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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 average value of voxels decreases significantly whereas there is no significant decrease in the case of sham tDCS stimulation. Our results show that anodal tDCS is able to induce connectivity changes within motor network, that is, reversible in a period lasting between 10′10′ and 20′20′ after stimulation.

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 the theory of DKI, the MRI protocol that we used for DKI acquisitions at 1.5T clinical scanner.

Introduction: Pseudotumoral-demyelinating lesions are typically characterized by severe difficulties in differential diagnosis from gliomas, metastatic tumors and abscesses. Marburg’s disease (MD) is an extremely rare and aggressive form of Mutiple Sclerosis (MS) with acute onset, rapid neurological deterioration, and poor prognosis. MRI images often show pseudotumoral lesions characterized by mild and focal or, sometimes, ring enhancement. Perhaps, radiological aspect can vary, making necessary hystopathological confirmation. Objectives: There is increasing interest in the role of surgical biopsy for a correct and early diagnosis of pseudotumoral demyelinating lesions. We report an histopathologically confirmed case of MD. Thanks to the analysis of actual literature, our purpose is to ameliorate diagnostic criteria, the timing of treatment and, subsequently, the prognosis of patients affected. Matherials and methods: A 24 years-old woman presented with a sudden onset of motor subaphasia and numbness to the right hemiface, followed, in a few hours by rapid deterioration with mild pyramidal right hemiparesis and complete aphasia. Patient underwent to a CT brain examination which showed three unspecific hypodense lesions: the bigger one, in the left subcortical frontal white matter, and two smaller lesions in the deep parietal and in the right paratrigonal white matter. For better characterization, a brain MRI was performed. The lesions in the right paratrigonal and left parietal white matter where appreciable as highly hyper-intense on TSE-T2 and FLAIR-T2 sequences, hypo-intense on TSE-T1, and responsible for a moderate mass effect on the surrounding structures; the left parietal white matter lesion also showed an incomplete and irregular ring-enhancement. The left subcortical frontal lesion was only mild hyper-intense on TSE-T2 and FLAIR-T2 but strongly hyper-intense on DWI, and a subsequent MRI scan showed a pseudotumoral development with an atypical patchy enhancement. Total body CT scan, auto-antibodies and viral serology on blood and CSF were negative. Isoelectric focusing in agarose gel detected the presence of CSF oligoclonal bands. Steroids were administrated without significant improvement. On the basis of the obtained data, and in consideration of the poor responsiveness to steroids, we performed a neuronavigator-aided biopsy of the main lesion through an open microsurgical approach. Preoperative planning was performed the day before by using contrast agent-enhanced brain CT scan, after positioning markers on the scalp. The exam was then transferred on a data storage device to insert CT images on the neuronavigator. The principal landmarks were used to realize a temporal craniotomy and a small corticectomy centred on the lesion. Finally, we detected, at a depth of about 2 cm, a pathological curdy and whitish tissue, ablated in small fragments and sent for hystological examination. A post-operative CT scan excluded any complications and the patient had a regular course. At demission, neurological exam was slightly better with partial regression of hemiparesis and partial amelioration of speech function. Hystopathological report confirmed the hypothesis of Marburg’s variant of MS. Results and Conclusions: Initial therapeutic approach to MS is pharmacological. However, in some atypical cases, CSF analisys, MRI images and/or clinical course after sterioids administration are not sufficiently diagnostic to completely rule out tumors or abscesses. So, early biopsy is an unavoidable necessity for the differential diagnosis of pseudotumoral-demyelinating lesions, to prevent inappropriate surgical or irradiative treatments and ameliorate the prognosis.

Rats self-administer acetaldehyde(ACD), ethanol's first metabolite, directly into cerebral ventricles (1), and multiple ICV infusions of ACD produce conditioned place preference (2). ACD, such as alcohol and other substances of abuse, interacts with dopaminergic reward system (3) and its reinforcing and addictive properties have been assessed through an operant-conflict conditioning procedure (4). Since dopamine D2receptor over-expression in the Nacc attenuates alcohol intake (5), this study aims at exploring the effects of ropinirole administration during abstinence, on ACD relapse. The protocol has been scheduled into 3 different periods: training ( animals have been trained to self-administer ACD solution 3,2%v/v in order to obtain the induction and maintenance of an operant-drinking behavior), deprivation ( rats have undergone repeated 1-week ACD abstinence during and received ropinirole at 0,03 mg/kg/day i.p.); and relapse (rats increase their operant behavior following deprivation). Our results indicate that ropinirole is able to reduce reinstatement of ACD operant-drinking behavior, confirming that hypo-dopaminergic activity is responsible for drug seeking behavior and relapse following abstinence. Further investigation could help considering ropinirole as a therapeutical tool for preventing alcohol drinking relapse. 1.Brown et al.(1979) Psychopharmacology 64:271-276. 2. Smith et al. (1984) Alcohol 1:193-195. 3. Melis M et al (2007)Eur J Neurosci. 26:2824-2833. 4.Cacace S et al., AlcoholClinExpRes 2012; 36(7):1278-87 5. Thanos et al. J Neurochem.2001;78:1094-1103.

Gli autori riportano un raro caso clinico di una paziente di 77 anni che giunge alla nostra osservazione in regime di urgenza per vertigine improvvisa associata a nausea e vomito, stato confusionale, atassia, paralisi completa del VI nervo cranico di destra con strabismo convergente, segni di sofferenza del IX, X ed XI nervo cranico omolaterali all’abducente e iniziale comparsa di segni statici e dinamici di paralisi periferica del VII nervo cranico di destra. L’insorgenza improvvisa di Sindromi paralitiche associate, anteriori e posteriori, ha indirizzato verso il sospetto di lesione occupante spazio a sede in fossa cranica posteriore/tronco encefalo richiedendo pertanto l’ausilio della diagnostica per immagini. Lo studio TC encefalo ha evidenziato la presenza di una formazione espansiva a densità similliquorale in fossa cranica posteriore, angolo ponto-cerebellare destro, nel cui contesto si è evidenziata area iperdensa da riferire a sanguinamento recente, con livello fluido-fluido, responsabile di importante effetto massa sulle strutture parenchimali contigue ed in particolare sulla sezione destra del tronco encefalo e dell’emisfero cerebellare omolaterale, con severa impronta sul IV ventricolo. L’assenza, alla valutazione della finestra per osso, di segni indiretti tipici da neurinoma stato acustico con interessamento del condotto uditivo interno (svasamento del porus e/o ampliamento del canale acustico interno) è risultata compatibile con la riferita negatività di pregressi segni clinici di pertinenza audio vestibolare. Lo studio RM encefalo eseguito tra le altre in tecnica 3D-FIESTA e 3D T1 FAT-SAT dopo MdC ev. ha permesso di identificare con certezza una lesione espansiva extra-assiale con componente tissutale solida che origina nel condotto uditivo interno da riferire a neurinoma. Nel contesto della componente extracanalare dello stesso, si riconosce un'unica ampia cavità cistica nel cui contesto si apprezza livello fluido-fluido per la presenza in sede declive di cataboliti dell’emoglobina come da sanguinamento recente intralesionale, verosimilmente responsabile del rapido aumento volumetrico della lesione stessa che giustificherebbe l’esordio clinico acuto con “Sindrome paralitica associata anteriore e posteriore”.