The authors present a list of recommendations on the utilization of 18F-FDG PET/CT in oncology for the diagnosis, staging and detection of cancer, as well as in the follow-up of the disease progression and possible recurrence. The recommendations were based on the analysis of controlled studies and a systematic review of the literature including both retrospective and prospective studies regarding the clinical usefulness and the impact of 18F-FDG PET/CT on the management of cancer patients. 18F-FDG PET/CT should be utilized as a supplement to other conventional imaging methods such as computed tomography and magnetic resonance imaging. Positive results suggesting changes in the clinical management should be confirmed by histopathological studies. 18F-FDG PET should be utilized in the diagnosis and appropriate clinical management of cancer involving the respiratory system, head and neck, digestive system, breast, genital organs, thyroid, central nervous system, besides melanomas, lymphomas and occult primary tumors.

Keywords: FDG-PET; Oncology; Diagnosis; Clinical indications.

Objective: The present study was aimed at evaluating the reliability of the qualitative visual assessment of brain abnormalities using conventional brain MRI in extremely preterm infants. Materials and methods: A cohort of 45 consecutive infants with gestational age of 30 weeks or less (median of 27 weeks, ranging from 25 to 30 weeks) was enrolled in this study. Two independent, experienced neuroradiologists blindly reviewed MRI studies of the infants’ brain for diffuse and excessive high-signal intensity (DEHSI), dilated lateral ventricles, intracranial hemorrhage, areas of abnormal signal in the basal ganglia and cortex, cyst-like areas, ventricular deformities, enlargement of subarachnoid spaces, early leukoencephalomalacia, and cortical abnormalities. Results: Forty-one patients (91.1%) presented abnormalities at MRI. The most common findings were DEHSI in the white matter (75.6%) and ventricular dilatation (42.2%). The interobserver agreement was high (κ > 0.60) for most of the abnormal MRI findings. The kappa statistic values were moderate for enlargement of the subarachnoid space (κ = 0.52) and was only low for DEHSI in the white matter (κ = 0.39). Conclusion: Conventional MRI seems to be a reliable method for evaluating the most common brain abnormalities in extremely premature infants; however, the presence of DEHSI in the white matter demonstrated to be is a less reliable finding.

Keywords: Preterm; Brain; Magnetic resonance imaging; Imaging; Hypoxia.

Objective: To describe the MR imaging features of hepatic hemangioma with perilesional enhancement. Materials and methods: A search was performed of the MRI section database to identify all cases of hepatic hemangioma with perilesional enhancement between March 2008 and July 2009. All patients underwent MR examinations including precontrast T1- and T2-weighted images and postgadolinium dynamic images. On MR images, characteristics of the hemangioma and perilesional enhancement were evaluated. Results: Seven hemangiomas in seven patients (five men, two women; age range, 41–69 years; mean, 57 years) were included in this study. Lesion size ranged from 7 to 20 mm (mean, 12.4 mm). On hepatic arterial dominant phase, all seven hemangiomas exhibited wedge-shaped perilesional enhancement which faded on two minutes postgadolinium images. Four of these lesions demonstrated adjacent capsular enhancement. Conclusion: All hepatic hemangiomas with perilesional enhancement were < 2 cm capsulebased lesions. This location suggests that these hemangiomas may conscript capsular vessels to account for the perilesional enhancement.

Keywords: Liver; Liver hemangioma; Liver perfusion; Liver contrast enhancement.

Objective: To evaluate endothelial function in patients with risk factors for atherosclerosis by measuring brachial artery flow-mediated dilatation (BAFMD) and intima-media thickness (IMT) of carotid and brachial arteries. Materials and methods: A cross-sectional, case-control study in which endothelial function was evaluated by measurement of BAFMD and IMT of carotid and brachial arteries and presence or absence of risk factors in 112 patients distributed as follows: women with risk factors (n = 49), women control group (n = 24), men with risk factors (n = 21), men control group (n = 18). Results: BAFMD was significantly compromised in the group with risk factors as compared with the control group, regardless of sex: in women, 15.2 Χ 25.3 (p < 0.01); in men, 11.8 Χ 16.8 (p < 0.02). On the other hand, IMT was not significant both for the carotid and brachial arteries, regardless of sex: brachial artery in women, 0.3 Χ 0.3 (p < 0.06); brachial artery in men, 0.36 Χ 0.23 (p < 0.07); carotid artery in women, 0.6 Χ 0.4 (p < 0.07); carotid artery in men, 0.85 Χ 0.38 (p < 0.08). The significance level was set at 5% (p < 0.05). Conclusion: Measurement of BAFMD was effective for detecting endothelial impairment in a population with risk factors for atherosclerosis.

