Physica Medica: European Journal of Medical Physics - Volume 32 - Supplement 1 - February 2016

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D.410
ACTIVITY ESTIMATION IN PATIENTS SUBMITTED TO RADIOIODINE
THERAPY FOR HYPERTHYROIDISM
A. Ostinelli M. Duchini V. Conti P. Bonfanti S. Ross M. Cacciatori
a A. O. Sant’Anna, Como, Italy; b Università Insubria, Como, Italy
Introduction: The 131I administered activities for the hyperthyroidism treat-
ments are very high, with significant residual amounts in the following days.
This paper proposes a mathematical algorithm that correlates patient ac-
tivities and external measurements. The results are supported by clinical
and experimental validations.
Materials and Methods: The mathematical model is based on the rela-
tionship between activity, H*(10) rate, gamma constant and source-
detector distance (d), without considering both the distribution of iodine
and uptake through the tissues. An effective distance (deff) was intro-
duced, adding a contribution dx to d, evaluating both the mean depth of
the 131I 3D distribution and the photon-tissues interaction. Two measure-
ments are required at known distances (d1 and d2). Applying the inverse
square law to H*(10) rates and assuming C = (dH*2/dt)0.5/(dH*1/dt)0.5 and
d1 + dx = C(d2 + dx); the residual activity is: F2dH*(10)/dt(d/gamma con-
stant) where F = (d + dx)/d.
Results: This model was validated by clinical trials, comparing the admin-
istered activities with the calculated ones. Comparing these results with
the activities estimated by single measurements, the average deviation from
the expected values decreases from 11% to 0.5%. Additional measure-
ments were performed at the discharge time and four days after, with an
11.3% and 43.0% excreted mean activity. dx is about the radiopharmaceu-
tical depth within the patient, with 82 ± 40, 56 ± 46 and 34 ± 36 mm average
values at 0.5, 4 and 72 hours respectively. This decrease may be due to the
gradual iodine capture by thyroid.
Conclusions: This study proved the validity of the theoretical-experimental
approach, providing a good estimation of the residual activity and an ef-
fective radiation protection tool.
D.411
“OPERRA” PROJECT ON PRIORITIES FOR RESEARCH IN THE FIELD OF
RADIATION PROTECTION: DEVELOPMENT OF A SURVEY
A. Palma * S. Bouffler M. Coeck S. Della Monaca P. Fattibene
S. Grande N. Impens G. Meskens I. Pecchia T. Perko A. Rosi
F. Rollinger S. Salomaa L. Sirkka M.A. Tabocchini C. Turcanu
M. Grigion a Dipartimento di Tecnologie e Salute, Istituto Superiore di Sanità,
Roma, Italy; b Centre for Radiation, Chemical and Environmental Hazards, Public
Health England, Didcot, UK; c SCK CEN Belgian Nuclear Research Centre, Mol,
Belgium; d Institut de Radioprotection e de Surete Nucleaire, Fontenay-aux-Roses,
France; e STUK – Radiation and Nuclear Safety Authority, Helsinki, Finland
Introduction: The EC OPERRA project (Open Project for the European Ra-
diation Research Area) aims to create an innovative mechanism for the
implementation of an instrument of joint programming that can be applied
to all fields of research in radiation protection. In particular, the Task Group
(TG) 4.3 aims to identify national and international stakeholders and to
collect and analyse their opinions on research priorities in radiation pro-
tection. Within this TG, the ISS (TG 4.3.2 leader) has coordinated the creation
of a survey in electronic format.
Materials and Methods: The survey has been developed by the tool ZEF
Evaluation Engine. Data analysis was performed by using ZEF, EXCEL and
SPSS software.
The questionnaire was organised with an initial section containing the syn-
ergistic priorities common to the European platforms MELODI, ALLIANCE,
NERIS and EURADOS. The next four sections contained questions ex-
tracted respectively from each platform Strategic Research Agenda. Finally,
other sections were devoted to issues related to ethical aspects of radia-
tion protection, risk communication and risk perception, and education and
training.
