Studio e sviluppo di un metodo di detezione della camera atriale in ecografia intracardiaca

Il lavoro di tesi si è svolto in collaborazione con il laboratorio di elettrofisiologia, Unità Operativa di Cardiologia, Dipartimento Cardiovascolare, dell’ospedale “S. Maria delle Croci” di Ravenna, Azienda Unità Sanitaria Locale della Romagna, ed ha come obiettivo lo sviluppo di un metodo per l’individuazione dell’atrio sinistro in sequenze di immagini ecografiche intracardiache acquisite durante procedure di ablazione cardiaca transcatetere per il trattamento della fibrillazione atriale. La localizzazione della parete posteriore dell'atrio sinistro in immagini ecocardiografiche intracardiache risulta fondamentale qualora si voglia monitorare la posizione dell'esofago rispetto alla parete stessa per ridurre il rischio di formazione della fistola atrio esofagea. Le immagini derivanti da ecografia intracardiaca sono state acquisite durante la procedura di ablazione cardiaca ed esportate direttamente dall’ecografo in formato Audio Video Interleave (AVI). L’estrazione dei singoli frames è stata eseguita implementando un apposito programma in Matlab, ottenendo così il set di dati su cui implementare il metodo di individuazione della parete atriale. A causa dell’eccessivo rumore presente in alcuni set di dati all’interno della camera atriale, sono stati sviluppati due differenti metodi per il tracciamento automatico del contorno della parete dell’atrio sinistro. Il primo, utilizzato per le immagini più “pulite”, si basa sull’utilizzo del modello Chan-Vese, un metodo di segmentazione level-set region-based, mentre il secondo, efficace in presenza di rumore, sfrutta il metodo di clustering K-means. Entrambi i metodi prevedono l’individuazione automatica dell’atrio, senza che il clinico fornisca informazioni in merito alla posizione dello stesso, e l’utilizzo di operatori morfologici per l’eliminazione di regioni spurie. I risultati così ottenuti sono stati valutati qualitativamente, sovrapponendo il contorno individuato all'immagine ecografica e valutando la bontà del tracciamento. Inoltre per due set di dati, segmentati con i due diversi metodi, è stata eseguita una valutazione quantitativa confrontatoli con il risultato del tracciamento manuale eseguito dal clinico

Managing Knowledge in the Era of Serious Games and Simulations: An exploratory study on the elicitation of serious games' requirements for the generation and reuse of knowledge

The extensive amount of knowledge possessed by an organization represents one of its most valuable resources. Nonetheless, it is not always easy to pinpoint, arrange and reuse such knowledge in an effective and productive manner. Moreover, in the last two decades companies have been increasingly using serious games and simulations for the most diverse scopes. While a consequent interest has been growing in the field of knowledge management regarding how to codify and reuse the information generated by these new innovative tools, there is still no clear understanding of what are the games' requirements which are responsible for the generation of knowledge. In addition to this, many theories can be identified in the available literature which developed methods and models for knowledge conversion and sharing; however, none of this models has yet been applied to the context of serious games and simulations. As a consequence of this recognized gap in the available literature, as well as of the need for organizations to develop a series of knowledge management systems and practices for the sharing and reusing of knowledge generate through games, this thesis research aims at understanding what are the necessary requirements for games to foster the development, as well as the reuse, of tacit knowledge.Primary scope of this thesis project has thus been to determine what games' elements represent a fundamental requirement for the generation of both explicit knowledge and tacit skills. In addition to this, the research has taken into consideration different groups of actors (game designers, participants/players, project team members, managers), and attempted to verify whether any dissimilarities exist among these groups in the way of perceiving games' requirements, and their impact on knowledge creation and sharing. Finally, in the light of the obtained results, suggestions have been proposed on the most appropriate knowledge management systems and procedure to use in the context of serious games and simulations. The research has been carried out in the form of an embedded, single-case study: the main unit of analysis - and client - was ProRail, the government organization which manages the maintenance and extensions of the national railway network infrastructure, the allocation of rail capacity, and the traffic control. The embedded units of analysis were instead represented by different games employed within the organization (OV-SAAL, Ketensimulatie, ERTMS). Once the games have been identified, other research methods have been applied within the case study framework, in particular: semi-structured interviews and Q-sorting. Concluding this dissertation report, recommendations for ProRail - the customer of this thesis project - have been outlined, by combining the obtained insights with theories from available literature. The scope has been to define suggestions for a knowledge management framework for serious games and simulations. The suggested framework, result of the joint efforts of different TU Delft researchers and ProRail's employees, is presented in the second-last chapter of this dissertation in the form of a set of recommendations for ProRail

Automatic Dynamic Quantification of Oesophagus Position from Intra:cardiac Echocardiography During Atrial Fibrillation Ablation

