>Calypso 4D Localization System Measures Prostate Movement During Radiotherapy

SEATTLE—Calypso Medical Technologies, Inc.'s Calypso 4D Localization System has been granted 510(k) clearance by the FDA to locate the tumor target during treatment setup and monitor organ motion continuously during radiation therapy for prostate cancer patients, without adding ionizing radiation.

The Calypso system works through detection of AC electromagnetic markers called Beacon transponders. The transponders, which are smaller than a grain of rice, are implanted in or near the treatment site. When coupled with the Calypso 4D Localization System, the Beacon transponders send signals that generate objective location instructions to the radiation therapist to register the patient's treatment target to isocenter prior to treatment.

A misalignment of the treatment target can be detected by Calypso Medical's proprietary algorithm that identifies submillimeter shifts of the target from its prescribed location any time throughout the treatment. Through an intuitive graphic user interface, the Calypso system is programmed to exhibit real-time graphs, instantaneously highlighting shifts in position that exceed a predetermined threshold.

The Calypso System was evaluated in clinical studies in patients undergoing prostate radiation therapy between 2003 and 2006. In these studies, investigators documented that clinically relevant prostate motion was present during the delivery of radiation and could be responded to in real-time.