Calypso's Dynamic Edge Gating Technology reduces side effects of
radiation therapy
9 Nov 2010
Calypso Medical Technologies, Inc has introduced Dynamic Edge
Gating Technology, recently cleared by the US FDA, at the 52nd Annual
Meeting of the American Society for Radiation Oncology (ASTRO).
Dynamic Edge Gating Technology is used in the company's Calypso
system to allow radiation therapists to set motion thresholds which
disable radiation delivery if the targeted tissue moves outside the
preset threshold.
The Calypso System, which provides target position information in
the form of objective data, previously relied upon the therapist to
manually intervene and halt radiation delivery when healthy tissue
was in danger of receiving unintended radiation.
Dynamic Edge Gating Technology automates this function and provides
an immediate response so the radiation beam is automatically
disabled or re-enabled in response to organ motion.
As a result, this technology may enable a further decrease in the
side effects associated with prostate radiotherapy, such as bowel
and bladder incontinence and sexual dysfunction, because healthy
tissue is protected from receiving radiation intended for the
tumour.
A May 2010 study in Urology, titled Assessing the Impact
of Margin Reduction (AIM), demonstrated that patients whose
radiotherapy delivery was guided by the Calypso System experienced a
significant decrease in the side effects associated with prostate
radiation treatment.
Using Calypso’s real-time tracking, physicians were able to
decrease the treatment margin of irradiated healthy tissue
surrounding the tumour to just a few millimetres. Because less
healthy tissue received radiation, patients reported fewer side
effects.
Combining the decreased treatment margins of the AIM study with
the automated radiation beam response of Dynamic Edge Gating has the
potential to further reduce prostate radiation therapy side effects
since the radiation beam will now be enabled or disabled
automatically, based on objective motion threshold data, as opposed
to manual intervention by the therapist.
“A hallmark of the Calypso System is its ability to accurately
target the cancer and protect adjacent healthy tissue by displaying,
in real-time for each moment of every patient treatment session, the
type and degree of organ motion present,” said Lorraine Marshall
Wright, chief marketing officer and vice president of Calypso
Medical.
“The automatic response to organ motion of Dynamic Edge Gating
should give treating physicians the confidence to decrease treatment
margins, as shown in the AIM study, and ensure their patients
experience the curative benefits of radiation therapy and fewer of
the potential side effects.”
The Calypso System, with its GPS-for-the-Body technology,
utilizes miniature implanted Beacon transponders to provide precise,
continuous information on the location of the tumour during external
beam radiation therapy. Any movement by the patient, including
internal movement of the tumour, may cause the radiation to miss its
intended target and hit adjacent healthy tissue.
In contrast to other tumour targeting solutions, the Calypso
System provides continuous tumour position information, objectively
and without ionizing radiation, thereby enabling an increase in the
radiation delivered to the tumour while reducing radiation
misapplied to normal tissue.