). “Clinical application of ultra-wide field fundus auto fluorescence imaging”. Chinese Journal of Ocular Fundus Diseases. 34(1): 89-92.
  3. Frampton, GK. Kalita, N. Payne, L. Colquitt, J. Loveman, E. (2016). “Accuracy of fundus auto fluorescence imaging for the diagnosis and monitoring of retinal conditions: a systematic review.” Health Technol Assess. 20(31).
  4. Theelen T, Berendschot TT, Boon CJ, Hoyng CB, Klevering BJ. (2008). “Analysis of visual pigment by fundus autofluorescence.” Exp Eye Res.86:296-304.
  5. Keel, S. et al. (2017). “Prevalence of Age-Related Macular Degeneration in Australia”. Jama Ophthalmol. 135(11):1242-1249.
  6. Practice management in the era of anti-VEGF therapy. Ophthalmology Time Europe; 2006(2)4:S1-8.
  7. Marmor, M. Kellner, U. Lai, T. Melles, R. Mieler, W. (2016). “Recommendations on screening for chloroquine and hydroxychloroquine retinopathy (2016 revision)”. American Academy of Ophthalmology. 123(6): 1386-1394.
  8. Lois N, Forrester JV. Fundus Auto fluorescence. Philadelphia: Lippincott Williams & Wilkins; 2009.
  9. Amin, XU. Changzheng, Chen. (2018). “Clinical application of ultra-wide field fundus auto fluorescence imaging”. Chinese Journal of Ocular Fundus Diseases. 34(1): 89-92.
  10. Frampton, GK. Kalita, N. Payne, L. Colquitt, J. Loveman, E. (2016). “Accuracy of fundus auto fluorescence imaging for the diagnosis and monitoring of retinal conditions: a systematic review.” Health Technol Assess. 20(31).
  11. Theelen T, Berendschot TT, Boon CJ, Hoyng CB, Klevering BJ. (2008). “Analysis of visual pigment by fundus autofluorescence.” Exp Eye Res.86:296-304.
  12. Keel, S. et al. (2017). “Prevalence of Age-Related Macular Degeneration in Australia”. Jama Ophthalmol. 135(11):1242-1249.
  13. Practice management in the era of anti-VEGF therapy. Ophthalmology Time Europe; 2006(2)4:S1-8.
  14. Marmor, M. Kellner, U. Lai, T. Melles, R. Mieler, W. (2016). “Recommendations on screening for chloroquine and hydroxychloroquine retinopathy (2016 revision)”. American Academy of Ophthalmology. 123(6): 1386-1394.