Search results for "radioterapia"

[Diagnosis, prognosis and treatment of "myocardial bridging": state of the art and unresolved issues].

2013

The current gold standard for the diagnosis of myocardial bridging is conventional coronary angiography; however, it shows only indirect signs of the disease, due to the systolic compression of the artery caused by the myocardial bridge with narrowing of the lumen and diastolic relaxation. On the other hand, computed tomography coronary angiography, even though exposing to radiation, clearly demonstrates the intramural course, the overlying muscular bands and the surrounding tissues also in asymptomatic patients and in absence of systolic compression. The prognosis of patients with myocardial bridge is usually good, but further studies are needed to evaluate the long-term prognosis of these…

A mistaken case of non-q wave acute infarction

2012

Over the last few years, enormous progress has been made in Cardiovascular imaging. Myocarditis is today an underdiagnosed cause of acute sudden death, heart failure, and chronic dilated cardiomyopathy. Its diagnosis is frequently missed or delayed and it can simulate an acute coronary syndrome because of its clinical presentation and elevation of cardiac enzymes. Cardiac Magnetic Resonance has become the leading modality for its noninvasive diagnosis, and it often replaces endomyocardial biopsy in clinical practise.

Usefulness of SonoVue in the identification of sentinel nodes in patients with breast cancer

2013

Purpose Methods and Materials Results Conclusion References Personal Information

Implications of irradiating the subventricular zone stem cell niche

2016

Radiation therapy is a standard treatment for brain tumor patients. However, it comes with side effects, such as neurological deficits. While likely multi-factorial, the effect may in part be associated with the impact of radiation on the neurogenic niches. In the adult mammalian brain, the neurogenic niches are localized in the subventricular zone (SVZ) of the lateral ventricles and the dentate gyrus of the hippocampus, where the neural stem cells (NSCs) reside. Several reports showed that radiation produces a drastic decrease in the proliferative capacity of these regions, which is related to functional decline. In particular, radiation to the SVZ led to a reduced long-term olfactory memo…

Neuroimaging delle Demenze

2012

Sin dai suoi esordi la diagnostica per immagini ha profondamente rivoluzionato la diagnostica neurologica. Tecniche quali la tomografia computerizzata (TC) e la risonanza magnetica (RM) si sono, nel corso degli anni, rivelate di enorme vantaggio per i pazienti affetti da patologie neurologiche. Tuttavia, quello delle malattie neurodegenerative con particolare riferimento alle demenze, tra i tanti capitoli delle neuroscienze, è quello che probabilmente ha meno usufruito dei vantaggi offerti dalla diagnostica neuroradiologica “convenzionale”. Sebbene negli ultimi due/tre lustri le apparecchiature TC ed RM abbiano infatti subito una forte spinta evolutiva complice l'irrefrenabile progresso te…

Spectrum of non-cardiac collateral findings in patients with suspected coronary artery disease assessed with Multislice Computed Tomography Coronary …

2009

Dosimetry for electron Intra-Operative RadioTherapy: Comparison of output factors obtained through alanine/EPR pellets, ionization chamber and Monte …

2015

Abstract In this work a comparison between the response of alanine and Markus ionization chamber was carried out for measurements of the output factors (OF) of electron beams produced by a linear accelerator used for Intra-Operative Radiation Therapy (IORT). Output factors (OF) for conventional high-energy electron beams are normally measured using ionization chamber according to international dosimetry protocols. However, the electron beams used in IORT have characteristics of dose per pulse, energy spectrum and angular distribution quite different from beams usually used in external radiotherapy, so the direct application of international dosimetry protocols may introduce additional uncer…

Correlation between ferrous ammonium sulfate concentration, sensitivity and stability of Fricke gel dosimeters exposed to clinical X-ray beams

2014

Abstract This work describes the characterization of various Fricke-Agarose-Xylenol gels (FXG) dosimeters using NMR relaxometry and MRI analysis. Using X-rays from a clinical linear accelerator (LINAC), the gels were irradiated in the dose range from 0 Gy to 20 Gy. The photon sensitivity of the FXGs was measured in terms of NMR relaxation rates; its dependence on radiation dose was determined as a function of ferrous ammonium sulfate contents (from 0.5 mM to 5 mM). Furthermore, the stability of the NMR signal was monitored over several days after irradiation. These measurements were aided by Magnetic Resonance Imaging (MRI) scans which allowed three-dimensional (3D) dose mapping. In order t…

Analysis of spatial diffusion of ferric ions in PVA-GTA gel dosimeters through magnetic resonance imaging

2017

Abstract This work focused on the analysis of the temporal diffusion of ferric ions through PVA-GTA gel dosimeters. PVA-GTA gel samples, partly exposed with 6 MV X-rays in order to create an initial steep gradient, were mapped using magnetic resonance imaging on a 7T MRI scanner for small animals. Multiple images of the gels were acquired over several hours after irradiation and were analyzed to quantitatively extract the signal profile. The spatial resolution achieved is 200 μm and this makes this technique particularly suitable for the analysis of steep gradients of ferric ion concentration. The results obtained with PVA-GTA gels were compared with those achieved with agarose gels, which …

Analysis of the response of PVA-GTA Fricke-gel dosimeters with clinical magnetic resonance imaging

2018

Abstract Fricke gel dosimeters produced with a matrix of Poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA) were analyzed with magnetic resonance imaging (MRI). Previous studies based on spectrophotometry showed valuable dosimetric features of these gels in terms of X-ray sensitivity and diffusion of the ferric ions produced after irradiation. In this study, MRI was performed on the gels at 1.5 T with a clinical scanner in order to optimize the acquisition parameters and obtain high contrast between irradiated and non-irradiated samples. The PVA gels were found to offer good linearity in the range of 0–10 Gy and a stable signal for several hours after irradiation. The sensitivi…