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Title: A posterior approach to correct for focal plane offsets in
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lattice light sheet structured illumination microscopy
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Yu Shi,
a
Tim A. Daugird,
b
Wesley R. Legant,
a,b,*
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a
Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State
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University, Chapel Hill, USA
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b
Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, USA
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Abstract
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Significance:
Lattice light sheet structured illumination microscopy (latticeSIM) has proven highly
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effective in producing 3D images with super resolution rapidly and with minimal photobleaching. However,
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due to the use of two separate objectives, sample-induced aberrations can result in an offset between the
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planes of excitation and detection, causing artifacts in the reconstructed images.
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Aim:
We
introduce a posterior approach to detect and correct for the axial offset between the excitation
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and detection focal planes in latticeSIM and provide a method to minimize artifacts in the reconstructed
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images.
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Approach:
We utilized the residual phase information within the overlap regions of the laterally shifted
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structured illumination microscopy (SIM) information components in frequency space to retrieve the axial
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offset between the excitation and the detection focal planes in latticeSIM.
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Results:
We validated our technique through simulations and experiments, encompassing a range of
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samples from fluorescent beads to subcellular structures of adherent cells. We also show utilizing transfer
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functions with the same axial offset as that which was present during the data acquisition results in
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reconstructed images with minimal artifacts and salvages otherwise unusable data.
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Conclusion:
We envision that our method will be a valuable addition to restore image quality in latticeSIM
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datasets even for those acquired under non-ideal experimental conditions.
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Keywords: Fluorescence microscopy, Super resolution microscopy, Lattice light sheet microscopy,
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Structured illumination microscopy
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*Corresponding Author, Email: legantw@email.unc.edu
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Introduction
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Lattice light sheet microscopy (LLSM) has been widely applied in biological imaging across various scales,
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spanning from biomolecules to embryos
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. This technique offers several advantages over epifluorescence
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or confocal microscopy, including minimal out-of-focus fluorescence, reduced photobleaching and
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phototoxicity, and enhanced imaging speed. By utilizing the interference pattern from multiple beams,
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LLSM improves beam uniformity and axial resolution compared to Gaussian beams
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. Typically, to ensure
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uniform sample illumination and maximize imaging speed, lattice light sheets are laterally dithered to
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average out modulations due to the interfering beams. However, by stepping the lattice in discrete
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increments rather than dithering, the same light sheet can be utilized for super resolution SIM yielding
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improved lateral and axial resolution
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. LatticeSIM also more thoroughly fills out the optical transfer
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function (OTF) axially compared with dithered lattice illumination which results in better image quality.
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However, due to the fixed objective orientation and the lower numerical aperture (NA) of the excitation
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was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission.
The copyright holder for this preprint (which
this version posted April 26, 2024.
https://doi.org/10.1101/2024.04.26.590138
bioRxiv preprint