Search results for "magnetic [charge]"

Is MRI imaging in pediatric age totally safe? A critical reprisal.

2017

Current radiological literature is strongly focussed on radiation imaging risks. Indeed, given there is a small but actual augment in cancer risk from exposure to ionizing radiation in children, it is important to understand what the risk of alternative techniques could be. We retrospectively review literature data concerning possible MR imaging risks, focussing on the biological effects of MR, sedation and gadolinium compound risks when dealing with infant patients. The main concerns can be summarized in: (1) Biological effects of non-ionizing electromagnetic fields (EMF) employed—whose mechanisms of interaction with human tissues are polarization, induced current, and thermal heating, res…

Anteil des frühen systolischen Flussanstiegs am antegrad fließenden Gesamtvolumen bei Phasenkontrast-Flussmessungen in Atemanhaltetechnik

2005

Purpose To evaluate the contribution of early systole for the assessment of antegrade aortic flow volume by breath-hold velocity-encoded magnetic resonance (MR) flow measurements. Materials and methods Expiratory breath-hold fast low-angle shot (FLASH) phase-contrast flow measurements (temporal resolution tRes 61 msec, shared phases) perpendicular to the proximal ascending aorta and short axis true fast imaging with steady-state precession (TrueFISP) cine MR ventriculometry (tRes 34.5 msec) were performed in ten healthy male volunteers on a 1.5 T MR system (Sonata, Siemens Medical Solutions). Antegrade aortic flow volume (AFV) and left ventricular stroke volume (LV-SV) were evaluated using …

EPR dosimetry intercomparison using smart phone touch screen glass

2014

International audience; This paper presents the results of an interlaboratory comparison of retrospective dosimetry using the electron paramagnetic resonance method. The test material used in this exercise was glass coming from the touch screens of smart phones that might be used as fortuitous dosimeters in a large-scale radiological incident. There were 13 participants to whom samples were dispatched, and 11 laboratories reported results. The participants received five calibration samples (0, 0.8, 2, 4, and 10 Gy) and four blindly irradiated samples (0, 0.9, 1.3, and 3.3 Gy). Participants were divided into two groups: for group A (formed by three participants), samples came from a homogene…

Up-to-date imaging review of paediatric soft tissue vascular masses, focusing on sonography

2019

The purpose of this article is to provide an up-to-date overview on imaging of paediatric vascular soft tissue masses, including both neoplastic and non-neoplastic lesions. We describe the-often challenging-imaging diagnosis-mainly performed by ultrasound (and secondarily by MRI) and differential diagnosis of vascular soft tissue lesions in children. We underline how important it is to determine whether a vascular anomaly has a regional vascular origin, or if there are other entities, ranging from benign to malignant lesions, which have flow-signal or blood degradation products. Even though clinical examination and patient's history are the first and indispensable steps in the initial diagn…

Meningiomas of the Space of the Cavernous Sinus

1996

During the years 1985 to 1992, we encountered 59 patients with meningiomas involving the space of the cavernous sinus. In 29 of these patients, meningiomas were primarily located within the space of the cavernous sinus and were operated on without mortality and with low morbidity. A small subtemporal surgical approach was favored, which allowed initial tumor resection from the posterior aspect, where the Parkinson's triangle is wide, thus avoiding the additional morbidity of large-scale approaches. According to the relationships of the all-important cranial nerves passing within the lateral wall of the cavernous sinus, we divided the primary intracavernous meningiomas into four types, which…

Arachnoidalzyste der Keilbeinhöhle

1998

BACKGROUND Arachnoid cysts of the paranasal sinus are rare. They have not been described yet in the sphenoid sinus. PATIENT AND METHOD Microscopic-endoscopic endonasal surgery of the sphenoid sinus was performed on a 34-year-old female with a history of chronic headaches and a suspected mucocele of the sphenoid sinus in computed tomography (CT) and magnetic resonance imaging (MRI) studies. An extended arachnoid cyst was found in the enlarged sphenoid sinus, which was obliterated with collagen, fibrin glue, and abdominal fat. RESULTS There were no complications after the operation, and 12 months later the patient is still free of symptoms. CONCLUSION Arachnoidal cysts present in CT and MRI a…

Critical role of cardiac magnetic resonance in the diagnosis of left-dominant arrhythmogenic cardiomyopathy: A paradigmatic case in a recreational mi…

2021

Prediction of N0 Irradiated Rectal Cancer Comparing MRI Before and After Preoperative Chemoradiotherapy

2017

Background: The prediction of lymph node status using MRI has an impact on the management of rectal cancer, both before and after preoperative chemoradiotherapy. Objective: The purpose of this study was to maximize the negative predictive value and sensitivity of mesorectal lymph node imaging after chemoradiotherapy because postchemoradiation node-negative patients may be treated with rectum-sparing approaches. Design: This was a retrospective study. Settings: The study was conducted at a tertiary care hospital. Patients: Sixty-four patients with locally advanced rectal cancer who underwent preoperative chemoradiotherapy and MRI for staging and the assessment of response were evaluated. Mai…

New advances in radiomics of gastrointestinal stromal tumors

2020

Gastrointestinal stromal tumors (GISTs) are uncommon neoplasms of the gastrointestinal tract with peculiar clinical, genetic, and imaging characteristics. Preoperative knowledge of risk stratification and mutational status is crucial to guide the appropriate patients' treatment. Predicting the clinical behavior and biological aggressiveness of GISTs based on conventional computed tomography (CT) and magnetic resonance imaging (MRI) evaluation is challenging, unless the lesions have already metastasized at the time of diagnosis. Radiomics is emerging as a promising tool for the quantification of lesion heterogeneity on radiological images, extracting additional data that cannot be assessed b…

Imaging funzionale per diffusione (DWI) e ischemia cerebrale in fase acuta: Potenzialità diagnostiche e confronto con metodiche convenzionali

1997

Stroke is the third leading cause of death and is a major cause of long-term disability. Neuroprotective treatment within a 4-hour «therapeutic window» has proved highly efficacious in reducing morbility and mortality in animal model. It is with this background that the need for emergent diagnosis and therapy of acute stroke in strongly suggested. Computed tomography (CT) shows the parenchymal changes of acute stroke too late to be helpful, and its role has been primarily to evaluate the possibility of intracerebral or subarachnoid hemorrhage. While conventional magnetic resonance (MR) imaging can demonstrate parenchymal abnormalities 4–6 hours after ischemia, newer techniques such as diff…