Computer-aided treatment planning greatly improves the therapeutical index in radiotherapy. However, treatment plans need to be registered with the actual patient position on the treatment device before therapeutical irradiation can be started. Registration is commonly carried out by comparing a set of 2D control radiographs of the patient, the so-called portal images (PI), with 2D synthetic ra...

OBJECTIVE To assess the impact of CT slice index and thickness (3 mm versus 5 mm) on (i) prostate volume, dimensions, and isocenter coordinates, (ii) bladder and rectal volumes, and (iii) DRR quality, in the treatment of prostate cancer. METHODS 16 patients with prostate cancer underwent two planning CT-scans using 3 and 5 mm slice index/thickness. Prostate, bladder, and rectum were outlined ...

Abstract. Reducing disaster risk is critical to securing the ambitions of Sustainable Development Goals (SDGs), and natural hazard scientists make a key contribution achieving this aim. Understanding Earth processes dynamics underpins analysis, which (alongside analysis other drivers) informs actions required manage reduce risk. Here we suggest how research can better contribute planning develo...

The purpose of this study was to evaluate a custom portal image - digitally reconstructed radiograph (DRR) registration software application. The software works by transforming the portal image into the coordinate space of the DRR image using three control points placed on each image by the user, and displaying the fused image. In order to test statistically that the software actually improves ...

Digital Tomosynthesis (DTS) is an image modality in reconstructing tomographic images from two-dimensional kV projections covering a narrow scan angles. Comparing with conventional cone-beam CT (CBCT), it requires less time and radiation dose in data acquisition. It is feasible to apply this technique in patient positioning in radiotherapy. To facilitate its clinical application, a software too...

The virtual private network (VPN) provides customers with predictable and secure network connections over a shared network infrastructure. The recently proposed hose model for VPNs has desirable properties in terms of greater flexibility and better multiplexing gain. However, the ‘classic’ fair bandwidth allocation scheme introduces the issue of low overall utilisation in this model; furthermor...

Registration of 2-D projection images and 3-D volume images is still a largely unsolved problem. In order to register a pre-operative CT image to an intra-operative 2-D x-ray image, one typically computes simulated x-ray images from the attenuation coefficients in the CT image (Digital Reconstructed Radiograph, DRR). The simulated images are then compared to the actual image using intensity-bas...

The Sendai Framework for Disaster Risk Reduction (DRR) 2015-2030 is the first of three United Nations (UN) landmark agreements this year (the other two being the Sustainable Development Goals due in September 2015 and the climate change agreements due in December 2015). It represents a step in the direction of global policy coherence with explicit reference to health, economic development, and ...

BACKGROUND To determine the role of postmastectomy radiotherapy (PMRT) in breast cancer patients with T1-2 and N1 disease. PATIENTS AND METHODS A total of 207 postmastectomy women were enrolled. The 5-year Kaplan-Meier estimates of locoregional recurrence rate (LRR), distant recurrence rate (DRR) and overall survival (OS) were analyzed by different tumor characteristics. Multivariate analyses...

The El Niño Southern Oscillation (ENSO) cycle is often blamed for disasters in Pacific island communities. From a disaster risk reduction (DRR) perspective, the challenges with the El Niño part of the ENSO cycle, in particular, are more related to inadequate vulnerability reduction within development than to ENSO-induced hazard influences. This paper analyses this situation, filling in a concep...