Bile duct injury (BDI) during cholecystectomy is a serious surgical complication with
increased risk of early death, serious ongoing morbidities including multiple reinterventions
requiring prolonged and repeated hospital stay, and over a billion dollars in additional
healthcare costs in US each year. The introduction laparoscopic approach has progressively
increased overall laparoscopic cholecystectomy procedure volume, for clearly proven benefits
of minimally invasive approach. However, despite the benefits, minimally invasive approach
has resulted in increased and persistent incidence of BDI up to 4-folds in some reports.
Most major biliary injuries result from unrecognized or unintended perception, either
misidentification or misinterpretation of the common bile or hepatic duct as the cystic duct
or misidentification of an aberrant bile duct. It is increasingly clear that the routine use
of intraoperative cholangiography (IOC) has a significant association with decreased and
earlier intraoperative detection of BDI. The recent 'state of the art consensus conference on
prevention of bile duct injury during cholecystectomy' in 2018 strongly recommended that
documenting the critical view of safety (CVoS) and a liberal use of IOC in anticipated
difficult cholecystectomy are highly recommended steps that can potentially mitigate the risk
of BDI during laparoscopic cholecystectomy (LC) in patients especially with uncertain anatomy
or difficult dissection.
Performing traditional IOC laparoscopically under fluoroscopic guidance however can challenge
surgeons' skills, is time-consuming, and requires a learning curve to interpret images.
Despite well-known and accepted risk factors for difficult cholecystectomies and potential
for BDI, the use of advanced imaging for IOC however remains variable and highly user
dependent. The rationale for selective use of IOC is attributable to the fact that the
prevalence and incidence of BDI are low that an individual practitioner would infrequently
encounter such complication in their daily practice or lifetime of a surgeon to justify a
routine use. This is further compounded by the fact that radiation-based fluoroscopic IOC are
cumbersome to efficient workflow, utility and cost (need for contrast reagent preparation and
injection, potential adverse allergic reactions, risk of radiation exposure, training
requirement, need for large capital equipment, space and cost), and variability in proficient
analysis.
Recent randomized controlled trials using near-infrared fluorescent cholangiography (NIFC)
using indocyanine green (ICG) demonstrated significantly superior visualization of
extrahepatic biliary structures during laparoscopic cholecystectomy to white light (WLI)
alone. Pre-dissection surgeon detection rates on naked eye were significantly higher (> 1.8 -
3.1 folds) with NIFC use for all 7 biliary structures than traditional WLI alone. However,
although similar intergroup differences were observed for all structures, addition of NIFC
did not improve additional detection of cystic duct and cystic duct/gallbladder junction
after dissection has been done. In addition, increased body mass index was associated with
reduced detection of most structures in both groups, especially before dissection.
Interestingly, only 2 patients, both in the WLI group, sustained a biliary duct injury.
ActivSightTM is an FDA-cleared device that combines ICG fluorescence for extrahepatic biliary
visualization and laser speckle contrast imaging (LSCI) for perfusion detection in a
laparoscopic form factor. ActivSightTM allows augmented visualization to any current WLI
laparoscopic visualization system displaying both extrahepatic biliary ICG and microperfusion
over cystic duct and artery. As a non-significant risk device, ActivSightTM has been used in
well over 150 patients for laparoscopic cholecystectomies and bariatric, esophageal, and
colorectal procedures, with proven safety and utility. Moreover, ActivSightTM allows raw
infrared visualization data for advanced analysis and AI/ML model development.
Surgeons/scientists now have segmented and analyzed different procedural phases of LC, and
developed inferencing models and algorithms using artificial intelligence (AI)/machine
learning (ML) based on standard WLI procedural videos. Although AI/ML models recognizing
different phases of LC procedures can be as accurate as 80-95% on limited trained dataset
once structures have been clearly dissected, more relevant and key value would be in
identifying critical structures such as bile ducts and arteries before and during, not after
surgical dissection has been performed. Early detection and identification of these critical
structures before and during dissection of the triangle based on AI/ML trained on computer
vision may aid surgeons in performing more effective and safer LC.
ActivSightTM is an FDA 510(k)-cleared optical imaging system based on monochromatic coherent
light known as Laser-speckle-contrast imaging (LSCI) and represents a label-free imaging
method using coherent monochromatic light where blood flow and tissue perfusion can be
detected. A small imaging module that fits between any existing laparoscope and camera
systems and a separate light source placed along any current commercial system will deliver
objective real-time tissue perfusion and blood flow information intraoperatively. In
addition, ActivSightTM can also effectively display with push of button an ICG-based
visualization of the biliary tree in real time at equivalent or superior to current
commercial products. The innovative form factor of ActivSight enables any laparoscopic system
for ICG-based visualization at a fraction of the cost of current competitor with minimal
disruption to workflow.
ActivInsightTM is a prototype software feature in ActivSightTM that recognizes procedural
phases and critical anatomic structures, namely gallbladder, cystic duct, and cystic artery
during LC using AI/ML-based algorithms. The key difference of ActivInsightTM to other models
reported in the literature is that ActivInsightTM is trained on dataset annotated using ICG
and LSCI in addition to WLI.
In this trial, the investigators propose to first validate and then test the precision and
accuracy of ActivInsightTM in detecting critical phases and structures and compare the
performance of the algorithms to those based on models developed using WLI only and
traditional surgeon's naked eye detection during LC in pre-and mid-dissection phases. To
eliminate any bias, the investigators will connect a secondary screen blinded to the main
operating surgeon screens so that real-time function of the AI/ML is not visible to operating
surgeons, to perform real-time analysis and comparison of routine use of advanced augmented
visualization versus current WLI visualization alone with or without computer vision-based
AI/ML.
