From paper to informatics: the Post Soft Care-App, an easy-to-use and fast tool to help therapists identify unmet needs in stroke patients.

Even after rehabilitation, post stroke patients remain disabled. The Post Stroke Checklist (PSC) was developed to highlight unmet needs of community-dwelling stroke patients. The present study set out to validate Post Soft Care-App, designed to administer the PSC using smartphones and tablets, in order to monitor unmet needs in chronic patients. Fifty-three patients and fifteen physiotherapists were enrolled. The therapists administered the PSC to patients using the app, and then completed a structured questionnaire on its usability and utility. The Post Soft Care-App highlighted the following unmet needs: increased spasticity (56.6%), reduced independence in activities of daily living (47.2%), reduced mobility (45.3%), absence of secondary prevention (45.3%). Therapists positively evaluated Post Soft Care-App as useful, practical, quick to complete (96.2%), and effective in helping improve communication with patients (75.5%). The Post Soft Care-App can be considered a valid assessment tool for helping therapists to monitor functional outcomes in chronic patients.

Influence of P300 latency jitter on event related potential-based brain-computer interface performance.

OBJECTIVE: Several ERP-based brain-computer interfaces (BCIs) that can be controlled even without eye movements (covert attention) have been recently proposed. However, when compared to similar systems based on overt attention, they displayed significantly lower accuracy. In the current interpretation, this is ascribed to the absence of the contribution of short-latency visual evoked potentials (VEPs) in the tasks performed in the covert attention modality. This study aims to investigate if this decrement (i) is fully explained by the lack of VEP contribution to the classification accuracy; (ii) correlates with lower temporal stability of the single-trial P300 potentials elicited in the covert attention modality. APPROACH: We evaluated the latency jitter of P300 evoked potentials in three BCI interfaces exploiting either overt or covert attention modalities in 20 healthy subjects. The effect of attention modality on the P300 jitter, and the relative contribution of VEPs and P300 jitter to the classification accuracy have been analyzed. MAIN RESULTS: The P300 jitter is higher when the BCI is controlled in covert attention. Classification accuracy negatively correlates with jitter. Even disregarding short-latency VEPs, overt-attention BCI yields better accuracy than covert. When the latency jitter is compensated offline, the difference between accuracies is not significant. SIGNIFICANCE: The lower temporal stability of the P300 evoked potential generated during the tasks performed in covert attention modality should be regarded as the main contributing explanation of lower accuracy of covert-attention ERP-based BCIs.

Self-calibration algorithm in an asynchronous P300-based brain-computer interface.

OBJECTIVE: Reliability is a desirable characteristic of brain-computer interface (BCI) systems when they are intended to be used under non-experimental operating conditions. In addition, their overall usability is influenced by the complex and frequent procedures that are required for configuration and calibration. Earlier studies examined the issue of asynchronous control in P300-based BCIs, introducing dynamic stopping and automatic control suspension features. This report proposes and evaluates an algorithm for the automatic recalibration of the classifier's parameters using unsupervised data. APPROACH: Ten healthy subjects participated in five P300-based BCI sessions throughout a single day. First, we examined whether continuous adaptation of control parameters improved the accuracy of the asynchronous system over time. Then, we assessed the performance of the self-calibration algorithm with respect to the no-recalibration and supervised calibration conditions with regard to system accuracy and communication efficiency. MAIN RESULTS: Offline tests demonstrated that continuous adaptation of the control parameters significantly increased the communication efficiency of asynchronous P300-based BCIs. The self-calibration algorithm correctly assigned labels to unsupervised data with 95% accuracy, effecting communication efficiency that was comparable with that of supervised repeated calibration. SIGNIFICANCE: Although additional online tests that involve end-users under non-experimental conditions are needed, these preliminary results are encouraging, from which we conclude that the self-calibration algorithm is a promising solution to improve P300-based BCI usability and reliability.

A comparison of classification techniques for a gaze-independent P300-based brain-computer interface.

