The use of advanced technology, simulation and visualization in neurosurgery has been
an evolving field in the past 5 years. Navigation assisted neurosurgery and now simulation
integrated neurosurgery, has shown to be a highly useful step in the preoperative
phase.
The neurosurgical team prepared the patient for computer-assisted resection creating
a 3D-simulated view of the patient’s anatomy. Standard volumetric sequence isotropic
MRI and contrast CT sequences were obtained, loaded, and fused to one another using
Brainlab’s curve and Surgical Theater’s SNAP technology. This was followed by segmentation
of operative structures. Where MRI data can be used to extract information about soft
tissue anatomical structures and pathology where CT and CTA data can help to define
boney and vascular structures.
During preoperative planning we employed Brainlab Cranial Software for navigation
and used the Smartbrush element to create objects of interest. The Smartbrush tool
is a computer-assisted paintbrush that allows the user to outline the critical structures
from the patient’s radiographic data. These objects are then uploaded into the navigation
platform and used in a heads up display (HUD) configuration with an intraoperative
microscope. Here, the objects of interest were overlaid onto the patient’s anatomy
through the eyepieces in real time. Stereotactic navigation defines the coordinate
frame for the microscope. The registration information may also be exported to a 3D
simulation platform to help increase visualization and situational awareness during
surgery.
In a few specific cases tumor located in the anterior skull base involved one or more
of the following: optic nerves, optic chiasm, carotid artery, or basilar artery. Reviewing
the simulation during the preoperative planning phase allowed for an enhanced ability
to make decisions about surgical approach.
Case 1: A 54-year-old female presented with a tuberculum meningioma compressing the optic
nerve. During the preoperative planning phase the team was able to visualize the transbrow
approach to confirm simulated findings.
Fig. 1
Fig. 2
Case 2: A 52-year-old female presented with a known tuberculum sella meningioma causing vision
loss. Patient underwent a bicoronal incision, during the procedure critical structures
(carotid artery, and branches of ACA, optic nerves) outlined by HUD were identified
and helped to guide resection with the goal of preserving the left optic nerve which
had been displaced and compressed by tumor. On the left side, the tumor had grown
into the optic canal, between the internal carotid artery and the optic nerve.
Fig. 3
Case 3: A 57-year-old male with a large recurrent pituitary tumor compressing the optic nerve
and surrounding carotid arteries. The case was approach in two parts: both cranial
and endoscopic as determined by the extent of the tumor. Intraoperatively patient
was positioned and transbrow incision was outlined for a minimal exposure that would
allow for access to the area of tumor that was causing vision loss. HUD was utilized
to confirm positioning would allow for appropriate approach to tumor/optic intersection.
Fig. 4
