UCLA researchers in the Department of Head and Neck Surgery have developed a novel selective spectral illumination system for optical image-guided surgery.
BACKGROUND:
In oncological surgery, patient prognosis depends heavily on complete tumor removal. Currently, surgeons have to rely on subjective evaluations (e.g. visual appearance) to distinguish abnormal from near-normal tissue because there is no gold standard imaging technique. Optical fluorescence-based imaging techniques are increasingly popular for determining cancerous tissue because conventional imaging techniques (e.g. MRI, PET, CT, and ultrasound) are limited in sensitivity, specificity, speed, and field of view. However, optical imaging tools are problematic because they use all or part of the visible electromagnetic spectrum (380-750 nm). To see these surgical markers, the broad-spectrum lights in the room must be turned off. The surgical oncology community, therefore, still awaits an optimized optical technique that can provide relevant information about surgical markers by purely exploiting inherent differences in tissue.
INNOVATION:
Because ambient light cannot be spectrally conditioned or controlled, a new illumination system must be created to provide illumination to the surgeon and allow for visualization of optical image-based devices. UCLA researchers have created a system of surgical illumination composed of multiple narrow-spectrum emitting LEDs that are independently controlled and responsive to the requirements of many optical image-based devices during surgery. Preferably, such a selective spectral illumination system would be installed in place of every light source in the operating room. During normal illumination, the LEDs of all wavelengths are active, and the system will emit in a fashion analogous to a broad-spectrum device. When an optical imaging device is used that requires a portion of the visible spectrum for its operation, the system will dim or turn off the individual LEDs that emit light in the overlapping wavelengths required by the medical device
POTENTIAL APPLICATIONS:
• Use of optical imaging tools in surgery
ADVANTAGES:
• Allow for human vision and use of optical imaging tools simultaneously
• Allows for precision cancer surgery
• Cost-effective and energy-efficient
• Allow for controllable wavelengths of light
DEVELOPMENT-TO-DATE:
A spectral illumination system has been created and tested.
RELATED PAPERS:
Pellionisz PA, Badran KW, Grundfest WS, St John MA. Detection of surgical margins in oral cavity cancer: the role of dynamic optical contrast imaging. Curr Opin Otolaryngol Head Neck Surg. 2018;26(2):102–107. doi:10.1097/MOO.0000000000000444.
Pellionisz PA, Hu Y, Moon A, Rangwalla K, Pensa J, John MAS. Ratiometric autofluorescence lifetime imaging system standardization and application for head and neck cancer. In: Optics in Health Care and Biomedical Optics IX. Vol 11190. International Society for Optics and Photonics; 2019:1119006. doi:10/ggd8x7.