This off-line study aims to assess the performance of five classifiers commonly used in the brain-computer interface (BCI) community, when applied to a gaze-independent P300-based BCI. In particular, we compared the results of four linear classifiers and one nonlinear: Fisher's linear discriminant analysis (LDA), stepwise linear discriminant analysis (SWLDA), Bayesian linear discriminant analysis (BLDA), linear support vector machine (LSVM) and Gaussian supported vector machine (GSVM). Moreover, different values for the decimation of the training dataset were tested. The results were evaluated both in terms of accuracy and written symbol rate with the data of 19 healthy subjects. No significant differences among the considered classifiers were found. The optimal decimation factor spanned a range from 3 to 24 (12 to 94 ms long bins). Nevertheless, performance on individually optimized classification parameters is not significantly different from a classification with general parameters (i.e. using an LDA classifier, about 48 ms long bins).

EEG-based Brain-Computer Interface to support post-stroke motor rehabilitation of the upper limb.

Brain-Computer Interfaces (BCIs) process brain activity in real time, and mediate non-muscular interaction between and individual and the environment. The subserving algorithms can be used to provide a quantitative measurement of physiological or pathological cognitive processes - such as Motor Imagery (MI) - and feed it back the user. In this paper we propose the clinical application of a BCI-based rehabilitation device, to promote motor recovery after stroke. The BCI-based device and the therapy exploiting its use follow the same principles that drive classical neuromotor rehabilitation, and (i) provides the physical therapist with a monitoring instrument, to assess the patient's participation in the rehabilitative cognitive exercise; (ii) assists the patient in the practice of MI. The device was installed in the ward of a rehabilitation hospital and a group of 29 patients were involved in its testing. Among them, eight have already undergone a one-month training with the device, as an add-on to the regular therapy. An improved system, which includes analysis of Electromyographic (EMG) patterns and Functional Electrical Stimulation (FES) of the arm muscles, is also under clinical evaluation. We found that the rehabilitation exercise based on BCI-mediated neurofeedback mechanisms enables a better engagement of motor areas with respect to motor imagery alone and thus it can promote neuroplasticity in brain regions affected by a cerebrovascular accident. Preliminary results also suggest that the functional outcome of motor rehabilitation may be improved by the use of the proposed device.

Workload measurement in a communication application operated through a P300-based brain-computer interface.

Advancing the brain-computer interface (BCI) towards practical applications in technology-based assistive solutions for people with disabilities requires coping with problems of accessibility and usability to increase user acceptance and satisfaction. The main objective of this study was to introduce a usability-oriented approach in the assessment of BCI technology development by focusing on evaluation of the user's subjective workload and satisfaction. The secondary aim was to compare two applications for a P300-based BCI. Eight healthy subjects were asked to use an assistive technology solution which integrates the P300-based BCI with commercially available software under two conditions--visual stimuli needed to evoke the P300 response were either overlaid onto the application's graphical user interface or presented on a separate screen. The two conditions were compared for effectiveness (level of performance), efficiency (subjective workload measured by means of NASA-TXL) and satisfaction of the user. Although no significant difference in usability could be detected between the two conditions, the methodology proved to be an effective tool to highlight weaknesses in the technical solution.

P300-based brain-computer interface for environmental control: an asynchronous approach.

Brain-computer interface (BCI) systems allow people with severe motor disabilities to communicate and interact with the external world. The P300 potential is one of the most used control signals for EEG-based BCIs. Classic P300-based BCIs work in a synchronous mode; the synchronous control assumes that the user is constantly attending to the stimulation, and the number of stimulation sequences is fixed a priori. This issue is an obstacle for the use of these systems in everyday life; users will be engaged in a continuous control state, their distractions will cause misclassification and the speed of selection will not take into account users' current psychophysical condition. An efficient BCI system should be able to understand the user's intentions from the ongoing EEG instead. Also, it has to refrain from making a selection when the user is engaged in a different activity and it should increase or decrease its speed of selection depending on the current user's state. We addressed these issues by introducing an asynchronous BCI and tested its capabilities for effective environmental monitoring, involving 11 volunteers in three recording sessions. Results show that this BCI system can increase the bit rate during control periods while the system is proved to be very efficient in avoiding false negatives when the users are engaged in other tasks.

