Clinical relevance of microhemorrhagic lesions in subacute mild traumatic brain injury.

Magnetic resonance imaging (MRI) is often performed in patients with persistent complaints after mild traumatic brain injury (mTBI). However, the clinical relevance of detected microhemorrhagic lesions is still unclear. In the current study, 54 patients with uncomplicated mTBI and 20 matched healthy controls were included. Post-traumatic complaints were measured at two weeks post-injury. Susceptibility weighted imaging and T2*-gradient echo imaging (at 3 Tesla) were performed at four weeks post-injury. Microhemorrhagic lesions (1-10 mm) were subdivided based on depth (superficial or deep) and anatomical location (frontal, temporoparietal and other regions). Twenty-eight per cent of patients with mTBI had ≥1 lesions compared to 0 % of the healthy controls. Lesions in patients with mTBI were predominantly located within the superficial frontal areas. Number, depth and anatomical location of lesions did not differ between patients with and without post-traumatic complaints. Within the group of patients with complaints, number of complaints was not correlated with number of lesions. In summary, microhemorrhages were found in one out of four patients with uncomplicated mTBI during follow-up at four weeks post-injury, but they were not related to early complaints.

The association between microhaemorrhages and post - traumatic functional outcome in the chronic phase after mild traumatic brain injury.

PURPOSE: In the chronic phase after mild traumatic brain injury (mTBI), microhaemorrhages are frequently detected on magnetic resonance imaging (MRI). It is however unclear whether microhaemorrhages are associated with functional outcome and which MRI sequence is most appropriate to address this association. We aimed to determine the association between microhaemorrhages and functional outcome in the chronic posttraumatic phase after injury with the most suitable MRI sequence to address this association. METHODS: One hundred twenty-seven patients classified with mTBI admitted to the outpatient clinic from 2008 to 2015 for persisting posttraumatic complaints were stratified according to the presence of MRI abnormalities (n = 63 (MRI+ group) and n = 64 without abnormalities (MRI- group)). For the detection of microhaemorrhages, susceptibility-weighted imaging (SWI) and T2* gradient recalled echo (T2*GRE) were used. The relation between the functional outcome (dichotomized Glasgow Outcome Scale Extended scores) and the number and localization of microhaemorrhages was analysed using binary logistic regression. RESULTS: SWI detected twice as many microhaemorrhages compared to T2*GRE: 341 vs. 179. Lesions were predominantly present in the frontal and temporal lobes. Unfavourable outcome was present in 67% of the MRI+ group with a significant association of total number of microhaemorrhages in the temporal cortical area on SWI (OR 0.43 (0.21-0.90) p = 0.02), with an explained variance of 44%. The number of microhaemorrhages was not correlated with the number of posttraumatic complaints. CONCLUSION: An unfavourable outcome in the chronic posttraumatic phase is associated with the presence and number of microhaemorrhages in the temporal cortical area. SWI is preferably used to detect these microhaemorrhages.

Do deficits in the magnocellular priming underlie visual derealization phenomena? Preliminary neurophysiological and self-report results in first-episode schizophrenia patients.

BACKGROUND: Early visual impairments probably partially caused by impaired interactions between magnocellular (M) and parvocellular (P) pathways (M priming deficit), and disturbances of basic self-awareness or self-disorders (SDs) are core features of schizophrenia. The relationships between these features have not yet been studied. We hypothesized that the M priming was impaired in first-episode patients and that this deficit was associated with visual aspects of SDs. AIM: To investigate early visual processing in a sample of first-episode schizophrenia patients and to explore the relationships between M and P functioning and visual aspects of SDs addressed by the Examination of Anomalous Self-Experience (EASE) interview. METHOD: Nine stimulating conditions were used to investigate M and P pathways and their interaction in a pattern reversal visually evoked potential (VEP) paradigm. N80 at mixed M- and P-conditions was used to investigate magnocellular priming. Generators were analyzed using source localization (Brain Electrical Source Analysis software: BESA). VEPs of nineteen first-episode schizophrenia patients were compared to those of twenty matched healthy controls by a bootstrap resample procedure. Visual aspects of SDs were analyzed through a factor analysis to separate symptom clusters of derealization phenomena. Thereafter, the associations between the main factors and the N80 component were explored using linear mixed models. RESULTS: Factor analyses separated two EASE factors ("distance to the world", and "intrusive world"). The N80 component was represented by a single dipole located in the occipital visual cortex. The bootstrap analysis yielded significant amplitude reductions and prolonged latencies in first-episode patients relative to controls in response to mixed M-P conditions, and normal amplitudes and latencies in response to isolated P- and M-biased stimulation. Exploratory analyses showed significant negative correlations between the N80 amplitude values at mixed M-P conditions and the EASE factor "distance to the world", i.e. relatively higher amplitudes in the patient group were associated with higher subjective perceived derealization ("distance to the world"). CONCLUSIONS: The early VEP component N80 evoked by mixed M-P conditions is assumed to be a correlate of M priming, and showed reduced amplitudes and longer latencies in first-episode patients. It probably reflects a hypoactivation of the M-pathway. The negative association between visual SDs (derealization phenomena characterized by visual experiences of being more distant to the world), and the M priming deficit was counterintuitive. It might indicate a dysregulated activity of the M-pathway in patients with SDs. Further research is needed to better understand this preliminary finding.

