This work presents the design and implementation of an endoscopic probe for point-of-care diagnosis of bladder cancer, with an outer diameter of 4.5 mm that allows for in-vivo usage. This triple-modality device can deliver volumetric OCT images, optoacoustic tomograms, and single point Raman spectroscopy that target complementary biomarkers. The probe features a piezo-based fiber scanner, which delivers the illumination or excitation light for all modalities, with a maximum Field of View of 1.6 mm. The same path is used for light collection for OCT imaging. A separate fiber is used for detection of the Raman signals, while two additional fibers with microcavity tips sense the ultrasonic waves for optoacoustic tomography. A hyperchromatic micro-optical objective provides a working distance optimized for each modality. The probe housing is produced by selective laser-induced etching of fused silica.
Non-linear endoscopic imaging probes allow for in-vivo, label free tissue histology and thus bring tumour treatment to a new level providing accurate, real time diagnostics. Here we present an endomicroscopic imaging probe for coherent anti-Stokes Raman scattering (CARS) imaging based on a fiber piezo scanner at the distal side of the probe. One of the main hurdles in the implementation of CARS imaging in all-fiber solutions is the generation of a background four-wave-mixing (FWM) signal within the delivery fiber by the Stokes- and pump lasers involved in the process of generation of the nonlinear image. We developed and realised a novel solution based on a silica double-core double-clad (DCDC) fiber, which allows a separate guiding of the exciting Stokes- and pump laser radiation in two separate cores of the delivery fiber. The optical design of the endoscopic probe allows perfect overlap and focusing of the Stokes and pump lasers across the full field of view of the probe.
A miniature endomicroscope is presented that combines a large field-of-view (up to 1.7 mm) for OCT-imaging and a high-resolution mode with 360 μm field-of-view (NA = 0.5) for multi-photon fluorescence or OCT imaging. The 4.7x magnification variation is achieved by the axial positioning of an inner micro-optical lens group using an integrated electro-magnetic z-actuator. A reverse fiber-optic piezotube-scanner with minimized length is employed for the image acquisition by resonant spiral scanning. With the probe diameter of 2.7 mm and a rigid length of about 60 mm, the approach may pave the way to clinical applications of these two modalities in a single probe.
We demonstrate a flexible stand-alone, minimally invasive video-endomicroscope with an outer diameter of
1.6 mm and a length of the rigid tip of 6.7 mm that enables surgeons and biologists to image hardly accessible
regions in-vivo in epifluorescence mode. The 60 mg light device improves state-of-the-art objectives by a
double deflection approach using a side-fire fiber in combination with spherical microlenses, GRIN-lenses
with a specific adapted gradient index profile and an extremely miniaturized chip-on-the-tip camera to
achieve an excellent imaging quality. A high NA of 0.7 enables the observation of subcellular features within
the entire field of view with a diameter of 183 μm, assure a bright and high-contrast image and promise a
good overview during the intervention. Ex-vivo measurements of biological samples confirmed the
functionality of the probe.
Endomicroscopic objectives have been used for linear confocal as well as nonlinear quasi-confocal imaging processes for
many years, especially in medical and neuroscience applications. State-of-the-art devices achieve sub-cellular resolutions by
combining plano-convex lenses with special high-NA silver-doped GRIN lenses and diffractive optical elements for their
chromatic correction. NAs of 0.8 are achieved while keeping the outer diameter of the mounted objective as thin as 1.4 mm.
Recently developed designs correct two major drawbacks of the state-of-the-art devices and are presented in comparison with
their precursors. With these developments, the diffraction-limited field of view is increased by 350% in diameter for
monochromatic corrected devices and even more for the polychromatic corrected ones. Besides, solutions for chromatic
corrected objectives are presented which avoid diffractive optical elements and rather make use of achromatic lenses. The
design concepts of those recently developed objectives are presented here and corresponding prototypes are evaluated by
confocal and quasi-confocal experiments as well as by wavefront measurements.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.