Search results for "MRI"

The effect of adult-acquired hippocampal damage on memory retrieval: an fMRI study.

2005

Bilateral hippocampal pathology typically results in significant memory problems. Despite apparently similar structural damage, patients with such lesions can differ in the pattern of impairment and preservation of memory functions. Previously, an fMRI study of a developmental amnesic patient whose anoxic hippocampal damage was incurred perinatally revealed his residual hippocampal tissue to be active during memory retrieval. This hippocampal activity was apparent during the retrieval of personal and general facts relative to a control task. In this study, we used a similar fMRI paradigm to investigate whether residual hippocampal activation was present also in patient VC with adult-acquire…

Introducing 1,5 T MRgFUS

2015

MRgFUS is a new noninvasive thermal ablation method, consisting of a high focused ultrasound beam and a MR scanner for imaging and real-time thermal mapping. For decades, therapeutic transcranial ultrasound (tcMRgFUS) was assumed impossible. Novel technology using high-power phased array transducers and multiple channel driving electronics enabled a sharp focal point in the planned target through the intact skull allowing the use of this innovative technology for functional neurosurgery. Preliminary results have been published with systems operating with 3T MR units on patients with neurologic disorders such as essential tremor, tremor dominant idiopathic Parkinson's disease and neuropathic…

Is there still a role for lesioning in functional neurosurgery: the Italian experience of delivering focused ultrasound high energy through a 1,5 tes…

2017

Tecnica, indicazioni e risultati trans-cranial MRgFUS

2015

Presentazione prima installazione nazionale di un apparecchiatura tcMRgFUS.

Benign focal lesions

2011

no abstract

DCE and DSC perfusion MRI acquisition: diagnostic accuracy during the follow-up of the primary and metastatic intra-axial brain tumors treated by Ste…

Distinguishing radiation necrosis from tumor recurrence and tumor progression is crucial for the evaluation of treatment response and treatment planning. The appearance of treatment-induced tissue necrosis on conventional Magnetic Resonance Imaging (MRI) are very similar to brain tumor recurrence and it could be difficult to differentiate the two entities during the follow-up MRI examinations. Dynamic Susceptibility Contrast-enhanced (DSC) and Dynamic Contrast-Enhanced (DCE) are the MRI perfusion techniques using an exogenous, intravascular, no diffusible gadolinium-based contrast agent. The aim of this study is to compare the diagnostic accuracy of DSC and DCE perfusion MRI in the differen…

MRI Characterization of non-Gaussian water diffusion in the brain using Diffusion Kurtosis Imaging (DKI)

2016

Diffusion tensor imaging (DTI) is the most commonly used technique to extract microstructural features from a set of diffusion-weighted 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 give an dimensionless measure that quantifies the deviation of the water diffusion displacement profile from the Gaussian distribution of unrestricted diffusion, providing a measure of the degree of diffusion hindrance or restriction. DKI has shown to be more sensitive to tissue microstructural changes in both normal and pathological neural tissue. The aim of this work is the description of t…

Functional connectivity modulation induced by transcranial direct current stimulation of the motor network: a Resting-State fMRI study

2016

Resting-state functional connectivity represents a novel fMRI approach that allows detection of temporal correlations in spontaneous BOLD signal oscillations while subjects rest quietly in the scanner. Functional connectivity (FC) can be defined as the synchrony of neural activity among spatially distant regions. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that is known to modulate cortical activity and FC among brain regions. This study is aimed at measuring the variation of functional connectivity between cortical brain regions after tDCS along time. The temporal concatenation group ICA showed that immediately after anodal stimulation the a…

IMAGING OF VESTIBULAR SCHWANNOMA [Chapter 4]

2020

Lesions of the cerebellopontine angle and internal auditory canal are a frequent finding in neuroradiological examinations and their detection may represent a diagnostic challenge. Among these lesions, vestibular schwannomas and meningiomas are certainly the most frequent and account for up to 90% of all cerebellopontine angle tumours. The remaining ones are a group of lesions arising from the different structures found in these anatomical regions such as haemangiomas, lipomas, lymphomas, facial nerve tumours, and aneurysms. This chapter will introduce this topic focusing on a practical coverage of the typical and atypical neuroradiological signs that will drive towards the most correct dif…

LESIONI REVERSIBILI DELL’IPPOCAMPO IN UN CASO DI AMNESIA GLOBALE TRANSITORIA

2013

SCOPO DEL LAVORO: Lo scopo di questo lavoro è documentare un caso di Amnesia Globale Transitoria (Transient Global Amnesia, TGA) in un paziente emicranico di sesso maschile di 52 anni con anamnesi negativa per epilessia, disturbi psichiatrici, traumi ed abusi di sostanze. Saranno inoltre effettuati dei cenni sull’epidemiologia e i meccanismi fisiopatologici oggi più accreditati nella letteratura scientifica più recente di questa controversa sindrome neurologica. MATERIALI E METODI: Poco dopo un forte stress emotivo il paziente non ricordava cosa avesse fatto durante il giorno e ripeteva incessantemente le stesse domande a cui erano comunque state date più volte delle risposte dai colleg…