Journal: Science Advances

Article Title: Longitudinal high-resolution imaging through a flexible intravital imaging window

doi: 10.1126/sciadv.abg7663

Figure Lengend Snippet: ( A ) Photograph of a PDMS intravital imaging window. ( B ) 3D drawing and cross-sectional view of the window; 18 mm in diameter (ld) and 2 mm in height (Ih). The device allows imaging with an angled objective (Obj) up to 118° over a working diameter (Wd) of 9 mm. At 200 mg, the PDMS window is at least 3× lighter than conventional titanium/glass windows. The angle of the skin groove (1) protects the window frame from damage and removal by the mouse. To promote healing and immobilization of the window, equally spaced holes surround the structure (2). An injection port, 0.7 mm in diameter (3), is positioned on the side of the window. ( C ) Light intensity measured through glass (red) or PDMS (green) windows relative to air. ( D to F ) PSF analysis comparing glass (red) and PDMS (green). Graphs display calculated full width at half maximum (FWHM) values in (D) X axis, (E) Y axis, or (F) Z axis over depth. Comparison between glass and PDMS FWHM at each depth was performed using a Mann-Whitney test ( n > 20 measurements per section). ( G ) Chromatic aberration analysis of the indicated color pairs through glass (red) or PDMS (green) windows. Both glass and PDMS in every color pairs are significantly lower than ratio R/Ref < 1, indicative of colocalization ( P < 0.01, one-sample Wilcoxon text). No significant differences were observed between glass and PDMS for all color pairs ( P > 0.05, Mann-Whitney test). ( H ) Mapping of the microgrid deformations arising from glass coverslips, relaxed, or stretched (to 200%) PDMS windows compared to the microgrid alone. Vectors of deformation were calculated on each dot of the grid to generate 2D maps [md, measured deformation norms (μm); vectors represented at 50×]. Deformations induced by glass coverslips (0.037 ± 0.019 μm SD), relaxed (0.076 ± 0.031 μm SD), and stretched (0.099 ± 0.043 μm SD) PDMS windows were all below the lateral imaging resolution (0.161 μm per pixel) and the inherent aberrations of the optical system. ns, nonsignificant; * P < 0.05; ** P < 0.01; *** P < 0.001; and **** P < 0.0001. All source data are provided in data files S2 and S3.

Article Snippet: To measure morphological aberrations that may arise from an uneven window surface, we imaged a microgrid (Argolight SLG-075, pattern B) using a laser excitation wavelength of 405 nm through either water only (uncovered), glass, relaxed PDMS, or stretched (to 200%) PDMS (wavy) window in duplicates.

Techniques: Imaging, Injection, Comparison, MANN-WHITNEY