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1.  The importance of the reviewers 
Radiologia Brasileira  2015;48(3):V.
PMCID: PMC4492562  PMID: 26185353
2.  Whole-body magnetic resonance imaging in children: state of the art* 
Radiologia Brasileira  2015;48(2):111-120.
Whole-body imaging in children was classically performed with radiography, positron-emission tomography, either combined or not with computed tomography, the latter with the disadvantage of exposure to ionizing radiation. Whole-body magnetic resonance imaging (MRI), in association with the recently developed metabolic and functional techniques such as diffusion-weighted imaging, has brought the advantage of a comprehensive evaluation of pediatric patients without the risks inherent to ionizing radiation usually present in other conventional imaging methods. It is a rapid and sensitive method, particularly in pediatrics, for detecting and monitoring multifocal lesions in the body as a whole. In pediatrics, it is utilized for both oncologic and non-oncologic indications such as screening and diagnosis of tumors in patients with genetic syndromes, evaluation of disease extent and staging, evaluation of therapeutic response and post-therapy follow-up, evaluation of non neoplastic diseases such as multifocal osteomyelitis, vascular malformations and syndromes affecting multiple regions of the body. The present review was aimed at describing the major indications of whole-body MRI in pediatrics added of technical considerations.
PMCID: PMC4433302  PMID: 25987752
Magnetic resonance imaging; Whole-body MRI; Diffusion-weighted imaging; Pediatrics
4.  Catamenial pneumothorax 
Radiologia Brasileira  2015;48(2):128-129.
PMCID: PMC4433306  PMID: 25987756
6.  Hibernoma: an uncommon cause of a pleural mass 
Jornal Brasileiro de Pneumologia  2015;41(1):103-104.
PMCID: PMC4350833  PMID: 25750682
7.  Changes in Radiologia Brasileira for 2015 
Radiologia Brasileira  2015;48(1):v.
PMCID: PMC4366022  PMID: 25798016
8.  Magnetic resonance imaging of the chest in the evaluation of cancer patients: state of the art 
Radiologia Brasileira  2015;48(1):33-42.
Magnetic resonance imaging (MRI) has several advantages in the evaluation of cancer patients with thoracic lesions, including involvement of the chest wall, pleura, lungs, mediastinum, esophagus and heart. It is a quite useful tool in the diagnosis, staging, surgical planning, treatment response evaluation and follow-up of these patients. In the present review, the authors contextualize the relevance of MRI in the evaluation of thoracic lesions in cancer patients. Considering that MRI is a widely available method with high contrast and spatial resolution and without the risks associated with the use of ionizing radiation, its use combined with new techniques such as cine-MRI and functional methods such as perfusion- and diffusion-weighted imaging may be useful as an alternative tool with performance comparable or complementary to conventional radiological methods such as radiography, computed tomography and PET/CT imaging in the evaluation of patients with thoracic neoplasias.
PMCID: PMC4366027  PMID: 25798006
Magnetic resonance imaging; Diffusion-weighted imaging; Chest; Thoracic lesions; Oncology
11.  Improving CT-guided transthoracic biopsy of mediastinal lesions by diffusion-weighted magnetic resonance imaging 
Clinics  2014;69(11):787-791.
To evaluate the preliminary results obtained using diffusion-weighted magnetic resonance imaging and the apparent diffusion coefficient for planning computed tomography-guided biopsies of selected mediastinal lesions.
Eight patients with mediastinal lesions suspicious for malignancy were referred for computed tomography-guided biopsy. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient measurement were performed to assist in biopsy planning with diffusion/computed tomography fused images. We selected mediastinal lesions that could provide discordant diagnoses depending on the biopsy site, including large heterogeneous masses, lesions associated with lung atelectasis or consolidation, lesions involving large mediastinal vessels and lesions for which the results of biopsy using other methods and histopathological examination were divergent from the clinical and radiological suspicion.
