MAUDE Adverse Event Report: ACCURAY INCORPORATED ACCURAY; ROBOCOUCH PATIENT SUPPORT SYSTEM

Lot Number PTRC-003

Device Problems Mechanical Problem (1384); Inaccurate Delivery (2339); Positioning Problem (3009)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 06/11/2015

Event Type  malfunction  

Manufacturer Narrative

Method and materials: our investigation strategy recreated the errant treatment scenario at the mevion factory using a manufacturing equivalent couch, proposed root cause from service notes, and subsequent discussions.We tested two setup and treatment scenarios that encompass the range of possible treatment errors with the compromised couch.We measured the alignment error induced that could have gone undetected.A cube containing a laser trackable fiducial was placed on the couch top, indexed to a reference bar near the center o f the couch top (h1 index mark) and close to the position of the morning qa cube used at the site.Room lasers were previously aligned coincident with couch isocenter to better than 1mm.Conclusions: the magnitude of error observed in the incident report was outside couch sub-millimeter specifications but not above the threshold of a reportable event.The root cause of a motor mount loosened by excessive load followed by a 6-tooth slip of the gear belt is consistent with reported observations.

Event Description

This report identifies a product malfunction in the accuray robocouch patient support system that we believe could result in the serious injury of a patient undergoing radiotherapy treatment.The patient treatment table, including the positioning belt, is part of an accuray premarket notification cleared medical device.No patient death or serious injury has occurred.An investigation conducted by mevion medical systems has determined it is likely the treatment table positioning belt slipped gear positions, resulting in deviation of patient setup and treatment positions from the time of slippage until the discovery of slippage and the halting of treatment.For each of the patients treated, there was a calculated deviation from the planned treatment position of less than 8mm.All patient affected by errant positioning received a single treatment fraction slightly off-target.In each case, the slippage resulted in less than an 8mm deviation from the planned position.We find, however, no basis to conclude that a recurrence of the malfunction could not result in a geometric positioning delta of greater than 10mm from the planned position, resulting in a substantial error in treatment delivery geometry, i.E.The delivered treatment geometry would not precisely meet the application parameters provided by the treatment plan.Mevion medical systems has notified accuray of the product malfunction.

• Brand Name: ACCURAY
• Type of Device: ROBOCOUCH PATIENT SUPPORT SYSTEM
• Manufacturer (Section D): ACCURAY INCORPORATED; 1310 chesapeake terrace; sunnyvale CA 94089
• Manufacturer Contact: thomas faris ; 300 foster st; littleton, MA 01460 ; 9785401500
• MDR Report Key: 5584559
• MDR Text Key: 42954915
• Report Number: 3007087027-2015-00001
• Device Sequence Number: 1
• Product Code: JAI
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K042146
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional,user faci
• Reporter Occupation: Physician
• Remedial Action: Repair
• Type of Report: Initial
• Report Date: 07/21/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Lot Number: PTRC-003
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Initial Date Manufacturer Received: 06/11/2015
• Initial Date FDA Received: 07/24/2015
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 04/30/2015
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Other