Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Simple measurement method from Dresden improves accuracy in proton beam therapy


Proton beams are new high-precision weapons in the fight against cancer. However, uncertainty with regard to the range of the beams has prevented the full exploitation of the potential of this method until now. Researchers all over the world are therefore looking for ways to measure the exact range during a course of treatment. Scientists at the National Center for Radiation Research in Oncology – OncoRay and at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have succeeded in developing a surprisingly simple solution. Initial preclinical tests have already gone well.

A proton beam is similar to a bullet in that it has a certain projectile range. The power of destruction of the charged particles is greatest shortly before they stop. "The effect could be concentrated on a specific point in a human body – in our case on a tumor," explained Dr. Guntram Pausch of the OncoRay center.

Tumors can be precisely targeted with proton beam therapy. Dresden-based scientists are looking for ways of monitoring the course of the beam in real time.


"In this way it is possible to inflict severe damage on the diseased cells and yet leave the surrounding healthy tissue unscathed." The depth of penetration depends on the initial speed of the beams and the composition of the tissue – and herein lies the challenge, as the radiation expert explained.

"Even a trifle like a stuffed nose in the preliminary examination can distort the data for the treatment plan and, later on, this will mean that the beam will not stop right on target. Therefore we have to consider safety margins around the tumor during the treatment."

Up to now it has only been possible to reduce this element of uncertainty with the aid of computed tomography before the treatment or indirectly by assessing the effect of the radiation after the treatment. This is why the Dresden-based scientists are looking for a way to measure the range of the particle beam in real time. Gamma radiation is thought to be a helpful means in this respect.

This type of radiation is generated by nuclear reactions triggered by the protons on their journey through the tissue. "The existing methods attempt to measure this gamma radiation using complex and expensive detector systems in order to track the journey of the protons," said Pausch, summarizing the latest research endeavors. "It will take another few years before this can be used in the hospitals."

He developed, therefore, together with Dr. Fine Fiedler of the Helmholtz-Zentrum Dresden-Rossendorf and her team an alternative method called "Prompt Gamma Timing". This new method is based on a time measurement for which just one detector is needed.

Rapid identification of nonconformities

The scientists focus on a fundamental physical effect: the protons need a certain amount of time to reach the place where they develop their greatest destruction potential. With the new method they, therefore, measure the time span between the point at which the beam enters the body and the point at which the gamma radiation hits the detector. "If the measured time spectra differ from the ones previously calculated, then the beam does not hit its target with sufficient accuracy," added Pausch.

"In this case we would notice this immediately, and could adapt the radiation to the new parameters." In order to confirm their assumptions, the researchers tested the method with the world market leader in proton beam therapy systems, Ion Beam Applications (IBA).

To do this, they went to the West German Proton Therapy Centre in Essen where they treated test objects with proton beams as normally used in radiation therapy. In these experiments the scientists were able to detect deviations of just a few millimeters with their method. On this basis, the safety margins around the tumor could be decreased, the effectiveness of the treatment increased, and at the same time healthy tissue could be still better protected.

However, the researchers also studied factors which may limit the accuracy of the method, as Guntram Pausch explained. Nevertheless, he sees great potential for the approach. "As the experiments have shown, our method could be applied in order to rule out appreciable deviations from the treatment plan during the therapy."

Guntram Pausch, whose OncoRay group "In-vivo Dosimetry for New Types of Radiation" is funded by the German Federal Ministry of Education and Research (BMBF), sees in the new technology a fast and feasible way of providing a method of treatment verification for clinical use.

"Our approach could tide us over until more elaborate detector systems have been developed and tested." Until the end of this year, Pausch and his team want to conduct tests on phantoms, which model the human tissue and organ structure. Should the method also prove reliable in these trials, it could soon make the leap to day-to-day clinical practice.

Background: The University Hospital Carl Gustav Carus Dresden is the first institute in Eastern Germany to back radiotherapy with protons in the fight against cancer. The first courses of treatment on tumor patients began in the middle of December 2014. The plan is now to expand the capacity gradually to 400 to 500 patients per year.

There are two other university hospitals in Germany besides Dresden which are offering the proton beam therapy, namely the Heidelberg Ion-Beam Therapy Center and the West German Proton Therapy Centre in Essen. The Dresden complex is used for both patient care and for research. Therefore, the University Hospital Carl Gustav Carus has joined forces with the OncoRay center and the HZDR to form the University Proton Therapy Dresden (UPTD).

F. Hueso-González, W. Enghardt, F. Fiedler, C. Golnik, G. Janssens, J. Petzoldt, D. Prieels, M. Priegnitz, K. Römer, J. Smeets, F. Vander Stappen, A. Wagner, G. Pausch, „First test of the prompt gamma ray timing method with heterogeneous targets at a clinical proton therapy facility”, Physics in Medicine and Biology 60 (2015) 6247–6272 (DOI:10.1088/0031-9155/60/16/6247)

_Further information:
Dr. Guntram Pausch
National Center for Radiation Reseach in Oncology – OncoRay
Phone +49 351 458-7414 | E-Mail:

Dr. Fine Fiedler
Institute of Radiation Physics at HZDR
Phone +49 351 260-2973 | E-Mail:

_Media contact:
Simon Schmitt | Science editor
Phone +49 351 260-3400 | E-Mail:
Helmholtz-Zentrum Dresden-Rossendorf
Bautzner Landstr. 400 | 01328 Dresden, Germany |

The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is conducting research in the areas of energy, health, and matter. The following set of questions provides the focal point for this research:

• How can energy and resources be utilized in an efficient, safe, and sustainable way?
• How can malignant tumors be more precisely visualized, characterized, and more effectively treated?
• How do matter and materials behave under the influence of strong fields and in smallest dimensions?

Since 2011, the HZDR has been a member of the Helmholtz Association, Germany's largest scientific organization. Some 1,100 employees are working at one of four research sites in Dresden, Leipzig, Freiberg, and Grenoble/France - approximately 500 of HZDR employees are scientists, including 150 Ph.D. students.

Weitere Informationen:

Simon Schmitt | Helmholtz-Zentrum Dresden-Rossendorf

Further reports about: HZDR Radiation accuracy detector gamma radiation healthy tissue proton beam protons treatment plan

More articles from Medical Engineering:

nachricht Gentle sensors for diagnosing brain disorders
29.09.2016 | King Abdullah University of Science and Technology

nachricht New imaging technique in Alzheimer’s disease - opens up possibilities for new drug development
28.09.2016 | Lund University

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>