In all cases, the biopsy needle was successfully directed to areas of higher signal intensity on diffusion-weighted sequences and the lowest apparent diffusion coefficient within the lesion (mean, 0.8 [range, 0.6–1.1]×10-3 mm2/s), suggesting high cellularity. All biopsies provided adequate material for specific histopathological diagnoses of four lymphomas, two sarcomas and two thymomas.
Functional imaging tools, such as diffusion-weighted imaging and the apparent diffusion coefficient, are promising for implementation in noninvasive and imaging-guided procedures. However, additional studies are needed to confirm that mediastinal biopsy can be improved with these techniques.
PMCID: PMC4255081  PMID: 25518038
MRI-Guided Biopsy; DWI-Guided Biopsy; Mediastinal Lesion; Diagnosis; Malignancy; Tomography
12.  Which is your diagnosis? 
Radiologia Brasileira  2014;47(6):XI-XIII.
PMCID: PMC4341385  PMID: 25741128
13.  Thoracic textilomas: CT findings*  
Jornal Brasileiro de Pneumologia  2014;40(5):535-542.
The aim of this study was to analyze chest CT scans of patients with thoracic textiloma.
This was a retrospective study of 16 patients (11 men and 5 women) with surgically confirmed thoracic textiloma. The chest CT scans of those patients were evaluated by two independent observers, and discordant results were resolved by consensus.
The majority (62.5%) of the textilomas were caused by previous heart surgery. The most common symptoms were chest pain (in 68.75%) and cough (in 56.25%). In all cases, the main tomographic finding was a mass with regular contours and borders that were well-defined or partially defined. Half of the textilomas occurred in the right hemithorax and half occurred in the left. The majority (56.25%) were located in the lower third of the lung. The diameter of the mass was ≤ 10 cm in 10 cases (62.5%) and > 10 cm in the remaining 6 cases (37.5%). Most (81.25%) of the textilomas were heterogeneous in density, with signs of calcification, gas, radiopaque marker, or sponge-like material. Peripheral expansion of the mass was observed in 12 (92.3%) of the 13 patients in whom a contrast agent was used. Intraoperatively, pleural involvement was observed in 14 cases (87.5%) and pericardial involvement was observed in 2 (12.5%).
It is important to recognize the main tomographic aspects of thoracic textilomas in order to include this possibility in the differential diagnosis of chest pain and cough in patients with a history of heart or thoracic surgery, thus promoting the early identification and treatment of this postoperative complication.
PMCID: PMC4263335  PMID: 25410842
Foreign-body reaction; Tomography; spiral computed; Thoracic surgery
15.  Is DWI/ADC a Useful Tool in the Characterization of Focal Hepatic Lesions Suspected of Malignancy? 
PLoS ONE  2014;9(7):e101944.
Apparent diffusion coefficient (ADC) values calculated through magnetic resonance imaging have been proposed as a useful tool to distinguish benign from malignant liver lesions. Most studies however included simple cysts in their analysis. Liver cysts are easy to diagnose, have very high ADC values and their inclusion facilitates differentiation in the ADC values between benign and malignant liver lesions groups. We prospectively evaluated the ability of ADC values to differentiate metastatic liver lesions from all benign or only solid benign liver lesions.
Material and Methods
Sixty-seven adult cancer patients with 188 liver lesions were evaluated. Lesions were categorized as metastatic or benign throughout imaging and clinical evaluation. One hundred and five (105) metastatic lesions and 83 benign lesions including hemangiomas (37), cysts (42), adenomas (2) and focal nodular hyperplasias (2) were evaluated. ADC values were calculated for each lesion utilizing two b values (0 and 600 sec/mm2).
