Cirs ZEUS 008Z, User Manual

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The integration of MR imaging in radiation therapy facilitates real time motion
management.
The CIRS Zeus MRgRT Motion Management QA phantom is designed to
address such needs. Zeus is MR Safe due to the use of piezoelectric motors
and non-ferro-magnetic materials. The two piezoelectric motors move a cylin-
drical insert, which contain a tracking target, through a gel/liquid fillable body
by rotating it independently from the motion in the Inferior-Superior direction.
The moving insert contains an organic shaped target (tumor) filled with gel,
which is surrounded by the same background gel used to fill the body. The
body represents a heterogenous background due to simulated lungs, liver,
kidney and spine. The simulated organs are anatomical in shape and have a
life-like spatial relationship. They are filled with gels that provide contrast in CT
and MR versus the background gel, which fills the void between the organs.
Besides imaging, all organs, except for the lungs, offer ion chamber dosimetry
cavities, which allow for completing an entire QA process; from imaging to
planning to verification of dose delivered.
Zeus is designed as a single unit with a piezo actuator fixed permanently to
a base plate on which the MRI body “snaps”. This allows for quick setup, re-
moval, filling, and storage purposes. The phantom’s base plate has machined
slots on the bottom, which allow for the use of indexing bars for precise and
repeatable/reproducible phantom-MRI (MRI-Linac) alignment.
Overview
Key Features
• Non-ferromagnetic materials
=> MR safe
• Allows for positioning within
magnet bore due to piezo
electric motors
•
Organic shaped organs at
risk and moving target
• Can be imaged in MRI, CT,
and hybrid systems
• Ion chamber dosimetry in
liver, kidney, spine and
moving target
• Calculate beam latency for
each breathing cycle and as
an average of all executed
cycles without the need of an
external oscilloscope.
• 3D tissue equivalent spine for
bone landmark