ORAMED: Optimization of Radiation Protection of Medical Staff

Dr. Ir. Filip Vanhavere

Belgian Nuclear Research Centre (SCK-CEN), Mol, Belgium

1°. SCK•CEN: Belgian Nuclear Research Centre, BelgiumF. Vanhavere, L. Struelens, S. Krim

2°. GAEC: Greek Atomic Energy Commission, Greece E. Carinou, C. Koukorava

3°. ENEA: Radiation Protection Institute, ItalyG. Gualdrini, P. Ferrari, F. Mariotti

4°. IRSN: Institut de Radioprotection et de Sûreté Nucléaire, FranceI. Clairand, L. Donadille, C. Itié, J. Debroas

5°. IRA: Institut Universitaire de Radiophysique Appliquée, SwitzerlandM. Sans, N. Ruiz, J.Mezzo, M. Tosic

6°. UPC: Universitat Politècnica de Catalunya, SpainM. Ginjaume, A. Carnicer, X. Ortega

7°. CEA-LIST: Laboratoire National Henri Becquerel, FranceJ.M.Bordy, J. Daures, M. Desnozière

8°. SMU: Slovak Medical University, Slovak RepublicD. Nikodemova, M. Fulop

9°. NIOM: Nofer Institute of Occupational Medicine, PolandJ. Jankowski, J. Domienik, M. Brodecki

10°. BfS: Federal Office of Radiation Protection, GermanyA. Rimpler, I. Barth

11°. Radcard, PolandS. Wach, P. Kocjan

12°. MGP Intruments (MGPi), FranceP. Martin, JL. Barrère

ORAMED: FP7 (02/2008-02/2011)

Objectives

Improve the knowledge on extremity and eye lens exposure in IR/IC and NM

Provide recommendations for optimization of working practices

Provide recommendations for optimization of the use of active personal dosemeters (APDs) in IR/IC

Develop training materials

Organization of ORAMED: 5 work packages

Extremity and eye lens dosimetry in IR/ICMain achievements1329 measurements (x 8 dosemeters) in 6 EU countries, > 40 hospitals/roomsTypes of procedures:

IC:CA/PTCA, RFA, PM/ICDIR:DSA/PTA LL, Re, Ca/Ce

EmbolizationERCP

Analysis of the parameters influencing the dosesRoom protective equipment – Tube configuration –Catheter access

Monte Carlo simulations

Recommendations

Study of the influence of each parameter separately

Main results

Personal protective equipment (lead apron, thyroid collar) are widely used, leaded glasses for ~30%.

No room protective equipment is used for ~25% of cases.

Large spread of doses are observed.

For IR and IC, embolization and PM/ICD lead to the highest doses, respectively.

Left wrist and finger are the positions with highest doses (closest to the scattering center). However, whenrespective annual limits are taken into account, the left eye position become more important.

Effect of the room protective equipmenton doses is smaller than (theoretically) expected.

Well designed and used room protective equipment are essential for a better protection.

Hand and eye doses are significantly higher for overcouch tube configurations (by 2-50 times) than forundercouch.

Hand and eye doses are higher for radial catheter access (by 2-7 times) than for femoral access.

Use of an automatic injector is associated with lower doses, by 4-16 times.

Extremity and eye lens dosimetry in IR/IC

Main results

Annual extrapolations:Frequency distribution for all procedures

(84 physicians)

Monitoring of the hands is recommended (especially for cardiology)

No need for leg monitoring if a table shield is properly used

Use of leaded glasses and monitoring of the eyes are recommended (except for ERCP)

New eye lens dose limit will be surpassed by many workers (near 50% ofcardiologists!)

Extremity and eye lens dosimetry in IR/IC

Eyes45-150

mSv; 8%

< 15mSv; 75%

15-45mSv; 17%

> 150mSv; 0%

Legs> 500

mSv; 1%

50-150mSv; 14%

< 50mSv; 81%

150-500mSv; 4%Wrists

150-500mSv; 6%

< 50mSv; 76%

50-150mSv; 18%

> 500mSv; 0%

Fingers150-500mSv; 2%

< 50mSv; 77%

50-150mSv; 17%

> 500mSv; 4%

Main achievements

Practical eye lens dosimetry in IR/IC

Proposal for eye lens dosemeter calibration and type testing for Hp(3)New phantom

Extensive calculations of conversion coefficients Hp(3)/Ka for photonsDesign and test of a dosemeter to measure Hp(3) (RADCARD)

Main achievements

8 commercially available APDs chosen

Use of active personal dosemeters in IR/IC

Tests:• in laboratory conditions, in continuous fields: dose, dose rate, energy and angular responses

• in laboratory conditions, in pulsed fields: dose rate, pulse frequency, pulse width

• at a medical X-ray facility (on phantom)

• in 7 European hospitals, in real conditions (102 measurements on operators, for 5 APDtypes out of 8)

Development of a prototype specifically designed for medical pulsed fields (MGPi)

Recommendations relating choice and use of APDs in IR/IC

ThermoEPD Mk2.3

Main results

In continuous X-ray beams: most APDs have correct behavior up to 10 Sv/h(according to IEC 61526 standard)

In pulsed X-ray beams: except for PM1621A, all APDs provide a reading.Limitations are mostly due to high dose rates rather than pulse frequency.

