Educational paper

The emergency room (ER) represents the main system entry for crises-based health care visits. It is estimated that 2% to 10% of children visiting the ER are victims of child abuse and neglect (CAN). Therefore, ER personnel may be the first hospital contact and opportunity for CAN victims to be recognised. Early diagnosis of CAN is important, as without early identification and intervention, about one in three children will suffer subsequent abuse. This educational paper provides the reader with an up-to-date and in-depth overview of the current screening methods for CAN at the ER. Conclusion: We believe that a combined approach, using a checklist with risk factors for CAN, a structured clinical assessment and inspection of the undressed patient (called 'top-toe' inspection) and a system of standard referral of all children from parents who attend the ER because of alcohol or drugs intoxication, severe psychiatric disorders or with injuries due to intimate partner violence, is the most promising procedure for the early diagnosis of CAN in the ER setting.     

Improving the cell distribution in collagen-coated poly-caprolactone knittings

Adequate cellular in-growth into biomaterials is one of the fundamental requirements of scaffolds used in regenerative medicine. Type I collagen is the most commonly used material for soft tissue engineering, because it is nonimmunogenic and a highly porous network for cellular support can be produced. However, in general, adequate cell in-growth and cell seeding has been suboptimal. In this study we prepared collagen scaffolds of different collagen densities and investigated the cellular distribution. We also prepared a hybrid polymer-collagen scaffold to achieve an optimal cellular distribution as well as sufficient mechanical strength. Collagen scaffolds [ranging from 0.3% to 0.8% (w/v)] with and without a mechanically stable polymer knitting [poly-caprolactone (PCL)] were prepared. The porous structure of collagen scaffolds was characterized using scanning electron microscopy and hematoxylin-eosin staining. The mechanical strength of hybrid scaffolds (collagen with or without PCL) was determined using tensile strength analysis. Cellular in-growth and interconnectivity were evaluated using fluorescent bead distribution and human bladder smooth muscle cells and human urothelium seeding. The lower density collagen scaffolds showed remarkably deeper cellular penetration and by combining it with PCL knitting the tensile strength was enhanced. This study indicated that a hybrid scaffold prepared from 0.4% collagen strengthened with knitting achieved the best cellular distribution.     

Screening for hearing loss versus parental concern regarding hearing problems: Subsequent referral and treatment for otitis media in the Netherlands

Abstract Objective. The present study investigates whether general practitioner (GP) consultation initiated by failing the population hearing screening at age nine months or GP consultation because of parental concern over ear/hearing problems was more important in deciding on referral and/or surgical treatment of otitis media (OM). Design. A questionnaire covering the history between birth and 21 months of age was used to obtain information on referral after failing the hearing screening, GP consultations for ear/hearing problems, and subsequent referral to a specialist and possible surgical treatment at an ENT department. Setting. The province of Limburg, the Netherlands. Subjects. Healthy infants invited for the hearing screening at age nine months, who responded in an earlier study called PEPPER (Persistent Ear Problems, Providing Evidence for Referral, response rate 58%). Main outcome measures. The odds of a child being surgically treated for OM. Results. The response rate for the present questionnaire was 72%. Of all children tested, 3.9% failed the hearing screening and were referred to their GP. Of all 2619 children in this study, 18.6% visited their GP with ear/hearing problems. Children failing the hearing screening without GP consultation for ear/hearing problems were significantly more often treated surgically for OM than children passing the hearing screening but with GP consultation for ear/hearing problems. Conclusion. Objectified hearing loss, i.e. failing the hearing screening, was important in the decision for surgical treatment in infants in the Netherlands.     

Diagnostic imaging advances in murine models of colitis

Inflammatory bowel diseases(IBD) such as Crohn's disease and ulcerative colitis are chronic-remittent inflammatory disorders of the gastrointestinal tract still evoking challenging clinical diagnostic and therapeutic situations. Murine models of experimental colitis are a vital component of research into human IBD concerning questions of its complex pathogenesis or the evaluation of potential new drugs. To monitor the course of colitis, to the present day, classical parameters like histological tissue alterations or analysis of mucosal cytokine/chemokine expression often require euthanasia of animals. Recent advances mean revolutionary noninvasive imaging techniques for in vivo murine colitis diagnostics are increasingly available. These novel and emerging imaging techniques not only allow direct visualization of intestinal inflammation, but also enable molecular imaging and targeting of specific alterations of the inflamed murine mucosa. For the first time, in vivo imaging techniques allow for longitudinal examinations and evaluation of intra-individual therapeutic response. This review discusses the latest developments in the different fields of ultrasound, molecularly targeted contrast agent ultrasound, fluorescence endoscopy, confocal laser endomicroscopy as well as tomographic imaging with magnetic resonance imaging, computed tomography and fluorescence-mediated tomography,discussing their individual limitations and potential future diagnostic applications in the management of human patients with IBD.     

