Stråleterapi og medisinsk fysikk

Vi har som mål å optimalisere og forbedre bruken av stråling fra medisinteknisk utstyr for bedre og mer skånsom diagnostikk og behandling.


1. Radiation during deep-inspiration breath hold protects the heart in patients with early-stage breast cancer.

Since the start in 2004, the overall goal of this project has been to establish radiotherapy techniques that reduce the radiation dose to the heart in breast cancer patients.

Many women with breast cancer are treated with radiotherapy. With the radiation techniques used earlier, parts of the heart came into the beam portals when treating the left breast. Radiation to the heart increases the possibility of developing heart disease and heart failure.

Our research has shown that radiation during deep inspiration decreases the dose to the heart, with a benefit seen in almost all patients. The technique also allows us to include the parasternal lymph nodes in the target volume of patients with left sided breast cancer, without compromising target volume coverage and with acceptable doses to the heart. In a collaborative study with the lung department, we found that pulmonary function tests could be used for the selection of patients who will have the largest benefit from such treatment. In our latest study we were able to show that modern dynamic techniques used in combination with respiratory controlled radiation therapy further reduced radiation dose to the heart. We have also investigated, in cooperation with Oslo University Hospital-Radium hospital, the long-term risk of secondary cancer in the contralateral breast by radiation therapy with and without respiratory controlled breathing.

Stavanger University Hospital was the first hospital in Norway to use respiratory controlled radiation therapy. Since February 2006, most breast cancer patients with left sided breast cancer have been treated with this technique.

Published papers:
i. A comparison of conventional and dynamic radiotherapy planning techniques for early-stage breast cancer utilizing deep inspiration breath-hold. Vikström J, Hjelstuen MH, Wasbø E, Mjaaland I, Dybvik KI. Acta Oncol. 2018 Oct; 57(10):1325-1330.  Epub 2018 Sep; 28:1-6.

ii. Pulmonary function tests - an easy selection method for respiratory-gated radiotherapy in patients with left-sided breast cancer. Hjelstuen MH, Mjaaland I, Vikström J, Madebo T, Dybvik KI. Acta Oncol. 2015 Jul; 54(7):1025-31. Epub 2014 Dec 31.

iii. Radiation during deep inspiration allows loco-regional treatment of left breast and axillary-, supraclavicular- and internal mammary lymph nodes without compromising target coverage or dose restrictions to organs at risk. Hjelstuen MH, Mjaaland I, Vikström J, Dybvik KI. Acta Oncol. 2012 Mar; 51(3):333-44. Epub 2011 Dec 16.

iv. Dose evaluation and risk estimation for secondary cancer in contralateral breast and a study of correlation between thorax shape and dose to organs at risk following tangentially breast irradiation during deep inspiration breath-hold and free breathing. Johansen S, Vikström J, Hjelstuen MH, Mjaaland I, Dybvik KI, Olsen DR. Acta Oncol. 2011 May; 50(4):563-8  Epub 2011 Mar 3.

v. Cardiac and pulmonary dose reduction for tangentially irradiated breast cancer, utilizing deep inspiration breath-hold with audio-visual guidance, without compromising target coverage. Vikström J, Hjelstuen MH, Mjaaland I, Dybvik KI. Acta Oncol. 2011 Jan; 50(1):42-50 Epub 2010 Sep 15.
Contact person: Mari Hjelstuen (

2. Participation in projects administered by the Danish Breast Cancer Cooperative Group

a) Hypofraktioneret versus normofraktioneret helbrystbestråling til lymfeknude-negative brystkræftpatienter:et randomiseret fase II studium

Published papers and abstracts:
i. Hypo- vs normofractionated radiation of early breast cancer in the randomised DBCG HYPO trial. Offersen BV, Jacobsen EH, Nielsen MH, Krause M, Stenbygaard L, Mjaaland I, Schreiber A, Kasti UM, Jensen MB, Overgaard J.  Radiother Oncol. 2016 Apr;119, Supplement1: S64-S65. Poster presentation at the ESTRO 35 congress.

ii. Hypo- vs normofractionated radiation therapy of early stage breast cancer in the randomized DBCG HYPO trial. Offersen BV, Nielsen HM, Jacobsen EH, Nielsen MH, Krause M, Stenbygaard L, Mjaaland I, Schreiber A, Jensen MB, Overgaard J.  European Journal of Cancer. 2017 Feb; 72 (Supplement 1): S9-S10. Oral presentation.

b) The Skagen Trial I:  Moderately hypofractionated loco-regional adjuvant radiation therapy of early breast cancer combined with a simultaneous integrated boost in patients with an indication for boost: DBCG HYPO II, a randomised clinically controlled trial.

Published papers and abstracts:
i. Quality assessment of delineation and dose planning of early breast cancer patients included in the randomized Skagen Trial 1. Francolini G, Thomsen MS, Yates ES, Kirkove C, Jensen I, Blix ES, Kamby C, Nielsen MH, Krause M, Berg M, Mjaaland I, Schreiber A, Kasti UM, Boye K, Offersen BV. Radiother Oncol. 2017 May;123(2):282-287. Epub 2017 Mar 25.

ii. Internal and external validation of an ESTRO delineation guideline - dependent automated segmentation tool for loco-regional radiation therapy of early breast cancer. Eldesoky AR, Yates ES, Nyeng TB, Thomsen MS, Nielsen HM, Poortmans P, Kirkove C, Krause M, Kamby C, Mjaaland I, Blix ES, Jensen I, Berg M, Lorenzen EL, Taheri-Kadkhoda Z, Offersen BV.  Radiother Oncol. 2016 Dec;121(3):424-430. Epub 2016 Sep 30.

iii. Dose plan quality in the DBCG HYPO trial: an evaluation of all dose plans included in the study EP-1936: Dose plan quality in the DBCG HYPO trial: an evaluation based on all treatment plans in the study. Thomsen MS, Berg M, Zimmermann S, Lutz CM, Makocki S, Jensen I, Hjelstuen M, Pensold S, Jensen M.-B, Offersen BV. Radiother Oncol. 2016 Apr;119:S918-S919. Poster presentation at the ESTRO 35 congress.

c) Patient selection for proton therapy of early breast cancer – the DBCG phase II study strategy.

