OBJECTIVE: To evaluate the frequency of hypervascularization by visualizing vascular structures inside or around bone metastases from renal cell carcinoma. MATERIALS AND METHODS: Magnetic resonance imaging studies of 13 untreated patients with diagnosis of renal cell carcinoma and 15 metastatic bone lesions were retrospectively evaluated. RESULTS: Signs of hypervascularization were found in 12 of the 15 bone lesions (80%), 6 of them localized in the lumbar spine, 3 in the hip, 3 in the thoracic spine, 1 in the ulna and 1 in the tibia. CONCLUSION: The high frequency of hypervascularization of bone metastases from renal cell carcinoma found in the present study may suggest that the renal etiology is a useful parameter in the evaluation of a usual clinical presentation of a single bone lesion with unknown primary neoplasm.

Keywords: Bone metastases, Renal cell carcinoma, Magnetic resonance imaging, Hypervascularization

OBJECTIVE: To determine the incidence of most significant radiological findings of paracoccidioidomycosis and to verify its possible variants. MATERIALS AND METHODS: One hundred and seventy-three cases of paracoccidioidomycosis presented between 1970 and 1980 were reviewed, including their radiological workup reanalysis by at least two experienced radiologists. RESULTS: Ninety-four cases were pulmonary only and 38 were pulmonary associated with ganglial, visceral and osseous lesions or in association with tuberculosis. There was no pulmonary involvement in 41 cases, presenting small bowel, viscera, bone lesions, or a combination of these. Most significant radiological findings in cases of pulmonary involvement were bilateral, diffuse reticular and nodular interstitial infiltrate, followed by the diffuse bilateral alveolar form. Visceral and gastrointestinal tract lesions presented predominantly with liver, jejunum and ileum involvement. Lymph nodal involvement was predominantly diffuse, abdominal or peripheral. In bones, osteolytic lesions affected predominantly long bones and clavicle. CONCLUSION: Paracoccidioidomycosis is a granulomatous disease commonly found in Brazil, primarily affecting lungs, caused by inhalation of fungus spores. Other rare or less frequent forms of the disease should be taken into consideration for differential diagnosis.

Keywords: Paracoccidioidomycosis, Granulomatous disease

OBJECTIVE: To review and evaluate the patterns of imaging examinations findings of lung disease in patients with systemic sclerosis. MATERIALS AND METHODS: Plain x-rays and high-resolution computed tomography studies of 23 patients with systemic sclerosis were retrospectively analyzed. RESULTS: At plain x-rays, pulmonary disease with reticular pattern had higher prevalence, appearing in 18 patients (78.2%). High-resolution computed tomography showed lung involvement in the whole group of patients, with honeycombing in nine patients (39.1%), ground-glass opacities associated with reticular opacities in eight patients (34.7%), predominance of reticular opacities in five (21.7%) and only ground-glass opacities in one patient (4.3%). CONCLUSION: The pattern of abnormal findings at high-resolution computed tomography presents high correlation with histopathologic findings, differentiating inflammatory patterns from fibrotic ones, being the first associated with a better therapeutic response. We have observed abnormalities suggestive of fibrosis in most cases (honeycombing and reticular opacities corresponding to 60.8%), but with a great part of cases showing patterns suggestive of an inflammatory process.

Keywords: Computed tomography, Interstitial lung disease, Systemic sclerosis

Premature ossification of skull's sutures and its effects on the shape and appearance of the head was first reviewed in 1858 by Virchow, who named it craniosynostosis. When there is abnormal configuration of the skull, radiological evaluation must be done in order to characterize the deformity and to guide surgical corrective procedures. It is well known that a significant improvement is seen in children with early diagnosis and surgical intervention. Computed tomography 3-D reconstructions allow the evaluation of the degree of involvement of each suture and associated facial and intracranial anomalies. In this pictorial review we illustrate the image findings and discuss the nomenclature and the anomalies associated with the several types of primary craniosynostosis.

Keywords: Scaphocephaly, Plagiocephaly, Brachycephaly, Computed tomography

OBJECTIVE: To characterize interstitial lesions in anterior-posterior chest X-rays based on the analysis of textural statistical features that allow the detection of abnormalities with diffuse pattern. MATERIALS AND METHODS: Image analysis begins with the semiautomatic segmentation of the lungs, marking the external contour of the lung manually followed by an automatic division of each lung in six regions. The data base of images used in this study consisted of 482 regions obtained from examinations in which lesions were detected and 324 regions from normal examinations. Textural features were automatically extracted from each area and the selection of the best set of features was made based on the Jeffries-Matusita distance. The regions were classified as normal or suspected using the k nearest-neighbor method and half-half, and cross-correlation methodologies were used for training the classifier. RESULTS: Results were assessed based on the value of the area under the ROC (receiver operating characteristic) curve that indicates an ideal response for an area equal to 1. The results showed an area under the ROC curve (A Z) of 0.887, sensitivity of 0.804, and specificity of 0.793. CONCLUSION: These results indicate that the implemented system has a good potential for computer-aided diagnosis of interstitial lung lesions.

