Abstract
Objective Current transnasal endoscopic techniques for sinus and skull base surgery use a single
endoscope to provide visualization from one perspective curtailing depth perception
and compromising visualization of the instrument–target interface. The view can be
blocked by instruments, and collisions between instruments often occur. The objective
of this study was to investigate the use of multiportal retrograde endoscopy to provide
more accurate manipulation of the surgical target.
Design Maxillary antrostomy and frontal sinusotomy were performed on three different cadavers
by three different surgeons. A zero-degree rigid endoscope was introduced through
the nose for the standard transnasal approach. A flexible endoscope was introduced
transorally, directed past the palate superiorly, and then flexed 180 degrees for
the retrograde view. Videos of the standard transnasal view from the rigid endoscope
and retrograde view from the flexible endoscope were recorded simultaneously.
Results All surgeries were able to be performed with dual-screen viewing of the standard
and retrograde view. The surgeons noted that they utilized the retrograde view to
adjust the location of ends/tips of their instruments. Four surgeons reviewed the
videos and individually agreed that the visualization achieved provided a perspective
otherwise not attainable with rigid transnasal endoscopy alone.
Conclusion High-quality visualization of surgical targets such as the frontal or maxillary ostia
can be challenging with rigid endoscopes alone. Multiportal retrograde endoscopy provides
proof of concept that additional views of a surgical target can be achieved. Additional
work is needed to further develop indications, techniques, and generalizability to
targets beyond those investigated here.
Keywords
sinus and skull base surgery - multiportal - reverse perspective endoscopy - endoscopic
surgery
