OBJECTIVE: The objective of the present study is to analyze the optimization of fluoroscopic image quality and patient entrance surface air kerma rate in interventional radiology procedures, utilizing a phantom adapted for fluoroscopy. MATERIALS AND METHODS: The authors utilized a phantom developed for evaluating conventional radiological images adapted for fluoroscopy through the addition of two catheters with different diameters, both of them utilized in interventional radiology. The patient entrance surface air kerma rate was determined with the aid of this phantom. RESULTS: The evaluation of technical parameters for different exposure modes of a digital fluoroscopic imaging system has allowed the determination of the air kerma rate, enabling the optimization of the image quality in interventional procedures. The decrease in the patient entrance surface air kerma rate may achieve 67%. CONCLUSION: The optimization of fluoroscopic image quality achieved with a phantom allows reducing the patient entrance surface air kerma with no significant loss of diagnostic performance.

Keywords: Images optimization, Fluoroscopy, Phantom, Dose reduction

OBJECTIVE: To evaluate the development of children with vertically transmitted HIV infection by comparing two methods for bone age assessment. MATERIALS AND METHODS: A total of 100 children aged between 4 years and two months and 11 years and 9 months were studied. The hands and wrists of the children were X-rayed using standard techniques and the films were subsequently analyzed according to the Greulich & Pyle (1959) and by Eklöf & Ringertz (1967) methods. RESULTS: The results showed statistically significant differences between the two methods, with the Eklöf & Ringertz method being distinguished by higher sensitivity (p < 0.05). In the group of female patients statistically significant differences were seen between control and HIV+ cases (seven cases) when assessed using this method (p < 0.05). CONCLUSION: The study showed that HIV influenced skeletal development in this group of patients.

Keywords: Skeletal age, HIV infection, Children, Eklöf & Ringertz, Greulich & Pyle

OBJECTIVE: To implement a protocol for correction of images acquired by videofluoroscopy based on the mathematical model described by Baltzopoulos (1995) and to evaluate the magnitude of error in the linear and non-linear calibration methods. MATERIALS AND METHODS: The images were acquired using a Axion Siemens Iconos R100 videofluoroscope from one individual during knee extension exercise. A non-linear calibration pattern was used for the correction of the images. Data was processed using a Silicon Graphics 320 capture plate and subsequently analyzed using the Matlab software. RESULTS: In order to demonstrate the method's applicability, the deformation of the patellar ligament was evaluated. The use of a linear calibration pattern produced a maximum error of 0.086 mm, while the non-linear calibration pattern reached a maximum value of 0.019 mm. According to the mean error, the linear calibration was 0.024 mm, and the non-linear presented a value of 0.007 mm. CONCLUSION: The results show the need to use a non-linear calibration procedure.

Keywords: Videofluoroscopy, Images calibration, Patellar ligament, Knee

We present the preliminary results of testing and acceptance of a method for displaying medical images that employs simple computer freewares that can be run in unsophisticated computational platforms, which are commonly underutilized. This method allows easy and accessible visualization, printing, documenting, archiving, consulting and electronic transmission of a wide range of medical images without the need of expensive, complex and difficult to learn softwares.

Keywords: Medical images, Freeware, Ultrasound

OBJECTIVE: To present the process of implementation of toolkits for visualization of medical images using DICOM and to review the basis and characteristics of this protocol. In this paper we present a VDTApplication for visualization of local and remote images, and a VDTApplet that allows the visualization of images on a web browser. MATERIALS AND METHODS: The toolkits were implemented using Java programming language. For the development of this toolkit we considered the different version of the DICOM protocol, creating a generic system capable of reading and opening images generated by different modalities of different manufacturers. The tools were evaluated qualitatively by doctors taking into account the system's interface, image quality and image adjustment. RESULTS: The evaluation score ranged from 1 (very poor ) to 5 (very good) for each item, with the following results: 5 for system interface, 4 for image quality and 3 for the image adjustment. Based on the scores obtained we concluded that the tools can be considered good. CONCLUSION: These results allowed us to conclude that these tools are practical, user friendly and should be added to the PACS (picture archiving and communication system) of "Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo", Ribeirão Preto, SP, Brazil.

