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GPS For the Body: The Calypso® 4D Localization System™

How Calypso Works

The Calypso technology consists of three components that work together to help your radiation oncology team manage organ motion during the delivery of external beam radiation therapy.


Beacon® transponders

Beacon® transponders

Each transponder is the size of a grain of rice and designed for permanent implantation within the prostate prior to external beam radiation therapy.  The transponders are comprised of wireless electromagnetic circuits that are designed to interact with the other two components of the Calypso System.

The transponders’ role within the prostate is to locate the prostate tumor’s position, help ensure accurate placement and setup prior to treatment, and, provide continuous guidance for precise monitoring of the tumor location in real-time throughout the treatment session.


The Calypso® 4D Localization System™

Activate transponders

Activate transponders

Transponders send signals back

Transponders send signals back

The prostate is monitored during treatment

The prostate is monitored during treatment

The implanted electromagnetic transponders are excited and detected by the Calypso System.  The Calypso System is physically located in the patient treatment room.  The Calypso System and the 4D Tracking Station™ work in tandem with the patient’s implanted transponders allowing the therapist to precisely position the patient prior to radiation therapy treatment and then continuously and precisely monitor the tumor’s position relative to the  radiation beam pathway during each treatment session — GPS for the Body®.

The Calypso® 4D Localization System

4D Tracking Station™

The 4D Tracking Station™ is used by the therapist to monitor tumor position and motion during treatment delivery.  This allows the clinician to make “just-in-time” patient positioning adjustments, as necessary, to optimize external beam treatment delivery — GPS for the Body®.

4D Tracking Station

This page was last updated on: August 13, 2009.


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