This Conference Presentation, “Translation of a label-free approach to surgical guidance,” was recorded at SPIE Photonics West 2022 held in San Francisco, California, United States.

This Conference Presentation, “Hyperspectral imaging and machine learning for cancer detection and surgery,” was recorded at SPIE Photonics West 2022 held in San Francisco, California, United States.

White-light imaging remains indispensable as the standard of care, from ophthalmoscopy to endoscopy, yet the ability to capture multispectral imaging (MSI) data without changing the instrument form factor would dramatically enhance our visualization of tissue biochemistry. We introduce a custom MSI sensor that combines standard white-light with narrowband imaging and enables quantitative assessment of changes in tissue blood supply. The MSI sensor is realized by patterning a custom filter array atop a CMOS image sensor using a single-step grayscale-to-color lithographic process. By augmenting the ubiquitous Bayer mosaic with complementary narrowband filters, biomedical MSI is achieved using a single image sensor.

Classical fluorescence guided surgery uses long laser pulses to excite fluorescent tracers, only providing the practitioner with 2D information. In this work, we develop and test a 3D imaging technique using LiDAR technology to sense target tissue depths up to 5 mm below the surface. Imaging through highly scattering medium like tissues implies that temporal information used for 3D reconstruction is convolved with diffuse dynamics of the medium. Using diffuse reflectance as an indicator of the medium’s optical properties, correction of the time-of-flight is made possible. Time-of-flight fluorescence imaging, captures intensity as well as temporal profile of fluorescence excited by ultra-short pulses.

5-ALA induced PpIX is increasingly used for guiding brain tumor resection surgery. The current intensity-based approach fails at detecting lower concentrations of PpIX found in low-grade gliomas or the infiltrative edge of glioblastomas. Here, we report the first results in patients of real-time, PpIX fluorescence lifetime measurements using a hand-held fiber probe. Fluorescence from different spectral channels (390/40 nm (Collagen), 470/28 nm (NADH), 629/53 nm (PPIX)), is augmented onto a video stream of the surgical field-of-view to provide intraoperative tumor visualization in real-time. In-vivo data reveals strong contrast between regions of high PpIX accumulation associated with tumor (>8 ns) and healthy brain tissue (<4 ns).

Tumor-specific targeting with fluorescent probes can enhance contrast for identification cancer during surgical resection and visualize otherwise invisible tumor margins. Fluorescent probes derived from nanobodies, the smallest naturally occurring antigen binding molecules, can be used for in-vivo labeling with rapid pharmacokinetics. The present work demonstrates the efficacy of a fluorescent anti-CEA nanobody conjugated to an IR800 dye to target and label patient derived pancreatic cancer xenografts. After intravenous administration, the probe clearly localized to the pancreatic cancer tumors and had a tumor-to-background ratio of 2 or greater by 1 hour. Tumor-specific fluorescent nanobodies are clinically promising molecules for same-day labeling and imaging of tumors.

This Conference Presentation, “Imaging cancer with protease activated optical probes” was recorded at SPIE Photonics West 2022 held in San Francisco California, United States.

Melanoma is the most aggressive skin cancer with the highest associated mortality, early diagnosis ensures high survival rates. Currently, in vivo morphological imaging such as reflectance confocal microscopy (RCM) is associated with high sensitivity but moderate specificity. Addition of molecular imaging using PARPi-FL (PARP1-targeted fluorophore) can improve distinction between malignant/potentially malignant lesions. Towards multimodal imaging in vivo, we first investigated differential PARP1 expression in the spectrum of melanocytic lesions. Higher PARP area positivity and intensity were found in melanoma as compared to benign nevi. Thus, PARPi-FL in association with RCM can potentially improve melanoma diagnosis non-invasively in patients.

In this work, we compare the accuracy of radiological axial imaging-guided surgical navigation (computed tomography (CT) and magnetic resonance (MR)) with and without the use of subsurface fluorescence guidance. We tested this by utilizing a validated tissue-simulating phantom model of various tissue types with a randomly placed tumor inclusion and then dissecting the phantoms using different combinations of navigation modalities. Results demonstrated that fluorescence guidance improves the accuracy of radiological imaging-guided surgery with significant improvements in margin consistency and tumor inclusion alignment.

This Conference Presentation, “Between two tissues: fluorescent guided surgery to improve clinical outcomes,” was recorded for Photonics West BiOS 2022 On Demand.

This Conference Presentation, “Utilization of near infrared nerve-specific fluorescent contrast agents as an intraoperative assessment methodology for nerve damage,” was recorded for Photonics West BiOS 2022 On-Demand.

This Conference Presentation, “Towards clinical translation of paired-agent imaging for FGS” was recorded for Photonics West BiOS 2022 On-Demand.

This Conference Presentation, “Molecular and image-guided neurosurgery: the Dartmouth experience,” was recorded for Photonics West BiOS 2022 On-Demand.

This Conference Presentation, “Clinical development through phase III in fluorescence-guided surgery: the story of SGM-101, an anti-CEA antibody conjugate, paving the way for a new wave of surgical products” was recorded at SPIE Photonics West 2022 held in San Francisco, California, United States.

This Conference Presentation, “Intraoperative PSMA florescence: guided, robotic radical prostatectomy: results of a phase one study,” was recorded at SPIE Photonics West held in San Francisco, California, United States.