Keywords: Medical images, DICOM, Filmless radiology, Medical images visualization

The authors report a case of osteopoikilosis in a woman with HIV infection and pulmonary tuberculosis, and bone abnormalities suggestive of osteopoikilosis. The diagnosis of osteopoikilosis was incidental. Plain films and computed tomography images as well as a review of the literature are presented. To our knowledge this is the first report of association of these diseases.

Keywords: Osteopoikilosis, HIV, Radiology

Objective: To investigate the correlation between frontal regions cortical thickness measured by magnetic resonance imaging of HIV-positive patients and their performance on instruments for assessing executive functions. Materials and Methods: The present study included 22 HIV-positive patients in the age range from 45 to 65, schooling ranging between three and 20 years, with executive functions deficit and undergoing antiretroviral therapy. Magnetic resonance imaging was performed with conventional T1-weighted, 3D sequences and the images were processed with the Freesurfer software to measure cortical thickness. The following instruments were utilized to evaluate the patients' executive functions: Trail Making, Wisconsin, Hayling, working memory (WAIS-III), verbal fluency and Stroop tests. The Pearson's correlation coefficient was utilized in the data statistical analysis. Results: Significant correlations were found between: Wisconsin scores and the thickness of the right pre-central, lateral and left pre-central orbitofrontal regions; Trail Making scores and thickness of right pre-central and left anterior caudal cingulate areas; and Hayling Test scores and thickness of the left lateral orbitofrontal area. Conclusion: Correlations between cortical thickness measurements by magnetic resonance imaging and cognitive performance suggest that the executive function deficit in HIV-positive patients are related to a reduction in the thickness of the frontal cortex.

Keywords: Magnetic resonance imaging; Cortical thickness; Frontal lobe; Neuropsychological; Executive functions; HIV.

Objective: The present study is aimed at describing computed tomography findings pulmonary tuberculosis in adult AIDS patients assisted at a radiology unit of a reference infectious diseases hospital, in an attempt to establish the association between such findings and CD4 count. Materials and Methods: Forty-five patients were evaluated by chest computed tomography over a four-year period. Results: Mediastinal and/or hilar lymph node enlargement was found in 31 (68.8%) cases, pleural effusion in 29 (64.4%), centrilobular nodules with segmental distribution in 26 (57.7%), consolidation in 24 (53.3%), confluent micronodules in 17 (37.7%), poorly defined nodules with centrilobular distribution in 16 (35.5%), tree-in-bud pattern in 13 (28.9%), bronchial wall thickening in 12 (26.6%), thick-walled cavity in 10 (22.2%), miliary nodules in 9 (20%), and cylindrical bronchiectasis in 6 (13.3%). Among the 45 patients, 35 (77.8%) presented CD4 count < 200 cel/mm³ and 10 (22.2%) presented CD4 count > 200 cel/mm³. Conclusion: Differently from reports in the literature, the authors conclude that mediastinal and/or hilar lymph node enlargement and consolidation were significantly most frequent in patients with CD4 count > 200 cel/mm³. However, lymph nodes with hypodense center were most often observed in severely immunosuppressed patients with CD4 count < 200 cel/mm³.

Keywords: Tuberculosis; Tomography; Chest; HIV; AIDS; SIDA.

