Super-resolution retinal imaging using optically reassigned scanning laser ophthalmoscopy

Abstract

Super-resolution optical microscopy techniques have enabled the discovery and visualization of numerous phenomena in physics, chemistry and biology1,2,3. However, the highest resolution super-resolution techniques depend on nonlinear fluorescence phenomena and are thus inaccessible to the myriad applications that require reflective imaging4,5. One promising super-resolution technique is optical reassignment6, which so far has only shown potential for fluorescence imaging at low speeds. Here, we present novel advances in optical reassignment to adapt it for any scanning microscopy, including reflective imaging, and enable an order of magnitude faster image acquisition than previous optical reassignment techniques. We utilized these advances to implement optically reassigned scanning laser ophthalmoscopy, an in vivo super-resolution human retinal imaging device not reliant on confocal gating. Using this instrument, we achieved high-resolution imaging of living human retinal cone photoreceptor cells (determined by minimum foveal eccentricity) without adaptive optics or chemical dilation of the eye7.

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Fig. 1: Simulation of the reassignment procedure and resulting resolution enhancement.
Fig. 2: ORSLO schematic.
Fig. 3: Wide-field versus ORSLO imaging of a 1951 USAF test target.
Fig. 4: Single-frame comparisons of WFESLO and ORSLO.
Fig. 5: WFESLO versus ORSLO retinal image mosaics.

Code availability

The code used in this study is available at http://github.com/tdubose/ORSLO.

Data availability

The data that support the findings of this study are available from the corresponding author on reasonable request.

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Acknowledgements

The authors thank K. Zhou and R. Qian for assistance. This research was supported in part by a grant from the National Institutes of Health (R21-EY027086).

Author information

F.L. and T.B.D. designed and constructed the optical system and drafted the manuscript. T.B.D. collected and analysed data. S.F. and J.A.I provided overall guidance to the project, reviewed and edited the manuscript, and obtained funding to support this research.

Correspondence to Joseph A. Izatt.

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This file contains more information on the work and Supplementary Figures 1–7.

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DuBose, T.B., LaRocca, F., Farsiu, S. et al. Super-resolution retinal imaging using optically reassigned scanning laser ophthalmoscopy. Nat. Photonics 13, 257–262 (2019). https://doi.org/10.1038/s41566-019-0369-7

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