Neuropolitics: EEG spectral maps related to a political vote based on the first impression of the candidate's face.

The aim of the present research is to investigate the EEG activity elicited by a fast observation of face of real politicians during a simulated political election. Politician's face are taken from real local election performed in Italy in the 2004 and 2008. We recorded the EEG activity of eight healthy subjects while they are asked to give a judgment on dominance, trustworthiness traits and a preference of vote on faces shown. Statistical differences of spectral EEG scalp activity have been mapped onto a realistic head model. For each experimental condition, we employed the t-test to compare the PSD values and adopted the False Discovery Rate correction for multiple comparisons. The scalp statistical maps revealed a desynchronization in the alpha band related to the politicians who lost the simulated elections and have been judged less trustworthy. Although these results might be congruent with the recent literature, the present is the first EEG study about and there is the need to extend the paradigm and the analysis on a larger number of subjects to validate these results.

On the use of electrooculogram for efficient human computer interfaces.

The aim of this study is to present electrooculogram signals that can be used for human computer interface efficiently. Establishing an efficient alternative channel for communication without overt speech and hand movements is important to increase the quality of life for patients suffering from Amyotrophic Lateral Sclerosis or other illnesses that prevent correct limb and facial muscular responses. We have made several experiments to compare the P300-based BCI speller and EOG-based new system. A five-letter word can be written on average in 25 seconds and in 105 seconds with the EEG-based device. Giving message such as "clean-up" could be performed in 3 seconds with the new system. The new system is more efficient than P300-based BCI system in terms of accuracy, speed, applicability, and cost efficiency. Using EOG signals, it is possible to improve the communication abilities of those patients who can move their eyes.

A hybrid platform based on EOG and EEG signals to restore communication for patients afflicted with progressive motor neuron diseases.

An efficient alternative channel for communication without overt speech and hand movements is important to increase the quality of life for patients suffering from Amiotrophic Lateral Sclerosis or other illnesses that prevent correct limb and facial muscular responses. Often, such diseases leave the ocular movements preserved for a relatively long time. The aim of this study is to present a new approach for the hybrid system which is based on the recognition of electrooculogram (EOG) and electroencephalogram (EEG) measurements for efficient communication and control. As a first step we show that the EOG-based side of the system for communication and controls is useful for patients. The EOG side of the system has been equipped with an interface including a speller to notify of messages. A comparison of the performance of the EOG-based system has been made with a BCI system that uses P300 waveforms. As a next step, we plan to integrate EOG and EEG sides. The final goal of the project is to realize a unique noninvasive device able to offer the patient the partial restoration of communication and control abilities with EOG and EEG signals.

On the use of brain-computer interfaces outside scientific laboratories toward an application in domotic environments.

Brain-computer interface (BCI) applications were initially designed to provide final users with special capabilities, like writing letters on a screen, to communicate with others without muscular effort. In these last few years, the BCI scientific community has been interested in bringing BCI applications outside the scientific laboratories, initially to provide useful applications in everyday life and in future in more complex environments, such as space. Recently, we implemented a control of a domestic environment realized with BCI applications. In the present chapter, we analyze the methodological approach employed to allow the interaction between subjects and domestic devices by use of noninvasive EEG recordings. In particular, we analyze whether the cortical activity estimated from noninvasive EEG recordings could be useful in detecting mental states related to imagined limb movements. We estimate cortical activity from high-resolution EEG recordings in a group of healthy subjects by using realistic head models. Such cortical activity was estimated in a region of interest associated with the subjects' Brodmann areas by use of depth-weighted minimum norm solutions. Results show that the use of the estimated cortical activity instead of unprocessed EEG improves the recognition of the mental states associated with limb-movement imagination in a group of healthy subjects. The BCI methodology here presented has been used in a group of disabled patients to give them suitable control of several electronic devices disposed in a three-room environment devoted to neurorehabilitation. Four of six patients were able to control several electronic devices in the domotic context with the BCI system, with a percentage of correct responses averaging over 63%.

