Does cerebrospinal fluid pulsation affect diffusion-weighted imaging thermometry? A study in healthy volunteers

Diffusion-weighted imaging (DWI)-based thermometry offers potential as a noninvasive method for measuring temperatures deep inside the human brain. However, DWI might be influenced by the pulsatile flow of cerebrospinal fluid (CSF). This study aimed to investigate the influence of such pulsations on DWI thermometry in healthy individuals. A total of 104 participants (50 men, 54 women; mean [± standard deviation] age, 44.2 ± 14.3 years; range 21–69 years) were investigated. DWI-based brain temperature (T_DWI) was acquired at three speeds (maximum and minimum speeds of ascending flow and random timing at the cerebral aqueduct) of CSF pulsation using a 3-T magnetic resonance imaging scanner. Magnetic resonance spectroscopy (MRS)-based temperature (T_MRS) at the thalamus was also obtained as a reference standard for brain temperature. The three different CSF pulsatile flows were monitored by heart rate during the scan. The difference between reference temperature and brain temperature (ΔT = T_DWI– T_MRS) along with the three CSF speeds were statistically compared using Student's matched pair t-test. No significant difference in ΔT was evident among CSF speeds (p > 0.05). No significant linear correlation between ΔT and CSF flow speed at the cerebral aqueduct was observed. Using DWI thermometry with clinical acquisition settings, which utilizes mean values within thresholds, no effect of CSF pulsation speed was observed in the estimation of ΔT.     

Structure-function relationships in the context of reinforcement-related learning: a combined diffusion tensor imaging–functional magnetic resonance imaging study

In the context of probabilistic learning, previous functional magnetic resonance imaging studies have shown decreasing uncertainty accompanying decreasing neuronal activation in task-relevant networks. Moreover, initial evidence points to a relationship between white matter structure and cognitive performance. Little is known, however, about the structural correlates underlying individual differences in activation and performance in the context of probabilistic learning. This combined functional magnetic resonance imaging–diffusion tensor imaging study aimed at investigating the individual ability to reduce processing resources with decreasing uncertainty in direct relation to individual characteristics in white matter brain structure. Results showed that more successful learners, as compared with less successful learners, exhibited stronger activation decreases with decreasing uncertainty. An increased mean and axial diffusivity in, among others, the inferior and superior longitudinal fasciculus, the posterior part of the cingulum bundle, and the corpus callosum were detectable in less successful learners compared with more successful learners. Most importantly, there was a negative correlation between uncertainty-related activation and diffusivity in a fronto-parieto-striatal network in less successful learners only, indicating a direct relation between diffusivity and the ability to reduce processing resources with decreasing uncertainty. These findings indicate that interindividual variations in white matter characteristics within the normal population might be linked to neuronal activation and critically influence individual learning performance.     

Are high lumbar punctures safe? A magnetic resonance imaging morphometric study of the conus medullaris

A high lumbar puncture (LP) at L2–L3 or above is often necessary to consider on technical grounds, but complications of conus medullaris (CM) damage during high LP are potentially concerning. We hypothesized that a high LP might be safer than previously thought by accounting for movements of the CM upon patient positional changes. We retrospectively reviewed standard normal supine lumbar spine magnetic resonance imaging of 58 patients and used electronic calipers on axial images at the T12–L1, L1–L2, and L2–L3 disc levels to measure the transverse diameter of the CM relative to the size of the dorsal thecal sac space (DTSS) through which a spinal needle could be inserted. On 142 axial images, the means for CM diameters were 8.2, 6.0, and 2.9 mm at the three levels, respectively. We then used known literature mean CM displacement values in the legs flexed and unflexed lateral decubitus position (LDP) to factor in CM shifts to the dependent side. We found that at all three levels, the likely positional shift of the CM would be too small and insufficient to displace the entire CM out of the DTSS. However, if needle placement could be confined to the midsagittal plane, an LP in the unflexed LDP would theoretically be entirely safe at both L1–L2 and L2–L3, and almost so at L2–L3 in the legs flexed LDP. Thus, high LPs at L1–L2 and L2–L3 are in theory likely safer than considered previously, more so in the legs unflexed than in the flexed LDP. Clin. Anat. 32:618–629, 2019. © 2019 Wiley Periodicals, Inc.     

