Varian TrueBeam With Vision RT’s AlignRT®/OSMS – Unexpected Overwrite of Plan Couch Parameter

Varian Medical Systems issued an Urgent Field Safety Notice (ref. CP-23897) on June 24, 2016. Varian Medical Systems has been notified by Vision RT that unintended changes can be made to planned couch parameters, specifically the couch rotation parameter, during patient set-up. This can occur when a user sets a different couch rotation from the plan couch rotation while performing patient alignment with Vision RT’s AlignRT® device or Optical Service Monitoring System (OSMS) prior to treatment with the TrueBeam® Radiotherapy Delivery System [TrueBeam] version 2.0/2.5. Neither Vision RT nor Varian has received any report of patient harm due to this issue. The notice describes the recommended user actions: (1) DO NOT USE the “Move Couch” function if the couch rotation value set in the AlignRT® device DOES NOT match the planned couch rotation for the treatment field and (2) Varian recommends that the user ALWAYS confirm that the patient is correctly aligned prior to commencing treatment. The notice describes further details.

Varian Eclipse – Erroneous Conventional Arc Field Dose Calculation With PBC Algorithm

Varian Medical Systems issed an Urgent Field Safety Notice (ref. CP-23187) on January 11, 2016. Varian Medical Systems has received a report of an anomaly involving Eclipse™ Treatment Planning System Pencil Beam Convolution (PBC) 11.0.31 to compute a conventional arc dose distribution. When using PBC 11.0.31 to calculate the dose for a conventional arc field with more than 100 segments with Eclipse versions 11, 13, 13.5 or 13.6, the displayed dose does not correspond to the calculated Monitor Units (MU). Varian has not received any report of misadministration due to this issue. Eclipse version 10 and lower using PBC are not affected. Eclipse versions 11, 13, 13.5 or 13.6 using PBC 10.0.28 are not affected. RapidArc® plans are not affected, because PBC cannot be used with RapidArc. Arc plans for TrueBeam® Radiotherapy Systems are not affected. Varian recommends the following: (1) DO NOT USE Eclipse version 11, 13, 13.5, or 13.6 with PBC 11.0.31 algorithm for conventional arc field dose calculation and (2) use the Eclipse Anisotropic Analytical Algorithm (AAA) or Acuros® XB advanced dose calculation algorithm for conventional arc field dose calculation. Users can verify whether a plan generated by Eclipse version 11, 13, 13.5 or 13.6 using PBC 11.0.31 exceeds the 100 segment limit for a given field by reviewing the calculation log files. The affected fields should be evaluated by re-calculating the plan with either: AAA, Acuros® XB or PBC 10.0.28 dose calculation algorithms. For conformal arc plans, fields can also be evaluated in the properties of the dynamic MLC. More details are provided in the notice.

Elekta – Incorrect Field Size When DICOM Exporting Monaco 3D Plan

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 382-01-MON-004) May 13, 2016. The affected product is Monaco version 5.10.00 and higher. When DICOM exporting a 3D Monaco plan and the “Composite Field Sequencing” (CFS) checkbox is selected, the Y jaws will snap to the port shape when they should remain where they were defined. This occurs when the port shape used to define or edit the MLC positions extends beyond or inside the actual jaw positions. The defect is triggered when using a workflow for Forward Planning IMRT that involves creating multiple beams for the same gantry angle with a single MLC shape defined for each beam. These beams are then exported using CFS to combine the individual 3D beams into a single IMRT beam sequence. The planned and approved dose distribution will not agree with the dose delivered. IMPAC states this deviation is considered a geometric miss and the patient can be overdosed or underdosed depending on whether the MLC shape is drawn outside or inside of the collimator jaws. There is a remote probability that serious injury could occur. The stated IMPAC workaround is to avoid using the CFS option for any 3D delivery mode plan including Forward IMRT based plans. IMPAC says this problem will be resolved in patches to the following Monaco Releases: 5.11 and 5.20.

