Silvia Minosse is a medical physicist working in diagnostic imaging at Policlinico Tor Vergata. Her research uses quantitative MRI, diffusion imaging and brain-network analysis to characterise tissue properties and evaluate imaging methods. She completed doctoral research in Medical Biotechnologies and Translational Medicine at Tor Vergata and has also worked on movement analysis and neurorehabilitation. Recent collaborations examine multimodal imaging in Parkinson's disease and dosimetric methods in brain-tumour research.
OBJECTIVE: To deepen the underlying pathophysiology of gait impairment in early-stage Parkinson's disease (PD) through a multimodal assessment, including MR-based brainstem morphometry and EEG functional connectivity (FC). METHODS: 73 PD patients and 60 healthy controls (HC) were included. The MR Parkinsonism Index (MRPI) was calculated for each subject. FC was measured using HD-EEG in θ-α-β-low-γ-high-γ bands. Partial Least Squares Path Modeling (PLS-PM) was used to explore the causal relationships between MRPI, FC, and clinical data. RESULTS: MRPI was higher in PD than HC (p = 0.001) and correlated with MDS-UPDRS-III gait subscore (r = 0.54,p < 0.001). α-FC was significantly lower in PD than HC (t = -5.4,p < 0.001). α-FC in PD was negatively correlated with both MRPI (r = -0.31,p = 0.007) and gait subscore (r = -0.31,p = 0.007). PLS-PM revealed MRPI's negative direct effect on α-FC (-0.59,p < 0.001) and significant positive total effect on gait performance (0.53,p < 0.001), partially mediated by α-FC (0.19, p = 0.006). Additionally, α-FC had a direct negative impact on gait performance (-0.33,p = 0.004). CONCLUSIONS: The effect of MRPI on gait performance, partially mediated by α-FC, highlights a dual pattern in which brainstem structural alterations show an association with gait impairment both directly and indirectly through their relationship with cortical functional disruptions. SIGNIFICANCE: These findings support a multimodal framework for understanding and addressing gait disorders in PD, potentially opening avenues for personalized treatment.
INTRODUCTION: This study aims to identify early brain network changes in de novo Parkinson's disease (PD) using resting state-functional Magnetic Resonance Imaging (rs-fMRI), graph-theoretical analysis, and a functional brain network disruption index (k), applied here for the first time to de novo PD. MATERIALS AND METHODS: The study enrolled untreated de novo PD patients and age- and sex-matched healthy controls. PD patients underwent comprehensive clinical assessments (MDS-UPDRS III, H&Y, MMSE, MoCA, NMSS). MRI data were acquired on a 3T system, including 3D T1-weighted MPRAGE and rs-fMRI. rs-fMRI data were pre-processed and analysed using graph theory. RESULTS: The study included 30 de novo PD patients and 30 healthy controls. While global network metrics did not differ significantly, local metrics revealed a reduced disruption index k in de novo PD patients. The disruption index k was negatively correlated with MMSE scores and demonstrated strong discriminatory power between PD patients and healthy controls based on clustering coefficient metrics. Significant differences in hub regions were found, as some disappeared in PD patients while others emerged compared to healthy controls. CONCLUSIONS: This study provides evidence of widespread functional alterations in the local brain networks of de novo Parkinson's disease (PD) patients, suggesting early reorganization of brain connectivity. The disruption index (k) demonstrated the ability to detect early and subtle changes in functional brain networks in de novo Parkinson patients. SIGNIFICANCE: rs-fMRI can provide valuable insights into the early stages of PD pathophysiology helping to understand the complexity of PD.
Conduct disorder (CD) is the leading global cause of mental health burden in children and adolescents and has recently been hypothesized to be a neurodevelopmental disorder. Although prior research has identified neuroanatomical differences associated with CD, it remains unclear whether these differences reflect atypical brain development. Here, we investigated the difference between an individual's brain age and chronological age as a proxy for variations in brain maturation. Using a pretrained model, we estimated brain age from structural neuroimaging data obtained from 1,119 youth with CD and 1,183 typically developing controls across 14 international cohorts participating in the ENIGMA-Antisocial Behavior Working Group. Youth with CD exhibited a statistically robust but small acceleration in brain age compared to typically developing youth (around 0.50 years), which was restricted to the adolescence-onset subtype of the disorder. Our large-scale, coordinated analysis provides the first evidence of accelerated neurodevelopment as a potential mechanism underlying CD.
BACKGROUND: Statins appear to be useful in patients with acute ischemic stroke. Our aim was to evaluate the association between premorbid statin treatment and CT perfusion characteristics of acute ischemic stroke. METHODS: A retrospective analysis of patients with acute stroke secondary to occlusion of large vessels in the anterior circulation was performed to assess collateral flow, ischemic core volume, and ischemic penumbra using CT angiography and CT perfusion maps. Fisher's exact test was used to compare baseline characteristics of patients in the two groups. The Wilcoxon rank-sum test for independent groups was used to compare all variables obtained for the two different groups with and without statin use. RESULTS: We identified 61 patients, including 29 treated with statins and 32 not treated with statins before stroke onset matched by age, gender, and vascular risk factors except for hypercholesterolemia. The statin group showed lower National Institutes of health Stroke Scale scores at onset (14 ± 6.1 vs. 16 ± 4.5; p = 0.04) and lower volumes of brain tissue characterized by impaired cerebral blood flow (CBF), cerebral blood volume (CBV), and Tmax9.5-25s; otherwise, no statistically significant difference was found in the volume of the Tmax16-25s between the two groups. CONCLUSIONS: Premorbid statin treatment is associated with a favorable imaging condition of acute ischemic stroke in terms of ischemic core and ischemic penumbra volume.
Background/Objectives: Parkinson's disease (PD) is characterized by progressive neurodegeneration affecting both motor and non-motor functions. Identifying early alterations in PD patients before the onset of dopaminergic therapy is crucial for understanding disease progression and developing targeted interventions. This study aimed to investigate early changes in the putamen and thalamus in de novo PD patients using diffusion tensor imaging (DTI) compared to healthy controls. Methods: Thirty-one de novo PD patients and thirty-three healthy controls underwent DTI scanning. Tract-based spatial statistics were used to compare fractional anisotropy (FA) values between groups. Results: De novo PD patients exhibited significantly lower FA values in the right thalamus compared to controls, suggesting alterations in neuronal integrity or fiber degeneration in the early stages of the disease. However, no significant differences were demonstrated for FA values in the putamen between groups. Conclusions: We demonstrated that the FA value in the right thalamus was lower in PD compared with healthy controls. These findings highlight the potential of DTI as a non-invasive tool for detecting early neural changes in PD patients. Further studies would be helpful to assess the clinical utility of serial FA measurements of the subcortical gray matter in objective quantification of disease progression and monitoring of the therapeutic response.