Hallucinations in neurodegenerative diseases

Patients with neurodegenerative disease frequently experience hallucinations and illusionary perceptions. As early symptoms, hallucinations may even have diagnostic relevance (i.e., for the diagnosis of Lewy Body Dementia). In the later course of the disease, hallucinations may appear as characteristic symptoms and often constitute a particular challenge for therapeutic endeavors. Here, the distinction of disease-inherent hallucinations from medication-associated perceptual disturbances is particularly relevant. Synucleinopathies and tauopathies have different risk profiles for hallucinations. In synucleinopathies hallucinations are much more frequent and phenomenology is characterized by visual, short-lived hallucinations, with insight preserved for a long time. A “double hit” theory proposes that dysfunctionality of both associative visual areas and changes of limbic areas or the ventral striatum are required. In contrast, in tauopathies the hallucinations are more rare and mostly embedded in confusional states with agitation and with poorly defined or rapidly changing paranoia. The occurrence of hallucinations has even been proposed as an exclusion criterion for tauopathies with Parkinsonian features such as progressive supranuclear palsy. To date, treatment remains largely empirical, except the use of clozapine and cholinesterase inhibitors in synucleinopathies, which is evidence-based. The risk of increased neuroleptic sensitivity further restricts the treatment options in patients with Lewy Body Dementia. Coping Strategies and improvement of visual acuity and sleep quality may be useful therapeutic complements.     

Comparison of functional and cytoarchitectonic maps of human visual areas V1, V2, V3d,V3v,and V4(v)

Cytoarchitectonic maps of human striate and extrastriate visual cortex based upon post-mortem brains can be correlated with functionally defined cortical areas using, for example, fMRI. We here assess the correspondence of anatomical maps of the visual cortex with functionally defined in vivo visual areas using retinotopic mapping. To this end, anatomical maximum probability maps (aMPM) derived from individual cytoarchitectonic maps of striate and extrastriate visual areas were compared with functional localisers for the early visual areas. Using fMRI, we delineated dorsal and ventral human retinotopic areas V1, V2, and V3, as well as a quarter-field visual field representation lateral to V3v, V4(v), in 24 healthy subjects. Based on these individual definitions, a functional maximum probability map (fMPM) was then computed in analogy to the aMPM. Functional and anatomical MPMs were highly correlated at group level: 78.5% of activated voxels in the fMPM were correctly assigned by the aMPM. The group aMPM was less effective in predicting functional retinotopic areas in the individual brain due to the large inter-individual variability in the location and extent of visual areas (mean overlap 32–69%). We conclude that cytoarchitectonic maps of striate and extrastriate visual areas may provide a valuable method for assigning functional group activations and thus add valuable a priori knowledge to the analysis of functional imaging data of the visual cortex.     

Feeding disorders in ex-prematures: causes - response to therapy - long term outcome

Feeding disorders in ex-prematures do exist and may constitute a major challenge to their families’ well being. A cases series of 86 ex-prematures with severe feeding disorders was analysed regarding co-morbidity, response to therapy and the long-term outcome after treatment. These children with a gestational age of <37 weeks had been referred for hospital rehabilitation because of severe feeding disorders, defined as tube feeding or average feeding times of more than 30 minutes. Behavioural therapy was the key element of the treatment. Ex-prematures accounted for 86/266 patients admitted for treatment of feeding disorders between 1995 and 2004. Whereas only 40.8% of these had cerebral palsy, 51.1% had a diagnosis of mental retardation and 87% had interaction problems. Response to treatment up to discharge was achieved in 61.6%. Univariat analyses showed that tube feeding at admission and swallowing difficulties were the best predictors of failure to respond to the intervention. Long-term follow-up data that were collected for 53 of the 86 children with similar initial response to therapy (64.2%) compared to children with no follow-up data (57.6%). Success of therapy after discharge was maintained in 94.1%; however, 25% of the children with normal BMI’s at discharge and sustained success of therapy fell below the 3rd BMI percentile. Cerebral palsy, mental retardation and interaction problems appear to be important risk factors for severe feeding disorders in ex-prematures. A therapeutic intervention based on behavioural therapy achieved sustained success in almost two thirds of the children.     

Convergence of human brain mapping tools: neuronavigated TMS parameters and fMRI activity in the hand motor area

Functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) are well-established tools for investigating the human motor system in-vivo. We here studied the relationship between movement-related fMRI signal changes in the primary motor cortex (M1) and electrophysiological properties of the hand motor area assessed with neuronavigated TMS in 17 healthy subjects. The voxel showing the highest task-related BOLD response in the left hand motor area during right hand movements was identified for each individual subject. This fMRI peak voxel in M1 served as spatial target for coil positioning during neuronavigated TMS. We performed correlation analyses between TMS parameters, BOLD signal estimates and effective connectivity parameters of M1 assessed with dynamic causal modeling (DCM). The results showed a negative correlation between the movement-related BOLD signal in left M1 and resting as well as active motor threshold (MT) obtained for left M1. The DCM analysis revealed that higher excitability of left M1 was associated with a stronger coupling between left supplementary motor area (SMA) and M1. Furthermore, BOLD activity in left M1 correlated with ipsilateral silent period (ISP), i.e. the stronger the task-related BOLD response in left M1, the higher interhemispheric inhibition effects targeting right M1. DCM analyses revealed a positive correlation between the coupling of left SMA with left M1 and the duration of ISP. The data show that TMS parameters assessed for the hand area of M1 do not only reflect the intrinsic properties at the stimulation site but also interactions with remote areas in the human motor system.     

Der richtige Umgang mit dem definitiven chirurgischen Atemweg

Die Anaesthesiologie - Der schwierige Atemweg kann Notfallmediziner*innen prä- und innerklinisch jederzeit begegnen. In der Anästhesiologie haben sich hierzu verschiedene Algorithmen...     

Psychiatric disorders after an accident: predictors and the influence of the psychiatric condition prior to an accident

BACKGROUND: The goal of this study is to assess prevalence and incidence of psychiatric sequelae in a sample of inpatient accident survivors. Such an attempt to assess psychiatric conditions that originate due to an accident seems to be important; this does not include psychiatric conditions already present prior to the accident. METHOD: 208 accident victims were consecutively examined over a period of 12months using DSM-IV diagnostic assessment, CAPS, and self-evaluating questionnaires as well as ISS for injury severity. A predictor model for psychiatric disorders was set up. RESULTS: Incidence of newly developed Axis I disorders in our sample was 14.2% (6months) and 12.3% (12months). Incidence of PTSD was 5.9% (6months) and 2.5% (12months). Comorbidity was a general phenomenon. The psychiatric condition prior to the accident could be identified as a predictor for the development of Axis I disorders. The subjectively evaluated intensity of experienced threat to life and female gender were the main predictors for the development of PTSD. CONCLUSIONS: Accidents can lead to different psychiatric disorders. PTSD as a single diagnosis is rare. Without taking into account pre-existing disorders, the incidence may be overestimated. Two predictor models for the development of PTSD and other mental disorders are presented.