In hospital conditions: behavior more satisfactory than in laboratory conditions.Due to lower dose rates in the scattered field.

On operators: slight (by 20-30%) dose underestimation with respect to a passivedosemeter.

It is not recommended to use APDs as ‘legal dosimeters’ in IR/IC.

Use of active personal dosemeters in IR/IC

Extremity dosimetry in nuclear medicineMain achievements735 measurements (x 22 dosemeters) in 7 EU countries, 34 NM departments, for 124 workers99mTc, 18F, 90Y-Zevalin® (+ others)Preparation and administration stagesIdentification of good and bad practicesAnalysis of the parameters influencing the dosesMonte Carlo simulations (~200) for realistic scenarios (voxel phantoms)

Recommendations

99mTc preparationRange: 33 – 2062 µSv/GBqMean: 432 µSv/GBqN=36

18F administrationRange: 139 – 4113

µSv/GBqMean: 933 µSv/GBqN=30

18F administrationRange: 97 – 4433

µSv/GBqMean: 1205 µSv/GBqN=30

99mTc administrationRange: 12 – 951 µSv/GBqMean: 233 µSv/GBqN=32

Worker

Max

imum

Hp(

0.07

) [µ

Sv/G

Bq]

Main resultsLarge spread of doses is observed. Due to: practice, individual habit.

Bad practices are clearly associated with high doses, so are good practices with low doses.

Preparation leads to higher doses than administration.

Extremity dosimetry in nuclear medicine

18F preparation

Bad practices

0

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

2400

Maxim

um ann

ual dose (m

Sv)

Workers

Tc‐99m administration

Tc‐99m preparation

F‐18 administration

F‐18 preparation

Main results

Ratios between the maximum dose and dose at possible locations for routine monitoring

Good correlation are found between the maximum dose and doses at positions used for routinering dosemeters

Hand monitoring

Routine ring dosemeter shall be located at the base of the index finger of the non-dominant hand with the sensitive part of the dosemeter oriented towards the inside ofthe hand.For estimation of the maximum hand dose: multiply by 6

Extremity dosimetry in nuclear medicine

0

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

2400T6HB1

T9HB1

T2HF7

T3HF7

T6HD2

T7HD2

T3HD1

T1HD4

T10H

F2 

T8HB1

T3HA2

T12H

F2 

T3HE2

T3HD2

T2HD4

T11H

F2 

T2HE2

T9HF2

T6HF7

T1HF7

T1HG4

T2HG4

T10H

E1T4HF2

T9HE1

T2HB1

T7HA2

T1HE3

T2HE3

T1HD3

T4HE2

T1HD2

T5HD2

T5HF7

T4HF7

T1HE3

T5HE1

T1HB1

T7HB1

T6HE1

T3HE3

T7HE1

T2HD2

T2HG5

T1HG5

T8HF2 

T5HE2

T4HG2

T3HG2

T5HF2

T6HA2

T4HB3

T2HB3

T1HB3

T2HA2

T3HB3

T4HB1

T3HE1

T1HE1

T1HF3

T6HD1

T1HD1

T2HD1

T1HA1

T3HA1

T2HF4

T1HF4

Maxim

umannu

aldo

se(m

Sv)

2976

6994

9898

Annual dose estimationTc‐99m

 ad

ministration

Tc‐99m

 prep

aration

F‐18

 ad

ministration

F‐18

 prep

aration

D < 150 mSv 49% 

150 mSv < D < 500 mSv 31% 

D > 500 mSv 19% 

More than

one

proced

ure

• Some workers were monitored for only one type of procedure forthe ORAMED project when actually they performed more. In thesecases, the estimation of the annual dose has been calculated onlyconsidering the monitored procedures, from which real measuredvalues were available.

ORAMED

Extensive dosimetric study on RP of medical staff, covering:

IR/IC and NM

Extremities, eye lens, whole-body

Measurements / MC simulations

Developments by manufacturers

Dissemination and training

ORAMED workshop, 20-21/01/2011, UPC, Barcelona, Spain

Training materials

Recommendations / guidelines: practical

> 20 publications + many presentations

Contacts with scientific organizations and networks, standard organizations…

Conclusions

Thank you for your attention!

Acknowledgment to the European Atomic Energy Community's Seventh Framework Programme for funding the ORAMED project under grant agreement n° 211361.

www.oramed-fp7.eu