Emma Biondetti

University of Chieti-Pescara | UNICH · Department of Neuroscience Imaging and Clinical Sciences

Free water fraction (FWF) represents the amount of water per unit volume of brain parenchyma, which is not bound to macromolecules. Its excess in multiple sclerosis (MS) is related to increased tissue loss. The use of mcDESPOT (multicomponent driven single pulse observation of T1 and T2), a 3D imaging method which exploits both the T1 and T2 contra...

Neurovascular alterations are increasingly recognized as a key feature of many brain diseases. They can manifest as a reduction in resting cerebral blood flow or cerebrovascular reactivity (CVR) in the whole brain or in specific regions, depending on the underlying condition. Neurovascular impairment is observed in hypertension, Alzheimer’s disease...

Temporal lobe epilepsy (TLE) is associated with widespread brain alterations. Using quantitative susceptibility mapping (QSM) alongside transverse relaxation rate ( R 2 * $$ {R}_2^{\ast } $$ ), we investigated regional brain susceptibility changes in 36 patients with left-sided (LTLE) or right-sided TLE (RTLE) secondary to hippocampal sclerosis, an...

Background: Reduced cerebral perfusion has been observed in Multiple Sclerosis and may contribute to tissue loss both acutely and chronically. Here, we test the hypothesis that hypoperfusion occurs in MS and relates to the presence of irreversible tissue damage. Methods: In 91 patients with relapsing MS and 26 healthy controls (HC), GM CBF was a...

This article provides an overview of MRI methods exploiting magnetic susceptibility properties of blood to assess cerebral oxygen metabolism, including the tissue oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2). The first section is devoted to describing blood magnetic susceptibility and its effect on the MRI sign...

Myelin is the protective sheath wrapped around axons, consisting of a phospholipid bilayer with water between the wraps. The measurement of damage to the myelin sheaths, the evaluation of the efficacy of therapies aiming to promote remyelination as well as monitoring the degree of brain maturation in children require non-invasive quantitative myeli...

Cerebrovascular reactivity (CVR) reflects the capacity of the brain’s vasculature to increase blood flow following a vasodilatory stimulus. Reactivity is an essential property of the brain’s blood vessels that maintains nutrient supplies in the face of changing demand. In Multiple Sclerosis (MS), CVR may be diminished with brain inflammation and th...

Purpose To compare different multi‐echo combination methods for MRI QSM. Given the current lack of consensus, we aimed to elucidate how to optimally combine multi‐echo gradient‐recalled echo signal phase information, either before or after applying Laplacian‐base methods (LBMs) for phase unwrapping or background field removal. Methods Multi‐echo g...

Background: Neurodegeneration in the substantia nigra pars compacta (SNc) in parkinsonian syndromes may affect the nigral territories differently. Objective: The objective of this study was to investigate the regional selectivity of neurodegenerative changes in the SNc in patients with Parkinson's disease (PD) and atypical parkinsonism using neu...

One promising approach for mapping CMRO2 is dual-calibrated functional MRI (dc-fMRI). This method exploits the Fick Principle to combine estimates of CBF from ASL, and OEF derived from BOLD-ASL measurements during arterial O2 and CO2 modulations. Multiple gas modulations are required to decouple OEF and deoxyhemoglobin-sensitive blood volume. We pr...

Background: Isolated REM sleep behavior disorder (iRBD) is considered a prodromal stage of parkinsonism. Neurodegenerative changes in the substantia nigra pars compacta (SNc) in parkinsonism can be detected using neuromelanin-sensitive MRI. Objective: To investigate SNc neuromelanin changes in iRBD patients using fully automatic segmentation. M...

On behalf of the International Society for Magnetic Resonance in Medicine (ISMRM) Quantitative MR Study Group, this article provides an overview of considerations for the development, validation, qualification, and dissemination of quantitative MR (qMR) methods. This process is framed in terms of two central technical performance properties, i.e.,...

Quantitative susceptibility mapping (QSM) is a promising non-invasive method for obtaining information relating to the oxygen metabolism. However, the optimal acquisition sequence and QSM reconstruction method for reliable venous susceptibility measurements are unknown. Full flow compensation is generally recommended to correct for the influence of...

Purpose: To compare different multi-echo combination methods for MRI quantitative susceptibility mapping (QSM), aiming to elucidate, given the current lack of consensus, how to optimally combine multi-echo gradient-recalled echo (GRE) signal phase information, either before or after applying Laplacian-base methods (LBMs) for phase unwrapping or bac...

In Parkinson’s disease, there is a progressive reduction in striatal dopaminergic function, and loss of neuromelanin-containing dopaminergic neurons and increased iron deposition in the substantia nigra. We tested the hypothesis of a relationship between impairment of the dopaminergic system and changes in the iron metabolism. Based on imaging data...

