Background: The pineal region is an anatomically complex and deeply situated with a tight neurovascular
network. Standard microsurgical approaches to this area have been associated with
major neurological deficits, deep venous infarction, and brain stem dysfunction. We
investigate a series of 3D endoscope-assisted transtubular approaches to the pineal
region approaches using a minimally invasive tubular retractor system.
Methods: Supracerebellar-infratentorial, including the median, paramedian and extreme lateral
variants, and occipital transtentorial approaches were performed on five preserved
cadaveric heads (10 sides) injected with colored latex. A ViewSite Brain Access System
(Vycor Medical, Inc., Boca Raton, Florida, United States) of tubular retractors was
used. Minicraniotomies or 2- to 3-cm burr holes were fashioned for each specimen with
the aid of neuronavigation (Brainlab AG, Feldkirchen, Germany). The tubular retractor
was introduced under direct 3D endoscopic visualization. Following observation of
crucial neurovascular structures, dissection through the retractor was performed using
bayonetted microinstruments. Surgical exposure and maneuverability were qualitatively
evaluated for each approach by three surgeons using a scoring system.
Results: The pineal region—including the superior and inferior colliculus, origin of the trochlear
nerve, and the quadrigeminal plate—was successfully accessed in all the cases. The
tubular retractor enabled adequate anatomical visualization and provided stable occipital
and cerebellar retraction. Byonetted instruments and bipolar cautery were passed through
the tubular retractor without difficulty, and the tubular retractors applied rigid,
constant, and equally distributed pressure onto the impacted surfaces. The technique
facilitated dissection of the neurovascular structures within the pineal region.
Conclusion: An endoscope-assisted transtubular approach to this region is both safe and effective
for the management of pineal lesions, though the use of routine retractors and their
potential complications, in some cases, cannot be avoided. Further clinical studies
are necessary to determine potential complication rates.
