Valores típicos de dosis para tomografía computada de cerebro en pacientes adultos / Typical dose values for brain computed tomography in adult patients

Resumen: Debido al aumento en el uso de la Tomografía Computada (TC), y en consecuencia, la probabilidad de generar un incremento progresivo de la dosis recibida por los paciente y su relación en el potencial riesgo de los efectos de las radiaciones ionizantes, es importante implementar el uso de niveles de referencia diagnóstico (DRLs) en TC, como herramienta fundamental dentro de un programa de control de calidad que permita la evaluación y optimización de las dosis entregadas a los pacientes según la tarea clínica deseada. Con el objetivo de establecer valores típicos de dosis en TC de cerebro en Clínica Bupa Reñaca, se estudió una muestra de 73 informes dosimétricos generados en un equipo TC Toshiba Aquilion 64, en términos de indicadores de dosis para TC: Índice de dosis en TC por volumen (CTDIvol) y Producto dosis longitud (DLP). Con los datos obtenidos, se estimó el valor del percentil 50 (p50) para cada indicador de dosis, y se determinaron los valores típicos de dosis en cada grupo estudiado según sexo, edad e indicación clínica. Se logró definir y establecer una metodología que permitió la obtención de los valores típicos de dosis para TC de cerebro, optimizando las dosis sin producir una disminución en la calidad de la imagen necesaria para nuestro propósito clínico.

Abstract: Due to the increase in the use of Computed Tomography (CT), and consequently, the probability of generating a progressive increase in the dose received by the patient and its relationship in the potential risk of the effects of ionizing radiation, it is important to implement the use of diagnostic reference levels (DRLs) in CT, as a fundamental tool within a quality control program that allows the evaluation and optimization of the doses delivered to patients according to the desired clinical task. In order to establish typical dose values in brain CT at Bupa Reñaca Clinic, a sample of 73 dosimetric reports generated on a Toshiba Aquilion 64 CT unit was studied, in terms of dose indicators for CT: Dose rate on CT by volume (CTDIvol) and Dose Length Product (DLP). With the data obtained, the value of the 50th percentile (p50) for each dose indicator was estimated, and typical dose values were determined in each group studied according to sex, age and clinical indication. It was possible to define and establish a methodology that allowed obtaining typical dose values for brain CT, optimizing the doses without producing a decrease in the image quality necessary for our clinical purpose.

Imaging in idiopathic pulmonary fibrosis: diagnosis and mimics

Idiopathic pulmonary fibrosis is a chronic disease of unknown etiology that usually has a progressive course and is commonly associated with a poor prognosis. The main symptoms of idiopathic pulmonary fibrosis, including progressive dyspnea and dry cough, are often nonspecific. Chest high-resolution computed tomography is the primary modality used in the initial assessment of patients with suspected idiopathic pulmonary fibrosis and may have considerable influence on subsequent management decisions. The main role of computed tomography is to distinguish chronic fibrosing lung diseases with a usual interstitial pneumonia pattern from those presenting with a non-usual interstitial pneumonia pattern, suggesting an alternative diagnosis when possible. A usual interstitial pneumonia pattern on chest tomography is characterized by the presence subpleural and basal predominance, reticular abnormality honeycombing with or without traction bronchiectasis, and the absence of features suggestive of an alternative diagnosis. Idiopathic pulmonary fibrosis can be diagnosed according to clinical and radiological criteria in approximately 66.6% of cases. Confirmation of an idiopathic pulmonary fibrosis diagnosis is challenging, requiring the exclusion of pulmonary fibroses with known causes, such as asbestosis, connective tissue diseases, drug exposure, chronic hypersensitivity pneumonitis, and other forms of idiopathic interstitial pneumonitis. The histopathological hallmark of usual interstitial pneumonia is a heterogeneous appearance, characterized by areas of fibrosis with scarring and honeycombing alternating with areas of less affected or normal parenchyma. The aim of this article was to review the clinical, radiological, and pathological features of idiopathic pulmonary fibrosis and of diseases that might mimic idiopathic pulmonary fibrosis presentation.