Is a neutral expression also a neutral stimulus? A study with functional magnetic resonance

Although neutral faces do not initially convey an explicit emotional message, it has been found that individuals tend to assign them an affective content. Moreover, previous research has shown that affective judgments are mediated by the task they have to perform. Using functional magnetic resonance imaging in 21 healthy participants, we focus this study on the cerebral activity patterns triggered by neutral and emotional faces in two different tasks (social or gender judgments). Results obtained, using conjunction analyses, indicated that viewing both emotional and neutral faces evokes activity in several similar brain areas indicating a common neural substrate. Moreover, neutral faces specifically elicit activation of cerebellum, frontal and temporal areas, while emotional faces involve the cuneus, anterior cingulated gyrus, medial orbitofrontal cortex, posterior superior temporal gyrus, precentral/postcentral gyrus and insula. The task selected was also found to influence brain activity, in that the social task recruited frontal areas while the gender task involved the posterior cingulated, inferior parietal lobule and middle temporal gyrus to a greater extent. Specifically, in the social task viewing neutral faces was associated with longer reaction times and increased activity of left dorsolateral frontal cortex compared with viewing facial expressions of emotions. In contrast, in the same task emotional expressions distinctively activated the left amygdale. The results are discussed taking into consideration the fact that, like other facial expressions, neutral expressions are usually assigned some emotional significance. However, neutral faces evoke a greater activation of circuits probably involved in more elaborate cognitive processing.     

Functional magnetic resonance imaging study reveals differences in the habituation to psychological stress in patients with Crohn’s disease versus healthy controls

In patients with Crohn’s disease (CD) stress is believed to increase the incidence of disease relapse. The brain processes stressful stimuli and triggers the stress-evoked responses. Habituation to stress is an adaptive process that allows minimizing these responses. We hypothesized inadequate habituation to stress in CD patients. The aim of this study was to compare the neural habituation between CD patients and controls. Twenty CD patients and eighteen controls underwent a functional magnetic resonance imaging while performing two repeated runs of a stress-evoking task. The task elicited different neural activity between the groups across runs in (1) amygdala, hippocampus, (2) insula, putamen (3) cerebellar regions, suggesting altered habituation to stress in patients. These structures regulate the neuroendocrine and autonomic stress-evoked responses that control the proinflammatory responses. The inadequate habituation to stress that we found in patients could play a role in the relationship between stress and inflammatory exacerbations in CD.     

Is there evidence for a male depressive syndrome in inpatients with major depression?

BACKGROUND: The question is investigated whether atypical depressive symptoms such as irritability, anger attacks, aggressiveness or abusive behavior, which are hypothesized to indicate a hypothetical male depressive syndrome are more prevalent in male than in female inpatients with unipolar major depression. METHODS: Data were obtained from 2411 patients who had been consecutively admitted to the Department of Psychiatry of the Ludwig-Maximilians-University of Munich. Psychopathological symptoms had been assessed by a standardized documentation system (AMDP). RESULTS: Neither frequency nor mean scores of most of the symptoms describing a male depressive syndrome differed between males and females. There were no gender differences in symptoms with respect to severity of depression, first hospitalization and duration of illness. However, gender differences emerged when regarding symptom patterns by factor analysis. Limitations: Only inpatients were studied, and comorbidity was not considered. CONCLUSIONS: The hypothesis of a male depressive syndrome needs further research, focusing on the gradual development of (masked) depression by men in mainly non-clinical samples.     