Assessment of left ventricular ejection fraction in patients eligible for ICD therapy: Discrepancy between cardiac magnetic resonance imaging and 2D echocardiography.

OBJECTIVE: Implantable cardioverter defibrillators (ICD) and cardiac resynchronisation therapy (CRT) have substantially improved the survival of patients with cardiomyopathy. Eligibility for this therapy requires a left ventricular ejection fraction (LVEF) <35 %. This is largely based on studies using echocardiography. Cardiac magnetic resonance imaging (CMR) is increasingly utilised for LVEF assessment, but several studies have shown differences between LVEF assessed by CMR and echocardiography. The present study compared LVEF assessment by CMR and echocardiography in a heart failure population and evaluated effects on eligibility for device therapy. METHODS: 152 patients (106 male, mean age 65.5 ± 9.9 years) referred for device therapy were included. During evaluation of eligibility they underwent both CMR and echocardiographic LVEF assessment. CMR volumes were computed from a stack of short-axis images. Echocardiographic volumes were computed using Simpson's biplane method. RESULTS: The study population demonstrated an underestimation of end-diastolic volume (EDV) and end-systolic volume (ESV) by echocardiography of 71 ± 53 ml (mean ± SD) and 70 ± 49 ml, respectively. This resulted in an overestimation of LVEF of 6.6 ± 8.3 % by echocardiography compared with CMR (echocardiographic LVEF 31.5 ± 8.7 % and CMR LVEF 24.9 ± 9.6 %). 28 % of patients had opposing outcomes of eligibility for cardiac device therapy depending on the imaging modality used. CONCLUSION: We found EDV and ESV to be underestimated by echocardiography, and LVEF assessed by CMR to be significantly smaller than by echocardiography. Applying an LVEF cut-off value of 35 %, CMR would significantly increase the number of patients eligible for device implantation. Therefore, LVEF cut-off values might need reassessment when using CMR.

Influence of repeated maximal exercise testing on biomarkers and fatigue in sarcoidosis.

Fatigue in the immune mediated inflammatory disease sarcoidosis is thought to be associated with impaired exercise tolerance. This prospective study assessed fatigue and recuperative capacity after repeated exercise, and examined whether changing concentrations in biomarkers upon exercise are associated with fatigue. Twenty sarcoidosis patients and 10 healthy volunteers performed maximal cardiopulmonary exercise tests on two successive days. Concentrations of cytokines, stress hormones, ACE and CK were assessed before and after the two exercise tests, and 3 days thereafter. All participants completed a sleep diary. Severely fatigued patients showed significant lower VO2 max (p=0.038, p=0.022) and maximal workload (p=0.034, p=0.028) on both exercise tests compared to healthy controls. No impairment of maximal exercise testing was demonstrated during the second cycling test in any group. Fatigue was not correlated with changes in concentrations of biomarkers upon exercise. Severely fatigued patients rated both tests as significantly more fatiguing, and reported significant lower mean subjective night sleeping time during the testing period. Fatigue in sarcoidosis patients cannot be objectified by reduction of exercise capacity after repeated maximal exercise testing, and is not correlated with significant changes in biomarkers. Severe fatigue is only and consistently featured by patient reported outcomes.

[Self-experience in the early phase of psychosis: a phenomenological approach]. / Zelfbeleving in de vroege fase van psychose: een fenomenologische benadering.

BACKGROUND: The early detection of psychotic disorders is seen to be increasingly important. Authors of recent articles are adopting a phenomenological approach, taking the view that changes in self-experience represent a major prodromal feature of psychotic disorders. AIM: To find out what a phenomenological approach can contribute to the study of the early phase of psychotic disorders. METHOD: We discuss the literature that explores to what extent changes in self-experience are a central phenomenon in the prodromal phase of psychotic disorders. We also present a phenomenological model that explains these changes. RESULTS: Characteristic changes in self-experience during the prodromal phase of psychotic disorders can provide the framework for an empirical, phenomenological explanatory model. CONCLUSION: In an empirical, phenomenological approach early changes in a patient’s self-experience are considered to play a central role. There are some indications that semi-structured interviews focusing on changes in a patient’s self-experience can contribute to the early detection of psychotic disorders.