Corrección de índice de dosis en tomografía computarizada por parámetro de diámetro efectivo según reporte 204 de la Asociación Americana de Físicos Médicos / Computed tomography dose index correction by effective diameter according to report 204 by the American Association of Physicists in Medicine

Abstract. In order to have a more accurate estimation of the dose delivered for computed tomography (CT) studies, and given that the current dose estimates do not include the size of the patient, a retrospective study was conducted on a sample of 388 patients from the radiology department of a general hospital, to make a better assessment of the dose delivered for CT scans of the chest, abdomen and pelvis in adult and paediatric patients. A comparison was made between the volume computed tomography dose index (CTDIvol) delivered by the scanner and CTDIvol value corrected by the incorporation of the effective patient diameter according to the report 204 of the American Association of Physicists in Medicine (AAPM). It was found that the values of CTDIvol vary in all cases when the patient size parameter is included, with this variation being greater as sizes go to extremes.

Resumen. Con el objetivo de tener una estimación de dosis más exacta entregada por los estudios de tomografía computarizada (TC) y dado que los estimadores de dosis actuales no incluyen el tamaño del paciente en la estimación, se realizó un estudio retrospectivo en una muestra de 388 pacientes de un servicio de radiología de un hospital general, para calcular las dosis entregadas en exámenes de TC de tórax, abdomen y pelvis en pacientes adultos y pediátricos. Se elaboró y realizó una comparación entre el índice de dosis de TC (CTDI VOL) entregado por el equipo y el CTDI VOL corregido mediante la incorporación del parámetro del diámetro efectivo del paciente según el reporte 204 de la Asociación Americana de Físicos Médicos (AAPM). Se pudo comprobar que los valores de CTDI VOL varían en la totalidad de los casos al ingresar el parámetro de tamaño del paciente y que esta variación es mayor a medida que los tamaños se van a los extremos.

Indices of agreement between neurosurgeons and a radiologist in interpreting tomography scans in an emergency department / Índice de concordância entre neurocirurgiões e radiologistas na interpretação de tomografias de crânio na emergência

The power of interpretation in the analysis of cranial computed tomography (CCT) among neurosurgeons and radiologists has rarely been studied. This study aimed to assess the rate of agreement in the interpretation of CCTs between neurosurgeons and a radiologist in an emergency department. Method 227 CCT were independently analyzed by two neurosurgeons (NS1 and NS2) and a radiologist (RAD). The level of agreement in interpreting the examination was studied. Results The Kappa values obtained between NS1 and NS2 and RAD were considered nearly perfect and substantial agreement. The highest levels of agreement when evaluating abnormalities were observed in the identification of tumors, hydrocephalus and intracranial hematomas. The worst levels of agreement were observed for leukoaraiosis and reduced brain volume. Conclusions For diseases in which the emergency room procedure must be determined, agreement in the interpretation of CCTs between the radiologist and neurosurgeons was satisfactory. .

O poder de interpretação na análise de tomografias de crânio (TCC) entre neurocirurgiões e radiologistas tem sido pouco estudada. O objetivo deste estudo é avaliar as taxas de concordância na interpretação de TCCs entre neurocirugiões e radiologista em um departamento de emergência. Método 227 TCCs foram independentemente analizadas por 2 neurocirugiões (NC1 e NC2) e um radiologista(RAD). O índice de concordância nas análises foi estudada posteriormente. Resultados O valor de Kappa obtido entre os NC1 e NC 2 e entre estes e RAD foram quase perfeitos e substancial respectivamente. O maiores índices de concordância quando avaliadas anormalidades foram observados na identificação de tumores, hidrocefalia e hematomas intracranianos. O piores índices foram observados com relação a leucaraiose e redução volumétrica. Conclusão Para doenças apresentadas em um departamento emergência que demandam tratamento mais agressivo o índice de concordância na interpretação de TCCs entre RAD e NC foi satisfatório. .