The average ADC value for cysts was 2.4×10−3 mm2/sec (CI: 2.1–2.6), for solid benign lesions was 1.4×10−3 mm2/sec (CI: 1.1–1.7) and for metastases was 1.0×10−3 mm2/sec (CI: 0.8–1.3). There was a difference between the ADC values of metastases and benign solid lesions (p<0.0001). With the ADC value of 1.5×10−3 mm2/sec as a cut off it is possible to distinguish metastatic from benign liver lesions, including cysts, with an accuracy of 78%. But to distinguish metastatic from benign solid liver lesions the best ADC cut off value was 1.2×10−3 mm2/sec and the accuracy drops to 71%.
ADC values proved to be helpful in the distinction between metastasis and benign solid hepatic lesions. But the exclusion of cysts in the analysis point out to a lower cut off value and lower accuracy than previously reported.
PMCID: PMC4099077  PMID: 25025151
16.  Functional imaging with diffusion-weighted MRI for lung biopsy planning: initial experience 
The purpose of this study was to evaluate the usefulness of diffusion-weighted magnetic resonance imaging (DW-MRI) and positron emission tomography/computed tomography (PET/CT) in planning transthoracic CT-guided biopsies of lung lesions.
Thirteen patients with lung lesions suspicious for malignancy underwent CT-guided biopsy. Chest DW-MRI and apparent diffusion coefficient (ADC) calculation were performed to aid biopsy planning with fused images. MRI was indicated due to large heterogeneous masses, association with lung atelectasis/consolidation/necrosis, and/or divergent results of other biopsy type and histopathology versus clinical/radiological suspicion. Eight patients underwent PET/CT to identify appropriate areas for biopsy.
Mean patient (n = 9 males) age was 59 (range, 30 to 78) years. Based on DW-MRI results, biopsies targeted the most suspicious areas within lesions. All biopsied areas showed higher DW signal intensity and lower ADCs (mean, 0.79 (range, 0.54 to 1.2) × 10−3 mm2/s), suggesting high cellularity. In patients who underwent PET/CT, areas with higher 18-fluorodeoxyglucose concentrations (standard uptake value mean, 7.7 (range, 3.6 to 13.7)) corresponded to areas of higher DW signal intensity and lower ADCs. All biopsies yielded adequate material for histopathological diagnosis.
Functional imaging is useful for lung biopsy planning. DW-MRI and PET/CT increase overall performance and enable the collection of adequate material for specific diagnosis.
PMCID: PMC4101714  PMID: 25012544
Functional imaging; MRI-guided biopsy; DWI; Transthoracic biopsy; Lung lesion; PET/CT-guided biopsy
19.  Lung in Dengue: Computed Tomography Findings 
PLoS ONE  2014;9(5):e96313.
Dengue is the most important mosquito-borne viral disease in the world. Dengue virus infection may be asymptomatic or lead to undifferentiated fever, dengue fever with or without warning signs, or severe dengue. Lower respiratory symptoms are unusual and lung-imaging data in patients with dengue are scarce.
Methodology/Principal Findings
To evaluate lung changes associated with dengue infection, we retrospectively analyzed 2,020 confirmed cases of dengue. Twenty-nine of these patients (11 females and 18 males aged 16–90 years) underwent chest computed tomography (CT), which yielded abnormal findings in 17 patients: 16 patients had pleural effusion (the sole finding in six patients) and 11 patients had pulmonary abnormalities. Lung parenchyma involvement ranged from subtle to moderate unilateral and bilateral abnormalities. The most common finding was ground-glass opacity in eight patients, followed by consolidation in six patients. Less common findings were airspace nodules (two patients), interlobular septal thickening (two patients), and peribronchovascular interstitial thickening (one patient). Lung histopathological findings in four fatal cases showed thickening of the alveolar septa, hemorrhage, and interstitial edema.
In this largest series involving the use of chest CT to evaluate lung involvement in patients with dengue, CT findings of lower respiratory tract involvement were uncommon. When abnormalities were present, pleural effusion was the most frequent finding and lung involvement was often mild or moderate and bilateral. Extensive lung abnormalities are infrequent even in severe disease and when present should lead physicians to consider other diagnostic possibilities.
