Overexposure of two practitioners at the Pitié-Salpêtrière Hospital: ASN classifies the event as level 2 on the INES scale

On 14 November 2017 the Pitié-Salpêtrière Hospital Group (Paris) notified ASN of two significant radiation protection events affecting a resident physician and a head of clinic respectively while performing interventional procedures in neuroradiology. Due to late forwarding of the dosimeters to the laboratory responsible for analysing them, it was discovered in September 2017 that these practitioners had received ionising radiation doses on the hands exceeding the annual regulatory limit for this category of worker (dose to the "extremities" exceeding 500mSv).

• In June 2017 the acting resident physician received a dose to the hands exceeding 500 mSv, and a dose close to this value in September 2017. The cumulative dose received between June 2017 and September 2017 was more than two times the regulatory annual limit.
• Between April 2017 and September 2017 the head of clinic received a cumulative dose to the hands exceeding the annual regulatory limit of 500 mSv.

The hospital group took measures immediately after discovering these two incidents and, on the advice of the occupational physician, stopped the two physicians concerned from practising any further interventional neuroradiology procedures. The analysis of the event showed that these persons received the majority of the dose while performing fluoroscopy-guided lumbar puncture procedures, during which their hands were exposed to the primary X-ray beam emitted by the machine. Corrective actions were put in place to enhance the radiation protection training of the personnel involved in interventional neuroradiological procedures, ensure that dosimeters are analysed in good time, and modify current practices to avoid any exposure of the hands to the primary X-ray beam during these procedures.

ASN conducted an inspection concerning these incidents on 26 March 2018. It confirmed the effectiveness of the corrective actions implemented in consultation with the medical professionals concerned to avoid the recurrence of such an event. The inspection highlighted the need to keep better track of the occupational radiation protection training given to students and new physicians before they perform interventional neuroradiological procedures.

The follow-up letter to this inspection can be consulted on the ASN website.

ASN firmly underlines the obligation for all workers who are exposed to ionising radiation to wear all their dosimeters, particularly in situations of potentially heterogeneous exposure of the hands or the lens of the eye with respect to the whole body, in order to detect any abnormal exposure. In view of the shortcomings observed in many hospitals with regard to the wearing of extremity dosimeters in accordance with the regulatory provisions, ASN does not exclude the possibility that other similar cases of exposure might have occurred but gone undetected.

Considering the exceeding of the annual exposure limit for the hands over a short period of time, ASN rates these events level 2 on the INES scale (international scale of nuclear and radiological events, graded from 0 to 7 in increasing order of severity).