Alair Augusto Sarmet Moreira Damas dos Santos

Diagnostic performance of combined cardiac MRI for detection of coronary artery disease.

OBJECTIVE To evaluate the diagnostic performance of stress perfusion cardiac MR (CMR) for detecting significant CAD (≥70% narrowing) in comparison with invasive coronary angiography (ICA) as a reference standard. METHODS Examinations of 54 patients who underwent both stress perfusion CMR and ICA for investigation of CAD between 2007 and 2009 were evaluated. The CMR protocol included dipyridamole stress and rest perfusion, stress and rest cine MRI for assessment of ventricular function and delayed gadolinium enhancement for assessment of myocardial viability and detection of infarction. CMR interpretation was performed by 2 observers blinded to the results of ICA and the clinical history. RESULTS From a total of 54 patients, 37 (68.5%) showed significant CAD in 71 coronary territories. A perfusion defect was detected in 35 patients and in 69 coronary territories. Individual stress perfusion CMR evaluation showed the highest accuracy (83%) of the CMR techniques. The combined analysis using all sequences increased the overall accuracy of CMR to 87%. CONCLUSION Combination of perfusion and cine-MR during stress/rest, associated to delayed enhancement in the same protocol improves CMRI diagnostic accuracy and sensitivity for patients with significant coronary stenosis, and may therefore be helpful for risk stratification and defining treatment strategies.

Hybrid analysis for indicating patients with breast cancer using temperature time series

Breast cancer is the most common cancer among women worldwide. Diagnosis and treatment in early stages increase cure chances. The temperature of cancerous tissue is generally higher than that of healthy surrounding tissues, making thermography an option to be considered in screening strategies of this cancer type. This paper proposes a hybrid methodology for analyzing dynamic infrared thermography in order to indicate patients with risk of breast cancer, using unsupervised and supervised machine learning techniques, which characterizes the methodology as hybrid. The dynamic infrared thermography monitors or quantitatively measures temperature changes on the examined surface, after a thermal stress. In the dynamic infrared thermography execution, a sequence of breast thermograms is generated. In the proposed methodology, this sequence is processed and analyzed by several techniques. First, the region of the breasts is segmented and the thermograms of the sequence are registered. Then, temperature time series are built and the k-means algorithm is applied on these series using various values of k. Clustering formed by k-means algorithm, for each k value, is evaluated using clustering validation indices, generating values treated as features in the classification model construction step. A data mining tool was used to solve the combined algorithm selection and hyperparameter optimization (CASH) problem in classification tasks. Besides the classification algorithm recommended by the data mining tool, classifiers based on Bayesian networks, neural networks, decision rules and decision tree were executed on the data set used for evaluation. Test results support that the proposed analysis methodology is able to indicate patients with breast cancer. Among 39 tested classification algorithms, K-Star and Bayes Net presented 100% classification accuracy. Furthermore, among the Bayes Net, multi-layer perceptron, decision table and random forest classification algorithms, an average accuracy of 95.38% was obtained.

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa presenting after chest trauma and diagnosed by cardiac magnetic resonance: a case report.

IntroductionAnnular subvalvular pseudoaneurysm is a rare example of left ventricle aneurysm described predominantly in young African people. These aneurysms are divided into two different types, namely, submitral or subaortic, with subaortic being the less frequent kind. The subaortic type is most often localized in the mitral–aortic intervalvular fibrosa. To the best of our knowledge, this is the first report of a mitral–aortic intervalvular fibrosa pseudoaneurysm associated with coarctation of the aorta, anomalous pulmonary venous return, bicuspid aortic valve and patent ductus arteriosus diagnosed by cardiovascular magnetic resonance.Case presentationWe report the case of a 15-year-old African-American boy with a history of mild chest trauma who underwent echocardiographic evaluation as part of an out-patient work up. The echocardiogram was suspicious for the presence of mitral-aortic intervalvular fibrosa pseudoaneurysm and cardiovascular magnetic resonance was then performed to better characterize this finding. In addition to confirming the presence of the aneurysm, cardiovascular magnetic resonance also revealed coarctation of the aorta, a bicuspid aortic valve, and anomalous pulmonary venous return.ConclusionIn our case, cardiovascular magnetic resonance was helpful in: (a) making a definite diagnosis of mitral–aortic intervalvular fibrosa pseudoaneurysm and its borders, which was not clear with an echocardiogram examination; and (b) illustrating additional associated congenital anomalies including the anomalous pulmonary venous return.

Telemedicine and Pediatric Radiology: A New Environment for Training, Learning, and Interactive Discussions

OBJECTIVE To report the experience of the Brazilian Program of Pediatric Teleradiology in combining teleconferencing and a virtual learning environment for services integration, collaborative research, and continuing education in pediatric radiology. MATERIALS AND METHODS We performed virtual meetings from March 2005 to October 2010 on pediatric radiology-related themes, using a combination of videoconferences and Web conferences, which were recorded and made available in an open-source software (Moodle) for reuse. RESULTS We performed 58 virtual sessions: 29 anatomical-clinical-radiological sessions, 28 on upgrading themes, and 1 virtual symposium. The average of connected points was 12 by videoconference and 39 by Web conference, and of 450 participants per event. At the time of this writing, 318 physicians and students are registered in the virtual learning environment, with a total of 14,678 accesses. CONCLUSIONS Telemedicine is being included in pediatric radiology practice, as a means for distance education, training, and continuing integration between groups.