Estimativa dos valores de MSAD em procedimentos de tomografia computadorizada utilizando filmes radiocrômicos / Estimation of MSAD values in computed tomography scans using radiochromic films

OBJETIVO: Verificar a viabilidade de filmes radiocrômicos como um dosímetro alternativo para estimativa da dose média em cortes múltiplos a partir dos perfis de kerma.MATERIAIS E MÉTODOS: Os filmes foram distribuídos em cilindros posicionados no centro e nas regiões periféricas de um objeto simulador padrão de abdome utilizado para dosimetria em tomografia computadorizada.RESULTADOS: Os valores de dose média em cortes múltiplos calculados foram 13,6 ± 0,7, 13,5 ± 0,7 e 18,7 ± 1,0 mGy para os valores de passo (pitch) de 0,75, 1,00 e 1,50, respectivamente.CONCLUSÃO: Apesar de os resultados mostrarem valores menores que o nível de referência de radiodiagnóstico de 25 mGy estabelecido pela legislação brasileira para exames de abdome, eles sugerem que há espaço para otimização dos procedimentos e uma revisão do valor para o nível de referência de radiodiagnóstico brasileiro.

OBJECTIVE: To evaluate the feasibility of using radiochromic films as an alternative dosimeter to estimate the multiple scan average dose on the basis on kerma profiles.MATERIALS AND METHODS: The radiochromic films were distributed in cylinders positioned in the center and in four peripheral bores of a standard abdominal phantom utilized for computed tomography dosimetry.RESULTS: Values for multiple scan average dose values corresponded to 13.6 ± 0.7, 13.5 ± 0.7 and 18.7 ± 1.0 mGy for pitch of 0.75, 1.00 and 1.50, respectively.CONCLUSION: In spite of results showing lower values than the reference level for radiodiagnosis (25 mGy) established by the Brazilian regulations for abdominal studies, it is suggested that there is room to optimize procedures and review the reference level for radiodiagnosis in Brazil.

Primary Tumor Maximum Standardized Uptake Value Measured on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Is a Prognostic Value for Survival in Bile Duct and Gallbladder Cancer / 대한소화기학회지

BACKGROUND/AIMS: Few studies have assessed the prognostic value of the primary tumor maximum standardized uptake value (SUVmax) measured by 2-[18F]-fluoro-2-deoxy-D-glucose PET-CT for patients with bile duct and gallbladder cancer. METHODS: A retrospective analysis of 61 patients with confirmed bile duct and gallbladder cancer who underwent FDG PET-CT in Kangbuk Samsung Medical Center (Seoul, Korea) from April 2008 to April 2011. Prognostic significance of SUVmax and other clinicopathological variables was assessed. RESULTS: Twenty-three patients were diagnosed as common bile duct cancer, 17 as hilar bile duct cancer, 12 as intrahepatic bile duct cancer, and nine as gallbladder cancer. In univariate analysis, diagnosis of intrahepatic cholangiocarcinoma and gallbladder cancer, mass forming type, poorly differentiated cell type, nonsurgical treatment, advanced American Joint Committee on Cancer (AJCC) staging and primary tumor SUVmax were significant predictors of poor overall survival. In multivariate analysis adjusted for age and sex, primary tumor SUVmax (hazard ratio [HR], 4.526; 95% CI, 1.813-11.299), advanced AJCC staging (HR, 4.843; 95% CI, 1.760-13.328), and nonsurgical treatment (HR, 6.029; 95% CI, 1.989-18.271) were independently associated with poor overall survival. CONCLUSIONS: Primary tumor SUVmax measured by FDG PET-CT is an independent and significant prognostic factor for overall survival in bile duct and gallbladder cancer.

Software livre e de código aberto para avaliação de imagens de angiotomografia de coronárias / Free and open-source software application for the evaluation of coronary computed tomography angiography images