Keywords: Computer-aided diagnosis, Interstitial lung lesions, Texture characteristics, Pattern recognition

Fibrolipomatous hamartoma of nerve and macrodystrophia lipomatosa are rare conditions that present characteristic imaging findings. The plain films, magnetic resonance imaging studies and medical records of four patients were reviewed. The lesion was resected in one patient allowing histological confirmation of the diagnosis. Diagnosis was based on imaging and clinical findings in three patients who had unavailable biopsy data. We describe two cases of isolated macrodystrophia lipomatosa, one case of fibrolipomatous hamartoma and one case where both conditions were found. In the macrodystrophia lipomatosa cases plain films demonstrated enlargement of osseous and soft tissue structures in the affected limbs, with fatty streaks interspersed along the muscle fibers. The median nerve was affected in the cases of fibrolipomatous hamartoma. Magnetic resonance imaging findings included nerve fascicle thickening characterized by low signal on both T1 and T2-weighted sequences, and surrounding fat, which appears as high signal on T1 and low signal on T2-weighted sequences with fat saturation. Both nerves had a "coaxial cable" appearance on axial images. The fibrolipomatous hamartoma extended to the nerve branches, which is a typical finding. The typical imaging findings of macrodystrophia lipomatosa and fibrolipomatous hamartoma of nerve, particularly at magnetic resonance imaging examination, allowed a reliable diagnosis of these frequently coexistent conditions.

Keywords: Macrodystrophia lipomatosa, Fibrolipomatous hamartoma, Magnetic resonance imaging, Peripheral nerve disease, Median nerve

The objective of the present essay was to encourage a careful evaluation of periosteal reactions on magnetic resonance images. The initial approach to bone lesions is made by conventional radiography and, based on the imaging findings, periosteal reactions are classified into classical subtypes. Although magnetic resonance imaging is considered as the gold standard for local staging of bone tumors, the utilization of such method in the study of periosteal reactions related to focal bone lesions has been poorly emphasized, with relatively few studies approaching this subject. The literature review revealed a study describing an experimental animal model of osteomyelitis suggesting that magnetic resonance imaging is superior to other imaging methods in the early identification of periosteal reactions. Another study has suggested a good correlation between conventional radiography and magnetic resonance imaging in the identification and classification of periosteal reactions in cases of osteosarcoma. The present essay illustrates cases of periosteal reactions observed at magnetic resonance imaging in correlation with findings of conventional radiography or other imaging methods.

Keywords: Periostitis; Bone neoplasm; Magnetic resonance imaging.

Inferior vena cava anomalies are rare, occurring in up to 8.7% of the population, as left renal vein anomalies are considered. The inferior vena cava develops from the sixth to the eighth gestational weeks, originating from three paired embryonic veins, namely the subcardinal, supracardinal and postcardinal veins. This complex ontogenesis of the inferior vena cava, with multiple anastomoses between the pairs of embryonic veins, leads to a number of anatomic variations in the venous return from the abdomen and lower limbs. Some of such variations have significant clinical and surgical implications related to other cardiovascular anomalies and in some cases associated with venous thrombosis of lower limbs, particularly in young adults. The authors reviewed images of ten patients with inferior vena cava anomalies, three of them with deep venous thrombosis. The authors highlight the major findings of inferior vena cava anomalies at multidetector computed tomography and magnetic resonance imaging, correlating them the embryonic development and demonstrating the main alternative pathways for venous drainage. The knowledge on the inferior vena cava anomalies is critical in the assessment of abdominal images to avoid misdiagnosis and to indicate the possibility of associated anomalies, besides clinical and surgical implications.

Keywords: Inferior vena cava; Congenital abnormalities; Venous thrombosis.

OBJECTIVE: To propose a protocol for pulmonary angiography using 64-slice multidetector computed tomography (64-MDCT) with 50 mL of iodinated contrast material, in an unselected patient population, as well as to evaluate vascular enhancement and image quality. MATERIALS AND METHODS: We evaluated 29 patients (22-86 years of age). The body mass index ranged from 19.0 kg/m² to 41.8 kg/m². Patients underwent pulmonary CT angiography in a 64-MDCT scanner, receiving 50 mL of iodinated contrast material via venous access at a rate of 4.5 mL/s. Bolus tracking was applied in the superior vena cava. Two experienced radiologists assessed image quality and vascular enhancement. RESULTS: The mean density was 382 Hounsfield units (HU) for the pulmonary trunk; 379 and 377 HU for the right and left main pulmonary arteries, respectively; and 346 and 364 HU for the right and left inferior pulmonary arteries, respectively. In all patients, subsegmental arteries were analyzed. There were streak artifacts from contrast material in the superior vena cava in all patients. However, those artifacts did not impair the image analysis. CONCLUSION: Our findings suggest that pulmonary angiography using 64-MDCT with 50 mL of iodinated contrast can produce high quality images in unselected patient populations.

Keywords: Tomography, X-ray computed; Contrast media; Angiography; Pulmonary embolism.