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For new patients, Dr. Herman describes Stereotactic Neurosurgery/IGS in this way: “It’s much like a GPS system
you have in your car or phone. We do images on a patient prior to surgery and upload that data to a computer. The computer monitor is like a GPS satellite. What we hold in our hand, our surgical instruments, are like a car using GPS support to navigate a route. The BrainLab system instrumentation, which includes a specialized optical camera to integrate multiple images into a dynamic 3D view of patient anatomy, allows us to map the brain as we’re doing the operation. Our instruments send signals to the satellite that can be seen on the monitor with the patient images. The brain or skull of the patient is like the world we’re trying to carefully navigate. So we can plan out our approach, before we make an incision, and know exactly where we want to go in the body and, in the case of something like a brain tumor, to know exactly how much we need to remove.”
The Global Positioning System (GPS) concepts behind Image Guided Surgery (IGS) were originally developed for military use to guide missiles to ground targets. GPS has since been adapted to a wide range of (peaceful) consumer and industrial uses for archaeologists, geologists, search & rescue teams, and communications firms.
Stereotactic systems have roots that date back to early 1900’s England. London Neurosurgeon Victor Horsley and Physiologist Robert Clarke first coined the term “stereotaxis” to define a neurosurgery
method utilizing the Cartesian (three-orthogonal axis) coordinate system, to locate points within the brain using external cranial landmarks.
Frame-based stereotactic surgery, created before the advent of computers, uses a frame attached to the patient’s head under local anaesthesia. With Frame-based systems posterior fossa lesions are difficult to target; the frame can limit access to the surgical field; guidance is limited to a single target or only a few targets, and maneuvering the apparatus duringsurgerycanbeunwieldy. Modernstereotaxic integration with computed tomography arrived in 1986, revolutionizing modern medicine for general and multiple surgical specialties.
Frameless Stereotactic Image Guided Surgery, which is what Dr. Herman uses, does not require attaching an external hard frame. Instead of a frame construction, the exterior reference points can consist of either natural anatomic landmarks, skin-applied markers (such as special digitized tape), or bone-implanted markers.The brain is imaged by CT, MRI, PET or angiography to register the internal target points, and the BrainLab software is then used to establish the relationship between the external coordinates, the internal anatomical reference points in the diagnostic images, and their counterpart in the surgical space.
Since both the external reference and the internal target are “seen”, the distance of the target from reference points can be measured and visualized in three dimensions. Surgical components (scalpel, laparoscopic, endoscopic, robotic) can be adjusted to the 3D coordinates of the target, and the target can be accurately approached by the surgeon.
Not only does VCMC’s BrainLab system facilitate surgical preplanning and consultations between members of the care team, it can facilitate remote
communications. The surgeon can interact with the integrated 3D patient images; surgeons can outline tumors and more
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