Objetivo: A principal utilidade da tomografia por emissão de pósitrons com 18-fluordeoxiglicose (FDG-PET) está no estadiamento do câncer de pulmão. Porém, ela também pode ser utilizada para diferenciar lesões pulmonares indeterminadas, mas seu impacto na ressecção cirúrgica de lesões benignas é desconhecido. O objetivo deste estudo foi comparar a prevalência de lesões benignas em toracotomias feitas por suspeição de câncer de pulmão, antes e após a introdução do FDG-PET, em um centro de referência de cirurgia torácica. Materiais e Métodos: Os autores analisaram, prospectivamente, uma base de dados cirúrgicos de todos os pacientes consecutivos submetidos a toracotomia por câncer de pulmão suspeito ou comprovado e compararam a prevalência de lesões benignas em dois grupos ao longo de dois anos consecutivos, respectivamente antes (grupo I) e depois (grupo II) da introdução da FDG-PET. Resultados: Ressecção cirúrgica foi feita em 1.233 pacientes durante o período do estudo. A prevalência de lesões benignas na cirurgia nos grupos I e II foi similar (44/626 e 41/607, ambas correspondendo a 7%), e também no grupo II, entre aqueles submetidos a FDG-PET e os restantes (21/301 e 20/306 respectivamente, ambos correspondendo a 7%). No grupo II, dos 21 pacientes com lesões benignas submetidos a FDG-PET, 19 tiveram um estudo falso-positivo (valor médio padrão de captação 5.3 [faixa 2.6–12.7]). Desses, respectivamente 13 e 4 pacientes tiveram broncoscopia não diagnóstica e biópsia transtorácica percutânea de pulmão antes da toracotomia. Não houve diferença na proporção de lesões benignas diferentes ressecadas entre o grupo I e aqueles submetidos a FDG-PET no grupo II. Conclusão: A introdução da FDG-PET não alterou a proporção de pacientes submetidos a toracotomia por lesões benignas, principalmente devido à avidez pelo isótopo de algumas lesões não malignas. Tais resultados falsos-positivos devem ser considerados nos casos em que se contempla a possibilidade de ressecção cirúrgica em pacientes com câncer de pulmão não confirmado.

Keywords: Tomografia por emissão de pósitrons; Tomografia computadorizada; Pulmão – lesões benignas ou congênitas; Câncer de pulmão – diagnóstico e estadiamento; Câncer de pulmão – cirurgia.

Objetivo: Avaliar a percepção de médicos residentes em radiologia de 4º ano sobre as melhores modalidades de imagem na investigação de neoplasias e trauma. Materiais e Métodos: Vinte e sete médicos residentes de 4º ano de quatro programas de residência em radiologia americanos participaram do estudo. Aos participantes foi perguntado sobre a melhor modalidade de imagem para se avaliar o cérebro e a coluna vertebral, pulmões, abdome e o sistema musculoesquelético. As modalidades de imagem disponíveis foram: RM, TC, ultrassonografia, PET e radiografia simples. Todos os achados foram comparados com os Critérios de Adequação de Exames de Imagem e Radioterapia do ACR. Resultados: A RM foi escolhida como melhor modalidade de imagem para se avaliar neoplasias encefálicas, espinhais, abdominais e musculoesqueléticas por 96,3%, 100%, 70,4% e 63% dos residentes, respectivamente. A TC foi escolhida por 88,9% dos residentes para avaliar neoplasias pulmonares. A modalidade de imagem ótima para se avaliar trauma foi a TC para lesões encefálicas (100%), espinhais (92,6%), pulmonares (96,3%), abdominais (92,6%) e grandes lesões traumáticas musculoesqueléticas (74,1%); a RM foi escolhida para lesões esportivas (96,3%). Observou-se concordância com os critérios de adequação do ACR. Conclusão: Houve concordância entre a percepção dos residentes sobre as melhores modalidades de imagem para avaliação de neoplasias e trauma e os critérios de adequação do ACR.

Keywords: Formação de residentes; Educação médica; Modalidades de imagem.

The authors report a rare case of frontal sinus pneumocele in a 26-year-old female patient assessed by computed tomography.

Keywords: Pneumocele; Frontal sinus; Computed tomography.

Raspberry Pi is a low-cost computer created with educational purposes. It uses Linux and, most of times, freeware applications, particularly a software for viewing DICOM images. With an external monitor, the supported resolution (1920 × 1200 pixels) allows for the set up of simple viewing workstations at a reduced cost.

Keywords: Raspberry Pi; DICOM; Images; Viewing; Low cost.