PMCID: PMC4023925  PMID: 24836605
20.  CT-guided biopsy of lung lesions: defining the best needle option for a specific diagnosis 
Clinics  2014;69(5):335-340.
To evaluate the performance of fine and cutting needles in computed tomography guided-biopsy of lung lesions suspicious for malignancy and to determine which technique is the best option for a specific diagnosis.
This retrospective study reviewed the data from 362 (71.6%) patients who underwent fine-needle aspiration biopsy and from 97 (19.7%) patients who underwent cutting-needle biopsy between January 2006 and December 2011. The data concerning demographic and lesion characteristics, procedures, biopsy sample adequacy, specific diagnoses, and complications were collected. The success and complication rates of both biopsy techniques were calculated.
Cutting-needle biopsy yielded significantly higher percentages of adequate biopsy samples and specific diagnoses than did fine-needle aspiration biopsy (p<0.05). The sensitivity, specificity, and accuracy of cutting-needle biopsy were 93.8%, 97.3%, and 95.2%, respectively; those of fine-needle aspiration biopsy were 82.6%, 81.3%, and 81.8%, respectively (all p<0.05). The incidence of pneumothorax was higher for fine-needle aspiration biopsy, and that of hematoma was higher for cutting-needle biopsy (both p<0.05).
Our experience using these two techniques for computed tomography-guided percutaneous biopsy showed that cutting-needle biopsy yielded better results than did fine-needle aspiration biopsy and that there was no significant increase in complication rates to indicate the best option for specific diagnoses.
PMCID: PMC4012240  PMID: 24838899
Computed Tomography-Guided Biopsy; Lung Lesion; Neoplasm; Diagnosis; Malignancy; Tomography
21.  Which is your diagnosis? 
Radiologia Brasileira  2014;47(3):XI-XIII.
PMCID: PMC4337138  PMID: 25741084
22.  Imaging acute complications in cancer patients: what should be evaluated in the emergency setting? 
Cancer Imaging  2014;14(1):18.
Increased incidence world-wide of cancer and increased survival has also resulted in physicians seeing more complications in patients with cancer. In many cases, complications are the first manifestations of the disease. They may be insidious and develop over a period of months, or acute and manifest within minutes to days. Imaging examinations play an essential role in evaluating cancer and its complications. Plain radiography and ultrasonography (US) are generally performed initially in an urgent situation due to their wide availability, low cost, and minimal or no radiation exposure. However, depending on a patient’s symptoms, evaluation with cross-sectional imaging methods such as computed tomography (CT) and magnetic resonance imaging (MRI) is often necessary. In this review article, we discuss some of the most important acute noninfectious oncological complications for which imaging methods play an essential role in diagnosis.
PMCID: PMC4331823  PMID: 25609051
23.  Functional magnetic resonance imaging in oncology: state of the art*  
Radiologia Brasileira  2014;47(2):101-111.
In the investigation of tumors with conventional magnetic resonance imaging, both quantitative characteristics, such as size, edema, necrosis, and presence of metastases, and qualitative characteristics, such as contrast enhancement degree, are taken into consideration. However, changes in cell metabolism and tissue physiology which precede morphological changes cannot be detected by the conventional technique. The development of new magnetic resonance imaging techniques has enabled the functional assessment of the structures in order to obtain information on the different physiological processes of the tumor microenvironment, such as oxygenation levels, cellularity and vascularity. The detailed morphological study in association with the new functional imaging techniques allows for an appropriate approach to cancer patients, including the phases of diagnosis, staging, response evaluation and follow-up, with a positive impact on their quality of life and survival rate.
PMCID: PMC4337156  PMID: 25741058
Cancer imaging; Magnetic resonance imaging; Oncology; Neoplasia; Functional imaging; Diffusion

Results 1-25 (73)