Dual modality fluorescence confocal and spectral-domain optical coherence tomography microendoscope

Abstract

Optical biopsy facilitates in vivo disease diagnoses by providing a real-time in situ view of tissue in a clinical setting. Fluorescence confocal microendoscopy and optical coherence tomography (OCT) are two methods that have demonstrated significant potential in this context. These techniques provide complementary viewpoints. The high resolution and contrast associated with confocal systems allow en face visualization of sub-cellular details and cellular organization within a thin layer of biological tissue. OCT provides cross-sectional images showing the tissue micro-architecture to a depth beyond the reach of confocal systems. We present a novel design for a bench-top imaging system that incorporates both confocal and OCT modalities in the same optical train allowing the potential for rapid switching between the two imaging techniques. Preliminary results using simple phantoms show that it is possible to realize both confocal microendoscopy and OCT through a fiber bundle based imaging system.

Video-rate structured illumination microscopy for high-throughput imaging of large tissue areas

“…A number of groups have employed fluorescent staining of unfixed tissues followed by optical sectioning microscopy with laser-scanning microscopes (including confocal microscopy and multi-photon microscopy) as a means to obtain high-contrast pathologic images of tissues at the point-of-care [5][6][7][8][9][10]. The fluorescent stains highlight the microanatomy similarly to histological stains, and the rejection of out-of-focus background allows thin optical sections of the intact tissue to be obtained in lieu of thin physical sections.…”

En face coherence microscopy [Invited]

“…Even performed with high numerical aperture objectives, en face OCT can only discriminate two cell populations based on their shapes, but not on their molecular content, or on their function. Fluorescence techniques can reveal or complement the OCT information that is obtained from a cell or a structure [77][78][79][80] using various approaches: single or 2 photon fluorescence, superficial observation or endoscopy [81][82][83][84]. Following similar developments in OCT [85][86][87][88], several multimodal setups associating full field microscopy and various fluorescence techniques have been developed [89][90][91].…”

“…Ideally, two cameras are required for combining FF-OCM and SIM, as technological requirements of FF-OCM and fluorescence cameras are almost opposite. References [79] and [80] have proposed a similar configuration, in which a flip mirror enables acquisition of either an FF-OCT or a SIM image. Thanks to the sequential imaging of the two modalities, there are less spectral limitations for the two modalities combined.…”

Optical configuration of pigmented lesion detection by frequency analysis of skin speckle patterns

“…These optical methods, i.e. 'optical biopsy' methods [22,23], such as fluorescence endoscopy [24], optical coherence tomography (OCT) [25,26] and confocal microendoscopy [27,28], were developed in order to extract a three-dimensional cross section, avoiding the diffuse reflected light. However, these methods are very complicated and heavily depend on the expertise of the researcher.…”