Search results for " neuroradiologia"

COMPARATIVE EVALUATION OF DATA PREPROCESSING SOFTWARE TOOLS TO INCREASE EFFICIENCY AND ACCURACY IN DIFFUSION KURTOSIS IMAGING

2016

Introduction: Diffusion tensor imaging (DTI) is the most commonly used technique to extract microstructural features from a set of diffusionweighted images. In addition to the metrics obtained with DTI, diffusion kurtosis imaging (DKI) can provide non-Gaussian diffusion measures by means of the kurtosis tensor. DKI has shown to be more sensitive to tissue microstructural changes in both normal and pathological neural tissue. In a clinical setting, however, these benefits are often nullified by numerous acquisition artifacts. The aim of this study was compare two preprocessing software for DTI apply to DKI. Also, the major preprocessing, processing and post-processing procedures applied to D…

Diffusion Kurtosis Imaging: prime applicazioni cliniche in ambito neuroradiologico

2014

Physics, Techniques and Review of Neuroradiological Applications of Diffusion Kurtosis Imaging (DKI)

2016

In recent years many papers about diagnostic applications of diffusion tensor imaging (DTI) have been published. This is because DTI allows to evaluate in vivo and in a non-invasive way the process of diffusion of water molecules in biological tissues. However, the simplified description of the diffusion process assumed in DTI does not permit to completely map the complex underlying cellular components and structures, which hinder and restrict the diffusion of water molecules. These limitations can be partially overcome by means of diffusion kurtosis imaging (DKI). The aim of this paper is the description of the theory of DKI, a new topic of growing interest in radiology. DKI is a higher or…

Hippocampal reversible lesions in a case of transient global amnesia

2018

We report the case of 55-year-old man that after an emotional stress showed retrograde and anterograde amnesia with impairment of orientation in space and time but undisturbed consciousness. A neurological examination excluded other neurological signs or symptoms. The amnesic syndrome resolved spontaneously within 24 hours and the hypothesis of transient global amnesia was placed. Brain CT scan and conventional MRI sequences did not show any relevant pathological findings but diffusion-weighted imaging (DWI) showed two millimetric bright spot of restricted diffusion in the right hippocampus; in a brain MRI follow-up those findings were no more appreciable. The diagnosis of transient global …

EMANGIOPERICITOMA INTRACRANICO PRESENTAZIONE DI UN CASO E REVISIONE DELLA LETTERATURA

2013

SCOPO DEL LAVORO Presentiamo a un caso di emangiopericitoma (HPC) in un paziente emicranico (maschio, 49 enne) che giunge alla nostra attenzione per l’insorgenza di confusione mentale e emisindrome sentitivo-motoria destra. Saranno inoltre riportati alcuni cenni sulla classificazione internazionale di questo raro tumore mesenchimale riccamente vascolarizzato, non tralasciando le possibili diagnosi differenziali con altri più comuni espansi di pertinenza extra- assiale. MATERIALI E METODI Dopo una prima valutazione in PS il paziente è stato sottoposto a esame TC encefalo e trasferito nel reparto di neurochirurgia. Successivamente ad un esame RM encefalo con sequenze morfologiche convenzion…

TRANS-CRANIAL MRI-GUIDED FOCUSED ULTRASOUND SURGERY (TCMRGFUS): ITALIAN AND WORLD-FIRST EXPERIENCE AT 1.5 TESLA

2016

Introduction: Transcranial magnetic resonance-guided focused ultrasound surgery (tcMRgFUS) is a promising new technology for the noninvasive treatment of various brain disorders. Here, we present our preliminary results achieved with the first Italian installation of a transcranial MRI-guided focused ultrasound surgery (tcMRgFUS) certified system for functional neurosurgery. Technical issues faced to achieve a safe and effective treatment will be discussed focusing on MR high-resolution live imaging and thermometry sequences optimization. Materials and Methods: Patient enrollment was based on indication for functional neurosurgery and evidence of medication-refractory disease; a detailed me…

MALATTIA DI ERDHEIM–CHESTER: RARE LOCALIZZAZIONI SPLANCNO- ED INTRA-CRANICHE IN PAZIENTE CON STADIO AVANZATO DI MALATTIA

2015

SCOPO DEL LAVORO Presentiamo il caso di una donna di 63 anni con storia di pseudotumor orbitae e diagnosi tardiva di Malattia di Erdheim-Chester (MEC) con coinvolgimento multisistemico e rare localizzazioni a livello splancno- ed intracranico. MATERIALI E METODI La paziente, a causa della comparsa di astenia progressivamente ingravescente, vomito e disfagia per i solidi veniva condotta al PS dove eseguiva ECG ed esami ematochimici e veniva ricoverata con la diagnosi di disidratazione e squilibrio elettrolitico. L’esame obiettivo evidenziava pallore e disidratazione di cute e mucose, ipotrofia muscolare e proptosi bulbare bilaterale da pseudotumor orbitario infiammatorio cronico con evidenti…

A 2D-FEM Model of Nonlinear Ultrasound Propagation in Trans-cranial MRgFUS Technique

2022

Magnetic Resonance guided Focused Ultrasound (MRgFUS) is a non-invasive technique based on the thermal ablation of a target using high intensity focused ultrasound. MRgFUS treatment applied to brain is challenging due to the skull presence that attenuates ultrasound, leading to heating effects in bone region. In this study, we simulate trans-cranial nonlinear ultrasound propagation considering the detailed structure of bone tissue. We developed a 2D Finite Element (FE) model that mimics the propagation of focused ultrasound through skin, skull and brain tissue. The skull is represented as a three-layered system with two cortical tables packing a layer of trabecular bone. We assume that the …

Neurochemical correlates of brain atrophy in fibromyalgia syndrome: a magnetic resonance spectroscopy and cortical thickness study

2020

(1) Background: Recently, a series of clinical neuroimaging studies on fibromyalgia (FM) have shown a reduction in cortical volume and abnormally high glutamate (Glu) and glutamate + glutamine (Glx) levels in regions associated with pain modulation. However, it remains unclear whether the volumetric decreases and increased Glu levels in FM are related each other. We hypothesized that higher Glu levels are related to decreases in cortical thickness (CT) and volume in FM patients. (2) Methods: Twelve females with FM and 12 matched healthy controls participated in a session of combined 3.0 Tesla structural magnetic resonance imaging (MRI) and single-voxel MR spectroscopy focused on the thalami…

Transcranial magnetic resonance imaging-guided focused ultrasound treatment at 1.5 T: a retrospective study on treatment and patient-related paramete…

2020

Objective: To present a retrospective analysis of patient- and sonication-related parameters of a group of patients treated with a transcranial magnetic resonance imaging (MRI)-guided focused ultrasound (tcMRgFUS) system integrated with a 1.5-T MRI unit. Methods: The data obtained from 59 patients, who underwent the tcMRgFUS procedure from January 2015 to April 2019, were retrospectively reviewed for this study. The following data, among others, were mainly collected: skull density ratio (SDR), skull area (SA), number of available transducer elements (Tx), and estimated focal power at target (FP). For each of the four different treatment stages, we calculated the number of sonication proces…