June 2021
Volume 62, Issue 8
Open Access
ARVO Annual Meeting Abstract  |   June 2021
Feasibility of fast measurement of macular pigment optical density using a slit-scanning ophthalmoscope
Author Affiliations & Notes
  • Conor Leahy
    Carl Zeiss Meditec Inc, California, United States
  • Angelina Covita
    Carl Zeiss Meditec Inc, California, United States
  • Footnotes
    Commercial Relationships   Conor Leahy, Carl Zeiss Meditec, Inc. (E); Angelina Covita, Carl Zeiss Meditec, Inc. (E)
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science June 2021, Vol.62, 1871. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Conor Leahy, Angelina Covita; Feasibility of fast measurement of macular pigment optical density using a slit-scanning ophthalmoscope. Invest. Ophthalmol. Vis. Sci. 2021;62(8):1871.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : Objective, non-invasive measurement of the optical density (OD) of human macular pigment (MP) can be performed in vivo using fundus autofluorescence (FAF) imaging. Depending on the protocol used, the exam duration may be lengthened by the need for pupil dilation, repeat image acquisitions, and/or separate calibration for crystalline lens fluorescence. In this study, we investigate the feasibility of quantifying macular pigment optical density (MPOD) using a slit-scanning ophthalmoscope with a single-flash measurement protocol.

Methods : A slit-scanning ophthalmoscope (CLARUSTM 500, ZEISS, Dublin, CA) with prototype software was used to perform non-mydriatic measurements of MPOD, derived from pairs of FAF images obtained with blue (λpeak = 459nm, well-absorbed by MP) and green (λpeak = 520nm, much less absorbed) excitation sources. The illumination rapidly alternates between the sources during a single scan, completing in under 0.2 seconds. The image sensor records separately the partial images of stripes of illuminated retina. Retinal autofluorescence appears only within the illuminated stripe, but unwanted crystalline lens fluorescence appears nearly uniformly across the partial image (allowing it to be removed). A fluorescent phantom, incorporating a yellow-colored filter of known OD, was used to test the implementation. MPOD measurements were performed on 5 human subjects.

Results : The manufacturer specified OD for the test phantom is shown in Figure 1A. From the FAF images (Figure 1B-C), the 2-D spatial MPOD profile for the test phantom is derived (Figure 1D). The mean MPOD was within 2.5% of the specified value. For human subjects, we present FAF images and the derived MPOD profiles (an example is shown in Figure 2) for the central 5° around the fovea.

Conclusions : A slit-scanning ophthalmoscope can perform objective FAF measurements of MPOD in a single perceived flash, through non-dilated pupils. This gives encouragement that such a method can be practical for screening, for example for risk of age-related macular degeneration. Validation of such an approach for in vivo use will require careful consideration of confounding effects, such as secondary fluorophores and photobleaching.

This is a 2021 ARVO Annual Meeting abstract.

 

Figure 1. (A) OD of test phantom; (B,C) FAF images of test phantom; (D) Derived OD profile at 460 nm.

Figure 1. (A) OD of test phantom; (B,C) FAF images of test phantom; (D) Derived OD profile at 460 nm.

 

Figure 2. (A,B) FAF images of a human subject; (C) Derived spatial distribution of MPOD at 460 nm.

Figure 2. (A,B) FAF images of a human subject; (C) Derived spatial distribution of MPOD at 460 nm.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×