Abstract submitted for presentation at the ESTRO 38 congress:
Patient selection for proton therapy of early breast cancer – the DBCG phase II study strategy. Stick LB, Lorenzen EL, Yates ES, Anandadas C, Andersen K, Aristei C, Byrne O, Hol S, Jensen I, Kirby A, Kirova YM, Marrazzo L, Matías-Pérez A, Nielsen MMB, Nissen HD, Oliveros S, Verhoeven K, Vikström J, Offersen BV.

d) Consensus on target volume delineation and treatment planning strategy for the DBCG RT Recon trial.

Published abstract:
Consensus on target volume delineation and treatment planning strategy for the DBCG RT Recon trial. Nissen HD, Yates ES, Andersen K, Boersma L, Boye K, Canter R, Coles C, Costa E, Daniel S, Ho S, Jensen I, Lorenzen EL, Mjaaland I, Nielsen MEK, Kaidar-Person O, Poortmans P, Vikström J, Webb J, Offersen BV. Radiother Oncol., 2018 Apr; 127(Supplement 1):S492–S494. Presented as poster at the ESTRO 37 congress.

e) The DBCG RT Natural trial: Partial breast versus no irradiation for women ≥ 60 years operated with breast​ conservation for early breast cancer, a clinically controlled randomized phase III trial.

New study, inclusion of patients in Norway starts in 2019.
Contact person: Ingvil Mjaaland,

3. MRI as ​​a tool to understand fatigue

Medical image analysis with focus on clinical immunology, fatigue and primary Sjögren’s syndrome. In collaboration with Clinical Immunology Research Group and Radiology Research Group at Stavanger University Hospital.

Published papers:
No structural cerebral MRI changes related to fatigue in patients with primary Sjögren’s syndrome. Hammonds, SK, Lauvsnes, MB, Dalen,I, Beyer, MK, Kurz, KD, Greve, OJ, Norheim, KB, Omdal, R. Rheumatology Advances in Practice, Volume 1, Issue 1, 1 January 2017, rkx007,
Contact person: Solveig K. Hammonds,

4. Image Quality​​​ Quantification and Control

Acquisition parameters in combination with reconstruction parameters are of importance when optimizing image quality. Our group has different projects in this aspect and has developed Open Source software (ImageQC) to be used for the analysis and research. The same software is used for all image quality control tasks performed annually and for the more frequent constancy tests.

Published papers:
Variations in MTF and NPS between CT scanners with two different IR algorithms and detectors. Rolstadaas L and Wasbø E. Biomed. Phys. Eng. Express 2018 4 025009

Utprøving av måleteknikk for kvantifisering av indre romlig oppløsning for gammakamera (Developing a procedure for quantifying intrinsic spatial resolution for gamma camera).
Ellen Wasbø, MedFys 2018 (Norwegian conference of medical physics)
Summary: A method where MTF and FWHM of the gamma camera is measured using the edge of Cu-plates placed on the surface of the detector. A point source is placed at a distance. In the project various pixel-sizes, dead-times and acquisition times was tested.

Contact person: Ellen Wasbø,

5. Ot​​her projects

Published papers:
Fra røntgen til CT ved myelomatose (From X-ray to CT with myelomatosis). Aasland EU and Schubert M. HMT 2015 Nov; 5: 34-35.

Contribution to patent: Radiation absorbing composition, G.L. Husebye



  • Forskningsgruppe for Klinisk immunologi, Stavanger universitetssjukehus.
  • Forskningsgruppe for radiologi, Stavanger universitetssjukehus.
    Avdeling for Radiologi, Stavanger universitetssjukehus.


  • Danish Breast Cancer Cooperative Group (DBCG)
  • The Skagen Group: Birgitte V. Offersen, Aarhus University Hospital, Mechthild Krause, Liesbeth Boersma, Anna Kirby, Charlotte Coles, Navita Somaiah, Youlia Kirova, Sophie Rivera, Hanne Melgaard Nielsen, Ingvil Mjaaland, Icro Meattini, John Yarnold, Philip Poortmans, Dan Lundstedt, Conny Vrieling, Cynthia Aristei, Astrid Scholten, Lise Thorsen, Trine Tramm, Jens Overgaard.



Ingvil Mjaaland


Kristin Helene Iversen

​Navn og tittel​Medisinsk fysikerspesialist innen​Arbeidsområde
​Kjell Ivar Dybvik,​Stråleterapi​Stråleterapi
​Mari H. B. Hjelstuen,​Stråleterapi​Stråleterapi
​Per Johan Vikstrøm, Cand.scient.​Stråleterapi​Stråleterapi
​David Byberg,​Stråleterapi​Stråleterapi
​Elisabeth Aasland,​Stråleterapi + Røntgendiagnostikk
​Kari Helland,​Røntgendiagnostikk​Røntgendiagnostikk
​Ellen Wasbø,​Stråleterapi​Røntgendiagnostikk + Nuklærmedisin (+ Stråleterapi)
​Solveig K. Hammonds, MSc ​Røntgendiagnostikk + MR-avbildning + Nuklærmedisin

Sist oppdatert 27.04.2023