FUNDAMENTO: A estandardização do padrão de imagens utilizada dentro da medicina foi realizada em 1993 por meio do padrão DICOM (Digital Imaging and Communications in Medicine). Diversos exames utilizam esse padrão e cada vez mais são necessários softwares capazes de manipular esse tipo de imagem, porém esses softwares geralmente não têm o formato livre e de código aberto, e isso dificulta o seu ajuste para os mais diferentes interesses. OBJETIVO: Desenvolver e validar um software livre e de código aberto capaz de manipular imagens DICOM de exames de angiotomografia de coronárias. MÉTODOS: Desenvolvemos e testamos o software intitulado ImageLab na avaliação de 100 exames selecionados de forma randômica por meio de um banco de dados. Foram realizadas 600 análises divididas por dois observadores utilizando o ImageLab e um outro software comercializado junto a aparelhos de tomografia computadorizada Philips Brilliance, na avaliação da presença de lesões e placas coronarianas nos territórios do Tronco da Coronária Esquerda (TCE) e na Artéria Descendente Anterior (ADA). Para avaliar as concordâncias intraobservador, interobservadores e intersoftware, utilizamos concordância simples e estatística Kappa. RESULTADOS: As concordâncias observadas entre os softwares foram em geral classificadas como substancial ou quase perfeitas na maioria das comparações. CONCLUSÃO: O software ImageLab concordou com o software Philips na avaliação de exames de angiotomografia de coronárias especialmente em pacientes sem lesões, com lesões inferiores a 50% no TCE e inferiores a 70% na ADA. A concordância para lesão >70% na ADA foi menor, porém isso também é observado quando se utiliza o padrão de referência anatômico.

BACKGROUND: The standardization of images used in Medicine in 1993 was performed using the DICOM (Digital Imaging and Communications in Medicine) standard. Several tests use this standard and it is increasingly necessary to design software applications capable of handling this type of image; however, these software applications are not usually free and open-source, and this fact hinders their adjustment to most diverse interests. OBJECTIVE: To develop and validate a free and open-source software application capable of handling DICOM coronary computed tomography angiography images. METHODS: We developed and tested the ImageLab software in the evaluation of 100 tests randomly selected from a database. We carried out 600 tests divided between two observers using ImageLab and another software sold with Philips Brilliance computed tomography appliances in the evaluation of coronary lesions and plaques around the left main coronary artery (LMCA) and the anterior descending artery (ADA). To evaluate intraobserver, interobserver and intersoftware agreements, we used simple and kappa statistics agreements. RESULTS: The agreements observed between software applications were generally classified as substantial or almost perfect in most comparisons. CONCLUSION: The ImageLab software agreed with the Philips software in the evaluation of coronary computed tomography angiography tests, especially in patients without lesions, with lesions < 50% in the LMCA and < 70% in the ADA. The agreement for lesions > 70% in the ADA was lower, but this is also observed when the anatomical reference standard is used.

A computed tomography scoring system to assess pulmonary disease among premature infants / Um sistema de escore por tomografia computadorizada para avaliação da doença pulmonar em lactentes prematuros

CONTEXT AND OBJECTIVE: High-resolution computed tomography (HRCT) is considered to be the best method for detailed pulmonary evaluation. The aim here was to describe a scoring system based on abnormalities identified on HRCT among premature infants, and measure the predictive validity of the score in relation to respiratory morbidity during the first year of life. DESIGN AND SETTING: Prospective cohort study in Instituto Fernandes Figueira, Fundação Oswaldo Cruz. METHODS: Scoring system based on HRCT abnormalities among premature newborns. The affected lung area was quantified according to the number of compromised lobes, in addition to bilateral pulmonary involvement. Two radiologists applied the score to 86 HRCT scans. Intraobserver and interobserver agreement were analyzed. The score properties were calculated in relation to predictions of respiratory morbidity during the first year of life. RESULTS: Most of the patients (85 percent) presented abnormalities on HRCT, and among these, 56.2 percent presented respiratory morbidity during the first year of life. Scores ranged from zero to 12. There was good agreement between observers (intraclass correlation coefficient, ICC = 0.86, confidence interval, CI: 0.64-0.83). The predictive scores were as follows: positive predictive value 81.8 percent, negative predictive value 56.3 percent, sensitivity 39.1 percent, and specificity 90.0 percent. CONCLUSION: The scoring system is reproducible, easy to apply and allows HRCT comparisons among premature infants, by identifying patients with greater likelihood of respiratory morbidity during the first year of life. Its use will enable HRCT comparisons among premature infants with different risk factors for respiratory morbidity.

