Introduction
Negative margin status is the most important prognosticator in the
surgical treatment of oropharyngeal squamous cell carcinoma (OPSCC), but
can be challenging to achieve with tumors in poorly visualized
regions.1This can be magnified in transoral robotic surgery (TORS) where haptic
feedback is limited. Fluorescence molecular imaging (FMI) using
near-infrared (NIR) fluorophores has been increasingly used to augment
margin definition and residual tumor detection in vivo for
achieving tumor-free margins.
The NIR dye indocyanine green (ICG), routinely used for FMI, accumulates
in areas of disrupted, permeable endothelium (i.e. neoplastic tissue)
via the enhanced-permeability-and-retention (EPR)
effect.2Additionally, ICG accumulates within tumors due to poorly developed
tumoral lymphatics.
Recently, TORS has advanced the surgical treatment of
OPCSCC.3Unfortunately, prior studies found that ICG failed to identify head and
neck lesions and achieve tumor-free margins during
TORS.4 Our
group previously demonstrated that NIR imaging of ICG injected 24 hours
preoperatively, a novel technique called Second Window ICG (SWIG), with
the VisionSense IridiumTM platform, could be used for
intraoperative identification of head and neck lesions and regional
metastasis.5The current study’s objective was to compare a surgical robot-integrated
NIR system to a dedicated NIR imaging platform for intraoperative
imaging with SWIG.