Impact on child and parent anxiety level of a teddy bear-scale mock magnetic resonance scanner.

BACKGROUND: Pediatric magnetic resonance imaging (MRI) can be stressful. Mock MR scanners have been proven to be effective in avoiding the use of general anesthesia. OBJECTIVES: We prospectively evaluated the impact of a teddy bear-scale model of a mock MR scanner on the anxiety experienced by parents and their children during MRI without general anesthesia . MATERIALS AND METHODS: A 1-year prospective study before and after the installation of a mock scanner in a Pediatric Radiology Department of a university hospital. Anxiety levels were self-estimated by children ages 4 to 16 years and by the parents with a visual analogue scale (from 0, completely relaxed, to 100, extremely stressed) at three moments: in the waiting room, in the preparation room after an explanation by the MRI technologists, and at the issue of the MR acquisition images. Two groups were tested: one with a mock MR scanner, the other without. Analysis of variance (ANOVA) and Fisher exact tests were performed. Motion artifacts were studied. RESULTS: Ninety-one children and their parents were included. The median age was 8 years (standard deviation [SD]=2). In the post mock period, the ambiance of the preparation room was considered by children as significantly more relaxing in 50% vs. 20% (P=0.004) and the anxiety level of children was significantly lower after the explanation, particularly in girls, but unchanged for their parents. The anxiety levels at the end of the examination were significantly lower for parents. The motion artifacts rate was lower (1.7% vs. 4.7%, P=0.04). CONCLUSION: A mock scanner was an efficient tool to improve efficiency of the explanation and to decrease anxiety in children and motion artifacts in pediatric MRI.

Association Between Tetralogy of Fallot and Tracheobronchial Branching Abnormalities: A New Clue for Pathogenesis?

BACKGROUND: In our practice, we noticed an increased frequency of tracheobronchial branching abnormalities (TBAs) in patients with tetralogy of Fallot (ToF). This study aimed to determine whether an association exists between congenital TBAs and ToF with or without pulmonary atresia. METHODS AND RESULTS: The frequency of TBAs on chest computed tomography was assessed in 55 patients with ToF without pulmonary atresia, 34 patients with ToF with pulmonary arteria, and 100 control patients. We then looked for a possible association between TBAs and pulmonary artery branch hypoplasia, the presence of major aortopulmonary collateral arteries, and the presence of the chromosome 22q11 deletion. TBAs were significantly more frequent in patients with ToF with or without pulmonary atresia than in the control group (any TBAs, 21% versus 2% [P<0.001]; bronchial situs anomalies, 6% versus 0% [P=0.002]; right tracheal bronchus, 4% versus 0% [P=0.04]; left eparterial bronchus, 8% versus 0% [P=0.005]); and tended to be more frequent in those with ToF without pulmonary atresia than in those with ToF with pulmonary atresia (any TBAs, 27% versus 12% [P=0.11]; left eparterial bronchus, 13% versus 0% [P=0.04]). TBAs were readily multiple (8 patients of 19 with TBA) and concerned essentially the upper lobes. TBAs were not associated with pulmonary branch hypoplasia, major aortopulmonary collateral arteries, or the chromosome 22q11 deletion. CONCLUSIONS: We demonstrated a significantly increased frequency of tracheobronchial abnormalities in patients with ToF with or without pulmonary atresia compared with a control group. These results suggest an interaction between abnormalities in conotruncal septation and tracheobronchial branching and may provide a new clue to the pathogenesis of conotruncal heart diseases.

Endocrine, metabolic, and behavioral effects of and recovery from acute stress in a free-ranging bird.

Acute stress in vertebrates generally stimulates the hypothalamo-pituitary-adrenal axis and is often associated with multiple metabolic changes, such as increased gluconeogenesis, and with behavioral alterations. Little information is available, especially in free-ranging organisms, on the duration of these reversible effects once animals are no longer exposed to the stressor. To investigate this question, we exposed free-ranging adult male Rufous-winged Sparrows, Peucaea carpalis, in breeding condition to a standard protocol consisting of a social challenge (conspecific song playback) followed with capture and restraint for 30min, after which birds were released on site. Capture and restraint increased plasma corticosterone (CORT) and decreased plasma testosterone (T), glucose (GLU), and uric acid (UA). In birds that we recaptured the next day after exposure to conspecific song playback, plasma CORT and UA levels no longer differed from levels immediately after capture the preceding day. However, plasma T was similar to that measured after stress exposure the preceding day, and plasma GLU was markedly elevated. Thus, exposure to social challenge and acute stress resulted in persistent (⩾24h) parameter-specific effects. In recaptured sparrows, the territorial aggressive response to conspecific song playback, as measured by song rate and the number of flights over the song-broadcasting speakers, did not, however, differ between the first capture and the recapture, suggesting no proximate functional association between plasma T and conspecific territorial aggression. The study is the first in free-ranging birds to report the endocrine, metabolic, and behavioral recovery from the effects of combined social challenge and acute stress.

