Advanced Intraoperative Fluorescence Imager for Nerve Identification

Physical Sciences Inc., collaborating with Dartmouth College, has been awarded a research program by the National Institutes of Health (NIH) to develop a versatile intraoperative fluorescence imager that can capture highly-specific fluorescence images at any wavelength in the visible to NIR range.

Unintended nerve injury is the major cause of morbidity for many surgeries, especially in soft tissue orthopaedic operations. Distinctive visualization of nerves from adjacent connective and fat tissues remains challenging, and therefore, is the major reason for the possible incidence of surgical nerve damage. Fluorescence guided surgery (FGS) with nerve-highlighting agents has the potential to improve nerve identification. Existing FGS devices are designed for fluorescent agents in the near-infrared or NIR (700 nm to 900 nm), such as ICG and Methylene blue. However, most of the demonstrated nerve labeling agents are in the visible range. Adapting NIR systems to visible wavelengths is not trivial, mainly because of the presence of the strong white light background in the operation room (OR) that overwhelms the weak fluorescence signal.

The key innovation of this technology is the use of spatially modulated illumination to eliminate the negative impact of the ambient light background that is essentially a uniform (in space) continuous wave. A time-gated detection scheme based on a high-speed camera and a low duty cycle pulsed light source will be used to enable efficient rejection of the ambient light background. This R&D project will lead to a reliable solution enabling intraoperative fluorescence imaging in both NIR and visible range, while with little/no susceptibility to ambient light interference. This will promote intraoperative fluorescence imaging procedures to be seamlessly integrated into current clinical workflows for optimal patient outcome.

For more information, contact:

Dr. Nicusor Iftimia
Area Manager, Biomedical Optics Technology
iftimia@psicorp.com
Physical Sciences Inc.
Telephone: (978) 689-0003