Digitalização de filmes radiográficos com costura de imagens

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.

Linfoma adrenal primário bilateral com envolvimento do sistema nervoso central: relato de caso

The authors review the main findings of primary adrenal lymphoma on abdominal and brain computed tomography (CT) scans and brain magnetic resonance imaging (MRI), and report a rare case of a 72-year-old male patient with deterioration in mental status progressing from recent memory loss to disorientation and ultimately dementia in a period of two months. The patient was investigated using imaging methods including brain (without intravenous administration of iodinated contrast media), chest and abdomen (pre and post intravenous administration of iodinated contrast media) CT scans and brain MRI (pre and post intravenous administration of gadolinium). Brain CT scan showed slightly hyperdense nodules adjacent to the lateral ventricles. No gross abnormalities were seen on the chest CT scan. CT of the abdomen showed solid nodules on both adrenals. Brain MRI showed diffuse nodular enhancement of the ependyma of the fourth ventricle, third ventricle, frontal and temporal horns, atria and body of the lateral ventricles. Definitive diagnosis was made by immunohistochemical study of the biopsed adrenal. After a comprehensive review of the literature the authors concluded that CT and MRI are essential methods for the detection and accurate evaluation of primary adrenal lymphomas, particularly when there is involvement of the central nervous system. MRI is more sensitive in the detection of extracerebral lesions in the epidural and subdural spaces, especially after intravenous administration of gadolinium.

Seqüestro broncopulmonar intralobar: relato de caso

We report the case of a 49-year-old patient with repeated lung infections. Chest x-rays showed a mass in the posterior basal segment of the right lung. Angiotomography and 3D reconstructions showed a blood supply coming from the descending aorta. The analysis of the surgical specimen confirmed the occurrence of intralobar pulmonary sequestration with a cavitation filled with mucus.

Caseous calcification of the mitral annulus: computed tomography features.

. Nevertheless, because for-eign bodies of vegetable origin do not produce hyperintense im-ages, the diagnosis is not usually obtained by CT. Upper gas-trointestinal endoscopy is a useful tool in the study of gastric le-sions and allows the collection of material for histopathologicalevaluation. However, endoscopic biopsies are usually small andsuperficial, which can make it difficult to confirm the diagnosis ofgranuloma pulse

Leiomyoma of the breast: an uncommon tumor

1. Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. Mailing address: Richard C. Semelka, MD. UNC Department of Radiology. 101 Manning Drive CB#7510 – 2001 Old Clinic Bldg. Chapel Hill, NC 27599-7510, USA. E-mail: richsem@med.unc.edu. destruens is a locally invasive (myometrium) manifestation of complete HM that represents 13% of cases of GTD. Two percent of complete HM cases are described as choriocarcinoma, which is locally invasive and potentially metastasizing. These three entities produce peculiarly high levels of β-hCG, while placental site trophoblastic tumor causes a rise in human placental lactogen levels, and less elevated β-hCG levels. Clinical assessment is difficult early in the course of the disease, as few clinical characteristics are present to distinguish it from a normal pregnancy. Pelvic MRI is often used as a problem-solving tool in equivocal or complicated cases of GTD, especially in the first trimester, or to assess the degree of myometrial invasion and surrounding tissues. Early manifestations appear as a soft tissue cystic mass with high T2 signal intensity. In the second trimester these lesions tend to distend the endometrium giving a “cluster of grapes appearance”. Typically HMs are similar or slightly higher in T1 signal intensity than the adjacent myometrium. Contrast-enhanced MRI show areas of focal enhancement that relate to the amount of active trophoblastic tissue and also to β-hCG levels. Marked early enhancement indicates active disease in the form of viable trophoblastic tissue. In the setting of GTD, identification of myometrial invasion is crucial for diagnosis and staging. Uterine tumors associated with high serum β-hCG have a high incidence of myometrial contractions. Myometrial contractions are seen as a bulge of the myometrial wall usually along with a region of low T2 signal intensity in the myometrium. They are transient and tend to disappear on subsequent data acquisitions, as observed in our case. In the setting of endometrial tumor, radiologists should be aware of this phenomenon to avoid over-diagnosis and over-staging by misdiagnosing uterine contraction with myometrial extension or invasion. REFERENCES

A importância do apoio psicológico ao médico residente e especializando em radiologia e diagnóstico por imagem

OBJECTIVE: To highlight the relevance and necessity of implementing a service to provide psychological support to physicians specializing in radiology and imaging diagnosis. MATERIALS AND METHODS: Qualitative research with application of a questionnaire to 219 residents and trainees in radiology and imaging diagnosis, in the period between 2007 and 2009. The questionnaire included questions regarding their psychosocial profile, perception of the level of relationship with the service team, level of learning, psychological difficulties and evaluation of the prevalence of anxiety and depression symptoms according to the Hospital Anxiety and Depression Scale. RESULTS: Among the respondents, 116 (53%) were women and 103 (47%) were men. Most of them, 170 (77.6%), were in the age range between 20 and 30 years. It was observed that 51.1% of the respondents presented anxiety and 54.8%, depression symptoms. Among the respondents, 44.8% showed interest in seeking psychological assistance to address their problems. CONCLUSION: The implementation of a service to provide psychological support to residents and trainees in radiology and imaging diagnosis should be done by psychologists specialized in hospital and clinical psychology, skilled to welcome and assist them to deal with difficulties in the training, as well as in their adaptation and integration, thus contributing to reduce stress and symptoms of anxiety and depression.