We propose a handheld projective imaging device for orthotopic projection of near-infrared fluorescence images onto target biological tissue at visible wavelengths without any additional visual aid. The device integrates a laser diode light source module, a camera module, a projector, an ultrasonic distance sensor, a Raspberry Pi single-board computer, and a battery module in a rugged handheld unit. It is calibrated at the detected working distance for seamless coregistration between fluorescence emission and projective imaging at the target tissue site. The proposed device is able to achieve a projection resolution higher than 314 μm and a planar projection bias less than 1 mm at a projection field of view of 58 × 108 mm2 and a working distance of 27 cm. Technical feasibility for projective imaging is verified in an ex vivo model of chicken breast tissue using indocyanine green as a fluorescence agent. Clinical utility for image-guided surgery is demonstrated in a clinical trial where sentinel lymph nodes in breast cancer patients are identified and resected under the guidance of projective imaging. Our ex vivo and in vivo experiments imply the clinical utility of deploying the proposed device for image-guided surgical interventions in resource-limited settings.
Sentinel lymph node biopsy is important in the early stage breast tumor resection surgery. Its results will determine if the axillary lymph node dissection (ALND) will be conducted afterwards. For locating sentinel lymph nodes, indocyanine green (ICG) has been widely used with a near infrared (NIR) camera to image its fluorescence. However, surgeons need to watch a screen beside the operating table to see the fluorescence, with their hands operating on the surgical site. We developed a navigation system that projects the invisible fluorescence back to the surgical site visibly in real-time. The system introduces a co-axial optics design to guarantee the projection accuracy. Phantom experiments are conducted to assess the projection resolution and accuracy of the system. Animal experiments with three mice show a good system performance and its preclinical feasibility. Furthermore, the system is tested in a clinical trial of ninety breast cancer patients in three hospitals in China. ICG and methylene blue (MB) is subcutaneously injected separately into the areola at 3-4 points to get both fluorescent and visible contrast, for further comparison. The navigation process is compared with a commercialized NIR imaging system. The results show a 100% detection rate of sentinel lymph nodes and a good consistency with the methylene blue and the commercialized imaging device. The experiments demonstrate good clinical feasibility of the co-axial projection system.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.