Laparoscopic laser speckle contrast imaging for the demarcation of lung segments

Lung cancer remains to be the leading cause of cancer-related deaths
worldwide1. The current standard-of-care for small lung cancer is a total
lobectomy. Albeit effective with respect to the radical excision of the tumour,
the substantial loss in lung tissue may be clinically relevant, especially in
combination with frequently co-existing lung diseases. Thoracoscopic
segmentectomy is a combination of adequate oncological resection with
lung-tissue-sparing properties and is being increasingly used because of its
several advantages compared with lobar resections. By defining the segment that
has to be excised pre-operatively, the key to successful pulmonary
segmentectomy is to subsequently intraoperatively recognize the intersegmental
planes correctly. The conventional and most common method uses a ventilation
method (inflation/deflation technique). With the increasing availability of
laparoscopic imaging systems, indocyanine green (ICG) fluorescence imaging is a
more advanced method to determine intersegmental planes. The major limitation
is the use of an exogenous contrast agent. After injection, the ICG only has
very limited *imaging time window* (minutes) in which the images can be used to
determine the intersegmental planes. Furthermore, the use of dye limits
repeatability of measurements due to rest ICG, the extra operating room time
required for the injection, wash-in and wash-out of the dye as well as change
of camera settings. These limitations leave room for new technologies and
improvements. We hypothesized that a laparoscopic laser speckle imaging device
could overcome the limitations of ICG-fluorescence imaging and could thus be a
very useful addition in intersegmental plane detection. PerfusiX-Imaging (LIMIS
Development BV, Leeuwarden, The Netherlands) is such a laparoscopic laser
speckle contrast imager that has been developed in the Medical Centre
Leeuwarden since 2014. LSCI has never been used to identify intersegmental
planes, however, based on the similarities between LSCI and ICG-fluorescence,
this novel imaging approach is thought to be effective and potentially could be
used as a standard-of-care.

In this trial we will study the utility of PerfusiX-Imaging for the
identification of intersegmental planes during thoracoscopic segmentectomy.

The current study is a prospective, observational single-centre study in the
Medical Center Leeuwarden.

The total surgery is expected to take 5 minutes longer. There are no known
risks. Patients did not directly benefit from this study. The surgery proceeds
as normal, with the addition of the additional perfusion measurements. During
the operation, no decisions are made on the laser speckle images.