The estimation of cortical activity for brain-computer interface: applications in a domotic context.

In order to analyze whether the use of the cortical activity, estimated from noninvasive EEG recordings, could be useful to detect mental states related to the imagination of limb movements, we estimate cortical activity from high-resolution EEG recordings in a group of healthy subjects by using realistic head models. Such cortical activity was estimated in region of interest associated with the subject's Brodmann areas by using a depth-weighted minimum norm technique. Results showed that the use of the cortical-estimated activity instead of the unprocessed EEG improves the recognition of the mental states associated to the limb movement imagination in the group of normal subjects. The BCI methodology presented here has been used in a group of disabled patients in order to give them a suitable control of several electronic devices disposed in a three-room environment devoted to the neurorehabilitation. Four of six patients were able to control several electronic devices in this domotic context with the BCI system.

[Liver haemangioma: current surgical indications. Our experience]. / Gli angiomi epatici: attuali indicazioni al trattamento chirurgico. Revisione casistica.

Hemangiomas are the more frequent benign liver tumours. Therapeutic approach at these neoplasms is changed in the last years because has resulted that massive haemoperitoneum from a spontaneous rupture of the hemangiomas is a rare occurrence. From a personal review of 124 liver resection performed for traumatic and organic, benign and malignant, pathologies, the Authors present two cases of symptomatic liver haemangioma surgically treated Excluding emergency induced by tumour hemorrhage, actually indications to surgical treatment are controversial. In all patients the right approach is choice by the integrated evaluation of general conditions of the patient, liver functionality and from anatomical location of the neoplasm.

[Appendicectomy: laparoscopic versus open treatment. A case survey]. / Appendicectomia: laparoscopica versus laparotomica. Analisi della casistica.

AIM: Laparoscopy is actually the gold standard approach in many surgical procedures: this consideration is still controversial as to appendectomy. METHODS: From 2000 to 2004 we have performed 257 appendectomies: 51 (20%) in laparoscopic approach. Preoperative diagnosis has been formulated on blood parameters, abdominal or, sometimes, transvaginal ultrasonography. RESULTS: Two hundred and fifty-seven surgical operations, 62 laparoscopic, have been performed for suspicious appendicitis. In the laparoscopic procedures, 11 revealed various diseases without appendicitis. In the remaining 51 cases, appendectomy has been performed totally intra-abdominal and none case turned to laparotomic conversion. Operative times were between 27 and 105 min in the laparoscopic appendectomies (LA) and between 18 and 46 min in the laparotomic appendectomies (OA). In 7.3% of OA and in 3.9% of LA wall infections occurred, as well as abdominal abscesses in 1% of OA and in 4% of LA. Postoperative discharge was after 3.3 days and bowel canalization appeared at 10-18 hours from the surgery, in OA and in LA. CONCLUSIONS: On the basis of these results, the conclusion is drawn that, although discordant opinions in the literature, the advantages of the laparoscopic approach compared to laparotomic approach is still to be demonstrated, both in advantages for the patient and in costs. Laparoscopy is the better surgical technique when the preoperative diagnosis is not clear, particularly in young women or in elderly, in whom a colic neoplasm may be suspected.

[Management of the neoplastic stenosis of the left colon with self-expandable endoprosthesis]. / Il trattamento delle stenosi neoplastiche del colon sinistro mediante endoprotesi autoespandibili.

