Patient - Ultrasound Interaction. latest developments and efforts in medical ultrasound safety topics and bio-effects research.

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2 Patient - Ultrasound Interaction latest developments and efforts in medical ultrasound safety topics and bio-effects research.

3 Patient - Ultrasound Interaction Edited by Ladislav Doležal Faculty of Medicine and Dentistry, Palacký University, Olomouc, CZ Christian Kollmann Center for Medical Physics & Biomedical Engineering, Medical University Vienna, A

4 List of contributors in alphabetical order Wendy Berkers Cablon Medical B.V., Leusden, NL Jacinta E. Browne BSc. MSc. PhD. CPhys. School of Physics, Medical Ultrasound Group, Dublin Institute of Technology, Dublin, IRL Ing. Ladislav Doležal, PhD. Palacký University in Olomouc, Faculty of Medicine, Olomouc, CZ Dr. Andrew Hurrell, PhD., BSc (Hons) Precision Acoustics Ltd, Dorchester, UK Dipl.-Ing. Cosima Koch Vienna University of Technology, Institute of Chemical Technologies and Analytics, Vienna, A cosima.koch@tuwien.ac.at RNDr. Hana Kolářová, PhD. Palacký University in Olomouc, Faculty of Medicine, Olomouc, CZ kol@tunw.upol.cz Dr. Ing. Christian Kollmann Medical University of Vienna, Center for Medical Physics & Biomedical Engineering, UltraSound-Lab, Vienna, A christian.kollmann@meduniwien.ac.at Dipl.-Ing. Stefan Radel, PhD. Vienna University of Technology, Institute of Applied Physics, Vienna, A radel@tuwien.ac.at Ing. Kateřina Tománková, PhD. Palacký University in Olomouc, Faculty of Medicine, Olomouc, CZ katerina.tomankova@ upol.cz Dr. Ing. Friedrich Überle Hamburg University of Applied Sciences, Faculy of Life Sciences, Biomedical Technology Department, Hamburg, D friedrich.ueberle@haw-hamburg.de

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6 Preface Ultrasound has been used for more than 60 years clinically, mainly not only in the modality of diagnostic imaging but also as a therapeutical method. Since very early on, it was and still is the aim of many scientists to understand and clarify the mechanism of interactions between the emitted ultrasound pulses and biological tissues. These efforts have ensured that ultrasound is regarded today as tone of the safest imaging modality in use clinically. Ultrasound societies, congresses and conferences have discussed and published the latest research results, concerning the ultrasound interactions with biological tissues. This along with the highlighting of relevant safety guidelines and policies emphasis the important merits they deserve. One of these conferences called Patient Ultrasound Interaction (Pacient A Ultrazvuk), has its origins and sitting in the Czech Republic. It is a biannual meeting of clinicians and reseachers exchanging ideas, results and practical aspects, especially discussing the bio-effect and interrelations, mostly within a smaller group of specialists. Some of the topics and talks that were presented in the last conference of 2008, have been selected and form in part the content of this book. However, the main aim of the book, in particular the concern of both editors, is the collating of the latest research results and meanings of ultrasound-induced bio-effects, interactions and related safety issues.

7 Therefore the book is structured in two parts; - clinical issues and - technical-practical issues to bio-effects and medical device safety topics. Last but not least the editors would like to thank - the sponsors: Cablon Medical B.V., Precision Acoustics Ltd. and foundation Péče o ženu o.p.s., - the manuscript reviewers - Dr. Robert Morrison for grammactical correction - Mgr. Jaromír Vachutka for his patient work on formatting layout of this book. Without their support we would not have been able to publish and issue this small book! Ladislav Doležal Christian Kollmann (Editors) Olomouc and Vienna, September 2010

8 Contents 1 Ultrasound Bio-Safety survey for practicians - the current ECMUS policy ( Christian Kollmann) Ultrasound interactions Mechanical interactions Thermal interactions 1.2 Epidemiological investigations and adverse biological effects 1.3 Potential risk rating for different ultrasound imaging modes 1.4 Indices to estimate the potential risk Mechanical Index (MI) Thermal Index (TI) Survey of TI / MI-values measured in routine scanning 1.5 ECMUS Recommendations for routine use Clinical Safety Statement Souvenir images 1.6 Practical ultrasound exposure estimation, safety awareness and safety related equipment maintenance 1.7 References 2 Methods for Ultrasound Scanners Performance Evaluation (Ladislav Doležal) 2.1 Standards and official recommendations 2.2 Methods used for quality performance assessment of ultrasound scanners and their parameters Simple ( paperclip or coin ) method

9 2.2.2 Daily Tests Test objects for evaluation First Call aperio Irradiated acoustic pressure determination by use of hydrophone Point Spread Function (PSF) method The methods comparison 2.3 References 3 Ultrasound Image Quality Assurance Using a Signal-to-Noise Measurement Method ( Friedrich Überle) Efforts towards increasing US image quality assurance Ultrasound Image Parameters 3.3 Sources of failures and degradation of ultrasound imagers US transducer failures Standard Tests for US imagers 3.4 Materials and Methods Construction of the test phantom Measurement procedure Automated evaluation of the measurement results Interpretation of the measurement results 3.5 Pilot Study Materials and Methods Results 3.6 Discussion 3.7 Conclusions

10 3.8 References 4 Quality control of ultrasound equipment with UltraIQ software ( Wendy Berkers) History 4.2 General information 4.3 Image import 4.4 Usability with commercial test objects 4.5 Actual developments and advantages 4.6 How to perform a QA check 4.7 Summary 5 Automated measurements for ultrasonic QA (Andrew Hurrell) Measurement tank Scanning rig Data acquisition Tank lining Water treatment Hydrophones Membrane hydrophones Needle hydrophones Fibre-optic hydrophones Data processing Voltage-to-pressure conversion Acoustic output parameters Quantifying spatial variation

11 5.3.4 Reporting References 99 6 Doppler Performance Testing: Is it hitting the mark? (Jacinta E. Browne) Review of current Doppler Performance Test Procedures Continuous Wave and Pulsed Wave Doppler Performance Test Protocols Colour and Power Doppler Performance Test Protocols Colour and Power Doppler Tissue Mimicking Phantoms and Test Objects New Technology Conclusions References Ecological competence of yeast suspensions in acoustic filters (Stefan Radel and Cosima Koch) Ultrasonic particle manipulation Ultrasonic resonator Radiation forces Ultrasonically Enhanced Settling The h-shape separator Methods Suspensions Assessment Microscopy Handling Experiments 132

12 7.3.1 Influence of US on yeast cells kept in pressure nodes Damage to yeast cells in inter-nodal space Influence of US on yeast cells in h-shape Conclusions Viable filtration Damaging streaming Replication References The effect of Photodynamic and Sonodynamic treatment on B16FO cell line (Kateřina Tománková and Hana Kolářová) Materials and Methods Materials and instruments Photodynamic and Sonodynamic therapy Microscopic study Measurement of ROS production Cancer cell cytotoxicity assay Results and Discussion References 168

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