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As the COVID-19 spread continues to challenge the societal and professional norms, radiotherapy around the globe is pushed into an unprecedented transformation. We will discuss how clinical physics has transformed to ascertain safety and quality standards across four facilities around the world through diversity of action, innovation, and scientific flexibility.

There has been an ongoing technological evolution and impact of medical instrumentation on cardiovascular patient care during the last fifty years, and it is now impossible to manage the diagnostic and therapeutic process without adequate instrumental support. This trend has radically modified the professional activity of most healthcare personnel but it has not always been flanked by appropriate professional training. In particular, professional nursing schools are resistant to open their courses to technological aspects and in the rare cases of interest, have major difficulties finding qualified teachers with clinical experience and an aptitude for instrumental procedures

Introduction The Abdus Salam International Centre for Theoretical Physics (ICTP) and the Trieste University have initiated in 2014 a Master of Advanced Studies in Medical Physics a two-years training programme in Medical Physics. The programme is designated to provide young promising graduates in physics, mainly from developing countries, with a post-graduated theoretical and clinical training suitable to be recognised as Clinical Medical Physicist in their countries. Presently, the 3 cycles of the programme has seen 49 participants from 33 Countries: Africa (19), Asia (11), Central and South America (14), and Europe (5), selected from more than 400 applicants per year. Scholarships are awarded to candidates from developing countries with support of the IAEA, TWAS, KFAS, IOMP, EFOMP and ICTP. Material and methods The programme is developed following the recommendations of IOMP and IAEA for education and clinical training. In the first year 332 lectures and 228 h of exercises are devoted to all main fields of medical physics. The second year is spent in one of the 12 medical physics department of the hospitals’ network for the clinical training in: radiation oncology or diagnostic and nuclear medicine, on a programme developed adapting the IAEA (TCS37, TCS47 and TCS50) and AFRA guidelines. Conclusions IOMP, EFOMP and IAEA are seeing this initiative as an answer to the growing demand of Medical Physicists in developing Countries, representing an important European contribution to the development of medical physics in the developing world.

Neurodegenerative diseases are frequently associated with structural changes in the brain. Magnetic Resonance Imaging (MRI) scans can show these variations and therefore be used as a supportive feature for a number of neurodegenerative diseases. The hippocampus has been known to be a biomarker for Alzheimer disease and other neurological and psychiatric diseases. However, it requires accurate, robust and reproducible delineation of hippocampal structures. Fully automatic methods are usually the voxel based approach, for each voxel a number of local features were calculated. In this paper we compared four different techniques for feature selection from a set of 315 features extracted for each voxel: (i) filter method based on the Kolmogorov-Smirnov test; two wrapper methods, respectively, (ii) Sequential Forward Selection and (iii) Sequential Backward Elimination; and (iv) embedded method based on the Random Forest Classifier on a set of 10 T1-weighted brain MRIs and tested on an independent set of 25 subjects. The resulting segmentations were compared with manual reference labelling. By using only 23 features for each voxel (sequential backward elimination) we obtained comparable state of-the-art performances with respect to the standard tool FreeSurfer., Comment: To appear on "Computational and Mathematical Methods in Medicine", Hindawi Publishing Corporation. 19 pages, 7 figures

Scanned ion beam therapy of lung tumors is severely limited in its clinical applicability by intrafractional organ motion, interference effects between beam and tumor motion (interplay), as well as interfractional anatomic changes. To compensate for dose deterioration caused by intrafractional motion, motion mitigation techniques, such as gating, have been developed. However, optimization of the treatment parameters is needed to further improve target dose coverage and normal tissue sparing. The aim of this study was to determine treatment-planning parameters that permit to recover good target coverage for each fraction of lung tumor treatments. For 9 lung tumor patients from MD Anderson Cancer Center (Houston, Texas), a total of 70 weekly time-resolved computed tomography (4DCT) datasets, which depict the evolution of the patient anatomy over the several fractions of the treatment, were available. Using the GSI in-house treatment planning system TRiP4D, 4D simulations were performed on each weekly 4DCT for each patient using gating and optimization of a single treatment plan based on a planning CT acquired prior to treatment. The impact on target dose coverage (V 95%,CTV) of variations in focus size and length of the gating window, as well as different additional margins and the number of fields was analyzed. It appeared that interfractional variability could potentially have a larger impact on V 95%,CTV than intrafractional motion. However, among the investigated parameters, the use of a large beam spot size, a short gating window, additional margins, and multiple fields permitted to obtain an average V 95%,CTV of 96.5%. In the presented study, it was shown that optimized treatment parameters have an important impact on target dose coverage in the treatment of moving tumors. Indeed, intrafractional motion occurring during the treatment of lung tumors and interfractional variability were best mitigated using a large focus, a short gating window, additional margins, and three fields.

Synchrotron radiation (SR) therapy is a promising alternative to treat brain tumors, whose management is limited due to the high morbidity of the surrounding healthy tissues. Several approaches are being explored by using SR at the European Synchrotron Radiation Facility (ESRF), where three techniques are under development Synchrotron Stereotactic Radiation Therapy (SSRT), Microbeam Radiation Therapy (MRT) and Minibeam Radiation Therapy (MBRT).The sucess of the preclinical studies on SSRT and MRT has paved the way to clinical trials currently in preparation at the ESRF. With this aim, different dosimetric aspects from both theoretical and experimental points of view have been assessed. In particular, the definition of safe irradiation protocols, the beam energy providing the best balance between tumor treatment and healthy tissue sparing in MRT and MBRT, the special dosimetric considerations for small field dosimetry, etc will be described. In addition, for the clinical trials, the definition of appropiate dosimetry protocols for patients according to the well established European Medical Physics recommendations will be discussed. Finally, the state of the art of the MBRT technical developments at the ESRF will be presented. In 2006 A. Dilmanian and collaborators proposed the use of thicker microbeams (0.36-0.68 mm). This new type of radiotherapymore » is the most recently implemented technique at the ESRF and it has been called MBRT. The main advantage of MBRT with respect to MRT is that it does not require high dose rates. Therefore it can be more easily applied and extended outside synchrotron sources in the future.« less

In this paper we generalize the approach of Ahonen et al (1993 IEEE Trans. Biomed. Eng. 40 859-69) to two-dimensional non-uniform sampling. The focus is on two main topics: (1) searching for the optimal sensor configuration on a planar measurement surface; and (2) reconstructing the magnetic field (a continuous function) from a discrete set of data points recorded with a finite number of sensors. A reconstruction formula for Bz is derived in the framework of the multidimensional Papoulis generalized sampling expansion (Papoulis A 1977 IEEE Trans. Circuits Syst. 24 652-4, Cheung K F 1993 Advanced Topics in Shannon Sampling and Interpolation Theory (New York: Springer) pp 85-119) in a particular case. Application of these considerations to the design of biomagnetic sensor arrays is also discussed.