The influence of environmental crisis perception and trait anxiety on the level of eco-worry and climate anxiety.

Eco-anxiety, which refers to the anxiety experienced in response to worsening environmental conditions, is a growing global phenomenon. Climate change anxiety, due to the escalating impact of ongoing climate change, stands out as the most commonly recognized form of eco-anxiety. Nevertheless, numerous uncertainties persist regarding the relationship of this eco-anxiety response to pro-environmental behaviors, as well as its connection with trait anxiety and the perception of the environmental crisis.

Dose assessment following an overexposure of a worker at a Swiss nuclear power plant.

Aim: The aim of this work was to assess the doses received by a diver exposed to a radiation source during maintenance work in the fuel transfer pool at a Swiss nuclear power plant, and to define whether the statutory limit was breached or not.

Method: Onsite measurements were carried out and different scenarios were simulated using the MicroShield Software and the MCNPX Monte Carlo radiation transport code to estimate the activity of the irradiating object as well as the doses to the limbs and the effective dose delivered to the operator.

Results: The activity of the object was estimated to 1.

EXPOSURE OF THE SWISS POPULATION BY RADIODIAGNOSTICS: 2013 REVIEW.

In 2013, a nationwide investigation was conducted in Switzerland to establish the population's exposure from medical X rays. A hybrid approach was used combining the Raddose database accessible on-line by the participating practices and the Swiss medical tariffication system for hospitals. This study revealed that the average annual number of examinations is 1.

Monte Carlo simulation of a whole-body counter using IGOR phantoms.

Whole-body counting is a technique of choice for assessing the intake of gamma-emitting radionuclides. An appropriate calibration is necessary, which is done either by experimental measurement or by Monte Carlo (MC) calculation. The aim of this work was to validate a MC model for calibrating whole-body counters (WBCs) by comparing the results of computations with measurements performed on an anthropomorphic phantom and to investigate the effect of a change in phantom's position on the WBC counting sensitivity.

Exposure of the Swiss population to computed tomography.

Background: The frequency of CT procedures has registered a significant increase over the last decade, which led at the international level to an increasing concern on the radiological risk associated with the use of CT especially in paediatrics. This work aimed at investigating the use of computed tomography in Switzerland, following the evolution of CT frequency and dose data over a decade and comparing it to data reported in other countries.

Methods: The frequency and dose data related to CT are obtained by means of a nationwide survey.

Exploring the use of the Swiss medical tariffication codes (TARMED) in the establishment of the frequency of radiodiagnostic examinations.

In population surveys of the exposure to medical X-rays both the frequency of examinations and the effective dose per examination are required. The use of the Swiss medical tariffication system (TARMED) for establishing the frequency of X-ray medical examinations was explored. The method was tested for radiography examinations performed in 2008 at the Lausanne University Hospital.

Swiss population exposure to radiation by interventional radiology in 2008.

The aim of this study was to investigate the radiation exposure of the Swiss population to interventional procedures. A nationwide survey was conducted in Switzerland. The annual effective dose per capita due to interventional procedures was found to be 0.

Exposure of the Swiss population by medical x-rays: 2008 review.

Nationwide surveys on radiation dose to the population from medical radiology are recommended in order to follow the trends in population exposure and ensure radiation protection.The last survey in Switzerland was conducted in 1998,and the annual effective dose from medical radiology was estimated to be 1 mSv y j(-1) per capita. The purpose of this work was to follow the trends in diagnostic radiology between 1998 and 2008 in Switzerland and determine the contribution of different modalities and types of examinations to the collective effective dose from medical x-rays.

An audit of diagnostic reference levels in interventional cardiology and radiology: are there differences between academic and non-academic centres?

A wide variation in patient exposure has been observed in interventional radiology and cardiology. The purpose of this study was to investigate the patient dose from fluoroscopy-guided procedures performed in non-academic centres when compared with academic centres. Four procedures (coronary angiography, percutaneous coronary intervention, angiography of the lower limbs and percutaneous transluminal angioplasty of the lower limbs) were evaluated.

Patient doses in CT examinations in Switzerland: implementation of national diagnostic reference levels.