Effect of training on the incidence of nerve damage in thyroid surgery

BACKGROUND: In thyroid surgery early postoperative recurrent laryngeal nerve (RLN) dysfunction offers a sensitive measure of the quality of the operation. The aim of this study was to analyse the effect of training in thyroid surgery on the rate of early functional disturbances of the RLN after thyroid resection. METHODS: In 617 patients (median age 48 years, female to male ratio 2.8:1) who underwent unilateral or bilateral thyroid resection, 1059 RLNs were subjected to operative risk. Laryngoscopy was performed before and after operation. The 45 surgeons were divided into three groups: group 1, specialist thyroid surgeons; group 2, experienced surgeons; and group 3, residents. Personal gain of experience was defined by the preceding number of thyroid operations. Within each group the complication profile was determined by adding the personal complication profiles of each surgeon. RESULTS: The complication rates were low during surgical residency (group 3). In group 2 complication rates increased up to the 50th operation. Group 1 showed the expected exponential decrease to under per cent after another 130 operations. CONCLUSION: Complication rates are affected considerably by the extent of surgical experience in a non-linear and complex logarithmic manner, starting with low rates in the beginner group, peaking after further experience and then decreasing exponentially.     

Severe distortion in the representation of foveal visual image locations in short-term memory

The foveal visual image region provides the human visual system with the highest acuity. However, it is unclear whether such a high fidelity representational advantage is maintained when foveal image locations are committed to short-term memory. Here, we describe a paradoxically large distortion in foveal target location recall by humans. We briefly presented small, but high contrast, points of light at eccentricities ranging from 0.1 to 12°, while subjects maintained their line of sight on a stable target. After a brief memory period, the subjects indicated the remembered target locations via computer controlled cursors. The biggest localization errors, in terms of both directional deviations and amplitude percentage overshoots or undershoots, occurred for the most foveal targets, and such distortions were still present, albeit with qualitatively different patterns, when subjects shifted their gaze to indicate the remembered target locations. Foveal visual images are severely distorted in short-term memory.

The representation of visual spatial locations in short-term memory has been one of the most classic means for studying the neural mechanisms of cognitive control in modern-day systems neuroscience (1–6). Experimentally, reporting a remembered target location with a saccadic eye movement has proven extremely useful in demonstrating how different cortical and subcortical brain regions may maintain a memory trace of visual targets (7), and it has also been equally important for oculomotor control studies in dissociating sensory and motor responses (8–11).One mechanism for short-term memory maintenance in multiple brain areas is the persistence of neural activity associated with remembered stimulus locations, even in the absence of sensory drive (7, 12). Such persistence, with temporal drift, can help explain a variety of distortions in memory-based task performance, for example, as a function of how long a location needs to be maintained in short-term memory (12). In addition, such persistence can reveal certain systematic biases with respect to whether stimuli occupy a single visual quadrant or multiple visual quadrants (13), which in turn enables linking visual field asymmetries in perception to representations of remembered target locations. For example, visual performance along the horizontal and vertical retinotopic meridians is different (14–16), and this difference is maintained in tasks involving short-term memory (17). The fact that such visual meridian effects may be related to tissue magnification in visual cortical areas (18–20) might then suggest that other known distortions in short-term memory tasks, such as foveal biases in remembering peripheral target locations (21–23), may also be related to how visual space is represented in topographic maps.If remembering visual target locations depends on both how visual space is topographically represented as well as on how memory information is neurally maintained, then an important remaining open question is whether foveal visual locations are recalled veridically or not, given the normally very high acuity nature of foveal vision in humans. Here, we investigated this question and found that remembering a foveal visual location as near to the line of sight as 0.1° (6 min arc) is subject to severe distortion, even after very short memory delay intervals. This paradoxical foveal distortion in visual short-term memory emerges with or without a constant landmark being available during the response phase of the task, and, perhaps most importantly, it is also qualitatively different depending on whether the remembered location is reported with an eye movement response or with another response modality.