Augmented microscopy: real-time overlay of bright-field and near-infrared fluorescence images

Abstract

Abstract. Intraoperative applications of near-infrared (NIR) fluorescent contrast agents can be aided by instrumentation capable of merging the view of surgical field with that of NIR fluorescence. We demonstrate augmented microscopy, an intraoperative imaging technique in which bright-field (real) and electronically processed NIR fluorescence (synthetic) images are merged within the optical path of a stereomicroscope. Under luminance of 100,000 lx, representing typical illumination of the surgical field, the augmented microscope detects 189 nM concentration of indocyanine green and produces a composite of the real and synthetic images within the eyepiece of the microscope at 20 fps. Augmentation described here can be implemented as an add-on module to visualize NIR contrast agents, laser beams, or various types of electronic data within the surgical microscopes commonly used in neurosurgical, cerebrovascular, otolaryngological, and ophthalmic procedures.

Intraoperative brain tumor resection with indocyanine green using augmented microscopy

“…To address this challenge we introduced augmented microscopy, a multimodality imaging system, driving a technological paradigm shift in image-guided surgery. 17 Here, we present augmented microscopy in combination with ICG contrast to enhance visualization and resection of a glioma in a small animal model. 18…”

Real-time, label-free, intraoperative visualization of peripheral nerves and micro-vasculatures using multimodal optical imaging techniques

“…In our rat studies, LSCI could detect both veins and arteries in real-time by GPU accelerated processing, whilst fluorescence imaging only permitted very short display durations in each vessel at one time. Watson et al demonstrated augmented microscopy using near-infrared fluorescence images [60]; their study required exogenous injections of fluorescent dye to visualize target structures, and temporal imaging resolutions were limited. This highlights a significant advantage of our label-free imaging method over conventional fluorescent-agentaided-surgical-guidance and/or traditional surgery relying on surgeons' visual abilities.…”

Microdose fluorescence imaging of ABY-029 on an operating microscope adapted by custom illumination and imaging modules

“…More recently, our group demonstrated hyperspectral imaging of PpIX using a liquid crystal tunable filter enabled system using a similar adapter coupling, but without a custom illumination solution [12]. Other near infrared adaptations to operating microscopes have been reported [13], however, they have similar sensitivity than that provided by the IR800 channel and are therefore not suitable for microdose clinical trials. This work demonstrates a picomolar-sensitive device that serves a generalizable platform for future infrared eIND studies in surgeries indicating the use of an operating microscope.…”