Conclusions

Radia,on Protec,on

1 Department for Radiology and Neuroradiology, Bundeswehr Central Hospital, D-56072 Koblenz2 Bundeswehr Institute for Radiobiology, D-80937 Munich

3 Institute of Neuroradiology, University Hospital Mainz, D-55131 Mainz

Conclusions

Purpose

A B C

Procedures in the Interven/onal Radiology do o5en come with high dose burdens but represent excellent therapy op/ons in a variety of severe diseases.Therefore, dose reduc/on for pa/ents as well as medical staff is pivotal for the success and acceptance of interven/onal procedures. Implementa/on ofmodern technical and organiza/onal measures can help reduce administered doses and comply to na/onal and interna/onal regula/ons.

SANITÄTSDIENST

Doses and Regula,ons

Radiation exposure in the Interventional Radiology – risk and fate of advanced procedures

Benjamin V. Becker1, Julian Schneider1, Hanns Leonhard Kaatsch2, Carolin Brockmann3, Marc A. Brockmann3, Stephan Waldeck1

Advanced procedures in the interven/onal radiology are becoming more important and more frequently used especially in the treatment of several acute life-threatening injuries like stroke or aor/c rupture [1]. Technical advantages led to a broader spectrum of possible interven/ons and complex procedures but didalso come with a higher exposure to ionizing radia/on. In 2016, 3% of overall radiological procedures were interven/onal vascular procedures but counted for18% of total administered dose [2]. Besides determinis/c effects, e.g. erythema in pa/ents who underwent interven/onal procedures, individual riskassessment of possible stochas/c effects has to be weighed up against the an/cipated benefits of the therapy itself [3]. However, harmful effects of theadministered dose are not limited to the pa/ent but can also affect the radiologist and the medical staff [4]. Especially the development of cataracts ininterven/onalists is a rising maTer of concern [5]. Furthermore, long-term stochas/c effects of repeated and prolonged x-ray exposure have long beenneglected by radiologists but have come into focus during recent years [6]. With all this in mind, great efforts have been made to reduce exposi/on levels forpa/ents and staff by means of technical measures, but also personal protec/on equipment and organiza/onal measures.

Literature:1. Miller, D. L. (2008). Overview of contemporary interven?onal fluoroscopy procedures. Health physics, 95(5), 638-644.2. Bundesamt für Strahlenschutz; https://www.bfs.de/DE/themen/ion/anwendung-medizin/diagnostik/roentgen/haeufigkeit-exposition.html; accessed 05.Apr.20213. Loose, R. W., Popp, U., Wucherer, M., & Adamus, R. (2010). Medizinische Strahlenexposition und ihre Rechtfertigung an einem Großklinikum: Vergleich von strahlungs-und krankheitsbedingtem Risiko. RöFo, 182(01), 66-70.4. Parikh, J. R., Geise, R. A., Bluth, E. I., Bender, C. E., Sze, G., Jones, A. K., & Human Resources Commission of the American College of Radiology. (2017). Poten?al radia?on-related effects on radiologists. American Journal of Roentgenology, 208(3), 595-602.5. Vano, Eliseo, et al. Radia?on-associated lens opaci?es in catheteriza?on personnel: results of a survey and direct assessments. Journal of Vascular and Interven?onal Radiology 24.2 (2013): 197-204.6. Parikh, Jay R., et al. Poten?al radia?on-related effects on radiologists. American Journal of Roentgenology 208.3 (2017): 595-602.7. Vano, E., et al. Pa?ent dose in interven?onal radiology: a European survey. Radia?on protec?on dosimetry 129.1-3 (2008): 39-45.8. Loose, Reinhard, et al. (2020). The new radia?on protec?on framework since 2019–Implementa?on in Germany and comparison of some aspects in seven European countries. RöFo. 192(11). 9. Walz, Michael, Michael Wucherer, and Reinhard Loose. "Was bringt die neue Strahlenschutzverordnung?." Der Radiologe 59.5 (2019): 457-466.10. Adamus, R., et al. Strahlenschutz in der interven?onellen Radiologie. Der Radiologe 56.3 (2016): 275-281.

Some rules do always apply to keep the dose “as low as reasonablyachievable”: keep exposure TIME low, maximize DISTANCE to X-ray tube anduse SHIELDING for protec/on measures. The best way to reduce exposure/me is omicng an obsolete interven/on. Pulsed fluoroscopy and techniqueslike “care posi/on”, “last image hold”, “road map” and “overlay” alsodecrease exposure /me and are rou/nely used. Maximizing the distance issome/mes not possible in an interven/on but especially during high-doseprocedures (e.g., cone beam CT) the interven/onalist should maximize thedistance to the pa/ent. Shielding can further reduce scaTered radia/onexposure for the medical staff (Fig.1). Furthermore, personal protec/onequipment includes shielding (Fig.2) but also personal dosimetry is essen/alfor op/mal radia/on protec/on. Impact of several protec/on measures in theInterven/onal Radiology is given in Table 1.

Radia/on doses in the Interven/onal Radiology can vary many-fold based onthe procedure and used equipment but especially because of pa/entcharacteris/cs [7]. German reference values for interven/onal procedures aregiven in Table 2.Na/onal regula/ons in Europe are based on the European Council Direc/veEURATOM/2013/59 but transposed differently by the member states [8].Important changes of the revised regula/ons in Germany (since 2018) arelower lens dose limit for interven/onalists (150 -> 20 mSv/a), the requirementfor dose management systems and the par/cipa/on of a medical physicist forhigh-dose applica/ons [9].

Figure 1: Modern angiography suite with transparent acryl-glass leadshielding (cealing mounted, barrier, over-/under-table)

Figure 2: Personal protec/on equipment (glasses (0.75 mmPb), thyroid-gland protec/on, vest and skirt, cap (all 0.50mm Pb).

Measure Dose reductionShieldingTable < 64%Ceiling mounted 50-96.7%Personal protection equipment 70-89.3%

OperationalPulse rate (10 -> 5 p/s) 50%Filtering + collimator + low-dose protocol < 95%

Table 1: Dose reduction measures (selection) [10]

Procedure DAP (µGy * m2)Endovascular clot retrieval (brain) 18.000Endovascular cerebral aneurysm repair 25.000

Endovascular aneurysm repairthoracic aorta 23.000infrarenal aorta 23.000suprarenal aorta 23.000

TACE - transarterial chemoembolization 23.000

PTA - percutanous transluminal angioplastypelvis 9.000upper leg/popliteal 4.000lower leg/feet 2.500

Table 2: German reference values for interventional procedures