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1.
Eur Radiol ; 24(1): 102-11, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23995879

RESUMO

OBJECTIVES: To assess the benefit and limits of iterative reconstruction of paediatric chest and abdominal computed tomography (CT). METHODS: The study compared adaptive statistical iterative reconstruction (ASIR) with filtered back projection (FBP) on 64-channel MDCT. A phantom study was first performed using variable tube potential, tube current and ASIR settings. The assessed image quality indices were the signal-to-noise ratio (SNR), the noise power spectrum, low contrast detectability (LCD) and spatial resolution. A clinical retrospective study of 26 children (M:F = 14/12, mean age: 4 years, range: 1-9 years) was secondarily performed allowing comparison of 18 chest and 14 abdominal CT pairs, one with a routine CT dose and FBP reconstruction, and the other with 30 % lower dose and 40 % ASIR reconstruction. Two radiologists independently compared the images for overall image quality, noise, sharpness and artefacts, and measured image noise. RESULTS: The phantom study demonstrated a significant increase in SNR without impairment of the LCD or spatial resolution, except for tube current values below 30-50 mA. On clinical images, no significant difference was observed between FBP and reduced dose ASIR images. CONCLUSION: Iterative reconstruction allows at least 30 % dose reduction in paediatric chest and abdominal CT, without impairment of image quality. KEY POINTS: • Iterative reconstruction helps lower radiation exposure levels in children undergoing CT. • Adaptive statistical iterative reconstruction (ASIR) significantly increases SNR without impairing spatial resolution. • For abdomen and chest CT, ASIR allows at least a 30 % dose reduction.


Assuntos
Imagens de Fantasmas , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/normas , Radiografia Torácica/normas , Tomografia Computadorizada por Raios X/normas , Artefatos , Criança , Pré-Escolar , Interpretação Estatística de Dados , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal/métodos , Radiografia Torácica/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos
2.
Work ; 11(1): 35-42, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-24441481

RESUMO

In the absence of literature on upper extremity (UE) injury prevention programs, this study gathered data on educational programs currently available to enhance future programming. A telephone survey with written follow-up for verification and accuracy was used to collect descriptive data about the expected outcomes, educational content, program parameters and evaluation methods for UE injury prevention programs offered by nationally based companies. Six companies participated in the survey. Changes in employee behaviors and lifestyles were the most frequently expected outcomes. The educational content consistently contained information on anatomy and physiology and frequently contained risk factor information. Lectures were the primary form of presentation, with limited opportunity for practice or problem solving. Two-hour programs were typically offered on site for groups of 20-25 participants at charges ranging from $100 to $300 per hour. The inconsistencies in current programming and insufficient definition of efficacy measures provide little guidance on how UE prevention programs should be designed.

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