Elekta – Unintended Change to Plan-of-the-Day Selection

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 371-01-MSQ-006) in 2016. The affected product is MOSAIQ version 2.62 and higher with the IQ Scripts license enabled. Clicking on the Treat button in the Treatment Chart window will trigger the Plan-of-the-Day IQ script to run. The Plan-of-the-Day window will open and the treatment plan can be selected by clicking on the radio button. It is possible that the selected Plan-of-the-Day could be accidently changed by scrolling the mouse wheel up and down and inadvertently selecting another plan. Though the wrong Plan-of-the-Day selected for one fraction would likely not result in Critical harm, if the wrong plan were selected multiple times it could result in serious injury. The notice says there is no workaround, but the problem can be avoided by careful use of a mouse with a wheel (or using a mouse without a scroll wheel) and verifying that the correct plan is chosen before selecting OK on the Plan-of-the-Day form. IMPAC stated the issue is corrected in the general release of MOSAIQ 2.64. A patch is also being developed for MOSAIQ release 2.62. IMPAC indicated they will notify users when this release is available.

Elekta – Incorrect Field Size for Stereotactic Cones

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 371-01-MSQ-003) in 2015. The affected product is MOSAIQ. Sites affected are those meeting ALL three of the following criteria: (1) running MOSAIQ Release 2.41 and higher, (2) with at least one linac equipped with an Agility 160 MLC head (Versa HD, Infinity, Axesse (EOS) or Synergy), and (3) users who are treating with Stereotactic Cones. A problem exists in MOSAIQ resulting in the incorrect field size being sent to the treatment machine for stereotactic plans. A description of the process that initiates the problem is described in the notice. IMPAC states the patient could be lethally overdosed, although the probability is remote. For stereotactic treatments, a larger than intended area would be treated and the overdose could be large. Per IMPAC, the problem can be avoided by clicking Cancel on the Create Simple MLC window, editing the field size values in the Create Simple MLC window to return to the correct MLC shape for the planned cone before saving or by not using the Simple MLC view. IMPAC states this problem will be resolved in a future release of the following MOSAIQ versions: MOSAIQ 2.41, MOSAIQ 2.50, MOSAIQ 2.60, and MOSAIQ 2.62. The notice states Elekta will contact users when the relevant MOSAIQ build is released containing the fix. Elekta states this is mandatory upgrade to the appropriate version.

Elekta – Dose and MU Incorrect (2 Scenarios)

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 382-01-MON-002) in 2015. The affected product is Monaco 5/10.00. Scenario 1 – Dose and MU Incorrect When CT Images Viewed From the Head: In Radiation Therapy, CT images are typically presented as if the viewer is standing at the foot of the couch and looking toward the patient’s head (if the patient is supine, the patient’s left is on the right side of the screen). However, for Neurosurgery, images are often created as if being viewed from the top of the couch looking toward the patient’s feet (supine patient’s left will be presented on the left of the screen). When CT images are created this latter way and imported in Monaco, the image is displayed correctly but the electron densities are incorrectly flipped in both the right-left and superior-inferior directions. The bulletin states dose distribution and monitor units will be incorrect. There is a remote probability that serious injury could occur. Scenario 2 – Dose and MU Incorrect When Using Multiple Prescriptions With Forced Densities: When using Multiple Prescriptions and the first prescription has forced densities, these forced densities are not being maintained with the second prescription. The notice states dose distribution and monitor units will be incorrect as the initial prescription will use forced densities and the second prescription will use CT densities. Over the range of electron densities commonly found in patients, IMPAC states there is a reasonable probability that non-serious injury would occur. For both scenarios, IMPAC states the problems will be resolved in Monaco Patch Release 5.10.01.