CONTEXTO E OBJETIVO: Tomografia computadorizada de alta resolução (TCAR) é considerada o melhor método para avaliação pulmonar detalhada. O objetivo foi descrever um sistema de escore baseado em alterações identificadas nas TCAR de lactentes prematuros e medir a validade preditiva do escore em relação à morbidade respiratória no primeiro ano de vida. TIPO DE ESTUDO E LOCAL: Estudo de coorte prospectiva no Instituto Fernandes Figueira, Fundação Oswaldo Cruz. MÉTODOS: Sistema de escore baseado em alterações nas TCAR de lactentes prematuros. A área pulmonar alterada foi quantificada conforme o número de lobos alterados, acrescido do comprometimento pulmonar bilateral. Dois radiologistas aplicaram o escore em 86 TCAR. Foram analisadas as confiabilidades intraobservador e interobservador e calculadas as propriedades do escore em relação à predição da morbidade respiratória no primeiro ano de vida. RESULTADOS: A maioria (85 por cento) dos pacientes apresentou TCAR anormal, e dentre estes, 56,2 por cento apresentaram morbidade respiratória no primeiro ano de vida. Valores do escore variaram de zero a 12. Houve boa concordância entre os observadores (coeficiente de correlação intraclasse, CCI = 0,86, intervalo de confiança, IC: 0,64-0,83). Os valores preditivos do escore foram: valor preditivo positivo 81,8 por cento, valor preditivo negativo 56,3 por cento, sensibilidade 39,1 por cento e especificidade 90,0 por cento. CONCLUSÃO: O sistema de escore é reprodutível, de fácil aplicação e permite a comparação de TCAR de pacientes prematuros, identificando pacientes com maior probabilidade de morbidade respiratória no primeiro de vida. Seu uso permitirá a comparação de TC de lactentes prematuros com diferentes fatores de risco para morbidade respiratória.

Tecnologias para investigação da DAC: relação entre publicações científicas e utilização clínica / Technologies for the investigation of CAD: association between scientific publications and clinical use

FUNDAMENTO: Apesar de algumas evidências sugerirem associação entre a exposição de uma tecnologia na literatura científica e sua difusão na prática clínica, poucos estudos avaliaram essa associação. OBJETIVO: O objetivo deste estudo é analisar se o padrão de publicação científica sobre duas tecnologias competitivas utilizadas na avaliação da doença arterial coronária (DAC) reflete o que ocorre na prática clínica. MÉTODOS: Avaliou-se o número de artigos científicos publicados anualmente na literatura médica (interesse científico global na tecnologia) sobre duas tecnologias utilizadas na avaliação da doença arterial coronária: tomografia computadorizada por feixe de elétrons e tomografia computadorizada com múltiplos detectores. Foi também analisado o número de países que publicam anualmente artigos científicos sobre essas tecnologias (interesse geográfico na tecnologia). RESULTADOS: A tomografia computadorizada por feixe de elétrons (electron beam computed tomography - EBCT) apresentou ápice de "interesse científico global" em 2001, com 127 artigos publicados. Após esse ápice, o "interesse científico global" diminuiu cerca de 50 por cento em 2008. Em oposição, o "interesse científico global" pela tomografia computadorizada com múltiplos detectores (multidetector computed tomography - MDCT) aumentou progressivamente até 2007, com 454 artigos publicados nesse ano. O "interesse científico geográfico" pela EBCT teve ápice em 2002, com 14 países publicando sobre essa tecnologia. Após esse ápice, "o interesse científico geográfico" declinou em quase 25 por cento até 2008, com 11 países publicando artigos sobre essa tecnologia. Em oposição, o "interesse científico geográfico" pela MDCT aumentou progressivamente até 2008, com 37 países publicando artigos sobre ela. CONCLUSÃO: A literatura científica médica é compatível com a substituição da EBCT pela MDCT na avaliação da DAC.

