Search results for " Radiation."
showing 10 items of 2788 documents
Complete written/oral information about dose exposure in CT: is it really useful to guarantee the patients' awareness about radiation risks?
2018
Aims and objectives: According to the European directive 2013/59/Euratom, starting from February 2018, the information relating to patient exposure will be part of computed tomography (CT) reports, but the impact of this information on patients has not been deeply evaluated. Aim of our study was to evaluate patients’ perception of radiation exposure related to routine CT and their understanding after communication of their dose exposure. Materials and methods: A survey, investigating patient’s knowledge of radiation dose, was given to all adult patients (> 18 years) undergoing a CT examination both before and after CT scan. The first survey was the same for all patients. After CT scan, a se…
Chemically and electrically induced sweating and flare reaction
2004
Both thin afferent (nociceptors) and efferent (sympathetic sudomotor) nerve fibers can be activated electrically and chemically, resulting in neurogenic erythema and sweating. These reactions have been used before to assess the impairment of sympathetic and nociceptor fibers in humans. In this study, electrically induced sweating and erythema were assessed simultaneously in the foot dorsum and thigh, and were compared to chemically induced activation. Reproducible intensity-response relations (stimulation intensities 0-30 mA, 1 Hz) were obtained from 32 subjects. The steepest increase of the sweat response was induced at lower intensities as compared to that of the erythema (18.3 mA vs. 25.…
Hypo-fractionated stereotactic radiation therapy for lung malignancies by means of helical tomotherapy: report of feasibility by a single-center expe…
2018
Background: Several experiences in the literature report SBRT as an effective treatment option for medically inoperable early stage non-small cell lung cancer (NSCLC) and oligometastatic disease. The optimal fractionation schedules and total dose remain controversial. In this study, we evaluated the safety in terms of toxicity and efficacy of using of 8â10 fractions schedules with Helical Tomotherapy (HT) for primary and metastatic lung lesions. Methods: Between March 2014 and May 2016, a total of 39 patients (median age 72 years, range 26â91) were treated with HT-SBRT for malignant lung lesions: 22 patients with early stage NSCLC, 17 with oligometastases. Patients received 8â10 fract…
A Cohort Study of Childhood Cancer Incidence after Postnatal Diagnostic X-Ray Exposure
2009
Ionizing radiation is an established cause of cancer, yet little is known about the health effects of doses from diagnostic examinations in children. The risk of childhood cancer was studied in a cohort of 92.957 children who had been examined with diagnostic X rays in a large German hospital during 1976-2003. Radiation doses were reconstructed using the individual dose area product and other exposure parameters, together with conversion coefficients developed specifically for the medical devices and standards used at the radiology department. Newly diagnosed cancers occurring between 1980 and 2006 were determined through record linkage to the German Childhood Cancer Registry. The median ra…
Is ultraviolet exposure acquired at work the most important risk factor for cutaneous squamous cell carcinoma? Results of the population-based case-c…
2018
Background Squamous cell carcinoma (SCC) is among the most frequent types of cancer constituting a significant public health burden. Prevention strategies focus on limiting UV-exposure during leisure time. However, the relative impact of occupational and non-occupational UV-exposure for SCC occurrence is unclear. Objectives To investigate the association between occupational and non-occupational UV-exposure with SCC in a multicenter population-based case-control study hypothesizing that high occupational UV-exposure increases the risk for SCC. Methods Consecutive patients with incident SCC (n=632) were recruited from a German national dermatology network. Population-based controls (n=996) w…
Performance of the compensation comparison method for retinal straylight measurement: effect of patient's age on repeatability
2008
Aim: The assessment of repeatability and reproducibility of retinal straylight measurements with the C-Quant straylight meter (Oculus AG, Germany) and the effect of patient’s age on the instrument performance are tested with a series of experiments. Methods: First, 20 eyes from 20 subjects (mean age 26.9 (SD 2.7) years, mean refractive error −1.34 (2.72) D) were examined with the C-Quant straylightmeter, taking 10 consecutive readings. Five subjects were also examined on five consecutive days to assess reproducibility. Additionally, repeated measures of straylight from 84 subjects of ages ranging from 19 to 86 years (mean (SD): 42.4 (24.0) years) were retrospectively analysed to assess the …
The Intracranial Distribution of Gliomas in Relation to Exposure From Mobile Phones: Analyses From the INTERPHONE Study
2016
When investigating the association between brain tumors and use of mobile telephones, accurate data on tumor position are essential, due to the highly localized absorption of energy in the human brain from the radio-frequency fields emitted. We used a point process model to investigate this association using information that included tumor localization data from the INTERPHONE Study (Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden, and the United Kingdom). Our main analysis included 792 regular mobile phone users diagnosed with a glioma between 2000 and 2004. Similar to earlier results, we found a statistically significant association …
Stereotactic fractionated irradiation of optic nerve sheath meningioma: a new treatment alternative
2002
Background: Primary optic nerve sheath meningioma (ONSM) is a rare but almost invariably blinding tumour when its natural history is observed in a “wait and see” strategy. Surgery has hitherto only been advocated in case of progressive disease involving intracranial structures, as it leads to iatrogenic blindness in the overwhelming majority of cases. Therefore, treatment options bearing lesser risk of functional deterioration are highly desirable, both in cases of intracranial involvement as well as during earlier phases of the disease which are currently generally left untreated. The authors report the outcome of the largest series of patients to date treated by stereotactic fractionated …
Covariation of spectral and nonlinear EEG measures with alpha biofeedback.
2002
Item does not contain fulltext This study investigated how different spectral and nonlinear EEG measures covaried with alpha power during auditory alpha biofeedback training, performed by 13 healthy subjects. We found a significant positive correlation of alpha power with the largest Lyapunov-exponent, pointing to an increased dynamical instability of the EEG accompanying alpha enhancement. Alpha power amplification, moreover, was significantly correlated with a decrease of spectral entropy within the alpha range. This outcome reflects a sharpening of the alpha peak during biofeedback training. The fact that the sharpening effect clearly preceded the increase of alpha amplitude could be exp…
Spectral transmission of the pig lens: Effect of ultraviolet A+B radiation
2014
Summary Objective To determine the spectral transmission curve of the crystalline lens of the pig. To analyse how this curve changes when the crystalline lens is irradiated with ultraviolet A + B radiation similar to that of the sun. To compare these results with literature data from the human crystalline lens. Procedures We used crystalline lenses of the common pig from a slaughterhouse, i.e. genetically similar pigs, fed with the same diet, and slaughtered at six months old. Spectral transmission was measured with a Perkin-Elmer Lambda 35 UV/VIS spectrometer. The lenses were irradiated using an Asahi Spectra Lax-C100 ultraviolet source, which made it possible to select the spectral emissi…