 Gamma Knife versus
CyberKnife
Setting the Record Straight
Competition to treat benign and malignant brain lesions, vascular
malformations, and functional conditions with stereotactic radiosurgery
(SRS) has increased dramatically in recent years. All-in-one systems
like the Accuray's CyberKnife are aggressively positioning themselves
as being comparable to the Leksell Gamma Knife® in effectiveness and
efficiency.
As one of the earliest and most experienced Gamma Knife centers in
the world, we at the  University of Virginia
wish to address the competing LINAC based technologies such as
Cyberknife.
Gamma Knife surgery is the gold standard for the
treatment of intracranial pathology. Its clinical efficacy has
been documented across nearly four decades, with more than 400,000
cases treated worldwide providing the data for 2,000+ publications in
peer-reviewed medical literature. It is used as the performance
standard against which other technologies (such as CyberKnife) are
measured.
Perhaps the easiest way to state our case is to compare, point for
point, the Gamma Knife with the CyberKnife.
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Gamma
Knife
|
CyberKnife
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- 201 source cobalt unit designed exclusively for non-invasive brain
surgery, with 100x less radiation to the body than the Cyberknife,
thereby decreasing the chance of radiation induced complications.
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- Single source linear accelerator with robotic arm to compensate for
patient movement during treatment; not exclusively used for
intracranial SRS
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- Radiologic accuracy better than 0.3mm
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- 1 mm accuracy; dose outside the target area is 2-6x greater than
with GK
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- Rigid immobilization to prevent head movement using a lightweight
stereotactic head frame fixed to the outer skull. Provides exact
MR and CT correlation from planning to radiosurgical delivery in
3D.
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- Non-rigid immobilization reduces head movement by using a
thermoplastic face mask that is shrink-wrapped to the table during
treatment. Provides relative MR and CT correlation from planning
to treatment delivery in 3D. The moving target and moving
radiation source are inherently less accurate that a fixed target and
fixed source.
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- Treatment delivered during one session
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- Single or multiple treatments, possibly over a period of days to
weeks
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