Quantitative susceptibility mapping (QSM) is a promising non-invasive method for obtaining information relating to the oxygen metabolism. However, the optimal acquisition sequence and QSM reconstruction method for reliable venous susceptibility measurements are unknown. Full flow compensation is generally recommended to correct for the influence of...

Background: Development of reliable and accurate imaging biomarkers of dopaminergic cell neurodegeneration is necessary to facilitate therapeutic drug trials in Parkinson's disease (PD). Neuromelanin-sensitive MRI techniques have been effective in detecting neurodegeneration in the substantia nigra pars compacta (SNpc). The objective of the curren...

Purpose: Intra-arterial Digital Subtraction Angiography (DSA) is the gold standard technique for radiosurgery target delineation in brain Arterio-Venous Malformations (AVMs). This study aims to evaluate whether a combination of three Magnetic Resonance Angiography sequences (triple-MRA) could be used for delineation of brain AVMs for Gamma Knife R...

Background Machine learning algorithms using magnetic resonance imaging (MRI) data can accurately discriminate parkinsonian syndromes. Validation in patients recruited in routine clinical practice is missing. Objective The aim of this study was to assess the accuracy of a machine learning algorithm trained on a research cohort and tested on an ind...

This study aimed to investigate the spatiotemporal changes in neuromelanin-sensitive MRI signal in the substantia nigra and their relation to clinical scores of disease severity in patients with early or progressing Parkinson's disease and patients with idiopathic rapid eye movement sleep behaviour disorder (iRBD) exempt of Parkinsonian signs compa...

Purpose Multi‐echo gradient‐recalled echo acquisitions for QSM enable optimizing the SNR for several tissue types through multi‐echo (TE) combination or investigating temporal variations in the susceptibility (potentially reflecting tissue microstructure) by calculating one QSM image at each TE (TE‐dependent QSM). In contrast with multi‐echo QSM, a...

Background: Several studies have shown that machine learning algorithms using MRI data can accurately discriminate parkinsonian syndromes. Validation under clinical conditions is missing. Objectives: To evaluate the accuracy for the categorization of parkinsonian syndromes of a machine learning algorithm trained with a research cohort and tested on...

Objectifs Le diagnostic différentiel des syndromes parkinsoniens d’origine neurodégénérative est difficile, notamment en phase précoce. L’IRM structurelle constitue une aide diagnostique précieuse puisqu’elle fournit des biomarqueurs capables de discriminer les différentes entités. Alors que l’imagerie est considérée normale dans la maladie de Park...

Brain arteriovenous malformations (AVMs) are congenital vascular anomalies characterized by arteriovenous shunting through a network of coiled and tortuous vessels. Because of this anatomy, the venous drainage of an AVM is hypothesized to contain more oxygenated, arterialized blood than healthy veins. By exploiting the paramagnetic properties of de...

Magnetic resonance imaging (MRI) magnetic susceptibility mapping (SM) enables the calculation of the magnetic susceptibility of biological tissues based on the signal phase of a gradient-recalled echo (GRE) MRI acquisition. Because deoxygenated haemoglobin is paramagnetic, SM can be used to calculate the χ of venous blood which is proportional to v...

For Susceptibility Mapping (SM), Laplacian-based methods (LBMs) can be used on single- or multi-echo gradient echo phase data. Previous studies have shown the advantage of using multi-echo versus single-echo data for noise reduction in susceptibility-weighted images and simulated data. Here, using simulated and acquired images, we compared the perf...

This study investigates whether a combination of three MRA techniques, referred to as triple-MRA, could be used as an alternative to DSA for visualisation and delineation of brain AVMs for GKR targeting. The AVMs of 13 patients undergoing GKR were delineated using triple-MRA and the resultant target volumes were compared to the radiosurgical target...

Brain arteriovenous malformations (AVMs) are vascular abnormalities characterised by arteriovenous shunting with the lack of a capillary bed. Recent studies have shown that it is possible to create diagrams of the cerebral vein network (venograms) from images of magnetic susceptibility. Here, we used susceptibility-based venograms to calculate the...

In Susceptibility Mapping (SM) using multi-echo gradient-echo phase data, unwrapping and/or background-field removal is often performed using Laplacian based methods. However, SM pipelines in the literature have applied these methods at different stages. Here, using simulated and acquired images, we compared the performance of three pipelines that...

Susceptibility Mapping has emerging clinical applications. To reduce scan time, clinical images are often acquired with large slice spacing/thickness and reduced coverage. The effect of these factors on susceptibility maps has not been investigated. Here, we develop a simple framework to explore the effect of low-resolution and low-coverage in the...