Sono una ricercatrice che lavora nelle Neuroscienze utilizzando gli strumenti delle neuroimmagini.
Studio la struttura e il funzionamento del cervello in soggetti sani e in pazienti con danno cerebrale.
La mia attività di ricerca riguarda lo studio delle funzioni cognitive, motorie e sensoriali nell’uomo per comprendere quali sono le aree che contribuiscono alle diverse funzioni, come queste sono organizzate e per comprendere i cambiamenti strutturali e funzionali che si verificano in presenza di malattie neurologiche.
Dal 2008 lavoro alla Fondazione IRCCS Istituto Neurologico C. Besta nel reparto di Neuroradiologia.
Rosazza, Andronache, Sattin [….] D’Incerti, Minati. Annals of Neurology (2016)
Objective: Understanding residual brain function in Disorders of Consciousness poses extraordinary challenges, and imaging examinations are needed to complement clinical assessment. The default-mode network (DMN) is known to be dysfunctional, although correlation with level of consciousness remains controversial. We investigated DMN activity with resting-state functional MRI (rs-fMRI), alongside its structural and metabolic integrity, aiming to elucidate the corresponding associations with clinical assessment.
Methods: We enrolled 119 consecutive patients: 72 vegetative state/unresponsive wakefulness state (VS/UWS), 36 minimally-conscious state (MCS) and 11 severe disability. All underwent structural MRI and rs-fMRI, and a subset also performed FDG-PET. Data were analyzed with manual and automatic approaches, in relation to diagnosis and clinical score.
Results: Excluding the quartile with largest head movement, DMN activity was decreased in VS/UWS compared to MCS, and correlated with clinical score. Independent-component and seed-based analyses provided similar results, though the latter and their combination were most informative. Structural MRI and FDG-PET were less sensitive to head movement and had superior diagnostic accuracy than rs-fMRI only when all cases were included. Rs-fMRI indicated relatively preserved DMN activity in a small subset of VS/UWS patients, two of whom evolved to MCS. The integrity of the left hemisphere appears predictive of a better clinical status.Interpretation: Rs-fMRI of the DMN is sensitive to clinical severity. The effect is consistent across data analysis approaches, but heavily dependent on head movement. Rs-fMRI could be informative to detect residual DMN activity for those patients that remain relatively still during scanning and whose diagnosis is uncertain. This article is protected by copyright. All rights reserved.
Rosazza, Sattin, Rossi Sebastiano, Minati, Leonardi. Neurology 2015
Commento su Neurology a un articolo uscito sulla stessa rivista che ha studiato con resting-state fMRI un gruppo di pazienti in coma.
Rosazza, Ghielmetti et al., NeuroImage Clinical, 2013
Studio fMRI del linguaggio nell’epilessia del lobo temporale (TLE). Lo studio ha preso in esame 72 pazienti con TLE, sottoposti a 3 compiti fMRI e a valutazione neuropsicologica pre- e post-operatoria. Si tratta di un’ampia casistica che ha permesso di dimostrare che la lateralizzazione fMRI del linguaggio può predire la performance postchirurgica.
In patients with temporal lobe epilepsy (TLE), assessment of language lateralization is important as anterior temporal lobectomy may lead to language impairments. Despite the widespread use of fMRI, evidence of its usefulness in predicting postsurgical language performance is scant.
We investigated whether preoperative functional lateralization is related to the preoperative language performance, peri-ictal aphasia, and can predict language outcome one year post-surgery.
We studied a total of 72 TLE patients (42 left, 30 right), by using three fMRI tasks: Naming, Verb Generation and Fluency. Functional lateralization indices were analyzed with neuropsychological scores and presence of peri-ictal aphasia.
The key findings are:
1) Both left and right TLE patients show decreased left lateralization compared to controls.
2) Lateralization correlates with language performance before surgery. In left TLE, decreased left lateralization correlates with better fluency performance. In right TLE, increased left lateralization during the Naming task correlates with better naming.
3) Left lateralization correlates with peri-ictal aphasia in left TLE patients.
4) Lateralization correlates with language performance after surgery. In a subgroup of left TLE who underwent surgery (17 left), decreased left lateralization is predictive of better naming performance at 6 and 12 months after surgery.
The present study highlights the clinical relevance of fMRI language lateralization in TLE, especially to predict language outcome one year post-surgery. We also underline the importance of using fMRI tasks eliciting frontal and anterior temporal activations, when studying left and right TLE patients.
Rosazza et al., PLoS One, 2014
Mappaggio preoperatorio della corteccia motoria attraverso due tecniche fMRI. Un gruppo di 13 pazienti con lesioni vicino alla corteccia motoria è stato sottoposto alla tradizionale tecnica di fMRI con task attivo e a resting-state fMRI per localizzare le aree motorie della mano, del piede e della bocca. Un confronto tra le due tecniche ha mostrato che la localizzazione tra le due tecniche non è equivalente, sebbene la tecnica di resting-state fMRI può essere considerata come alternativa quando i pazienti non sono in grado di svolgere il compito.
Resting state fMRI (rs-fMRI) has recently been considered as a possible complement or alternative to task-based fMRI (tb-fMRI) for presurgical mapping. However, evidence of its usefulness remains scant, because existing studies have investigated relatively small samples and focused primarily on qualitative evaluation. The aim of this study is to investigate the clinical usefulness of rs-fMRI in the context of presurgical mapping of motor functions, and in particular to determine the degree of correspondence with tb-fMRI which, while not a gold-standard, is commonly used in preoperative setting. A group of 13 patients with lesions close to the sensorimotor cortex underwent rs-fMRI and tb-fMRI to localize the hand, foot and mouth motor areas. We assessed quantitatively the degree of correspondence between multiple rs-fMRI analyses (independent-component and seed-based analyses) and tb-fMRI, with reference to sensitivity and specificity of rs-fMRI with respect to tb-fMRI, and centre-of-mass distances.
Agreement with electro-cortical stimulation (ECS) was also investigated, and a traditional map thresholding approach based on agreement between two experienced operators was compared to an automatic threshold determination method. Rs-fMRI can localize the sensorimotor cortex successfully, providing anatomical specificity for hand, foot and mouth motor subregions, in particular with seed-based analyses. Agreement with tb-fMRI was only partial and rs-fMRI tended to provide larger patterns of correlated activity. With respect to the ECS data available, rs-fMRI and tb-fMRI performed comparably, even though the shortest distance to stimulation points was observed for the latter. Notably, the results of both were on the whole robust to thresholding procedure. Localization performed by rs-fMRI is not equivalent to tb-fMRI, hence rs-fMRI cannot be considered as an outright replacement for tb-fMRI. Nevertheless, since there is significant agreement between the two techniques, rs-fMRI can be considered with caution as a potential alternative to tb-fMRI when patients are unable to perform the task.