Keywords: Atherosclerosis; Endothelial dysfunction; Brachial artery flow-mediated dilatation; Intima-media complex of the carotid and brachial arteries.

Dengue virus infection is endemic in tropical and subtropical areas. Symptomatic dengue infection is classified into dengue fever or dengue hemorrhagic fever with a tendency to develop shock syndrome. Dengue hemorrhagic fever is characterized by hemorrhagic manifestations, thrombocytopenia and increased capillary permeability. Dengue shock syndrome presents findings of dengue hemorrhagic fever with hypotension. Many sonographic findings have been described, including pleural effusion, ascites, gallbladder wall thickening and pericardial effusion. The aim of the present review is to describe sonographic findings and to demonstrate the role of ultrasonography in the assessment of children with suspected dengue hemorrhagic fever.

Keywords: Dengue; Dengue hemorrhagic fever; Dengue shock syndrome; Pleural effusion; Ultrasonography.

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: To evaluate the role of ultrasonography in the assessment of histopathological changes in patients with chronic hepatitis C, with emphasis on hepatic steatosis. Materials and Methods: Liver ultrasonography results were compared with histopathological findings of liver biopsy of 192 patients with chronic hepatitis C virus infection. All the US examinations followed a single protocol, analyzing the following aspects: echogenicity, echotexture and attenuation. The patients sample was divided into two groups as follows: patients with sonographic changes and patients with no sonographic changes. Sonographic findings of both groups were compared with histopathological findings after liver biopsy. Results: Statistically significant intergroup differences were observed just regarding architectural changes grades 0 and 3 and hepatic steatosis. Attenuation was the sonographic criterion that was best correlated with hepatic steatosis. Conclusion: The results of the present study demonstrate that, in patients with chronic hepatitis C, ultrasonography has limitations in the characterization of histopathological changes, with an intermediate rate of agreement with the diagnosis of hepatic steatosis. Considering the specificity of 77.9% and the negative predictive value of 95.5%, the authors highlight the capacity of the method to demonstrate the probability of absence of hepatic steatosis.

Keywords: Ultrasonography; Chronic hepatitis C virus infection; Hepatic steatosis; Liver biopsy.

Objective: To validate the proposal for development of a virtual collaborative environment for training of nuclear medicine personnel. Materials and Methods: Organizational assumptions, constraints and functionalities that should be offered to the professionals in this field were raised early in the development of the environment. The prototype was developed in the Moodle environment, including data storage and interaction functionalities. A pilot interaction study was developed with a sample of specialists in nuclear medicine. Users’ opinions collected by means of semi-structured questionnaire were submitted to quantitative and content analysis. Results: The proposal of a collaborative environment was validated by a community of nuclear medicine professionals and considered as an aid in the training in this field. Suggestions for improvements and new functionalities were made. There is a need to establish a program for education of moderators specifically for this environment, considering the different interaction characteristics as the online and conventional teaching methods are compared. Conclusion: The collaborative environment will allow the exchange of experiences and case discussions among professionals from institutions located in different regions all over the country, enhancing the collaboration among them. Thus, the environment can contribute in the early and continued education of nuclear medicine professionals.

Keywords: Collaborative environment; Nuclear medicine; Medical education; Distance education.

Objective: To propose a reproducible, user friendly and low cost method for digitization of radiographic films of all the standard sizes, focusing efforts on chest X-ray films. Materials and Methods: The focus on low cost have dictated the use of an A4 scanner with transparency adapter, as well as an optimized image stitching software that takes advantage of the scanner geometry and constant capture area, besides the knowledge of the standard X-ray film sizes. Results: The end result of the proposed method is a high resolution image with good contrast and no perceptible stitching artifacts. Conclusion: The proposed digitization method with an A4 scanner allows reproducibility, excellent image quality and high degree of certainty in the identification of lesions.