BACKGROUND: Although some evidence suggests an association between a technology exposure in the literature and its dissemination in clinical practice, few studies have evaluated such association. OBJECTIVE: To analyze whether the pattern of scientific publication on two competitive technologies used in the assessment of coronary artery disease (CAD) reflects what occurs in clinical practice. METHODS: The number of scientific articles published annually in the medical literature (global scientific interest in technology) on two technologies used in the assessment of CAD was evaluated: electron beam computed tomography (EBCT) and multidetector computed tomography (MDCT). The number of countries that annually publish scientific articles about these technologies (geographic interest in the technology) was also analyzed. RESULTS: The EBCT showed a peak of "global scientific interest" in 2001, with 127 published articles. After this peak, the "global scientific interest" decreased by around 50 percent in 2008. In opposition, the "global scientific interest" for MDCT progressively increased up to 2007, with 454 articles published in that year. The "geographic scientific interest" by EBCT showed a peak in 2002, with 14 countries publishing about this technology. After this peak, the "geographic scientific interest" decreased by almost 25 percent up to 2008, with 11 countries publishing about this technology. In opposition, the "geographic scientific interest" by MDCT progressively increased up to 2008, with 37 countries publishing articles about it. CONCLUSION: The medical scientific literature is compatible with the substitution of EBCT by MDCT in the assessment of CAD.

Image Quality Improvement after Implementation of a CT Accreditation Program

OBJECTIVE: The purpose of this study was to evaluate any improvement in the quality of abdominal CTs after the utilization of the nationally based accreditation program. MATERIALS AND METHODS: Approval was obtained from the Institutional Review Board, and informed consent was waived. We retrospectively analyzed 1,011 outside abdominal CTs, from 2003 to 2007. We evaluated images using a fill-up sheet form of the national accreditation program, and subjectively by grading for the overall CT image quality. CT scans were divided into two categories according to time periods; before and after the implementation of the accreditation program. We compared CT scans between two periods according to parameters pertaining to the evaluation of images. We determined whether there was a correlation between the results of a subjective assessment of the image quality and the evaluation scores of the clinical image. RESULTS: The following parameters were significantly different after the implementation of the accreditation program: identifying data, display parameters, scan length, spatial and contrast resolution, window width and level, optimal contrast enhancement, slice thickness, and total score. The remaining parameters were not significantly different between scans obtained from the two different periods: scan parameters, film quality, and artifacts. CONCLUSION: After performing the CT accreditation program, the quality of the outside abdominal CTs show marked improvement, especially for the parameters related to the scanning protocol.

Tomographic assessment of the spine in children with spondylocostal dysotosis syndrome

OBJECTIVE: The aim of this study was to perform a detailed tomographic analysis of the skull base, craniocervical junction, and the entire spine in seven patients with spondylocostal dysostosis syndrome. METHOD: Detailed scanning images have been organized in accordance with the most prominent clinical pathology. The reasons behind plagiocephaly, torticollis, short immobile neck, scoliosis and rigid back have been detected. Radiographic documentation was insufficient modality. RESULTS: Detailed computed tomography scans provided excellent delineation of the osseous abnormality pattern in our patients. CONCLUSION: This article throws light on the most serious osseous manifestations of spondylocostal dysostosissyndrome.

Predictive success factors for ct-guided fine needle aspiration biopsy of pulmonary lesions

OBJECTIVE: Computed tomography-guided percutaneous fine needle aspiration biopsy of lung lesions is a simple, safe and reproducible procedure. Currently, it is widely used to diagnose lung lesions. However, different factors can influence the success rates of this procedure. The purpose of this study was to determine the influence of radiological and procedural characteristics in predicting the success rates of computed tomography-guided fine needle aspiration biopsy of lung lesions. SUBJECTS AND METHODS: A retrospective study was developed and involved 340 patients who were submitted to a consecutive series of 362 computed tomography-guided fine needle aspiration biopsies of lung lesions, between July 1996 and June 2004, using 22-gauge needles (Chiba). Variables such as the radiological characteristics of the lesions, secondary pulmonary radiological findings, and procedural techniques were studied. RESULTS: For this study, 304 (84 percent) fine needle aspiration biopsies of lung lesions provided sufficient material for cytological evaluation. The variables that predicted sufficient material for cytological evaluation were lesions larger than 40 mm (p=0.02), lesions on the superior lung lobes (p=0.02), and suspicion of primary lung malignancy (p=0.03). From the multivariate analysis, the only predictive variable for success of the biopsies was localization on the superior lobes (p=0.01). CONCLUSIONS: Computed tomography-guided percutaneous fine needle aspiration biopsy of lung lesions showed greater rates of success in biopsies performed in patients with suspicion of primary lung malignancy, with lesions located in the superior lobes, and that have diameters equal to and larger than 40 mm.