Diagnostic reference levels (DRLs) were established for 21 indication-based CT examinations for adults in Switzerland. One hundred and seventy-nine of 225 computed tomography (CT) scanners operated in hospitals and private radiology institutes were audited on-site and patient doses were collected. For each CT scanner, a correction factor was calculated expressing the deviation of the measured weighted computed tomography dose index (CTDI) to the nominal weighted CTDI as displayed on the workstation.

Criteria for establishing shielding of multi-detector computed tomography (MDCT) rooms.

The aim of this work is to compare two methods used for determining the proper shielding of computed tomography (CT) rooms while considering recent technological advances in CT scanners. The approaches of the German Institute for Standardisation and the US National Council on Radiation Protection and Measurements were compared and a series of radiation measurements were performed in several CT rooms at the Lausanne University Hospital. The following three-step procedure is proposed for assuring sufficient shielding of rooms hosting new CT units with spiral mode acquisition and various X-ray beam collimation widths: (1) calculate the ambient equivalent dose for a representative average weekly dose length product at the position where shielding is required; (2) from the maximum permissible weekly dose at the location of interest, calculate the transmission factor F that must be taken to ensure proper shielding and (3) convert the transmission factor into a thickness of lead shielding.

Fluoroscopy-guided procedures in cardiology: is patient exposure being reduced over time?

The number of fluoroscopy-guided procedures in cardiology is increasing over time and it is appropriate to wonder whether technological progress or change of techniques is influencing patient exposure. The aim of this study is to examine whether patient dose has been decreasing over the years. Patient dose data of more than 7700 procedures were collected from two cardiology centres.

Quality initiatives* radiation risk: what you should know to tell your patient.

The steady increase in the number of radiologic procedures being performed is undeniably having a beneficial impact on healthcare. However, it is also becoming common practice to quantify the health detriment from radiation exposure by calculating the number of cancer-related deaths inferred from the effective dose delivered to a given patient population. The inference of a certain number of expected deaths from the effective dose is to be discouraged, but it remains important as a means of raising professional awareness of the danger associated with ionizing radiation.

[Cardiac radiological investigations: what risks for the patients?].

The volume of diagnostic or therapeutic procedures in cardiology requiring the use of ionizing radiation is continuously increasing. While most examinations involve doses relatively low and thus add a low risk to the process itself, there are situations where the doses exceed the dose where excess risk of death from cancer has been statistically demonstrated. In addition, some complex procedures can result in the emergence of deterministic effects such as burns to the skin.

CT radiation dose in children: a survey to establish age-based diagnostic reference levels in Switzerland.

This work aimed at assessing the doses delivered in Switzerland to paediatric patients during computed tomography (CT) examinations of the brain, chest and abdomen, and at establishing diagnostic reference levels (DRLs) for various age groups. Forms were sent to the ten centres performing CT on children, addressing the demographics, the indication and the scanning parameters: number of series, kilovoltage, tube current, rotation time, reconstruction slice thickness and pitch, volume CT dose index (CTDI(vol)) and dose length product (DLP). Per age group, the proposed DRLs for brain, chest and abdomen are, respectively, in terms of CTDI(vol): 20, 30, 40, 60 mGy; 5, 8, 10, 12 mGy; 7, 9, 13, 16 mGy; and in terms of DLP: 270, 420, 560, 1,000 mGy cm; 110, 200, 220, 460 mGy cm; 130, 300, 380, 500 mGy cm.

CT dose optimization when changing to CT multi-detector row technology.

The purpose of this article was to review the strategies to control patient dose in adult and pediatric computed tomography (CT), taking into account the change of technology from single-detector row CT to multi-detector row CT. First the relationships between computed tomography dose index, dose length product, and effective dose in adult and pediatric CT are revised, along with the diagnostic reference level concept. Then the effect of image noise as a function of volume computed tomography dose index, reconstructed slice thickness, and the size of the patient are described.

Neutron measurements around storage casks containing spent fuel and vitrified high-level radioactive waste at ZWILAG.