OBJECTIVE: To assess the percent agreement between diagnostic imaging modalities for the evaluation of lymphadenopathies in HIV-infected/AIDS patients. MATERIALS AND METHODS: This was an open, comparative, prospective study of diagnostic imaging methods for lymphadenopathy evaluation. We evaluated 30 patients (19 men and 11 women). All underwent ultrasound and computed tomography (CT). Twenty of the patients also underwent magnetic resonance imaging (MRI). We determined the percent agreement between two examiners using the various imaging methods to evaluate lymphadenopathies. RESULTS: CT had the highest percent agreement, at 93.3%, with a kappa coefficient of 0.85, corresponding to 28 of the 30 examinations. When we compared the percent agreement between the two examiners and between CT and ultrasound, examiner 1 had an observed rate of 80.0%, with a kappa of 0.49, corresponding to 24 of the 30 examinations, whereas examiner 2 had a rate of 70.0%, with a kappa of 0.31, corresponding to 21 of the 30 examinations. Between MRI and CT, the percent agreement for examiner 1 was 50.0%, with a kappa of −0.18, corresponding to 10 of the 20 examinations, whereas that for examiner 2 was 85.0%, with a kappa of 0.69, corresponding to 17 of the 20 examinations. For MRI and ultrasound, examiner 1 had a percent agreement of 70.0%, with a kappa of 0.20, corresponding to 14 of the 20 examinations, and examiner 2 had a percent agreement of 75.0%, with a kappa of 0.38, corresponding to 15 of the 20 examinations. CONCLUSION: This study indicates that intermethod agreement is highly dependent on the way in which the research is conducted, rather than on the level of experience of the examiner.

Keywords: HIV; Acquired immunodeficiency syndrome; Lymphadenopathy; Ultrasonography; Tomography, X-ray computed; Magnetic resonance imaging..

OBJECTIVE: We aimed to evaluate whether human immunodeficiency virus (HIV)-positive patients with and without clinically significant memory deficits and healthy control participants differ on in vivo hydrogen-1 magnetic resonance spectroscopy (H-MRS) in the posterior cingulate gyri. MATERIALS AND METHODS: In total, 21 HIV-positive patients with memory deficit (HIV+wMD) were compared with 15 HIV-positive patients without memory deficit (HIV+wOMD) and 22 sex-, age-, and education-matched control participants. Memory impairments were classified based on the participants’ performance on the Rey Auditory Verbal Learning Test. Short echo time (30 ms), single-voxel H-MRS was performed using a 1.5-T magnetic resonance scanner. RESULTS: The HIV+wMD and HIV+wOMD groups had higher choline/creatine ratio in the posterior cingulate gyri than the control group. There were no significant metabolite ratio differences between the HIV+wMD and HIV+wOMD groups. CONCLUSION: HIV-positive patients with and without memory deficits had significantly higher choline/creatine ratios than controls in the posterior cingulate gyri, which may reflect cerebral inflammation, altered cell membrane metabolism, microgliosis, and/or astrocytosis.

Keywords: HIV; Memory deficit; Posterior cingulate gyrus; Magnetic resonance spectroscopy.

Os nervos cranianos representam extensões das estruturas funcionais do cérebro que cruzam a cabeça e o pescoço. Eles estão ligados a diferentes estruturas cranianas e se relacionam com diversas doenças. Uma compreensão profunda de sua complexa anatomia e aparência normal de imagem permite ao examinador identificar e caracterizar com mais precisão as anormalidades. A ressonância magnética com contraste é uma importante ferramenta para avaliar essas estruturas, especialmente as sequências tridimensionais de precessão livre de estado estacionário, que proporcionam alta resolução espacial e de partes moles, apesar da fina espessura dos nervos cranianos. Na maioria dos casos, os achados de imagem são inespecíficos, e uma anamnese completa, exame físico dirigido e testes laboratoriais são necessários para estreitar o diagnóstico diferencial. Este ensaio iconográfico ilustra e discute doenças congênitas, traumáticas e vasculares dos nervos cranianos, mostrando imagens em uma abordagem fisiopatológica.

Keywords: Neuroimagem/métodos; Radiologia/métodos; Ressonância magnética/métodos; Nervos cranianos/diagnóstico por imagem.