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                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
              OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
                           WASHINGTON, D.C.  20555

                               January 31, 1992


NRC INFORMATION NOTICE 92-10:  BRACHYTHERAPY INCIDENTS INVOLVING
                               IRIDIUM-192 WIRE USED IN ENDOBRONCHIAL
                               TREATMENTS


Addressees 

All Nuclear Regulatory Commission (NRC) licensees authorized to use 
iridium-192 for brachytherapy; manufacturers and distributors of iridium-192 
wire for use in brachytherapy.

Purpose

This information notice describes two events in which iridium-192 wire 
attached to an unirradiated, flexible guide wire became detached from the 
guide wire.  The use of iridium-192 wire for intracavity brachytherapy 
treatment is not authorized under 10 CFR 35.400, and may only be authorized 
by a customized license review and amendment.  In one event, a portion of 
the iridium-192 wire remained in the patient's thorax.  It is expected that 
licensees will review this information for applicability to their programs, 
distribute it to members of the Radiation Safety Committee and to 
responsible staff and hospital management, and consider actions, if 
appropriate, to prevent similar incidents from occurring at their 
facilities.  Suggestions contained in this information notice do not 
constitute new NRC requirements, and no written response to the notice is 
required.

Description of Circumstances 

Two brachytherapy incidents have been reported that involved endobronchial 
treatment of patients using iridium-192 wire.  The brachytherapy device 
consisted of activated iridium-192 wire of specified activity content 
attached to a nonradioactive guide wire.

On January 6, 1989, an iridium-192 wire used for an endobronchial 
brachytherapy treatment of a patient was not retrievable and had to be 
removed surgically.  When the iridium-192 wire was received by the hospital 
staff, it was not encased in the closed-end nylon tube, described in the 
manufacturer's instructions.  The unencased wire, attached to a flexible 
nonradioactive guide wire, was placed in an opened-end catheter and the 
catheter was introduced into the patient's thorax through a bronchoscope.  
The calibrated activity of the iridium-192 wire was 86.9 millicuries, and 
the length was 7 centimeters.


9201280345 
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                                                      IN 92-10
                                                      January 31, 1992
                                                      Page 2 of 3


While inserting the wire into the catheter, personnel noticed that the wire 
could not travel down as far as they had planned.  The wire was pulled back 
to determine the cause of the obstruction.  Approximately 5 cubic 
centimeters of saline solution were introduced into the catheter to 
facilitate removal of any possible obstruction and reinsertion of the wire.  
However, before a second attempt was made to reinsert the wire, personnel 
noticed that the wire was markedly shorter than its original length.  At 
that point, personnel presumed that the radioactive part of the wire was 
withdrawn but broken off in the catheter.  After withdrawing the catheter, 
personnel found that the missing radioactive part had slipped through the 
catheter and remained in the patient.  The bronchoscope was withdrawn.  
Surveys conducted on the patient's chest revealed an elevated exposure rate 
confirming that a portion of the iridium-192 wire remained in the patient's 
thorax.

A bronchoscope was re-introduced into the patient, and several unsuccessful 
attempts were made to locate and remove the wire.  A thoracotomy was 
performed on the patient and the wire was removed with no further 
complications.  In this event, the iridium-192 was neither encased in a 
nylon tube when it arrived at the hospital, nor was it placed in a 
closed-end tube.  

On July 7, 1989, at a different facility, an iridium-192 wire for an 
endobronchial treatment was received unencased and then used in an open-end 
catheter.  The wire had a calibrated activity of 157.7 millicuries and a 
length of 4 centimeters.

Upon completion of the treatment, the guide wire was withdrawn from the 
patient and placed in the shielded transport container.  The patient was 
immediately surveyed, in accordance with procedures, with a Geiger counter 
that showed readings in excess of 300 mR/hr.  Assuming that the iridium-192 
wire had remained lodged in the patient, the personnel involved in this 
procedure immediately withdrew the open-end catheter used to contain the 
wire.  A subsequent survey of the patient showed background readings.  A 
wipe test of the room and the guide wire that was attached to the 
iridium-192 wire showed no removable contamination.

An autoradiograph of the catheter showed that it contained the intact 
4-centimeter iridium-192 wire.  Personnel concluded that the radioactive 
wire became detached from the guide wire when it was being withdrawn from 
the patient and remained inside the catheter.

Discussion

Although neither of these incidents was a reportable misadministration, the 
first incident resulted in an unanticipated surgery and constituted a health 
risk to the patient. In each of the two events, all or part of an 
iridium-192 source attached to a nonradioactive guide wire became detached 
from the guide 
.

                                                      IN 92-10
                                                      January 31, 1992
                                                      Page 3 of 3


wire.  The involved licensees adopted the following procedural measures to 
prevent this type of event from reoccurring: 

      The iridium-192 wire will be inspected and tested in the hot 
      laboratory prior to implantation.  
      
      The iridium-192 wire for brachytherapy endobronchial treatments will 
      be inserted using fluoroscopy.

      The licensees will contact the manufacturer about the possibility of 
      obtaining an iridium-192 wire encased in a closed-end tube.

      If resistance is encountered while the iridium-192 wire is being 
      withdrawn, no force will be used to remove it, because such force may 
      break or dislodge the radioactive wire.  Instead, the catheter 
      containing the wire will be removed.

This information notice requires no specific action or written response.  If
you have any questions about the information in this notice, please contact 
the technical contact listed below or the appropriate regional office. 




                                    Richard E. Cunningham, Director
                                    Division of Industrial and 
                                      Medical Nuclear Safety
                                    Office of Nuclear Material Safety
                                      and Safeguards


Technical contact:  Harriet Karagiannis, AEOD
                    (301) 492-4258

Attachments:  
1.  List of Recently Issued NMSS Information Notices
2.  List of Recently Issued NRC Information Notices

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