Is gene panel sequencing more efficient than clinical‐based gene sequencing to diagnose autoinflammatory diseases? A randomized study

The aim of this study was to compare the effectiveness of the gene‐panel next‐generation sequencing (NGS) strategy versus the clinical‐based gene Sanger sequencing for the genetic diagnosis of autoinflammatory diseases (AIDs). Secondary goals were to describe the gene and mutation distribution in AID patients and to evaluate the impact of the genetic report on the patient’s medical care and treatment. Patients with AID symptoms were enrolled prospectively and randomized to two arms, NGS (n = 99) (32–55 genes) and Sanger sequencing (n = 197) (one to four genes). Genotypes were classified as ‘consistent/confirmatory’, ‘uncertain significance’ or ‘non‐contributory’. The proportion of patients with pathogenic genotypes concordant with the AID phenotype (consistent/confirmatory) was significantly higher with NGS than Sanger sequencing [10 of 99 (10·1%) versus eight of 197 (4·1%)]. MEFV, ADA2 and MVK were the most represented genes with a consistent/confirmed genotype, whereas MEFV, NLRP3, NOD2 and TNFRSF1A were found in the ‘uncertain significance’ genotypes. Six months after the genetic report was sent, 54 of 128 (42·2%) patients had received effective treatment for their symptoms; 13 of 128 (10·2%) had started treatment after the genetic study. For 59 of 128 (46%) patients, the results had an impact on their overall care, independent of sequencing group and diagnostic conclusion. Targeted NGS improved the diagnosis and global care of patients with AIDs.     

Is there evidence for neural compensation in attention deficit hyperactivity disorder? A review of the functional neuroimaging literature

This article reviews evidence for the presence of a compensatory, alternative, neural system and its possible link to associated processing strategies in children and adults with attention deficit hyperactivity disorder (ADHD). The article presents findings on a region by region basis that suggests ADHD should be characterized not only by neural hypo-activity, as it is commonly thought but neural hyperactivity as well, in regions of the brain that may relate to compensatory brain and behavioral functioning. In this context studies from the functional neuroimaging literature are reviewed. We hypothesize that impaired prefrontal (PFC) and anterior cingulate (ACC) cortex function in ADHD reduces the ability to optimally recruit subsidiary brain regions and strategies to perform cognitive tasks. The authors conclude that healthy individuals can recruit brain regions using visual, spatial or verbal rehearsal for tasks as needed. In contrast, individuals with ADHD may be less able to engage higher order executive systems to flexibly recruit brain regions to match given task demands. This may result in greater reliance on neuroanatomy that is associated with visual, spatial, and motoric processing rather than verbal strategies. The authors speculate that this impaired flexibility in recruiting brain regions and associated strategies limits adaptation to new cognitive demands as they present and may require more effortful processing.     

Is neck circumference measurement an indicator for abdominal obesity? A pilot study on Turkish Adults

Background

Neck circumference (NC) measurement is one of the simple screening measurements which can be used as an index of upper body fat distribution to identify obesity.

Objectives

The aim of this study was to determine the relationship between neck circumferences and obesity.

Methods

A total 411 volunteer adults participated in this study (174 men, 237 women). A questionnaire which consisted of anthropometric measurements and demographic features was used. Patients with NC ≥37 cm for men and ≥34 cm for women require evaluation of overweight status.

Results

The percentages of the men and women with BMI ≥ 25kg/m² were 55.2% and 27.0% respectively and with high neck circumferences were 85.1% and 38.8%, respectively. The percentages of the men and women with high waist circumference were 31.6% and 79.3%, respectively. In both gender there were positive significant correlations between neck circumference, body weight (men, r=0.576; women, r=0.702; p=0.000), waist circumferences (men, r=0.593; women r=0.667; p=0.000), hip circumferences (men, r=0.568; women, r=0.617; p=0.000) and BMI (men, r=0.587; women, r=0.688; p=0.000).

Conclusions

This study indicates that NC was associated with body weight, BMI, waist and hip circumferences and waist/hip ratio for men and women. A significant association was found between NC and conventional overweight and obesity indexes. NC was associated with waist/hip ratio for men and women.     

Th1–Th2 Interaction: Is More Complex than a See‐saw?

Infections, such as tuberculosis, measles and diphtheria, may decrease the risk of developing atopic allergic disorders. Patients with pulmonary TB having similar allergic skin prick test sensitivity as healthy controls but unable to show vigorous atopic phenotype in their healthy period might be a sign for Th1-Th2 immune interaction.     

Is there a role for atrial peptides in the labyrinthine “disease”?