Elekta – Unintended Update of Dose and MU, and Incorrect Assignment of Bolus

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 382-01-MON-003) in 2015. For the Unintended Update of Dose and MU, the affected product is Monaco 5.10.01. In version 5.10.01, the Isodose Control 100% isodose value (second in the list) was linked to the Dose Normalization value so users would always have a known normalization value linked to 100% when in relative mode. This however limits the user to only one defined value available above 100%. When the 100% isodose value is edited on the isodose control, the Dose Normalization is automatically updated. If the user does not notice this update and then rescales to a relative isoline and does not read the Dose Normalization value displayed on the rescale bar, the rescale could be other than intended. Applying an isodose template could automatically update the Dose Normalization value. When rescaling at this point, rescales will be relative to the new dose normalization value and again the user could fail to read the dose normalization value displayed in the rescale bar and Dose Normalization panel. The notice states dose distribution and monitor units may not reflect the intent when the dose normalization value is updated. There is a remote probability that non-serious injury could occur. The workaround is to only assign one value greater than 100% as the system is defaulted so the 100% isodose line and dose normalization values are not affected. When rescaling, the dose normalization value is displayed next to the rescale value being entered by the user. IMPAC states this problem will be resolved in Monaco Patch Release 5.10.02. For the Incorrect Assignment of Bolus, the affected product is Monaco 5.10.00. In version 5.10.00, when the user optimizes, then changes the bolus assignment of the beams, and then selects “Calculate” (not “Optimize” again), the bolus assignment to beams can get scrambled. Beams that should have bolus assigned do not and beams that do not have bolus assigned calculate with bolus. The dose distribution and Monitor Units are incorrect for the bolus assignment of the beams. Also, the reports show beam information that is incorrect for the bolus assignment. The DRP and Prescription page are not updated correctly. Skin doses could either be higher of lower than intended and this increase or decrease in dose could exceed 5%. IMPAC states the dose distribution and monitor units will be incorrect for the indicated bolus assignment. There is a remote probability that serious injury could occur. The notice says there is no workaround using the described workflow. However, the problem can be avoided by changing any bolus assignment before optimization. IMPAC states this problem will be resolved in Monaco Patch Release 5.10.02.

Elekta – Incorrect Treatment Delivery Using Third Party Fixed Wedges

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 382-01-XiO-001) in 2015. The affected product is XiO. The sites affected are those: (1) running XiO Release 4.51 and higher, and (2) using Elekta linacs, and (3) using third party fixed wedges in combination with MLCs. When fixed wedges are defined in Source File Maintenance, the user defines a maximum field size allowed for each wedge. This maximum field size is being ignored by the software when both fixed wedges and MLCs are present in a beam. The result is incorrect calculation and delivery of dose outside the physical extent of the wedge. The dose distribution calculated by XiO will not match the dose delivered to the patient in regions beyond the physical dimension of the wedge. Varian and Siemens linacs will prevent delivery. Elekta linacs with motorized wedges will prevent delivery. Elekta linacs with third party fixed wedges will not prevent delivery. XiO will calculate wedged dose in the region outside of the physical wedge and the linac will deliver open dose. The patient will receive dose that is different from the planned dose and that dose difference can exceed 5%. Elekta states there is a remote probability of serious injury resulting from this issue. The problem will be resolved in a patch to XiO Release 5.10.

Elekta – Incorrect Decimal Symbol or Unintended Modification of Numeric Data

IMPAC Medical Systems issued an Urgent Field Safety Notice (ref. no. FCO 371-01-MSQ-001) in 2014. The affected product is MOSAIQ. The sites potentially affected are those: (1) running MOSAIQ Releases 2.50.04E1SP6 and higher, and (2) located in one of the specified countries (see the list of countries shown on the notice – NOTE: the United States is NOT shown on the list), and (3) using Runtime Language code that is associated with a decimal symbol format that is different from that defined in the Windows Control Panel settings for Region and Language. IMPAC says to contact your local Elekta office to check your system files to determine whether your site is affected. Depending on MOSAIQ and Windows Operating System settings, a problem can exist in MOSAIQ resulting in the display of an incorrect decimal symbol and/or unintended modification of numeric data by factors of 10 (multiplication by 10, 100, 1000, etc.). Inconsistencies may also occur in date and time formats. See the notice for specifics of the problem. The problem can be avoided by not using the optional “Runtime Language” override. If dose or treatment time is affected, the patient could be greatly overdosed and the consequence could be Lethal. If a geometric parameter is affected (field size, depth, angle) there could be a geometric miss and a target could be underdosed and normal structures overdosed. This could result in serious adverse health consequences. IMPAC states the resolution to this issue is now available for MOSAIQ releases 2.50 and 2.60. IMPAC recommends that the user upgrade to the appropriate service pack for the MOSAIQ version that the site is currently using clinically.

