Near Infrared Spectroscopy and Electroencephalography For an Assessment of Brain Function in patients with Disorders of Consciousness

There is growing evidence that some of the patients presenting with the Vegetative State (VS), also known as Unresponsive Wakefulness State, can respond to environmental stimuli. This response can be detected by using functional brain imaging, including electroencephalography (EEG) or Near Infrared Spectroscopy (NIRS). By definition, the VS patients are awake but not aware, unlike the patients in the Minimally Conscious State (MCS), who have some fluctuating awareness. Since consciousness is impaired in both conditions, these states are also referred as Disorders of Consciousness (DOC) or prolonged Disorders of Consciousness (pDOC) This thesis aims to develop a bedside applicable tool using the EEG and NIRS for brain function assessment in VS and MCS patients. In this study, two experimental protocols have been developed and validated on healthy subjects. The results showed that using the motor imagery and own subject name stimuli, some of the VS patients were able to wilfully modulate their brain activity in response to those stimuli. The results presented in this thesis can be implemented as a part of a protocol for brain function assessment in pDOC patients and can be used for the further studies for better understanding of the brain function in these patients

Hypoalbuminaemia predicts outcome in adult patients with congenital heart disease

Background In patients with acquired heart failure, hypoalbuminaemia is associated with increased risk of death. The prevalence of hypoproteinaemia and hypoalbuminaemia and their relation to outcome in adult patients with congenital heart disease (ACHD) remains, however, unknown. Methods Data on patients with ACHD who underwent blood testing in our centre within the last 14 years were collected. The relation between laboratory, clinical or demographic parameters at baseline and mortality was assessed using Cox proportional hazards regression analysis. Results A total of 2886 patients with ACHD were included. Mean age was 33.3 years (23.6–44.7) and 50.1% patients were men. Median plasma albumin concentration was 41.0 g/L (38.0–44.0), whereas hypoalbuminaemia (<35 g/L) was present in 13.9% of patients. The prevalence of hypoalbuminaemia was significantly higher in patients with great complexity ACHD (18.2%) compared with patients with moderate (11.3%) or simple ACHD lesions (12.1%, p<0.001). During a median follow-up of 5.7 years (3.3–9.6), 327 (11.3%) patients died. On univariable Cox regression analysis, hypoalbuminaemia was a strong predictor of outcome (HR 3.37, 95% CI 2.67 to 4.25, p<0.0001). On multivariable Cox regression, after adjusting for age, sodium and creatinine concentration, liver dysfunction, functional class and disease complexity, hypoalbuminaemia remained a significant predictor of death. Conclusions Hypoalbuminaemia is common in patients with ACHD and is associated with a threefold increased risk of risk of death. Hypoalbuminaemia, therefore, should be included in risk-stratification algorithms as it may assist management decisions and timing of interventions in the growing ACHD population

CT2TEE - internetowy symulator echokardiografii przezprzełykowej we wrodzonych wadach serca

Background: Echocardiography is one of the most important diagnostic tools in cardiology. The two most widespread modes of echocardiography are transthoracic (TTE) and transoesophageal (TEE) echocardiography, both requiring extensive training. In TEE the manual skills seem to be less important, but it is more challenging for the trainee to imagine the orientation of the cutting planes in space. This becomes more complicated, even for an experienced echocardiographer, in patients with congenital heart disease. There is a growing interest in TEE simulators. All of them are, however, manikin based and their use is limited to only a few medical centres. Aim: To develop an internet-based TEE simulator offering interactive training in cases with and without congenital heart disease. Methods: Because of high spatial resolution we use data from ECG-triggered heart computed tomography (CT) to build the 3D heart model. On every CT image the oesophagus has to be marked and the greyscale values converted in order to mimic the tissue greyscales seen in TEE. After such preparations the 3D set created from CT data can be cut in any plane. The trainee can use the slider buttons in the simulator interface to freely steer the virtual TEE probe. While setting the desired TEE plane the application conducts calculations in order to simulate the typical sonographic artefacts. Results: We were able to construct an application allowing a TEE simulation based on CT data. There are two versions of the simulator. The first one has to be downloaded to a personal computer together with the CT data. The second one is internet based and freely accessible on the project&#8217;s web page (www.ct2tee.agh.edu.pl). It doesn&#8217;t offer real time simulation, but is sufficient to obtain all possible views in the TEE. There are currently three data sets, two with congenital heart disease, and further development of the database and simulator is planned. Conclusions: The CT2TEE simulator, described in this paper, is the first fully interactive, internet-based TEE simulator. It can be a training tool both in learning TEE basics and in congenital heart disease