Avaliação da rinussinusite bacteriana aguda em pacientes asmáticos com base em parâmetros clínicos, exame otorrinolaringológico e estudo de imagem / Evaluation of acute bacterial rhinosinusitis in asthma patients based on clinical parameters and imaging studies, together with ear, nose and throat examination

OBJETIVO: Avaliar os seios paranasais em pacientes com asma estável ou asma aguda para determinar a prevalência de rinossinusite bacteriana aguda. MÉTODOS: Estudo transversal incluindo 30 pacientes com asma aguda (73 por cento do sexo feminino) tratados na sala de emergência e 30 pacientes com asma estável (80 por cento do sexo feminino) regularmente acompanhados em ambulatório. Todos os pacientes responderam a um questionário sobre sinais e sintomas respiratórios e foram submetidos a exame otorrinolaringológico e a radiograma e tomografia computadorizada de seios paranasais. RESULTADOS: Com base no diagnóstico clínico, a prevalência de rinossinusite bacteriana aguda foi de 40 por cento nos pacientes com asma aguda e de 3 por cento nos com asma estável. O exame otorrinolaringológico e os exames de imagem isoladamente não foram úteis para a confirmação diagnóstica. CONCLUSÕES: O exame otorrinolaringológico e o radiograma e a tomografia de seios paranasais por si só não foram úteis para o diagnóstico de rinossinusite bacteriana aguda. Nossos resultados confirmam a evidência de que o diagnóstico clínico de rinossinusite aguda deve ser dado com cautela.

OBJECTIVE: To evaluate paranasal sinuses in patients with stable or acute asthma in order to determine the prevalence of acute bacterial rhinosinusitis. METHODS: A cross-sectional study including 30 patients with acute asthma (73 percent females) treated in the emergency room and 30 patients with stable asthma (80 percent females) regularly monitored as outpatients. All patients completed a questionnaire on respiratory signs and symptoms and were submitted to ear, nose and throat (ENT) examination, as well as to X-ray and computed tomography (CT) imaging of the sinuses. RESULTS: Based on the clinical diagnosis, the prevalence of acute bacterial rhinosinusitis was 40 percent in the patients with acute asthma and 3 percent in those with stable asthma. The ENT examination findings and the imaging findings in isolation were not useful to confirm the diagnosis. CONCLUSIONS: In themselves, ENT examination findings, X-ray findings and CT findings were not useful for the diagnosis of acute bacterial rhinosinusitis. Our results provide further evidence that a clinical diagnosis of bacterial rhinosinusitis should be made with caution.

Diagnóstico auxiliado por computador na detecção de nódulos pulmonares pela tomografia computadorizada com múltiplos detectores: estudo preliminar de 24 casos / Detection of pulmonary nodules by computer-aided diagnosis in multidetector computed tomography: preliminary study of 24 cases

OBJETIVOS: Avaliar o desempenho de um programa para auxílio na detecção de nódulos pulmonares em tomografia computadorizada com múltiplos detectores (TCMD). MÉTODOS: Foram avaliadas 24 tomografias computadorizadas de tórax consecutivas realizadas no Centro de Medicina Diagnóstica Fleury no período de 07/10/2006 a 19/10/2006 usando um tomógrafo helicoidal multidetectores de 64 canais. O estudo compreendeu 12 pacientes do sexo feminino e 12 do sexo masculino, com idades variando entre 35 e 77 anos, idade média de 57,9. As imagens foram analisadas independentemente pelo método da dupla leitura e pelo programa diagnóstico auxiliado por computador (DAC). Os nódulos encontrados nos diferentes processos foram registrados e os dados comparados. RESULTADOS: A sensibilidade total da detecção de nódulos pelo DAC nesse trabalho foi de 16,5 por cento, 55 por cento excluindo os nódulos medindo <4 mm. A sensibilidade separada por tamanho foi de 6,5 por cento para nódulos <4 mm, 45 por cento para nódulos de 4 a 6 mm, 100 por cento para nódulos de 6 mm a 1 cm, e 0 por cento para nódulos >1 cm. Menos de 1 por cento dos nódulos verdadeiros destacados pelo DAC não haviam sido registrados no processo de dupla leitura. CONCLUSÕES: Neste trabalho preliminar de 24 casos, o programa testado não conseguiu superar de forma significativa a sensibilidade da dupla leitura realizada de rotina neste serviço.