Keywords: Digital radiology; Teleradiology; Image stitching.

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.

OBJECTIVE: To assess the degree of acceptance of patients undergoing computed tomography colonography (CTC) in comparison with colonoscopy in the screening of colorectal disease. MATERIALS AND METHODS: Fifty patients with suspected colorectal disease underwent CTC and colonoscopy. Questionnaires were administered before and after the performance of the CTC and after the colonoscopy. The discomfort expected and experienced before and after the performance of both procedures as well as the patients’ preference for each method were evaluated. RESULTS: As regards CTC, before the procedure, 18% of the patients reported expecting little discomfort, 78%, mild discomfort, and 4%, a lot of discomfort. After the procedure, 72% of the patients reported little discomfort, 26%, mild discomfort, and only one (2%) of the patients reported a lot of discomfort. Upon completion of the colonoscopy, 86% of the patients reported their preference for CTC. The degree of colonic distention and residual amount of fluid had no influence on the patients’ preference. Conclusion: CTC was preferred to colonoscopy, with no statistical relationship with the degree of colonic distention at CTC and efficiency of bowel preparation.

Keywords: Colonoscopy; Virtual colonoscopy; Computed tomography colonography; Computed tomography; Patients’ preference; Patients’ satisfaction.

OBJECTIVE: To evaluate the accuracy and cost-effectiveness of metabolic staging (MS) with FDG-PET as compared with the conventional staging (CS) strategy in the preoperative staging of non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: A total of 95 patients with initial diagnosis of NSCLC were staged before undergoing treatment. The MS and CS results were compared with regard to treatment definition and incidence of futile thoracotomies with both strategies. RESULTS: Metabolic staging with FDG-PET upstaged 48.4% and downstaged 5.3% of the patients, and would lead to change in the treatment of 41% of cases. Thoracotomy was considered as futile in 47% of the patients with CS, and in 19% of the patients with MS. The cost of futile thoracotomies in eight patients with MS was R$ 79,720, while in 31 patients with CS it would be R$ 308,915. Just such saving in costs would be more than enough to cover the costs of all FDG-PETs (R$ 126,350) or FDG-PET/CTs (R$ 193,515) for the 95 patients. CONCLUSION: The metabolic staging with FDG-PET is more accurate than CS in patients with NSCLC. Both FDG-PET and FDG-PET/CT are cost-effective methods and their utilization is economically justifiable in the Brazilian public health system.

Keywords: Non-small cell lung cancer; FDG-PET; Staging; Cost-effectiveness.

OBJECTIVE: To analyze treatment outcomes in a consecutive series of patients submitted to endovascular treatment of thoracic aortic disease. Technical success, therapeutic success, morbimortality, rate of perioperative complications and reinterventions were taken into consideration. MATERIALS AND METHODS: The present retrospective study was developed in a reference center in the period from January 2010 to July 2011, involving patients submitted to endovascular treatment of thoracic aortic disease. The study population was divided into two groups: group 1 (G1) - true thoracic aortic aneurysms, aortic ulcer and pseudoaneurysm; group 2 (G2) - chronic type B aortic dissection. RESULTS: Out of a total of 55 patients, 29 belonged to the G1 and 26 to the G2 group. Mean ages were 66.8 ± 10 and 56.4 ± 7 years, respectively. The technical and therapeutic success reached respectively 86.3% and 68.6% in G1 and 100% and 74% in G2. The perioperative mortality rate was 10.3% in G1 and 19.3% in G2. The reintervention rate was 10.3% in G1 and 15.3% in G2. CONCLUSION: In the present study, the endovascular treatment of thoracic aortic disease proved to be a feasible method associated with acceptable rate of complications.

Keywords: Aneurysm; Vascular graft; Atherosclerosis.

