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Background: Magnetic resonance neurography (MRN) is an imaging method by which nerves can be selectively highlighted. Using commercial software, the authors explored a variety of approaches to develop a three-dimensional volume-rendered MRN image of the entire brachial plexus and used it to evaluate the accuracy of infraclavicular block approaches.

Methods: With institutional review board approval, MRN of the brachial plexus was performed in 10 volunteer subjects. MRN imaging was performed on a GE 1.5-tesla magnetic resonance scanner (General Electric Healthcare Technologies, Waukesha, WI) using a phased array torso coil. Coronal STIR and T1 oblique sagittal sequences of the brachial plexus were obtained. Multiple software programs were explored for enhanced display and manipulation of the composite magnetic resonance images. The authors developed a frontal slab composite approach that allows single-frame reconstruction of a three-dimensional volume-rendered image of the entire brachial plexus. Automatic segmentation was supplemented by manual segmentation in nearly all cases. For each of three infraclavicular approaches (posteriorly directed needle below midclavicle, infracoracoid, or caudomedial to coracoid), the targeting error was measured as the distance from the MRN plexus midpoint to the approach-targeted site.

Results: Composite frontal slabs (coronal views), which are single-frame three-dimensional volume renderings from image-enhanced two-dimensional frontal view projections of the underlying coronal slices, were created. The targeting errors (mean +/- SD) for the approaches-midclavicle, infracoracoid, caudomedial to coracoid-were 0.43 +/- 0.67, 0.99 +/- 1.22, and 0.65 +/- 1.14 cm, respectively.  相似文献   

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Seven days or more of inadequate oral intake (IOI) inevitably results in a deterioration in nutritional status. Despite this well-known fact, little information is available as to the frequency with which such periods of IOI occur in clinical practice. This study results from an audit of IOI in a gastroenterological unit over a 6-month period. The results demonstrate that 17% of patients sustained significant periods of IOI of 7 days or longer. This has important implications with regard to the provision of adjuvant nutritional support.  相似文献   
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Abstract Factors influencing the remarkable growth of home health care include increased elderly population, decreased average length of hospital stay, and technological advancements that reduce the need for hospitalization. Societal changes have prompted increasing concern about personal risk to home care providers. The purpose of this pilot study was to: 1) ascertain factors related to perception of risk by home health care administrators and staff and to identify strategies used by home health care administrators to reduce risk to staff; and 2) determine whether quality of care is affected when home-visit situations present risk. A convenience sample of 36 home health care administrators and 62 staff was surveyed about risks and measures provided by the home health care agency to minimize risk. Factors associated with risk are geographic location, high incidence of crime, inappropriate patient or caregiver behavior, infectious diseases, and evening assignments. Strategies used to minimize risk include safety programs, preplanning of visits, personal protective equipment, escorts, and buddy systems. Perceived ability to refuse high-risk assignments, however, is questionable, as 66% of the staff stated that they leave a situation "as soon as possible." These findings will be used to strengthen inservice programs and to provide a basis for future studies.  相似文献   
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A majority of a cohort of 62 children and adolescents who had been hospitalized in a state psychiatric facility was found to have received less restrictive services such as outpatient mental health services prior to their index admission. Also, a number had been involved with the juvenile justice system and almost two-thirds had been placed out-of-home. Ninety percent had at least one prior psychiatric hospitalization. Just over half of the cohort received case management and individual counseling post release. About a third received family counseling, and a few received other types of services. At least a third were rehospitalized within a year of release. Although 90% of the cohort received some type of service post release, a higher proportion of non service receivers were rehospitalized than service receivers. Even those who received services had a high rate of rehospitalization. These findings raise questions as to the appropriateness of service provision during and following hospitalization.This study was funded by a grant from the Office of Program Evaluation and Research, Ohio Department of Mental Health.  相似文献   
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The purpose of this pilot study was to determine the effects of the addition of coping skills training for obese multiethnic parents whose overweight children were attending a weight management program. At 6 months, parents in the experimental group had significantly lower body mass index (BMI) and body fat percentage (BFP) and higher numbers of pedometer steps compared with those in the control group. Parents in the experimental group also demonstrated significant improvement in interpersonal relationships, behavior control, and stress management compared with those in the control group. Children in the experimental group demonstrated trends toward decreased BMI and BFP and increased pedometer steps.  相似文献   
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