Stakeholders to which the survey should be sent were identified from contact
lists provided by the four platforms and by contacting the presidents of
international scientific associations, the representatives of international
organisations, etc. Each of them has been asked to spread the survey link
to their members and/or advertise on their websites.
Results and Conclusion: In the present work, some key results related to
the synergistic priorities will be shown and discussed. The importance/
feasibility ranking was used for gathering opinion on these topics. Most
responses came from those with interests in low dose risk and dosimetry.
A complete analysis of the results is available on MELODI website
. A selection of such synergistic topics was
recommended as the focus of the second OPERRA call for research proposals.
D.412
QUALITY ASSURANCE AND MANAGEMENT PROGRAM OF INDIVIDUAL
AND ENVIRONMENTAL RADIATION PROTECTION EQUIPMENT IN A ISO
9001: 2008 QUALITY MANAGEMENT SYSTEM
M. Paolucci *, R. Di Lorenzo, A. Didona. USL Umbria 2 – Servizio Di Fisica
Medica, Foligno, Italy
Purpose: USL 2 Umbria was born in 2013 by merging 2 health care insti-
tutions; it’s organized into 6 districts and 8 regional hospitals, where the
Medical Physics Department started a Quality Assurance (QA) and man-
agement system of Personal Protective Equipment (PPE) and mobile radiation
shields, by placing them in the ISO 9001: 2008 Quality Management System.
Materials and Methods: A multidisciplinary workgroup, including the De-
partment of Diagnostic Imaging and Therapeutics and all departments and
structures where radiation sources are used, was created. We started with
census and efficiency check of all the equipment, through a dedicated QA
program on all USL 2 Umbria radiological sites, in collaboration with tech-
nician staff.
Subsequently a protocol for periodic functional and quality tests and a man-
agement procedure were established and a list with minimum necessary
equipment for each radiological site was prescribed.
Results: The Quality Management System was implemented over a period
of about two years, establishing a management and monitoring paper-
work, a program of audits and periodic QA tests on all the equipment, in
order to ensure their correct efficiency, in compliance with regulatory
requirements.
During the QA campaign 483 PPE were tested, 5% of which was replaced
with new equipment as resulted not suitable. We also disposed of 46 PPE
unused because clearly damaged, following an internal procedure accord-
ing to Italian legislation D. Lgs. 152/06. Furthermore a routine sanitization
procedure for each PPE was established for their correct maintenance and
conservation.
Conclusion: The results led to an optimization of the equipment distri-
bution, highlighting the need of continuous checks in order to provide a
proper protection against ionizing radiation during clinical activities for pa-
tients and operators.
D.413
ISO 17025 ACCREDITATION EXPERIENCE OF AN INDIVIDUAL MONITORING
SERVICE
F. Rossi *, L. Fedeli, L. Noferini, M. Fedi, A. Falivene. Fisica Sanitaria AOU
Careggi, Firenze, Italy
Introduction: The European directives, according to ICRP recommenda-
tions, state that for people occupationally exposed to ionizing radiation a
monitoring of absorbed dose is needed, the measuring instrument is called
dosimeter. A service, called IMS (Individual Monitoring Service), is thus
needed, providing not only the instruments but also calibrations, trace-
ability of the name of worker related to dosimeter ID, proper storage of
dose data, and so on. The Directive states that each member State shall
develop approval procedures to state whether an IMS is or not suitable for
its purpose. Italy is actually without any kind of approval procedure. Fur-
thermore, the EC document RP160 states guidelines for IMSs, requiring
compliance to ISO 17025 standard to fulfill adequate quality levels.
Materials and Methods: Our IMS was updated to make it compliant with
ISO 17025 standard. This involved: instrument maintenance, human re-
source proper training, operative procedures, traceability, calibrations,
software, data recording and dose reporting. The updating was very time-
consuming, involving six persons two of them medical physicists.
e121 Abstracts/Physica Medica 32 (2016) e116–e123