XiO Radiation Treatment Planning System, Versions 4.30.00-4.64.00. Used to create treatment plans for any cancer patient for whom external beam radiation therapy or brachytherapy has been prescribed. The system will calculate and display, both on-screen and in hard-copy, either two- or three-dimensional radiation dose distributions within a patient for a given treatment plan set-up.

XiO will underestimate the dose delivered when the closed leaf gap is set to 0mm on XiO and a value other than 0mm is set on the accelerator.

Computerized Medical Systems, Inc. sent an Important Safety Notice the week of April 30, 2012, by regional support managers via e-mail, fax, or regular mail to all affected customers. The letter identified the product, the problem, and the action to be taken by the customer. North American customers were instructed to go to www.elekta.com, select the SupportPlus Login at the top of the page, enter their portal, select Downloads/Updates to download the latest patches. For Customers outside North America, go to www.elekta.com, select the SOFTWARE button on the left, Treatment Planning Software, then Contact TPS Support tab, Download TPS Software Patches. ............................................................. Customers were also instructed to distribute this notice to any and all users of CMS software at their organization who are potentially affected by this issue. For questions regarding this recall call 408-380-8023.