OBJECTIVES: To evaluate the performance of a computer program designed to facilitate the detection of pulmonary nodules using multidetector computed tomography (MDCT) scans of the chest. METHODS: We evaluated 24 consecutive MDCT scans of the chest at the Fleury Diagnostic Imaging Center during the period from October 7 to October 19 of 2006, using a 64-channel CT scanner. The study comprised 12 females and 12 males, ranging from 35 to 77 years of age (mean, 57.9 years). Double reading and a computer-aided diagnosis (CAD) system were used in order to perform two independent analyses of the data. The nodules found using both methods were recorded, and the data were compared. RESULTS: The total sensitivity of CAD for the detection of nodules was 16.5 percent, increasing to 55 percent when nodules <4 mm in diameter were excluded. Sensitivity by diameter was 6.5 percent for nodules <4 mm, 45 percent for nodules of 4-6 mm, 100 percent for nodules of 6 mm-10 cm, and 0 percent for nodules >1 cm. More than 99 percent of true nodules detected by CAD were registered in the image double reading process. CONCLUSIONS: In this preliminary 24-case study, the sensitivity of computer program tested was not significantly greater than that of the double-reading process that is routinely performed in this facility.

Review of Failed CT Phantom Image Evaluations in 2005 and 2006 by the CT Accreditation Program of the Korean Institute for Accreditation of Medical Image

OBJECTIVE: The CT accreditation program was established in 2004 by the Korean Institute for Accreditation of Medical Image (KIAMI) to confirm that there was proper quality assurance of computed tomography (CT) images. We reviewed all the failed CT phantom image evaluations performed in 2005 and 2006. MATERIALS AND METHODS: We analyzed 604 failed CT phantom image evaluations according to the type of evaluation, the size of the medical institution, the parameters of the phantom image testing and the manufacturing date of the CT scanners. RESULTS: The failure rates were 10.5% and 21.6% in 2005 and 2006, respectively. Spatial resolution was the most frequently failed parameter for the CT phantom image evaluations in both years (50.5% and 49%, respectively). The proportion of cases with artifacts increased in 2006 (from 4.5% to 37.8%). The failed cases in terms of image uniformity and the CT number of water decreased in 2006. The failure rate in general hospitals was lower than at other sites. In 2006, the proportion of CT scanners manufactured before 1995 decreased (from 12.9% to 9.3%). CONCLUSION: The continued progress in the CT accreditation program may achieve improved image quality and thereby improve the national health of Korea.

CT Angiography for Living Kidney Donors: Accuracy, Cause of Misinterpretation and Prevalence of Variation

OBJECTIVE: To determine the accuracy of the use of multi-detector row CT (MDCT) to predict vascular anatomy in living kidney donors and to reveal the prevalence of vascular variations in a Korean population. MATERIALS AND METHODS: A total of 153 living kidney donors that had undergone preoperative CT and nephrectomy, either with open or laparoscopic surgery, were selected retrospectively. The initial CT results were compared with the surgical findings and repeated review sessions of CT scans were performed to determine the causes of mismatches in discordant cases. RESULTS: The accuracy of CT angiography was 95% to predict the number of renal vessels. Four arteries and two veins were missed during the initial CT interpretation due to perception errors (for two arteries and two veins) and technical limitations (two arteries). The prevalence of multiple renal arteries and veins, early branching of a renal artery and late confluence of a renal vein were 31%, 5%, 12%, 17%, respectively. The circumaortic renal vein and the bilateral inferior vena cava were found in two cases each (1.3%). One case (0.7%) each of a retroaortic renal vein and a supradiaphragmatic originated renal artery were found. CONCLUSION: MDCT provides a reliable method to evaluate the vascular anatomy and variations of living kidney donors.