Microscopic hyperspectral imaging studies of normal and diabetic retina of rats

Abstract

A microscopic hyperspectral imager was developed based on the microscopic technology and the spectral imaging technology. Some microscopic hyperspectral images of retina sections of the normal, the diabetic, and the treated rats were collected by the new imager. Single-band images and pseudo-color images of each group were obtained and the typical transmittance spectrums were extracted. The results showed that the transmittance of outer nuclear layer cells of the diabetic group was generally higher than that of the normal. A small absorption peak appeared near the 180th band in the spectrum of the diabetic group and this peak weakened or disappeared in the spectrum of the treated group. Our findings indicate that the microscopic hyperspectral images include wealthy information of retina sections which is helpful for the ophthalmologist to reveal the pathogenesis of diabetic retinopathy and explore the therapeutic effect of drugs.

Hyperspectral Imaging and the Retina: Worth the Wave?

“…All cited ex vivo microscopy techniques are designed in transmittance mode (Fig. 1B), that is, detectors capture light transmitted through the retina, 27,29,[43][44][45] except for those who used an autofluorescent reflectance mode to study the retinal pigment epithelium (RPE) and inherent fluorophores (as discussed elsewhere in this article). 33,46,47 For in vivo imaging, reflectance mode ( Fig.…”

“…1, B1). [43][44][45] As can be remarked in Table 1, most set-ups that extend their spectrum toward the visible and nearinfrared spectrum (ca. 400-1100 nm) belong to this category.…”

“…26,28,54,57,58 Binning is used to trade off spatial or spectral resolution for light sensitivity. 28,44,70 In the case of spatial binning, for example, charges incident to a 2 × 2 block of pixels can be combined into one 'binned' pixel to improve signal-to-noise ratio, at the cost of halving spatial resolution. A comprehensive discussion of the HSI data analysis techniques goes beyond the scope of this review.…”

“…48 However, as a result of coregistration and realignment, resolution of up to 4 nm can be reached for Fourier based scanning techniques and up to 2 nm for the most commonly used techniques such as LCTF, TLS, and PGP. 27,43,44,48,68,79 The higher resolution reached with the latter techniques comes at the cost of other drawbacks, which have to be considered when selecting the most appropriate HSI technique: LCTF are said to be prone to low optical throughput, and polarization sensitivity, 26,49,54 whereas image artefacts caused by the reflectivity in the mirror facets are noted in dispersion based methods. 76 Additionally PGP are substantially large, making them unsuitable for handheld applications 86 ; however, their short processing time, independence of unfocused background light, and low cost are, in contrast, advantageous.…”

Differentiation of live‐viable versus dead bacterial endospores by calibrated hyperspectral reflectance microscopy

“…Recently, the use of hyperspectral (reflectance) imaging has gained interest in the analysis of microscopic structures, including microbes, tissues and associated constituents (Schultz et al , 2001; Demos et al , 2005; Demos, 2007; Haaland et al , 2007; Li et al , 2007). A review of recent literature has shown diverse application of short‐ and long‐wave microspectroscopy for the study of bacteria, cancer cells, human tissue morphology and general cellular structural analysis, but not for differentiating viable from non‐viable endospores.…”