Читать книгу Small Animal Laparoscopy and Thoracoscopy онлайн

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ECE is currently used in small animal endoscopy (i.e. gastrointestinal, respiratory, and urinary systems) and MIS (laparoscopy and thoracoscopy). Enhancement of different vascular patterns, surface contrast, and elimination of edge shadowing allow surgical procedures to be performed with higher levels of accuracy compared to previous standard video imaging systems [18, 19].

Fluorescence is the property in which certain molecules (fluorochromes) emit fluorescent radiation when excited by a laser beam or exposed to near‐infrared light (NIR) at specific wavelengths. Once the light energy is absorbed by the fluorochrome's organic molecules, an excitation of delocalized electrons from ground state to a higher energy level occurs. Upon return from the excited singlet state to the ground state, energy is emitted in the form of photons, reaching the observer's eye as fluorescence of a specific wavelength.

Fluorescence image‐guided surgery (FIGS) is a medical imaging technique that uses fluorescence to detect properly labeled structures during surgery. Its purpose is to guide the surgical procedure and provide the surgeon a real‐time view of the operating field. When compared to other medical imaging modalities, FIGS is cheaper and superior in terms of resolution and number of molecules detectable. As a drawback, penetration depth is usually very poor (100 microns) in the visible wavelengths, but it can reach up to 1–2 cm when excitation wavelengths in the near infrared are used. FIGS is performed using imaging devices with the purpose of providing real‐time simultaneous information from color reflectance images (bright field) and fluorescence emission. One or more light sources are used to excite and illuminate the sample. Light is collected using optical filters that match the emission spectrum of the fluorophore. Imaging lenses and digital cameras are used to produce the final image [20–22].