OBJECTIVE: To identify and evaluate the prevalence of congenital central nervous system (CNS) malformations and associated defects diagnosed by obstetric ultrasonography. MATERIALS AND METHODS: Observational, descriptive, crosssectional study developed in an institution of reference for high-risk pregnancies. RESULTS: Congenital CNS malformations without other associated defects were present in 65.78% of cases, as follows: hydrocephalus (37.5%), myelomeningocele (15%), encephalocele (12.5%), corpus callosum agenesis (12.5%), anencephaly (12.5%), holoprosencephaly (7.5%), Dandy-Walker (7.5%), Arnold-Chiari (5.0%), hydranencephaly (5.0%), meningocele (5.0%), arachnoid cyst (2.5%). Congenital malformations of other systems were associated with such malformations, as follows: craniofacial (73.9%), orthopedic (65.2%), cardiovascular (34.8%), genitourinary (30.4%), gastrointestinal (30.4%), respiratory (8.7%), syndromic (8.7%), ophthalmologic (4.3%). The sonographic sensitivity in the study of CNS malformations was 79.4%. The rate of false-negative results was 20.5%. Oligohydramnios, present in 25% of false-negative studies, stands out among the quantifiable limitations. CONCLUSION: Obstetric ultrasonography presents good sensitivity in the screening for fetal CNS malformations, specially with the constant improvement and control of specialized methods such as Doppler and volumetric ultrasonography (3D/4D), contributing to consolidate its role as a modality of choice in this routine. Magnetic resonance imaging may play a supplementary role, providing information for an even better perinatal care.

Keywords: Congenital malformations; Central nervous system malformations; Associated malformations; Ultrasonography.

OBJECTIVE: To evaluate the role of PET/CT in the approach to patients with head and neck cancer. MATERIALS AND METHODS: Retrospective study of medical records and PET/CT images of 63 patients with head and neck cancer. RESULTS: Alterations were observed in 76% of the cases. Out of these cases, 7 (11%) were considered as false-positive, with SUV < 5.0. PET/CT demonstrated negative results in 15 cases (24%). Among the 14 cases where the method was utilized for staging, 3 (22%) had their stages changed. CONCLUSION: PET/CT has shown to be of potential value in the routine evaluation of patients with head and neck cancer, but further studies of a higher number of cases are required to define a protocol for utilization of the method.

Keywords: Emission computed tomography; Fluorodeoxyglucose 18F; Head and neck neoplasms; Neoplasm staging; Squamous cell carcinoma.

OBJECTIVE: To evaluate sonographic features associated with morbidity in patients with chronic clinical presentations of schistosomiasis mansoni, according to the protocol proposed by the World Health Organization (WHO). Materials and Methods: Two distinctive populations were evaluated: a) patients from an endemic area, and b) patients from a tertiary institution, with histopathologically confirmed periportal fibrosis. INCLUSION CRITERIA: diagnosis confirmed by parasitological stool examination for Schistosoma mansoni (Kato-Katz method). EXCLUSION CRITERIA: positive serology for HIV, HTLV-1, HBV or HCV. The Niamey protocol on ultrasonography proposed by the WHO was utilized. RESULTS:As the measures of periportal spaces were isolatedly evaluated, no alteration was observed in 21% of the tertiary institution patients with advanced disease. As all parameters of the Niamey protocol were considered, 100% of patients from the tertiary institution, with severe disease, presented advanced periportal fibrosis. In hepatosplenic patients from endemic areas, fibrosis was not identified at ultrasonography. CONCLUSION: The sonographic protocol proposed by the WHO can detect advanced periportal fibrosis in patients with severe form of disease with higher sensitivity than the isolated measurement of periportal space. The complexity involved in the sonographic identification of early stages of periportal fibrosis in endemic areas may give rise to the field of diagnostic supplementation and to a continued improvement of sonographic protocols in these areas.

Keywords: Schistosomiasis mansoni; Morbidity; Periportal fibrosis; Ultrasonography.

