Replies to post #50313 on Biotech Values

[Tina]

drb, I am a hospital analyst and have done research primarily utilizing documented medical data pertaining to the effectiveness of this machine.

Yes, I read what you've posted already. However, it is littered with the verbiage "opinion" which IMO is just that.

This is a LONG term hold for me not just some pump and dump. I give more credibility to seasoned researchers/specialists in this field such as well known cancer centers like Stanford Medical Center and several other documented findings over some kid/geek sitting behind a desk giving their financial "opinions" which have been known to be wrong in the past.

[Tina]

"Studies" and not "opinions"

Neurosurgery. 2007 Feb;60(2 Suppl 1):ONS147-56; discussion ONS156.

A study of the accuracy of cyberknife spinal radiosurgery using skeletal structure tracking.Ho AK, Fu D, Cotrutz C, Hancock SL, Chang SD, Gibbs IC, Maurer CR, Adler JR.
Department of Radiation Oncology, Stanford University Medical Center, Stanford, California 94305-5304, USA. [e-mail]

OBJECTIVE: New technology has enabled the increasing use of radiosurgery to ablate spinal lesions. The first generation of the CyberKnife (Accuray, Inc., Sunnyvale, CA) image-guided radiosurgery system required implanted radiopaque markers (fiducials) to localize spinal targets. A recently developed and now commercially available spine tracking technology called Xsight (Accuray, Inc.) tracks skeletal structures and eliminates the need for implanted fiducials. The Xsight system localizes spinal targets by direct reference to the adjacent vertebral elements. This study sought to measure the accuracy of Xsight spine tracking and provide a qualitative assessment of overall system performance. METHODS: Total system error, which is defined as the distance between the centroids of the planned and delivered dose distributions and represents all possible treatment planning and delivery errors, was measured using a realistic, anthropomorphic head-and-neck phantom. The Xsight tracking system error component of total system error was also computed by retrospectively analyzing image data obtained from eleven patients with a total of 44 implanted fiducials who underwent CyberKnife spinal radiosurgery. RESULTS: The total system error of the Xsight targeting technology was measured to be 0.61 mm. The tracking system error component was found to be 0.49 mm. CONCLUSION: The Xsight spine tracking system is practically important because it is accurate and eliminates the use of implanted fiducials. Experience has shown this technology to be robust under a wide range of clinical circumstances.