Varian 4DITC – Unexpected Auxiliary Device Authorization

Varian Medical Systems issued an Urgent Field Safety Notice (ref. CP-16016) on August 19, 2014. The affected product is the 4DITC Integated Treatment Console (4DITC version 10 and 11). Varian recently received two reports of treatment workflows for a C-Series High Energy (HE) linear accelerator with two auxiliary devices, specifically Brainlab’s ExacTrac® patient positioning device and Varian’s Barcode Conical Collimator Verification (BCCV) device. In both these cases, the user sent successive ready [authorization] signals from the ExacTrac® to the 4D Integrated Treatment Console [4DITC]. The signals are sent through the Auxiliary Device Interface [ADI]. These successive signals unexpectedly cleared both the ExacTrac® interlock and the BCCV interlock on the linac. It was possible to initiate treatment delivery with the linac even though BCCV still showed “pending” status. Varian has not received any report of patient injury due to these workflows. The TrueBeam™ is not affected. Varian’s recommended user action and associated details are discussed in the notice. Varian has developed a fix for this issue and will contact all users.

Varian C-Series – Unexpected 6MV Beam Output Variations

Varian Medical Systems issued an Urgent Field Safety Notice (ref. CP-12459) on June 17, 2014. The affected product is the C-Series High Energy Linear Accelerator (Novalis Tx, Trilogy, Trilogy Tx, Clinac iX, Clinac CX, Clinac 2100 C/D, Clinac 2300C/D, Clinac DX, Clinac 21 EX, Clinac 23 EX). Varian has seen a trend in reports of unexpected decrease in beam output in C-Series High Energy [HE] Linear Accelerators for 6MV photon treatment mode. To-date Varian has not received any report of misadministration or injury due to this 6MV target degradation or failure. TrueBeam™ and Varian Low Energy Linear Accelerators [e.g., 600C series, Unique] are NOT AFFECTED. Varian has determined the cause of the unexpected variations in beam output to be degradation of the 6MV target. This failure mode in the target only affects the 6 MV photon treatment modes (6SRS, 6FFF and 6X). No other energies are affected. Varian strongly recommends that all sites implement daily output constancy checks of photon beams as recommended by the AAPM. Specifically those provided by: (1) AAPM, Task Group 142 Report: Quality Assurance of Medical Accelerators, Medical Physics publication 36 (9), September 2009, and (2) AAPM Report No. 46, Comprehensive QA for Radiation Oncology, Report of Task Group No. 40 Radiation Therapy Committee, April 1994. More details are provided in the notice.

Varian OBI – Exact Arm Elbow Motor Shaft

Varian Medical Systems issued an Urgent Field Safety Notice (ref. CP-14167) on March 20, 2014. The affected product is Type 01 Elbow Motors. Varian has received three reports that the shaft of the Type 01 elbow motor for Exact arms used in the On-Board Imager® [OBI] device have failed due to belt over-tensioning. This over tensioning would have taken place during servicing. This failure would allow the Exact arm to swing freely with gravity. This notice provides a description of the issue, the actions you can take to avoid or mitigate the issue, and steps Varian Medical Systems is taking to address the issue. No injuries have been reported to-date. Only Type 01 elbow motors are subject to these potential failures. Later Type 02 elbow motors are not affected. TrueBeam is not affected. Only users whose accelerators were shipped with OBI Type 01 Elbow motors will receive this Varian notice. The notice stated a Varian Medical Systems Customer Support Service representative will arrange a site visit to check the belt tension of the Type 01 elbow motors of all OBI and MV Exact arms. If over-tensioned belts are detected, the elbow motor will be replaced with a Type 02 elbow motor.

Varian VariSeed – Correct Units of Activity

Varian Medical Systems issued an Urgent Field Safety Notice on January 19, 2012. The affected product is all versions of VariSeed. Varian advises VariSeed users to enter the sourse activity using correct units of activity. Specifically, some VariSeed users have inadvertently entered the source activity in units of air kerma (U) when the actual source activity was specified in millicuries (mCi). The notice describes the issue, the actions you can take to avoid or mitigate the issue, and steps Varian is taking to address the issue.

TECHNICAL ADVISORY

Varian ARIA – Incorrect Storage and Display of OAR Dose-Volume-Constraints

Varian Medical Systems issued a Technical Advisory (ref. CP-26231) on August 15, 2016. An anomaly has been identified in Prescribe Treatment version 13.6 with the storage and subsequent display of organ at risk (OAR) dose-volume constraint values. OAR constraint values are displayed incorrectly in 13.6 Prescribe Treatment workspace if the prescription was created in version 11.0, 13.0 or 13.5. The storage location for dose and volume constraints is swapped in version 13.6. As a result of this anomaly, the display of the OAR dose-volume constraints will differ depending on the version in which they were created and the workspace version in which they are displayed. In the notification, Varian strongly recommends that users review the OAR constraint values and correlate with clinical nomenclature before proceeding with creating a treatment plan.

