Efficiency, safety and feasibility of PerfusiX-Imaging for Gastro-Intestinal tissue perfusion assessment in humans.

Any gastrointestinal resection causes inevitable vascular damage, which is not
always evident during an intraoperative clinical
assessment of local intestinal perfusion. However, if left unaltered, impaired
perfusion can lead to anastomotic healing
complications such as anastomotic leakage (AL). Owing to its detrimental effect
on both short and long-term outcomes (e.g.,
increased 30-day mortality risk, worsened oncological prognosis), AL is also
one of the most severe possible complications of
gastrointestinal tract surgery. A significant percentage of patients undergoing
restorative intestinal surgery develop AL, leading to
both considerable morbidity and mortality. Impaired perfusion is one of the key
factors implicated in anastomotic failure. Ensuring
adequate perfusion is an important part of a multidimensional approach to
gradually improving the overall outcome in restorative
intestinal surgery. Thus, there is a need for an objective measure of perfusion
suitable for laparoscopic use.
Today, the most commonly used method for the assessment of tissue perfusion for
the gastrointestinal tract (and in general) is the
mere simple inspection using the surgical eye. However, it is hard to objectify
and the judgement is heavily dependent on the
surgeons* experience. More recently, ICG-fluorescence imaging was introduced in
the surgical theater for the visualization of
gastrointestinal blood flow. Unfortunately, this approach is suboptimal in
effectiveness (Non-flowing blood containing ICG gives the
same signal as flowing blood containing ICG (i.e., lacks objectivity and
specificity for flowing blood)) and it is cumbersome to
efficient workflow (need for contrast agent, reagent preparation and injection,
potential adverse allergic reactions). The use of a dye
limits the user in perfusion visualization duration, repetitiveness and
introduces a lack-time between the need for perfusion
visualization and the actual visualization.
PerfusiX-Imaging is a dye-free method that could simplify, and thus speed up,
objective intraoperative perfusion assessment. The
device is added to the laparoscopic trolley and thereby is able to upgrade any
laparoscopic video system with perfusion imaging
possibilities. In comparison to the current clinical practice of
gastrointestinal tissue visualization, based on the mere visual
inspection by human eye or the cumbersome ICG-based systems, our hypothesis is
that PerfusiX-Imaging delivers safe, precise,
objective and real-time visualization of blood flow and tissue perfusion
intraoperatively during minimally invasive surgery with the
following benefits:
1) Quantitative images: PerfusiX-Imaging is based on the LSCI technology and
thus provides objective information related to tissue
perfusion
2) No contrast agent: PerfusiX-Imaging does not require the use of a contrast
agent. This means the surgeon can visualize
perfusion at any time during surgery, for as long as required and with as many
repetitive measurements are deemed necessary.
3) Real-time: PerfusiX-Imaging will visualize the tissue perfusion in
real-time. This allows the surgeon to manipulate tissue (e.g.,
clamping blood vessels) and visualize the effect on tissue perfusion directly.
(i.e., this is not possible using current technologies)
4) Lower patient risk: The risk of adverse events related to the injection of
contrast agents is eliminated associated with comparable
imaging systems, as PerfusiX-Imaging does not require a contrast agent
5) Usability: PerfusiX-Imaging will visualize tissue perfusion in real-time
without the interruption of the workflow as the visualization
is ready at the press of a button.

The study objective is to evaluate the efficiency of PerfusiX-Imaging compared
to the current state of the art for perfusion
measurements; indocyanine green fluorescence imaging. Also, feasibility and
safety of PerfusiX-Imaging for perfusion visualization
of gastrointestinal anastomoses. The safety will be determined through clinical
assessments and evaluation of any adverse event.
The feasibility will be determined through the technically successful
completion of the perfusion visualization. Patients will be in a
follow-up to 30 days postoperatively monitored for the clinical outcome.

The current study is a single-center, randomized, intervention study in the
Medical Center Leeuwarden.

All patients will undergo the standard-of-care program which includes perfusion
assessment by the surgical eye. In addition to this
standard-of-care, 2D-perfusion maps will be generated of the gastrointestinal
perfusion before the creation of the gastrointestinal
anastomoses using PerfusiX-Imaging perfusion mode in combination with a
proprietary third-party surgical laparoscope or using
ICG-fluorescence imaging depending on group allotment.

Burden
The surgical procedure will be extended by a short amount of time (<5 min).
Risks
PerfusiX-Imaging poses non-significant low safety concerns based on the fact
that the device has no patient contact with a very low
laser output.
Indocyanine green has a low risk profile, but there is a possibility of
developing side effects. Most importantly, in very rare cases, indocyanine
green may cause nausea or anaphylactoid or anaphylactic reactions (<1/10,000).
Benefit
The proposed trial poses minimal risk and maximum potential benefits for
perfusion imaging of the gastrointestinal tract thereby
aiding in better substantiated clinical decision making.