Spectrometric and dosimetric measurements were made around a cask containing spent fuel and a cask containing high-level radioactive waste at the Swiss intermediate waste and spent fuel storage facility. A Bonner sphere spectrometer, an LB 6411 neutron monitor and an Automess Szintomat 6134A were used to characterise the n-gamma fields at several locations around the two casks. The results of these measurements show that the neutron fluence spectra around the cask containing radioactive waste are harder and higher in intensity than those measured in the vicinity of the spent fuel cask.

Exposure of the Swiss population by radiodiagnostics: 2003 review.

A nationwide investigation was conducted in Switzerland to establish the exposure of the population by medical x rays and update the results of the 1998 survey. Both the frequency and the dose variations were studied in order to determine the change in the collective dose. The frequency study addressed 206 general practitioners (GPs), 30 hospitals, and 10 private radiology institutes.

How to set up and apply reference levels in fluoroscopy at a national level.

A nationwide survey was launched to investigate the use of fluoroscopy and establish national reference levels (RL) for dose-intensive procedures. The 2-year investigation covered five radiology and nine cardiology departments in public hospitals and private clinics, and focused on 12 examination types: 6 diagnostic and 6 interventional. A total of 1,000 examinations was registered.

Number of X-ray examinations performed on paediatric and geriatric patients compared with adult patients.

The age of the patient is of prime importance when assessing the radiological risk to patients due to medical X-ray exposures and the total detriment to the population due to radiodiagnostics. In order to take into account the age-specific radiosensitivity, three age groups are considered: children, adults and the elderly. In this work, the relative number of examinations carried out on paediatric and geriatric patients is established, compared with adult patients, for radiodiagnostics as a whole, for dental and medical radiology, for 8 radiological modalities as well as for 40 types of X-ray examinations.

Impact of the introduction of 16-row MDCT on image quality and patient dose: Phantom study and multi-centre survey.

The purpose was to compare the image quality and patient dose between 4- and 16-row MDCT units and to evaluate the dispersion of the dose delivered for common clinical examinations. Four 4- and 16-row MDCT units were used in the study. Image noise levels from images of a CatPhan phantom were compared for all units using a given CTDI(vol) of 15.

[CT utilisation in Switzerland: frequency and secular trends].

Purpose: This study analyzes CT examinations in Switzerland.

Materials And Methods: Using different sources (administrative data on the equipment, a 1998 nationwide inquiry into practices, and data provided by the Swiss University Hospitals of Basel, Zurich, and Lausanne), we determined the frequency of CT examinations (hospitals and private radiologists) in 1998 according to different descriptive variables and studied the progression in CT use over time.

Results: CT scanners increased by 7% between 1998 and 2004.

Diagnostic and interventional radiology: a strategy to introduce reference dose level taking into account the national practice.

The purpose of this study is to present a strategy to define the reference dose levels for fluoroscopic, dose-intensive examinations. This work is a part of the project of the Federal Office of Public Health of Switzerland to translate the guidelines of the International Commission on Radiological Protection and the European Union into action. The study will also be used to set reference dose levels on the basis of a national survey.

Optimisation in stereotactic radiosurgery of AVMs: II. Comparison of arc and MMLC therapy.

Two stereotactic surgery methods, arc and micro-multileave collimator (MMLC) therapy, were compared in the particular case of arteriovenous malformations (AVMs) treatment. Different methods of the treatment optimisation were used. The comparison covered a group of 22 patients suffering from peripheral and central AVMs of different sizes who underwent initially arc therapy.

Optimisation in stereotactic radiosurgery of AVMs: I. Mathematical considerations.

One forward-planning method and five inverse-planning methods for optimisation of treatment in radiation therapy were compared in the particular case of radiosurgery with micro-multi-leaves collimator (MMLC) and arc therapy. The "manual" method, two matrix methods (singular value decomposition and non-negative least square fit), two gradient methods (quasi-Newton and conjugate gradient algorithms) and the "simulated annealing" stochastic method were investigated. The performance of these methods was assessed in terms of the speed of convergence to an optimum, the ability to account for the organs at risk, and probability of targeted success.