Medical device manufacturer, Varian Medical Systems has issued a medical device safety alert concerning 4D Integrated Treatment Console (4DITC) v10.2.3 and Bar-Code Conical Collimator (BCCV) v1.0.

The Plan Label is not updated correctly in BCCV display if multiple plans are open in 4DITC simultaneously. The BCCV display always displays the Plan Label of the first plan. This situation arises only when multiple conical collimator plans are scheduled to be treated in single session.

Based on the BCCV display, it could be possible that the user may choose a wrong plan from a positioning system that is not interfaced with the 4DITC. If the error of selecting the unintended isocenter in the positioning system went unnoticed, treatment to the incorrect isocenter, with the MU's and conical collimator size intended for another isocenter could cause a severe under dose or over dose. Serious injury or death could occur when a hypo-fractionated radiosurgery field is to be delivered. However, the manufacturer has not received any reports of misadministration.

The manufacturer advised the affected users to take the following recommended actions:

• Do not use BCCV as a primary reference for identifying the correct plan to be treated. The user should always refer to the 4DITC for identification of the plan and field that has been moded up for treatment. Care must be taken at all times in selection of the isocenter in the positioning system. The printed information sheet from the treatment planning system should match the patient name and plan name on the 4DITC before selection of the isocenter in the positioning system. It is imperative that a secondary check of the patient ID, plan name and isocenter selection be made before treatment commences.
• Caution should be used when selecting an isocenter in a positioning system that is not interfaced to the 4DITC.
• Any discrepancies in planned versus actual parameters should be brought to the attention of the medical physicist for investigation before treatment begins.
• One workaround is to schedule one plan per session.

The solution of the problem consists of a software upgrade to the BCCV from v1.0 to v2.0.

According to the local supplier, the affected products were distributed in Hong Kong.

If you are in possession of the affected product, please contact your supplier for necessary actions.

Posted on 22 November 2012