QUASAR™ Respiratory Motion Platform

Radiation Therapy technologies, such as IGRT, SGRT and respiratory gating, have led to significant advances in patient treatment. The QUASAR™ Respiratory Motion Platform is a programmable breathing and patient motion simulator for end-to-end quality assurance on motion-guided radiation therapy using your existing phantoms. The Platform’s unique multi-directional motion ability includes superior/inferior translation with an optional lateral hysteresis, creating phase separation between the linear platform and vertical chest wall motion.

Medical Physicists around the world have adopted the QUASAR Respiratory Motion Platform. A balance of simple design and comprehensive testing capabilities has solidified its reputation as an industry-leading tool for respiratory motion management.

Integrate your motion QA with the leaders in SGRT.

The QUASAR Respiratory Motion Platform features a vertical chest-wall platform that is compatible with a number of Surface Guided Radiation Therapy Systems (SGRT), such as: Vision RT, C-RAD, Brainlab, and Varian Identify. Easily import patient-specific waveforms from various motion capture and waveform generating sources. Compatible with the following file formats: VXP, .CSV, .TXT, .DCM, .LOG, .DAF, .IMA

  • Specifications

    • Moving Platform; 35 cm x 35 cm, carries up to 20 kg
    • Overall dimensions; 51 cm x 35 cm x 15 cm high
    • Mass; 3 kg excluding third party phantoms
    • Chest Wall Platform; 13 cm diameter, carries up to 1 kg
    • Power Supply; Input, 100 – 240VAC, 47 – 63 Hz, International power cords available on request. Output, 24VDC, 2.1 A, 50 W. Approvals; CE, UL/CSA 60950-1
  • Minimum Technical Requirements

    • Operating System: Windows 7 SP1, 8.1 or 10
    • Ports: 1 Ethernet
  • 100-1010: QUASAR™ Respiratory Motion Platform

    • 1-Phantom
    • 1-Software License
  • Optional Accessories

    • 500-2004: Heavy-duty Shipping Case 5 kg
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Modus QA has developed an easy-to-use phantom with comprehensive testing capabilities for demanding motion protocols in modern radiation therapy departments. From its manual operation mode to its intuitive hysteresis generator, the Quasar Respiratory Motion Platform was designed with the end user in mind, providing an intuitive motion-management QA tool.

Motion Control Options

Choose easy operation with local manual control at the motor or advanced programmable software-driven control. Apply a lateral hysteresis to your existing phantom, creating a complex motion profile. With playback of motion waveforms, complexity is elevated to test the limits of your motion management systems.

Motion Precision

The QUASAR™ Respiratory Motion Platform exhibits detailed sensitivity when replicating captured or created waveforms. A highly responsive motor repositions the translation stage every 10 ms (100x per second) providing real-life breathing replication. Waveforms from 0-60BPM are replicated with ease, testing a large range of clinical protocols.


Equipped with a large 35 x 35 cm platform surface and accommodating up to 20kg, the QUASAR™ Respiratory Motion Platform enables motion of most industry phantoms, opening the door to a wide variety of motion testing capabilities. Our software determines the safe motion range and speed based on the phantom’s weight.


Included with the QUASAR™ Respiratory Motion Platform is an intuitive programmable respiratory motion QA software. This locally-installed package enables the control of the phantom’s motion and customization of supplied and imported motion waveforms. An incorporated Deep Inspiration Breath Hold Function increases workflow efficiency for users to test DIBH protocols.

Complex Motion Control Options

The QUASAR Respiratory Motion Platform offers full control of your phantom’s motion profile. Our Respiratory Motion QA Software offers multiple operation modes to increase utility. From adjustable sinusoidal waveforms and simple test patterns to accurate playback of complex waveforms, the platform offers the flexibility to choose your motion complexity for your required testing sequence.

Customizable Waveforms

In addition to an extensive library of pre-loaded waveforms, the Respiratory Motion QA Software enables the import of acquired waveforms from a number of respiratory gating and motion tracking systems. The waveforms are completely customizable, improving the user experience when modifying waveform patterns to achieve the desired testing protocol.

Product Information & Accessories


Additional Resources

MEDWIG J., GAEDE S., BATTISTA J.J., YARTSEV S., Effect of later target motion on image registration accuracy in CT-guided helical tomotherapy: A phantom study, Journal of Medical Imaging and Radiation Oncology 54 (2010) 280-286

NAKAMURA M., NARITA Y., SAWADA A., MATSUGI K., NAKATA M., MATSUO Y., MIZOWAKI T., HIRAOKA M., Impact of motion velocity on four-dimensional target volumes: A phantom study, Med. Phys. 36 (5), May 2009, 1610-1617

GALLAGHER, C., YARTSEV, S., VAN DYK, J., Imaging and radiation delivery in helical tomotherapy: Phantom study of a moving target, Poster presented at the 54th Canadian Organization of Medical Physicists (COMP) Annual Meeting, June 25-28, 2008, Quebec, QC, Canada

MEDWIG, J., YARTSEV, S., VAN DYK, J., The Effect of Target Motion on Megavoltage CT Registration, Poster presented at Research Day 2008, Lawson Health Research Institute, March 26, 2008, London, ON, Canada

KEALL P.J., et.al., The management of respiratory motion in radiation oncology report of AAPM Task Group 76, Med. Phys. 33 (2006) 3874 – 3900.

YORKE E., HARISIADIS L., WESSELS B., AGHDAM H., ALTEMUS R., Dosimetric Considerations in Radiation Therapy of Coin Lesions of the Lung, Int. J. Radiation Oncology Biol. Phys., Vol.34, No. 2, pp. 481–487, 1996.

OLIVER M., STARUCH R., GLADWISH A., CRAIG J., CHEN J., WONG E., Monte Carlo dose calculation of segmental IMRT delivery to a moving phantom using dynamic MLC and gating log files, Phys. Med. Biol. 53 (2008) N187–N196.

KORREMAN SS., Motion in radiotherapy: photon therapy, Phys Med Biol. 2012 Nov 20;57(23):R161-R191.