ASSESSMENT OF OCCUPATIONAL EXPOSURE IN THE MAIN PAEDIATRIC INTERVENTIONAL RADIOLOGY PROCEDURES.

The aim of this study is to evaluate the personal dose equivalent Hp(10) in the most frequent (non-cardiac) paediatric interventional radiology (PIR) procedures: central venous catheters (CVC), hepatic/biliary and sclerotherapy interventions. i2 active solid-state dosemeters placed over the lead apron were used to monitor the exposure of three interventional radiologists over 18 months. A database was created to register all procedures performed by each radiologist (including the type of procedure and the kerma-area product, PKA).

Role of correlated noise in textural features extraction.

Predictive models of tumor response based on heterogeneity metrics in medical images, such as textural features, are highly suggestive. However, the demonstrated sensitivity of these features to noise does affect the model being developed. An in-depth analysis of the noise influence on the extraction of texture features was performed based on the assumption that an improvement in information quality can also enhance the predictive model.

A randomized, double blind, single dose, comparative study of the pharmacokinetics, safety and immunogenicity of MB02 (bevacizumab biosimilar) and reference bevacizumab in healthy male volunteers.

Aims: The pharmacokinetic (PK) similarity between MB02, a proposed bevacizumab biosimilar, and reference bevacizumab approved from the USA (US-bevacizumab) and European Union (EU-bevacizumab) was evaluated. Safety and immunogenicity were also assessed.

Methods: In this phase 1, randomized, double blind, single dose, parallel group study, 114 healthy male volunteers were randomized 1:1:1 to receive a 3 mg/kg intravenous dose of MB02, US-bevacizumab or EU-bevacizumab, and evaluated for 100 days.

Occupational doses to the eye lens in pediatric and adult noncardiac interventional radiology procedures.

Purpose: To assess occupational lens exposure in a mixed interventional radiology department, comparing pediatric and adult procedures. To analyze the correlation between the lens dose and the doses measured at the chest and collar level and the kerma-area product (P ).

Methods: For 17 months, three radiologists performing both pediatric and adult interventions were monitored by means of 14 dosimeters per worker: 12 single-point optically stimulated luminescent (OSL) dosimeters calibrated in terms of H (0.

Local diagnostic reference levels for paediatric non-cardiac interventional radiology procedures.

Purpose: To establish local diagnostic reference levels (DRLs) for non-cardiac interventional procedures in paediatrics.

Methods: The type of procedure, the patient's weight and age and dose-related data from 279 interventions was recorded in a database completed by interventional radiologists, radiographers and technicians of the Medical Physics department. These procedures were classified into 14 categories and 6 weight ranges.

Eye lens radiation exposure in paediatric interventional treatment of retinoblastoma.

Retinoblastoma represents 3% of cancers in children under fifteen years of age. The standard paediatric treatment for saving the affected eye is supraselective intra-arterial chemotherapy performed in interventional rooms. In order to address the radiation toxicity due to the angiography, the aim of this study was to determine the typical dose value corresponding to the procedure, estimate the paediatric patients' eye lens dose and study the relationship between dose indicators and dose to the lens.

Bevacizumab biosimilar BEVZ92 versus reference bevacizumab in combination with FOLFOX or FOLFIRI as first-line treatment for metastatic colorectal cancer: a multicentre, open-label, randomised controlled trial.

Background: BEVZ92 is a proposed biosimilar to bevacizumab. The two molecules have similar physicochemical and functional properties in in-vitro and preclinical studies. In this clinical study, we compared the pharmacokinetic profile, efficacy, safety, and immunogenicity of BEVZ92 with reference bevacizumab as a first-line treatment in patients with metastatic colorectal cancer.

Segmentation improvement through denoising of PET images with 3D-context modelling in wavelet domain.

Positron emission tomography (PET) images have been incorporated into the radiotherapy process as a powerful tool to assist in the contouring of lesions, leading to the emergence of a broad spectrum of automatic segmentation schemes for PET images (PET-AS). However, not all proposed PET-AS algorithms take into consideration the previous steps of image preparation. PET image noise has been shown to be one of the most relevant affecting factors in segmentation tasks.

Eye lens dose levels in interventional rooms using simple phantom simulation, dose management software and Monte Carlo method of uncertainty assessment.

This paper presents a fast method to estimate the annual eye lens dose levels for interventional practitioners applying the Monte Carlo method of uncertainty assessment. The estimation was performed by placing an anthropomorphic phantom in the typical working position, and applying the habitually employed protocol. No radiation protection devices were considered in the simulation.

Characterization and simulation of noise in PET images reconstructed with OSEM: Development of a method for the generation of synthetic images.

Introduction: The goals of the study are to characterize imaging properties in 2D PET images reconstructed with the iterative algorithm ordered-subset expectation maximization (OSEM) and to propose a new method for the generation of synthetic images.

Material And Methods: The noise is analyzed in terms of its magnitude, spatial correlation, and spectral distribution through standard deviation, autocorrelation function, and noise power spectrum (NPS), respectively. Their variations with position and activity level are also analyzed.

Radiation dose optimisation for conventional imaging in infants and newborns using automatic dose management software: an application of the new 2013/59 EURATOM directive.

Unlabelled: Objective: The new 2013/59 EURATOM Directive (ED) demands dosimetric optimisation procedures without undue delay. The aim of this study was to optimise paediatric conventional radiology examinations applying the ED without compromising the clinical diagnosis.

Methods: Automatic dose management software (ADMS) was used to analyse 2678 studies of children from birth to 5 years of age, obtaining local diagnostic reference levels (DRLs) in terms of entrance surface air kerma.

Denoising of PET images by context modelling using local neighbourhood correlation.

Positron emission tomography (PET) images are characterised by low signal-to-noise ratio and blurred edges when compared with other image modalities. It is therefore advisable to use noise reduction methods for qualitative and quantitative analyses. Given the importance of the maximum and mean uptake values, it is necessary to avoid signal loss, which could modify the clinical significance.

[Target volume segmentation of PET images by an iterative method based on threshold value].

Objectives: An automatic segmentation method is presented for PET images based on an iterative approximation by threshold value that includes the influence of both lesion size and background present during the acquisition.

Material And Methods: Optimal threshold values that represent a correct segmentation of volumes were determined based on a PET phantom study that contained different sizes spheres and different known radiation environments. These optimal values were normalized to background and adjusted by regression techniques to a two-variable function: lesion volume and signal-to-background ratio (SBR).

Energy deposition by a 106Ru/106Rh eye applicator simulated using LEPTS, a low-energy particle track simulation.

The present study introduces LEPTS, an event-by-event Monte Carlo programme, for simulating an ophthalmic (106)Ru/(106)Rh applicator relevant in brachytherapy of ocular tumours. The distinctive characteristics of this code are the underlying radiation-matter interaction models that distinguish elastic and several kinds of inelastic collisions, as well as the use of mostly experimental input data. Special emphasis is placed on the treatment of low-energy electrons for generally being responsible for the deposition of a large portion of the total energy imparted to matter.