OBJETIVO: Este estudo teve por finalidade avaliar a perfusão miocárdica de pacientes com diabetes mellitus tipo 1 (DM1) e tipo 2 (DM2) assintomáticos, sem diagnóstico prévio de doença arterial coronariana (DAC) ou acidente vascular cerebral. MATERIAIS E MÉTODOS: Cinquenta e nove pacientes consecutivos (16 DM1, 43 DM2) foram submetidos a cintilografia de perfusão miocárdica com sestamibi-^99mTc (CPM). Foram avaliados quanto ao índice de massa corpórea, controle metabólico do diabetes, dislipidemia, terapia para o diabetes, hipertensão arterial sistêmica, nefropatia, retinopatia, neuropatia periférica, tabagismo e história familiar de DAC. RESULTADOS: CPM foi anormal em 25,4%: 12 (20,3%) com alterações de perfusão e 3 com disfunção ventricular esquerda isolada. Os mais fortes preditores de perfusão miocárdica anormal foram: idade igual ou maior a 60 anos (p = 0,017, odds ratio [OR] = 6,0), neuropatia periférica (p = 0,028, OR = 6,1), nefropatia (p = 0,031, OR = 5,6) e ECG de esforço positivo para isquemia (p = 0,049, OR = 4,08). CONCLUSÃO: A isquemia miocárdica silenciosa ocorre em mais de um em cada cinco diabéticos assintomáticos. Os mais fortes preditores de isquemia foram: idade avançada, neuropatia periférica, nefropatia, retinopatia e ECG de esforço positivo para isquemia.

Keywords: Diabetes mellitus; Cintilografia de perfusão miocárdica; Isquemia miocárdica silenciosa; Doença arterial coronariana.

OBJECTIVE: To evaluate the BI-RADS as a predictive factor of suspicion for malignancy in breast lesions by correlating radiological with histological results and calculating the positive predictive value for categories 3, 4 and 5 in a breast cancer reference center in the city of São Paulo. MATERIALS AND METHODS: Retrospective, analytical and cross-sectional study including 725 patients with mammographic and/or sonographic findings classified as BI-RADS categories 3, 4 and 5 who were referred to the authors' institution to undergo percutaneous biopsy. The tests results were reviewed and the positive predictive value was calculated by means of a specific mathematical equation. RESULTS: Positive predictive values found for categories 3, 4 and 5 were respectively the following: 0.74%, 33.08% and 92.95%, for cases submitted to ultrasound-guided biopsy, and 0.00%, 14.90% and 100% for cases submitted to stereotactic biopsy. CONCLUSION: The present study demonstrated high suspicion for malignancy in lesions classified as category 5 and low risk for category 3. As regards category 4, the need for systematic biopsies was observed.

Keywords: Breast cancer; BI-RADS; Percutaneous biopsy; Positive predictive value; Histological diagnosis.

In the recent years, with the development of ultrafast sequences, magnetic resonance imaging (MRI) has been established as a valuable diagnostic modality in body imaging. Because of improvements in speed and image quality, MRI is now ready for routine clinical use also in the study of pulmonary diseases. The main advantage of MRI of the lungs is its unique combination of morphological and functional assessment in a single imaging session. In this article, the authors review most technical aspects and suggest a protocol for performing chest MRI. The authors also describe the three major clinical indications for MRI of the lungs: staging of lung tumors; evaluation of pulmonary vascular diseases; and investigation of pulmonary abnormalities in patients who should not be exposed to radiation.

Keywords: Magnetic resonance imaging; Lung; Chest; Protocol; Sequences.

OBJECTIVE: To measure the scattered radiation dose at different positions simulating hip surgery. MATERIALS AND METHODS: We simulated fluoroscopy-assisted hip surgery in order to study the distribution of scattered radiation in the operating room. To simulate the patient, we used a anthropomorphic whole-body phantom, and we used an X-ray-specific detector to quantify the radiation. Radiographs were obtained with a mobile C-arm X-ray system in continuous scan mode, with the tube at 0° (configuration 1) or 90° (configuration 2). The operating parameters employed (voltage, current, and exposure time) were determined by a statistical analysis based on the observation of orthopedic surgical procedures involving the hip. RESULTS: For all measurements, higher exposures were observed in configuration 2. In the measurements obtained as a function of height, the maximum dose rates observed were 1.167 (± 0.023) µSv/s and 2.278 (± 0.023) µSv/s in configurations 1 and 2, respectively, corresponding to the chest level of health care professionals within the operating room. Proximal to the patient, the maximum values were recorded in the position occupied by the surgeon. CONCLUSION: We can conclude that, in the scenario under study, health care professionals workers are exposed to low levels of radiation, and that those levels can be reduced through the use of personal protective equipment.

Keywords: Radiation, ionizing; Operating rooms; Scattering, radiation; Radiation protection; Radiology, interventional.