“With A Little Help From My (Online?) Friends” – A Comparison of Support Seeking, Receiving and Providing Support in Online and Offline Communities

Social networking services (SNS) like Facebook are used by an increasing number of people worldwide for social exchange. Given the amount of time that is spent on these online services, they are likely to have an impact on how individuals interact with each other. On this note, anecdotal examples emphasize both positive (i.e., expanding or strengthening relationships) and negative effects (i.e., bullying, feelings of disconnectedness). To shed more light on this issue, scholars from various disciplines have started to investigate the significance of social networking services on interpersonal relationships and on how individuals might experience benefits on the one hand, or face challenges through the use of online services on the other hand [1, 2]. One research interest that has gained significant attention in recent years is the analysis of effects that social networks may have on the quantity and quality of interpersonal online social support in different contexts. [... from the introduction

The expression of VvMYBPA1 in tobacco remodulates the phenylpropanoid pathway and diverts the synthesis of anthocyanins into condensed tannins in flowers

Patients in Vegetative State (VS), also known as Unresponsive Wakefulness State (UWS) are deemed to be unaware of themselves or their environment. This is different from patients diagnosed with Minimally Conscious state (MCS), who can have intermittent awareness. In both states, there is a severe impairment of consciousness; these disorders are referred to as disorders of consciousness (DOC) and if the state is prolonged, pDOC. There is growing evidence that some patients who are behaviourally in VS/UWS can show neural activation to environmental stimuli and that this response can be detected using functional brain imaging (fMRI/PET) and electroencephalography (EEG). Recently, it has also been suggested that a more reliable detection of brain responsiveness and hence a more reliable differentiation between VS/UWS and MCS requires person-centred and person-specific stimuli, such as the subject's own name stimulus.In this study we obtained event related potential data (ERP) from 12 healthy subjects and 16 patients in pDOC, five of whom were in the VS/UWS and 11 in the Minimally Conscious State (MCS). We used as the ERP stimuli the subjects' own name, others' names and reversed other names. We performed a sensor level analysis using Statistical Parametric Mapping (SPM) software. Using this paradigm in 4 DOC patients (3 in MCS, and 1 in VS/UWS) we detected a statistically significant difference in EEG response to their own name versus other peoples' names with ERP latencies (~300 ms and ~700 ms post stimuli). Some of these differences were similar to those found in a control group of healthy subjects.This study shows the feasibility of using self-relevant stimuli such as a subject's own name for assessment of brain function in pDOC patients. This neurophysiological test is suitable for bed-side/hospital based assessment of pDOC patients. As it does not require sophisticated scanning equipment it can feasibly be used within a hospital or care setting to help professionals tailor medical and psycho-social management for patients

Functional near infrared spectroscopy as a probe of brain function in people with prolonged disorders of consciousness

Near infrared spectroscopy (NIRS) is a non-invasive technique which measures changes in brain tissue oxygenation. NIRS has been used for continuous monitoring of brain oxygenation during medical procedures carrying high risk of iatrogenic brain ischemia and also has been adopted by cognitive neuroscience for studies on executive and cognitive functions. Until now, NIRS has not been used to detect residual cognitive functions in patients with prolonged disorders of consciousness (pDOC). In this study we aimed to evaluate the brain function of patients with pDOC by using a motor imagery task while recording NIRS. We also collected data from a group of age and gender matched healthy controls while they carried out both real and imagined motor movements to command. We studied 16 pDOC patients in total, split into two groups: five had a diagnosis of Vegetative state/Unresponsive Wakefulness State, and eleven had a diagnosis of Minimally Conscious State. In the control subjects we found a greater oxy-haemoglobin (oxyHb) response during real movement compared with imagined movement. For the between group comparison, we found a main effect of hemisphere, with greater depression of oxyHb signal in the right > left hemisphere compared with rest period for all three groups. A post-hoc analysis including only the two pDOC patient groups was also significant suggesting that this effect was not just being driven by the control subjects. This study demonstrates for the first time the feasibility of using NIRS for the assessment of brain function in pDOC patients using a motor imagery task