Towards a novel small animal proton irradiation platformthe SIRMIO project Background: Precision small animal radiotherapy research is a young emerging field aiming to provide new experimental insights into tumour and tissue models in different microenvironments, to unravel the complex mechanisms of radiation damage in target and non-target tissues and assess the efficacy of novel therapeutic strategies. To this end, for photon therapy, modern small animal radiotherapy research platforms have been developed over the last years and are meanwhile commercially available. Conversely, for proton therapy, which holds a great potential for an even superior outcome than photon therapy, no commercial system exists yet. Material and methods: The project SIRMIO (Small Animal Proton Irradiator for Research in Molecular Image-guided Radiation-Oncology) aims at realizing and demonstrating an innovative portable prototype system for precision small animal proton irradiation, suitable for integration at existing clinical treatment facilities. The proposed design combines precise dose application with novel insitu multi-modal anatomical image guidance and in-vivo verification of the actual treatment delivery for precision small animal irradiation. Results and conclusions: This manuscript describes the status of the different components under development, featuring a dedicated beamline for degradation and focusing of clinical proton beams, along with novel detector systems for insitu imaging. The foreseen workflow includes pre-treatment proton transmission imaging for treatment planning and position verification, complemented by ultrasonic tumour localization, followed by image-guided delivery with on-site range verification by means of ionoacoustics (for pulsed beams) and positronemission-tomography (PET, for continuous beams). The proposed compact and cost-effective system promises to open a new era in small animal proton therapy research, contributing to the basic understanding of in-vivo radiation action to identify areas of potential breakthroughs in radiotherapy for future translation into innovative clinical strategies.

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Several techniques are under development for image-guidance in particle therapy. Positron (β+) emission tomography (PET) is in use since many years, because accelerated ions generate positron-emitting isotopes by nuclear fragmentation in the human body. In heavy ion therapy, a major part of the PET signals is produced by β+-emitters generated via projectile fragmentation. A much higher intensity for the PET signal can be obtained using β+-radioactive beams directly for treatment. This idea has always been hampered by the low intensity of the secondary beams, produced by fragmentation of the primary, stable beams. With the intensity upgrade of the SIS-18 synchrotron and the isotopic separation with the fragment separator FRS in the FAIR-phase-0 in Darmstadt, it is now possible to reach radioactive ion beams with sufficient intensity to treat a tumor in small animals. This was the motivation of the BARB (Biomedical Applications of Radioactive ion Beams) experiment that is ongoing at GSI in Darmstadt. This paper will present the plans and instruments developed by the BARB collaboration for testing the use of radioactive beams in cancer therapy.

Objectives: To develop a real-time dose-monitoring system to measure the patient's eye lens dose during neuro-interventional procedures. Methods: Radiation dose received at left outer canthus (LOC) and left eyelid (LE) were measured using Metal-Oxide-Semiconductor Field-Effect Transistor dosimeters on 35 patients who underwent diagnostic or cerebral embolization procedures. Results: The radiation dose received at the LOC region was significantly higher than the dose received by the LE. The maximum eye lens dose of 1492 mGy was measured at LOC region for an AVM case, followed by 907 mGy for an aneurysm case and 665 mGy for a diagnostic angiography procedure. Strong correlations (shown as R2) were observed between kerma-area-product and measured eye doses (LOC:0.78, LE: 0.68). Lateral and frontal air-kerma showed strong correlations with measured dose at LOC (AKL:0.93, AKF:0.78) and a weak correlation with measured dose at LE. A moderate correlation was observed between fluoroscopic time and dose measured at LE and LOC regions. Conclusions: The MO Skin dose-monitoring system represents a new tool enabling real-time monitoring of eye lens dose during neuro-interventional procedures. This system can provide interventionalists with information needed to adjust the clinical procedure to control the patient's dose. Key Points • Real-time patient dose monitoring helps interventionalists to monitor doses.• Strong correlation was observed between kerma-area-product and measured eye doses.• Radiation dose at left outer canthus was higher than at left eyelid

This paper discusses six most frequent methods used to extract different features in Electrocardiograph (ECG) signals namely Autoregressive (AR), Wavelet Transform (WT), Eigenvector, Fast Fourier Transform (FFT), Linear Prediction (LP), and Independent Component Analysis (ICA). The study reveals that Eigenvector method gives better performance in frequency domain for the ECG feature extraction.

The MOSkin detector proved to be reliable when exposed to different field sizes, SSDs, depths in solid water, dose rates, frame rates, and radiation incident angles within a clinical x-ray beam. The MOSkin detector with water equivalent depth equal to 0.07 mm is a suitable detector for in vivo skin dosimetry during interventional radiology procedures.

In the phantom setting, both techniques demonstrated a significant correlation to the true bifurcation angle. Despite the lack of agreement of the two techniques in the clinical context, our findings in phantoms suggest that MPR should be preferred to VRT for the measurement of coronary bifurcation angle by CCTA.

Study has been made of the thermoluminescence (TL) response of silica-based Ge-doped cylindrical, flat and photonic crystal fibres (referred to herein as PCF-collapsed) to electron (6, 12 and 20 MeV) and photon (6, 10 MV) irradiation and 1.25 MeV γ-rays, for doses from 0.1 Gy to 100 Gy. The electron and photon irradiations were delivered through use of a Varian Model 2100C linear accelerator located at the University of Malaya Medical Centre and γ-rays delivered from a 60Co irradiator located at the Secondary Standard Dosimetry Laboratory (SSDL), Malaysian Nuclear Agency. Tailor-made to be of various dimensions and dopant concentrations (6–10% Ge), the fibres were observed to provide TL yield linear with radiation dose, reproducibility being within 1–5%, with insensitivity to energy and angular variation. The sensitivity dependency of both detectors with respect to field size follows the dependency of the output factors. For flat fibres exposed to 6 MV X-rays, the 6% Ge-doped fibre provided the greatest TL yield while PCF-collapsed showed a response 2.4 times greater than that of the 6% Ge-doped flat fibres. The response of cylindrical fibres increased with core size. The fibres offer uniform response, high spatial resolution and sensitivity, providing the basis of promising TL systems for radiotherapy applications.