The important role of atrial natriuretic peptides (ANP) in regulating blood pressure and changing vascular permeability has been widely studied and assessed during the last ten years. Considering the characteristics of this mechanism, which is responsible for a hypotensive and hypovolemic effect, and the possible role of hypotension associated with a default of autoregulatory sympathetic reactions in inner ear unexplained disorders, it seems reasonable to hypothesize a possible involvement of ANP system in the genesis of such disorders. As a matter of fact, the presence of specific receptors for ANP in the inner ear has been widely reported in studies concerning both rat and human inner ear, although their precise role in the labyrinthine homeostasis has not been satisfactory explained until now. Some aspects concerning vascular and fluid regulation of the inner ear under different conditions still remain not totally clear, and consequently a detailed explanation to the possible mechanism causing inner ear disorders of functional origin is lacking; from this point of view, an investigation on the serum level of ANP in subjects with labyrinthine affections of uncertain origin could be of some utility in contributing to assess the role of this system in the inner ear fluid regulation and in the inner ear perfusion and to investigate on the possible influence of an abnormal ANP release in some kind of inner ear damage.     

Is there a difference in clinical efficacy of bright light therapy for different types of depression? A pilot study

Background

There is growing interest in the possible applications of Bright Light Therapy (BLT). BLT might be a valid alternative or add-on treatment for many other psychiatric disorders beyond seasonal affective disorder. This pilot study aims to examine whether the efficacy of Bright Light Therapy (BLT) is similar for different subtypes of mood disorders.

Methods

Participants were 48 newly admitted outpatients with major depressive disorder with either melancholic features (n=20) or atypical features (n=28). Morning BLT was administered daily for 30 min at 5.000–10.000 lx on working days for up to 3 consecutive weeks.

Results

Participants' depressive symptoms improved significantly after BLT (p<.05, d=−.53). The effects of BLT remained stable across a 4 week follow-up. There were no significant differences in efficacy of BLT between groups (p>.05). No effect of seasonality on the improvement in depressive symptoms after BLT was found, (p=.781).

Limitations

The study had a small sample size and lacked a control condition.

Conclusions

This pilot study provides preliminary evidence that BLT could be a promising treatment for depression, regardless of the melancholic or atypical character of the depressive symptoms.     

Resection margins and R1 rates in pancreatic cancer – are we there yet?

The prognosis of pancreatic cancer is poor, even for those patients who undergo surgical resection. The rate of local recurrence is high, despite the fact that in most series complete ('R0') resection is reported to be achieved in the majority of patients. The discrepancy between pathological assessment and clinical outcome indicates that microscopic margin involvement (R1) is frequently underreported, and potential causes for this are discussed in this review. Special emphasis is given to the variation that exists between currently used dissection techniques and their impact on the assessment of the resection margins in pancreatoduodenectomy specimens.     

Increase of asthma in adults in northern Finland?– a report from the FinEsS study

BACKGROUND: According to previous studies, the prevalence of asthma has been lower in Finland than in other Nordic countries. In the present study, we assessed the prevalence of asthma and respiratory symptoms in northern Finland and calculated risk factors for these conditions. METHODS: In November 1995, 7937 randomly selected subjects, 20-69 years of age, in northern Finland were invited to participate in a postal questionnaire survey. Complete answers were received from 6633 subjects (83.6%). RESULTS: Asthma diagnosed by a physician was reported by 6.0%, while 6.3% were using asthma medicines. Asthma was most common in young adults and the elderly. The prevalence of wheezing during the previous 12 months was reported by 19.7%, while wheezing with shortness of breath apart form colds during the previous 12 months was reported by 7.1%. Only small differences between the sexes were found in prevalence of asthma and respiratory symptoms. All symptoms were strongly smoking-dependent. Sixty-three percent of men and 42% of women were current or ex-smokers. Family history of obstructive airway disease was the strongest risk factor for asthma (OR 2.9), while increasing age, smoking, and family history of obstructive airway disease were the most important risk factors for frequent wheeze. CONCLUSIONS: The results indicate that the prevalence of asthma and symptoms associated with asthma in adults in northern Finland is now similar to that observed in Sweden and the other Nordic countries.