Fluorescent Imaging
Exploring different interests and career paths, I spent the summer after my freshman year of college working in a biomedical optics lab at Dartmouth. Throughout the summer, I manufactured phantoms to analyze the imaging capabilities of several different existing technologies, resulting with a second author role in a published paper.
Motivation
Fluorescence-guided surgery is a newer method of imaging that provides advantages in discerning cancer margins and distinguishing tissue oxygenation. However, as use of this technology increases, there lacks a consistent way to standardize all the various fluorescent imaging tools.
Manufacturing Phantoms
Fluorescence-guided surgery is a newer method of imaging that provides advantages in discerning cancer margins and distinguishing tissue oxygenation. However, as use of this technology increases, there lacks a consistent way to standardize all the various fluorescent imaging tools. Using 3D-printed molds shown below, I manufactured two types of phantoms—one of wells filled with varying fluorescent agent concentrations within polyurethane mixtures and another with varying tissue depths.
Each hole in the phantom had a specific agent concentration and tissue depth to image. In perfecting this process, improvements included selecting IR 125 dye as the fluorescent agent because of its similar properties to ICG (a commonly used fluorescent dye for surgery), adjusting polyurethane degassing time, and attempting different mixing methods to decrease air bubbles in the hardened polyurethane.
Imaged fluorescent phantom
The Results
Using these phantoms, I tested and analyzed the capabilities of three fluorescent imaging tools: Stryker's SPY Elite, PerkinElmer's Solaris, and LI-COR's Odyssey. For each imaging system, we found the noise floor, usable range, and saturation point of its imaging capabilities.
Mean Imaged Pixel Value of Varying Concentrations of IR 125 Dye
Using these phantoms, I tested and analyzed the capabilities of three fluorescent imaging tools: Stryker's SPY Elite, PerkinElmer's Solaris, and LI-COR's Odyssey. For each imaging system, we found the noise floor, usable range, and saturation point of its imaging capabilities.
In addition to the phantoms with wells of fluorescent agent, I also manufactured phantoms for testing the system resolution.
Production
Finally, with the analysis and testing finished, I produced several finished phantoms to ship to clients to test their own imaging systems. The final product also included a well for testing light scattering capabilities and another for testing absorption capabilities.