Cardiac PET-CT: advanced hybrid imaging for the detection of coronary artery disease.

Hybrid imaging of positron emission tomography (PET) together with computed tomography (CT) is rapidly emerging. In cardiology, this new advanced hybrid imaging modality allows quantification of cardiac perfusion in combination with assessment of coronary anatomy within a single scanning session of less than 45 minutes. The near-simultaneous anatomical evaluation of coronary arteries using CT and corresponding functional status using PET provides a wealth of complementary information in patients who are being evaluated for (suspected) coronary artery disease, and could help guide clinical patient management in a novel manner. Clinical experience gained with this recently introduced advanced hybrid imaging tool, however, is still limited and its implementation into daily clinical practice remains largely unchartered territory. This review discusses principles of perfusion PET, its diagnostic accuracy, and potential clinical applications of cardiac PET-CT in patients with ischaemic heart disease. (Neth Heart J 2010;18:90-8.).

[Diagnostic methods for Helicobacter pylori infection in children]. / Diagnostiek naar Helicobacter pylori-infectie bij kinderen.

A Helicobacter pylori infection is usually acquired during early childhood. Poor socioeconomic circumstances form an important risk factor for this. An untreated infection may lead to peptic ulceration and, particularly in adults, to gastric cancer and mucosa associated lymphoid tissue (MALT) lymphoma. The gold standard for the diagnosis of H. pylori infection is gastroscopy with histology and culture of biopsy specimens. Non-invasive tests are serology, 13C-urea breath test and stool antigen test. The sensitivity and specificity of serology tests are low in children, but for both the 13C-urea breath test and the stool antigen test the sensitivity and specificity are high. A 'test and treat' approach is advised with due consideration for possible symptoms and the risk for peptic ulcers and gastric cancer at a more advanced age. The treatment results must be evaluated. If necessary, young children can be treated at a later age.

Rectification in mesoscopic systems with broken symmetry: quasiclassical ballistic versus classical transport.

In suitably designed mesoscopic semiconductor structures, the phenomenon of ballistic rectification can be observed. A currently discussed microscopic model relates the observations to the interplay between fully quantized and quasiclassical current paths. We present measurements that contribute substantially to the clarification of the fascinating topic. In particular, we observe the opposite sign of the output voltage as compared to the prediction. Demonstrating the basic principle upon which the rectification is based--the asymmetry of the voltage drop in a quasiclassical wire--and extending the model to the classical transport regime, we can well explain our experiments as being caused by the interplay of quasiclassical ballistic and classical transport. Tunable ballistic rectifiers generating very large output signals and operating at room temperature raise the hope for future applications.

Chemoprophylaxis of depressions. An attempt to compare lithium with 5-hydroxytryptophan.

There are indications that the group of vital ('endogenous') depressions encompasses a subgroup with central 5-HT deficiency and that this factor contributes to the development of the (or some) depressive symptoms instead of resulting from them. In a majority of patients the suspected 5-HT deficiency persists even when the depressive symptoms have disappeared and the medication has been discontinued. This led us to the hypothesis that the disturbed central 5-HT metabolism is not a direct causal, but a predisposing factor. If this is true, then abolition of the suspected 5-HT deficiency, for example with the aid of 5-HTP, can be expected to have a prophylactic effect. This hypothesis was investigated in this study and confirmed. 5-HTP reduces the relapse rate in recurrent vital depressions with a unipolar and those with a bipolar course. This effect would seem to be most pronounced in patients whose disorders of central 5-HT metabolism are persistent. Tentatively it was concluded that 5-HTP seems to be inferior to lithium in bipolar patients and at least equivalent to lithium in unipolar patients. This problem, however, is still under investigation. 5-HTP prophylaxis is the first aimed (i.e. pathological substrate-oriented) type of chemoprophylaxis known in psychiatry.

Central serotonin metabolism and frequency of depression.

Central serotonin (5-hydroxytryptamine; 5-HT) metabolism can be disturbed in a subgroup of patients with vital (endogenous, primary) depression. Presumably these disturbances do not result from the depression and have a predisposing rather than a causative relationship to it. This latter statement is based on two observations. First, in a majority of patients, the 5-HT disturbances persist after depression has abated. Secondly, 5-hydroxytryptophan seems to have prophylactic value, in particular in patients with persistent abnormalities in central 5-HT metabolism. In this study we approached the hypothesis that 5-HT disturbances are a predisposing factor to the occurrence of depression from still another perspective. If this hypothesis is correct, then depressive patients with persistent 5-HT disturbances should have higher frequencies of depression than depressive patients without demonstrable 5-HT disturbances. This was indeed demonstrated. The same was true for family members of probands with low levels of 5-hydroxyindoleacetic acid. No cerebrospinal fluid data are available for family members. The reported findings strongly support the predisposition hypothesis.