Endoscopy – our experience about what to do /
not to do in the first cases
Peter Senn, M.K. Schmid (Luzern)
Purpose: To study
indications and complications of endoscopy techniques, used by
experienced vitreous surgeons but endoscopy beginners, in a clinical routine
setting.
Methods: Prospective analysis of our first 23 cases in regard of complications
and technical problems.
Technique and results: Endoscopy was combined with a pars plana vitrectomy
under the BIOM. Main clinical indications were: primary focal corneal
opacities, secondary visualization problems under air due to a complex
anterior segment situation, search for the source of recurrent bleeding
in the outmost periphery, endocyclophotocoagulation. We used a 20g GRIN
- endoscope with a 110° observation angle or a 19g GRIN -endoscope
with 100° observation angle and an integrated laser fiber. A 60°
optics with laser fiber was only used once for retina-laser coagulation,
it was not considered to be useful (narrow observation field when finally
close enough to perform laser). When performing laser under air, the combined
endoscope with laser fiber tended to fail, due to "coaling"
the optics with burned tissue - a minor problem when using bimanually
a laser fiber and the endoscope separately. A bit to our surprise, the
OR- staff accepted the new tool with interest, having no problems to get
it ready whenever it was required intraoperatively (maybe some of them
thinking back at the times as technical assistants in "real big surgery"
with real big endoscopes). Daily-contact lenses were found helpful for
the intraoperative correction of a myopic surgeon, usually not wearing
glasses at the microscope. Our major concerns was, to cause iatrogenic
damage with the new device - this showed to be no problem: an at least
partial orientation of the tip in the globe during surgery was easy by
using the BIOM. Following prior recommendations to "use it for training
like a light-pipe" ended up in the painful and expensive experience
of three broken tips, the 20g tool being especially vulnerable towards
inadvertent bending.
Conclusions: In certain cases endoscopy is helpful in complex cases. The
learning curve for experienced vitreoretinal surgeons is short, the risk
for iatrogenic damage is minimal. Endolaser under air should be performed
bimanually with separate laser/endoscope fibers. Don't use your GRIN-endoscope
as a light pipe. For the beginning, an additional observer of the video
screen to warn in case of stressing the optics may wall safe costs. A
100° optics is ideal as a standard device, the 19g is more solid than
20g, it does not really interfere with 20g vitrectomy and is therefore
preferable.