Malignant tumors of the large bowel develop colonic obstruction in 10-30% cases. Recently many authors have employed self-expandable stents to resolve the colonic obstruction. During 2002, seven patients affected by neoplastic malignant stenosis of the left colon underwent endoscopic placement of self-expandable enteral stent. The technique succeeded in relieving the obstruction in 6 patients, while in a woman affected by malignant tumor of the splenic flexure, colonic stenting was unsuccessful. The Authors didn't observe any procedure related complications; sign and symptoms of intestinal obstruction resolved within 24-72 hours from placement. Four patients needed hydro-electrolitemic correction, intestinal cleaning and R0 resection with one stage anastomosis within 5 and 9 days. Bowel decompression of the neoplastic stenosis relieved by self expandable metallic stents is useful to avoid emergency surgery and provide time for a complete preoperative staging, a metabolic correction and a mechanical bowel preparation. Complications of stent placement are common in many reports and include minor rectal bleeding (2%) and perforations (4%). Stenting is contraindicated in cases of enlarged colon with diameter superior to 8 cm or in flogistic lesions.

[Malignant carcinoid of the last ileal ansa. Report on 2 consecutive clinical cases]. / Il carcinoide maligno dell'ultima ansa ileale. Presentazione di due casi clinici consecutivi.

Carcinoid tumors are very rare neoplasms, arising from enterochromaffin cells, classified in Apud system, exhibiting an intermediate malignancy, because of their long lasting clinical silence and low evolution to advanced stage. At the same time, these features unfortunately cause a high incidence of lymphatic and liver metastases, visible at first diagnostic approach, which are also determined by aspecific symptoms and signs, especially involving jejunal and ileal carcinoids, as the two cases described, and by very frequent absence, in current clinical practice, of pathognomonic carcinoid syndrome. Two carcinoids located into the distal ileal ansa, strictly adjacent to the ileocecal valve, are reported; the first tumor, accompanied by lymphonodal positivity, the second by a solitary hepatic metastasis, requiring segmentectomy of the liver, in addition to right hemicolectomy.

[Common bile duct injuries during videolaparocholecystectomy]. / Le lesioni della via biliare principale in corso di videolaparocolecistectomia.

In the years an increase of last biliary injuries during laparoscopic cholecystectomy was observed. At present this occurrence rate is 0.1-3.4% of laparoscopic procedures. Probably this is to be related to less contraindications to cholecystectomy by laparoscopic procedures, with increase of more difficult operations. The intraoperative biliary injuries are due to anatomical anomalies of the local structures, mistakes of technique, flogosis of the cholecisto-choledocal region. Factors preventing iatrogenic injuries are accurate and standardized operative technique, adoption of modern instruments, intraoperative cholangiography. The Authors have reviewed their experience based on 1236 laparoscopic cholecysectomies performed in six years (1992-1998) in their own structure. Four lesions of the biliary tract (0.3%) have occurred: three Bismuth I-II and one Bismuth IV. They have always performed intraoperative cholangiography, without false negative, in contrast with present literature. They conclude underlining the need of the routine contrastrographic study of the biliary tract in all cholecysectomies as well as of an adequate training in radiological imagines interpretation.

[Errors in digestive surgery. A case of tension pneumothorax during laparoscopic cholecystectomy]. / Errori in chirurgia digestiva. Un caso di pneumotorace sotto tensione durante colecistectomia laparoscopica.

A case of tension pneumothorax caused by an accidental diaphragm injury during laparoscopic cholecystectomy is presented. This complication occurred during one of the first laparoscopic cholecystectomies caused by the crochet abandoned for few seconds, into the peritoneal cavity. Therefore laparoscopy was performed and diaphragm injury repaired.

[Laparoscopic cholecystectomy. Personal experience]. / Colecistectomia laparoscopica. Nostra esperienza.

Personal experience in the treatment of 120 patients submitted to laparoscopic cholecystectomy from March 1992 to September 1993 is presented. The good results obtained suggest that VLC is the best surgical approach for the treatment of cholelithiasis in reason of diminished pain after surgery, shortened hospital stay and early return to work.