Left atrium posterior wall (LAPW) is an essential target for transcatheter radiofrequency ablation (RFA) of atrial fibrillation (AF), but poses problems due to retro-atrial structures potentially damaged by RF. Intracardiac echocardiography (ICE) can be integrated with the 3D electro-anatomical map and can give unique real-time anatomical information about all closely-located peri-cardiac structures. The present study aimed to automatically detect dynamic oesophagus position and its spatial relationship from the LAPW by ICE during RFA. A fast algorithm based on the evaluation of gray-level intensity distribution in the image and was developed to detect distal and proximal oesophagus boundaries. The algorithm was tested in 15 ICE acquisitions. The detected oesophagus boundaries and those manually traced (MT) were compared and in 5 ICE sequences, dynamic tracking of proximal oesophagus boundary was performed. Mean analysis time was 4.5 sec/frame. Detected oesophagus wall positions were in good agreement with MT. Mean minimum dynamic distance between LAPW and oesophagus proximal wall during acquisition was 0.3\ub10.2mm (range: 0.0-0.6mm). This technique allows automated and accurate dynamic detection of LAPW and oesophagus position in ICE sequences. It represents a first step for dynamic quantification of oesophagus real-time position\u2019 changes and its distance from the LAPW to prevent oesophagus injuries

Effectiveness of long-acting risperidone in a patient with comorbid intellectual disability, catatonic schizophrenia, and oneiroid syndrome

A patient with comorbid intellectual disability, catatonic schizophrenia, and recurrent oneiroid state of consciousness improved on long-acting risperidone and remains well at the three-year follow-up. We report a case treated with 50 mg long-acting risperidone administered every 14 days, who has been followed-up for three years. We studied his regional cerebral blood flow through technetium-99 m hexamethylpropyleneamine oxime single-photon emission computed tomography after two years of treatment. Symptoms of catatonic schizophrenia improved after two months of treatment, followed suit by oneiroid syndrome remission. Two years later, his brain perfusion was normal. No side effect has occurred since the patient was started on long-acting risperidone. Long-acting risperidone proved to be safe and effective in treating symptoms of catatonia and oneiroid syndrome

Add-on high frequency deep transcranial magnetic stimulation (dTMS) to bilateral prefrontal cortex reduces cocaine craving in patients with cocaine use disorder

Cocaine dependence is a substantial public health problem. The aim of this study is to evaluate the effect of high frequency deep transcranial magnetic stimulation (dTMS) on craving in patients with cocaine use disorder (CUD)

Add-on deep transcranial magnetic stimulation (dTMS) in patients with dysthymic disorder comorbid with alcohol use disorder. A comparison with standard treatment

Objectives. Dorsolateral prefrontal cortex (DLPFC) is dysfunctional in mood and substance use disorders. We predicted higher efficacy for add-on bilateral prefrontal high-frequency deep transcranial magnetic stimulation (dTMS), compared with standard drug treatment (SDT) in patients with dysthymic disorder (DD)/alcohol use disorder (AUD) comorbidity. Methods. We carried-out a 6-month open-label study involving 20 abstinent patients with DSM-IV-TR AUD comorbid with previously developed DD. Ten patients received SDT for AUD with add-on bilateral dTMS (dTMS-AO) over the DLPFC, while another 10 received SDT alone. We rated alcohol craving with the Obsessive Compulsive Drinking Scale (OCDS), depression with the Hamilton Depression Rating Scale (HDRS), clinical status with the Clinical Global Impressions scale (CGI), and global functioning with the Global Assessment of Functioning (GAF). Results. At the end of the 20-session dTMS period (or an equivalent period in the SDT group), craving scores and depressive symptoms in the dTMS-AO group dropped significantly more than in the SDT group (P < 0.001 and P < 0.02, respectively). Conclusions. High frequency bilateral DLPFC dTMS with left preference was well tolerated and found to be effective as add-on in AUD. The potential of dTMS for reducing craving in substance use disorder patients deserves to be further investigated

Antidepressant effectiveness of deep Transcranial Magnetic Stimulation (dTMS) in patients with Major Depressive Disorder (MDD) with or without Alcohol Use Disorders (AUDs): A 6-month, open label, follow-up study

INTRODUCTION: Co-occurrence of Major Depressive (MDD) and Alcohol Use Disorders (AUDs) is frequent, causing more burden than each disorder separately. Since the dorsolateral prefrontal cortex (DLPFC) is critically involved in both mood and reward and dysfunctional in both conditions, we aimed to evaluate the effects of dTMS stimulation of bilateral DLPFC with left prevalence in patients with MDD with or without concomitant AUD. METHODS: Twelve MDD patients and 11 with concomitant MDD and AUD (MDD+AUD) received 20 dTMS sessions. Clinical status was assessed through the Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impressions severity scale (CGIs), craving through the Obsessive Compulsive Drinking Scale (OCDS) in MDD+AUD, and functioning with the Global Assessment of Functioning (GAF). RESULTS: There were no significant differences between the two groups in sociodemographic (age, sex, years of education and duration of illness) and baseline clinical characteristics, including scores on assessment scales. Per cent drops on HDRS and CGIs scores at the end of the sessions were respectively 62.6% and 78.2% for MDD+AUD, and 55.2% and 67.1% for MDD (p<0.001). HDRS, CGIs and GAF scores remained significantly improved after the 6-month follow-up. HDRS scores dropped significantly earlier in MDD+AUD than in MDD LIMITATIONS: The small sample size and factors inherent to site and background treatment may have affected results. CONCLUSIONS: High frequency bilateral DLPFC dTMS with left preference was well tolerated and effective in patients with MDD, with or without AUD. The antidepressant effect of dTMS is not affected by alcohol abuse in patients with depressive episodes. The potential use of dTMS for mood modulation as an adjunct to treatment in patients with a depressive episode, with or without alcohol abuse, deserves further investigation