NIR Fluorescence Imaging Systems with Optical Packaging Technology

Abstract

Bioimaging has advanced the field of nanomedicine, drug delivery, and tissue engineering by directly visualizing the dynamic mechanism of diagnostic agents or therapeutic drugs in the body. In particular, wide-field, planar, near-infrared (NIR) fluorescence imaging has the potential to revolutionize human surgery by providing real-time image guidance to surgeons for target tissues to be resected and vital tissues to be preserved. In this review, we introduce the principles of NIR fluorescence imaging and analyze currently available NIR fluorescence imaging systems with special focus on optical source and packaging. We also introduce the evolution of the FLARE intraoperative imaging technology as an example for image-guided surgery.

Intraoperative biophotonic imaging systems for image-guided interventions

“…This fact indicates the importance of NIR fluorescence navigation in laparoscopy endoscopy, thoracoscopy, and robotic surgery when the surgeon has only limited visual ability. This clinical need made the many research groups to integrate NIR imaging systems to the available minimally invasive surgical equipment [12–15]. Now, with the growth and popularity of minimally invasive surgeries, there are many FDA approved commercial devices available for laparoscopy, endoscopy, and robotic surgery.…”

“…The excitation source for open-air imaging systems can be chosen according the spectral bandwidth, solid angle of output beam, light output efficiency, application-dependent regulation, cost, and lifespan [12, 15]. The fluorescence light in the open-air or microscopy surgery can be illuminated via optical fiber or directly from excitation source, but in laparoscopic/endoscopic surgery, the designated optical path should carry NIR excitation as well as white light to the field of view (FOV).…”

“…The fluorescence light in the open-air or microscopy surgery can be illuminated via optical fiber or directly from excitation source, but in laparoscopic/endoscopic surgery, the designated optical path should carry NIR excitation as well as white light to the field of view (FOV). For optimal fluorescence imaging, light sources should be able to illuminate the fluorophore at the center of its peak absorption wavelength through dichroic mirrors and bandpass filters [12, 15]. The most commonly used visible-NIR excitation sources are (1) filtered broadband lamps, (2) laser diodes (LDs), and (3) light-emitting diodes (LEDs).…”

“…Filtered broadband lamps provide an economical option to build fluorescence imaging devices (e.g. absorption/transmission/reflectance spectroscopy and surgical microscopy) [12, 15]. High-pressure arc lamps generate an intense and broad spectrum of light from UV-vis to NIR: 200–600 nm for mercury-arc lamp and 220–750 nm for xenon lamp, while incandescent lamps (e.g.…”

“…Tissue absorption, scattering, and autofluorescence are minimum in the NIR window, thus enabling real-time image-guided surgery [10, 11]. While nuclear imaging provides quantitative depth information due to high gamma penetration, optical fluorescence imaging provides relatively high temporal and spatial resolution [12–15]. It is therefore ideal to develop an integrated imaging system by combining NIR fluorescence and gamma-positron imaging to provide surgeons with highly sensitive and quantitative detection of diseases, such as cancer, in real-time without changing the look of the surgical field.…”