IntroductionBurst-suppression (BS) is an electroencephalography (EEG) pattern consisting of alternant periods of slow waves of high amplitude (burst) and periods of so called flat EEG (suppression). It is generally associated with coma of various etiologies (hypoxia, drug-related intoxication, hypothermia, and childhood encephalopathies, but also anesthesia). Animal studies suggest that both the cortex and the thalamus are involved in the generation of BS. However, very little is known about mechanisms of BS in humans. The aim of this study was to identify the neuronal network underlying both burst and suppression phases using source reconstruction and analysis of functional and effective connectivity in EEG.Material/MethodsDynamic imaging of coherent sources (DICS) was applied to EEG segments of 13 neonates and infants with burst and suppression EEG pattern. The brain area with the strongest power in the analyzed frequency (1–4 Hz) range was defined as the reference region. DICS was used to compute the coherence between this reference region and the entire brain. The renormalized partial directed coherence (RPDC) was used to describe the informational flow between the identified sources.Results/ConclusionDelta activity during the burst phases was associated with coherent sources in the thalamus and brainstem as well as bilateral sources in cortical regions mainly frontal and parietal, whereas suppression phases were associated with coherent sources only in cortical regions. Results of the RPDC analyses showed an upwards informational flow from the brainstem towards the thalamus and from the thalamus to cortical regions, which was absent during the suppression phases. These findings may support the theory that a “cortical deafferentiation” between the cortex and sub-cortical structures exists especially in suppression phases compared to burst phases in burst suppression EEGs. Such a deafferentiation may play a role in the poor neurological outcome of children with these encephalopathies.

We conclude that HTT measurements using contrast enhanced MRI with Gd-BOPTA can detect hemodynamic changes due to metastatic liver disease from colorectal cancer.

In a clinical-experimental study the influence of variations in the palatal shape of upper removable appliances upon tongue position during swallowing was investigated. During a clinical examination of 35 dental students displaying a physiological swallowing pattern, the tongue position during swallowing was recorded by palatography on an individually adapted upper plate. During swallowing with a roughened plate with an individual palatal shape and an imitated palatal papilla, the tongue position was significantly more posterior than with a highly polished, unstructured plate. The number of students displaying a visceral swallowing pattern was significantly smaller with a roughened plate with palatal folds and papilla then with a polished, smooth appliance. A roughened, individually shaped appliance with palatal folds and palatal papilla should therefore be used after myofunctional therapy and in cases where disturbance of tongue function by the appliance is not desirable.