The seasonal glucocorticoid response of male Rufous-winged Sparrows to acute stress correlates with changes in plasma uric acid, but neither glucose nor testosterone.

We sought to clarify functional relationships between baseline and acute stress-induced changes in plasma levels of the stress hormone corticosterone (CORT) and the reproductive hormone testosterone (T), and those of two main metabolites, uric acid (UA) and glucose (GLU). Acute stress in vertebrates generally stimulates the secretion of glucocorticoids, which in birds is primarily CORT. This stimulation is thought to promote behavioral and metabolic changes, including increased glycemia. However, limited information in free-ranging birds supports the view that acutely elevated plasma CORT stimulates glycemia. Acute stress also often decreases the secretion of reproductive hormones (e.g., T in males), but the role of CORT in this decrease and the contribution of T to the regulation of plasma GLU remain poorly understood. We measured initial (pre-stress) and acute stress-induced plasma CORT and T as well as GLU in adult male Rufous-winged Sparrows, Peucaea carpalis, sampled during the pre-breeding, breeding, post-breeding molt, and non-breeding stages. Stress increased plasma CORT and the magnitude of this increase did not differ across life history stages. The stress-induced elevation of plasma CORT was consistently associated with decreased plasma UA, suggesting a role for CORT in the regulation of plasma UA during stress. During stress plasma GLU either increased (pre-breeding), did not change (breeding), or decreased (molt and non-breeding), and plasma T either decreased (pre-breeding and breeding) or did not change (molt and non-breeding). These data provide only partial support to the hypothesis that CORT secretion during acute stress exerts a hyperglycemic action or is responsible for the observed decrease in plasma T taking place at certain life history stages. They also do not support the hypothesis that rapid changes in plasma T influence glycemia.

Tracheobronchial Branching Abnormalities: Lobe-based Classification Scheme.

Boyden's nomenclature, which was based on postmortem specimens and published in 1955 prior to the advent of computed tomography (CT), is commonly used to describe the normal segmental bronchial anatomy and various abnormalities. However, several additional anomalies have been recognized since that time, and there is some confusion over the names used to describe these anomalies. Several congenital branching anomalies affecting the trachea, main bronchi, and intermediate bronchus have been reported, all of which can be recognized at chest CT but are often overlooked. These anomalies, which probably occur early in fetal life, can be either supernumerary, with defects occurring at 29-30 days gestation, or displaced, with defects occurring later. Tracheobronchial positional anomalies are often associated with other congenital abnormalities but may be isolated. They often are asymptomatic but can be responsible for pulmonary symptoms such as dyspnea, recurrent pneumonia, and hemoptysis. It is essential that these anomalies are recognized prior to lung resection to avoid complications, especially when video-assisted thoracoscopic surgery is performed. In addition, bronchoscopists should be aware of these anomalies before performing diagnostic or therapeutic bronchoscopic procedures. Awareness of a few key bronchial anatomic principles and use of a lobe-based classification scheme will facilitate recognition of tracheobronchial positional anomalies.

Food restriction negatively affects multiple levels of the reproductive axis in male house finches, Haemorhous mexicanus.

Nutrition influences reproductive functions across vertebrates, but the effects of food availability on the functioning of the hypothalamic-pituitary-gonadal (HPG) axis in wild birds and the mechanisms mediating these effects remain unclear. We investigated the influence of chronic food restriction on the HPG axis of photostimulated house finches, Haemorhous mexicanus. Food-restricted birds had underdeveloped testes with smaller seminiferous tubules than ad libitum-fed birds. Baseline plasma testosterone increased in response to photostimulation in ad libitum-fed but not in food-restricted birds. Food availability did not, however, affect the plasma testosterone increase resulting from a gonadotropin-releasing hormone-I (GnRH) or a luteinizing hormone (LH) challenge. The number of hypothalamic GnRH immunoreactive (ir) but not proGnRH-ir perikarya was higher in food-restricted than in ad libitum-fed finches, suggesting inhibited secretion of GnRH. Hypothalamic gonadotropin-inhibitory hormone (GnIH)-ir and neuropeptide Y (NPY)-ir were not affected by food availability. Plasma corticosterone (CORT) was also not affected by food availability, indicating that the observed HPG axis inhibition did not result from increased activity of the hypothalamic-pituitary-adrenal (HPA) axis. This study is among the first to examine multilevel functional changes in the HPG axis in response to food restriction in a wild bird. The results indicate that food availability affects both hypothalamic and gonadal function, but further investigations are needed to clarify the mechanisms by which nutritional signals mediate these effects.