Varian CBCT – Acquisition Stalls, Repeat Scan Required

Varian Medical Systems issued a Technical Advisory (ref. CP-22609) on February 8, 2016. Varian has received several reports of the On-Board Imager® Cone Beam CT [CBCT] acquisition stalling and preventing reconstruction of the image. A repeat scan will be required. There are two possible symptoms: (1) the CBCT application stops updating the display during acquisition and/or (2) an exception occurs during the acquisition. Although CBCT projections will have been acquired, it will not be possible to generate the reconstructed CBCT and the scan must be repeated. There have been no misadministration or injuries reported due to this issue. The notice describes the issue and the actions you can take to correct the issue.

Varian Portal Dosimetry – Limited Eclipse Ver. 11 Functionality

Varian Medical Systems issued a Technical Advisory (ref. CP-21657) on November 16, 2015.  Per Varian, the 43×43 Large Field Imager is standard on the Edge™Radiosurgery System, and the TrueBeam™ or VitalBeam™ Radiotherapy Systems. But Eclipse™ Treatment Planning System version 11 provides limited Portal Dosimetry verification functionality for the 43×43 Large Field Imager. Eclipse® version 11 can be ONLY used for Portal Dose Image Prediction with flattened photon beams. Eclipse® version 11 Portal Dose Calculation (PDC) functionality is not available for Flattening Filter Free (FFF) beams. The notification provides instructions to augment current product labeling to enable Portal Dosimetry verification with Eclipse version 11 using the 43×43 Large Field Imager. Varian states Portal Dose verification functionality is available for FFF and flattened beams for the 43×43 imager with Eclipse™ version 13.

Varian TrueBeam – Potential Increase in Ambient Dose After Extended High Energy Use

Varian Medical Systems issued a Technical Advisory (ref. CP-20951) on July 17, 2015. Varian recently received a report of an increase in ambient dose measurement due to target activation after extended operation in high energy mode. Only TrueBeam® RadioTherapy Delivery Systems versions 1.6, 2.0 and 2.5 with 18MV [23MV-BJR17] and 20MV [25 MV-BJR17] energies are affected. Measurements of ambient exposure simulating treatment activites consisting of repeated 4 Gy irradiations separated by 10 minutes over a 4 hour period exceeded Varian’s specification. The ambient dose measurements taken at 1 meter below the collimator face were less than 100 µSv/h. This issue does not impact patient safety or treatment delivery. Varian has not received a report of any person receiving excess radiation exposure due to this issue. Varian’s recommended user action is the following: (1) close the jaws after high energy photon treatments are complete or (2) use the alternative measures listed in the notification.

PRODUCT ADVISORY

Varian TrueBeam – Third Party Device Interfaces

Varian Medical Systems issued a Product Advisory on June 30, 2016. Varian has become aware of third party devices being used with TrueBeam® Radiotherapy Delivery Systems version 1.5 and 1.6 which have not been validated by Varian. This product advisory is being issue to remind users that there is only one third party device which has been validated with TrueBeam® version 1.5 or 1.6 third party interface. Varian states the only third party device that has been validated for TrueBeam® version 1.5 or 1.6 systems is Brainlab ExacTrac®, versions 6.0, 6.1 and 6.2. Use of any third party device other than Brainlab ExacTrac® on a TrueBeam® version 1.5 or 1.6 system could potentially introduce a hazardous situation to the site. As a result, patient safety could potentially be compromised. This notice describes the recommended user action.

Varian Products – Microsoft Windows® 10 Upgrade

Varian Medical Systems issued a Product Advisory (ref. CP-21344) on July 20, 2015. Microsoft recently announced they would provide free Windows 10 upgrades to eligible customers beginning 29 July 2015. Varian states that no Varian products have been validated for operation with Windows 10. If any user of Varian products accepts and installs the Windows 10 upgrade, patient safety could be compromised. Varian has not had the opportunity to conduct testing or validation to confirm Varian products can operate safely and effectively while running on Windows10. Varian’s recommended user action is the following: (1) DO NOT upgrade to Windows 10 and (2) stop use and contact a Varian representative immediately if you have already upgraded to Windows 10®.