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Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
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We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.  相似文献   
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The clinical, radiologic, and histopathologic findings of a case of bilateral dacryops is reported in a 49-year-old man. The patient presented with cystic masses located in superior lateral orbits and underwent bilateral excisions of these without any postoperative complications.  相似文献   
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There are many potential sources of variability in speech production, particularly in individuals with dysarthria. The degree and time course of stabilization of the speech production system during recovery from a neurological insult is not constant across individuals. Another source of variability in speech production is speaking rate. Although individuals with no neurological impairments typically show increased variability at reduced speaking rates, this phenomenon has not been explored extensively in individuals with dysarthria. Because rate control strategies are commonly used in dysarthria treatment, it is of clinical importance to know if individuals with dysarthria produce less variable speech with rate reduction. Six individuals with mild dysarthria, 6 with moderate-to-severe dysarthria, and 6 matched normal controls repeated an utterance in four speaking rate conditions: habitual, fast, breaks between words, and stretched. Data were analyzed using the spatiotemporal index (STI), a composite measure of spatial and temporal variability across token repetitions. The normal controls consistently demonstrated the least variability, regardless of rate condition. Both groups with dysarthria were the least variable in the stretched condition and the most variable in the fast condition. The STI values of the group with moderate-to-severe dysarthria were significantly different from both the individuals with mild dysarthria and the normal controls. There were no significant differences between the group with mild dysarthria and the normal controls. In general, slowing the speaking rate in individuals with dysarthria reduces spatiotemporal variability; however, the effect of reduced spatiotemporal variability on intelligibility requires further investigation.  相似文献   
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Chemically distinct rat olivocochlear neurons.   总被引:6,自引:0,他引:6  
We have produced a neurochemical map of the cell bodies of origin of the cochlear efferent terminals in rat by combining glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), or calcitonin gene-related peptide (CGRP) immunocytochemistry with retrograde transport of horseradish peroxidase. The locations of cochlear efferent cell bodies are in general agreement with the medial and lateral systems described by White and Warr (J. Comp. Neurol. 219:203-214, 1983) with some minor modifications. The lateral system consists of at least two pools of chemically distinct neurons located within the lateral superior olive (LSO) ipsilateral to the injected cochlea. One pool immunostains with an antibody to GAD while the other immunostains with antibodies to ChAT and to CGRP. The medial efferent system consists of periolivary neurons that are almost exclusively large and ChAT-positive but CGRP-negative. They are located both ipsilateral and contralateral to the cochlea they project to. There are a few GAD-positive small neurons in the medioventral and rostral periolivary regions that project ipsilaterally, but these may prove tobe ectopic neurons. The ipsilateral lateroventral periolivary region (LVPO) contains some efferent neurons, all of which are ChAT-positive but CGRP-negative. Additional cochlear efferent neurons, some of which are ChAT-positive and others GAD-positive, are present within and immediately dorsal to the fiber capsule surrounding the medial limb, and to a lesser extent the lateral limb, of the ipsilateral LSO. Not all GAD-positive or ChAT-positive olivary cells project to the cochlea. We have complemented the results in the brainstem by demonstrating two immunocytochemically distinct populations of efferent terminals in the cochlea simultaneously, one CGRP-positive and the other GAD-positive. Approximately equal numbers of boutons immunoreactive for both markers are present beneath inner hair cells throughout the entire length of the cochlea. Surprisingly high numbers of GAD-positive and CGRP-positive boutons are also present on outer hair cells, with each class having its spatially and morphologically distinct features. The lack of CGRP-positive periolivary cells that are retrogradely labeled by cochlear injections of HRP suggests that the lateral olivocochlear system sends projections to outer hair cells. Our results raise questions about species differences in the organization of targets of the lateral and medial olivocochlear systems.  相似文献   
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