Dual axes confocal microendoscope

Abstract

Biomedical research truly needs new advances in imaging. Existing modalities of in vivo imaging, such as magnetic resonance imaging or ultrasound, lack the spatiotemporal resolution required to image the fundamental building block of living tissue. By contrast, existing high-resolution techniques for imaging cells and their sub-cellular features are technologies that are best suited for in vitro experiments in tissue slices. Yet, the ability to make direct connections between human pathological symptoms/behavior and the underlying cells and molecules responsible for such behavior requires in vivo techniques that can image cellular constituents. Our group research aim is to develop novel high-resolution optical endoscopes to satisfy unmet needs in the clinical environment. These differ from medical endoscopes, which are generally larger and designed to image macroscopic abnormalities. Most importantly, this novel optical endoscopic imaging might suggest new approaches to disease diagnosis and treatment. This talk will be focused on the development a novel confocal imaging modality integrated with microelectromechanical systems (MEMS) technology and their imaging applications. Confocal microscopy is an attractive tool for three-dimensional (3-D) imaging due to its optical sectioning property. Conventional single-axis confocal (SAC) microscopes have a tradeoff between resolution, field of view, and objective lens size, since a high numerical aperture (NA) lens is needed for sufficient resolution, and a long focal length is needed for a large FOV and working distance. A dual-axes confocal (DAC) microscope architecture has been proposed utilizing two overlapping low NA beams, which effectively decouples these tradeoffs. The other important advantage is the ability to achieve a much superior optical sectioning compared to the SAC design. The microscopes are miniaturized into two form factors (5 mm and 10 mm diameter). The imaging demonstrations of the probes were on both ex vivo and in vivo from mice and human for cancer oncology and genetic research. © 2012 Springer Berlin Heidelberg.