OBJECTIVE: To develop a double-faced plane-parallel ionization chamber for measurement of air kerma and air kerma rate in X-radiation fields utilized in conventional radiography and mammography. MATERIALS AND METHODS: The chamber has entrance windows made of aluminized polyester film, inner and guard electrodes of aluminum at one side (face A) and graphite at the other side (face G). The present study evaluated operational characteristics as regards response linearity, angular and energy dependence. RESULTS: The linearity of response was 0.86% for face A and 0.92% for face G. For radiation incidence angles, of 0° to ± 5°, the response variation was less than 0.8% for both faces of the chamber. The energy dependence of response was 0.8% for face A on X-ray qualities for conventional radiography, and 2.4% for the face G of the chamber on X-ray qualities for mammography. CONCLUSION: This chamber can be utilized on a routine basis for measurement of air kerma and air kerma rate in X-ray beams utilized in conventional radiography and mammography.

Keywords: Conventional radiography, Mammography, Quality control, Ionization chamber

Intrathoracic manifestations of collagen vascular diseases are very common. The frequency of intrathoracic manifestations and the pattern of abnormality are variable depending on the type of collagen vascular disease and may simultaneously involve one or more of the following: lung parenchyma, airways, pulmonary vessels, pericardium, and pleura. Most significant manifestations include diffuse interstitial pneumonia and pulmonary hypertension which together represent the main causes of morbidity and mortality of these patients. Pulmonary, airway and pleural involvement may also be secondary to the therapy adopted for management of the disease, or result from bacterial pneumonia or opportunistic infection. In the present review, the authors summarize the main intrathoracic manifestations of collagen vascular diseases and the differential diagnosis on high-resolution chest computed tomography.

Keywords: Lung, Collagen vascular disease, Interstitial pneumonia, Pulmonary hypertension, Computed tomography

Interstitial calcinosis is an uncommon condition in which there is either localized or widely disseminated deposition of calcium in the skin, subcutaneous tissues, muscles, and tendons. Calcinosis is often associated with collagen diseases, scleroderma and dermatomyositis. The authors report a case of interstitial calcinosis associated with dermatomyositis studied with conventional radiograph, ultrasound and magnetic resonance imaging, and correlate the imaging findings with the results of surgical pathology gross examination.

Keywords: Calcinosis, Interstitial calcinosis, Dermatomyositis, Conventional radiograph, Ultrasound, Magnetic resonance imaging

OBJECTIVE: To review clinical and radiographic findings in patients with histologically confirmed giant cell tumor of bone. MATERIALS AND METHODS: Clinical and radiological data of 115 patients with giant cell tumor of bone were analyzed. RESULTS: Of the evaluated cases, 57.4% (66) were female and 80% (92) were white. The patients were 30 years old in average and the most common site of the lesions was the distal femoral metaphysis, in 22.6% (26). The most common radiographic aspect was a purely lytic lesion, in 63.7% (51) of the cases. CONCLUSION: Giant cell tumor of bone is not an uncommon tumor, predominant in the white race, with radiological findings well established.

Keywords: Conventional radiology, Giant cell tumor of bone, Bone neoplasms

OBJECTIVE: This study focuses on the biochemical response of the following variables: prostate volume, prostate-specific antigen (PSA) value, Gleason scores, staging, the risk of the disease, and hormonotherapy. MATERIALS AND METHODS: In the period between February of 1998 and July of 2001, 46 patients with prostate cancer were treated with radiotherapy, in a combination of teletherapy and high-dose rate brachytherapy (HDR). The age ranged from 51 to 79 years (averaging 66.4 years). T1c stage was the most frequent one: 30 (65%). The Gleason score was below 7 in 78% of the patients. PSA ranged from 3.4 to 33.3, being below 10 in 39% of the cases. The average prostatic volume was 32.3cc. Twenty-eight percent of the patients received hormonotherapy. Teletherapy dose ranged from 45 to 50.4 Gy, associated to four fractions of 4 Gy of HDR. RESULTS: The follow-up period varied from 6 to 43 months. Four patients missed the follow-up and four died (one due to the disease). Out of the 39 patients that were analyzed, 76% presented a less than 1.5 PSA. None of the analyzed variables were found to be of statistical significance (p>0.05) regarding biochemical control. CONCLUSION: The use of HDR brachytherapy was found to be effective in the treatment of prostate cancer and, in this study, the variables considered as prognostic factors did not interfere in the biochemical control.

Keywords: Prostate cancer, Brachytherapy, Interstitial radiotherapy

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

The recognition and differential diagnosis of the various patterns of abnormality seen on high-resolution computed tomography (HRCT) are important in the evaluation of patients with chronic insterstitial lung diseases. Various patterns of abnormality have been described in the literature, which sometimes are overlapped. Distinction between the various patterns can be difficult particularly for residents and radiologists who are not familiarized with these images. The authors illustrate the characteristic patterns of abnormality seen in chronic interstitial lung diseases and propose a simple interpretation algorithm based on the pattern and distribution of the findings. The algorithm includes the six main patterns of abnormality seen on HRCT: septal lines, reticular pattern, cystic pattern, nodular pattern, ground-glass opacities and consolidation.

Keywords: Interstitial lung disease, Lungs, Lung diseases, High-resolution computed tomography

OBJECTIVE: To review the clinical and radiographic findings in patients with histologically confirmed Ewing's sarcoma. MATERIALS AND METHODS: Clinical and radiological (whenever available) data of 226 patients with Ewing's sarcoma of the bone were analyzed. RESULTS: Of the evaluated cases, 61.5% (139) were male and 83.7% (189) were white. The average age was 14 years old and the most common site of the lesions was the iliac bone, seen in 13.7% (31) of the cases. The most common radiological findings were lytic lesion with periosteal reaction, seen in 32.7% (74) of the patients. CONCLUSION: Ewing's sarcoma of bone is an aggressive neoplasm, occurring mainly in the second decade of life, which main radiological findings are lytic lesions with periosteal reaction, typical characteristic of aggressive lesions.

Keywords: Conventional radiology, Ewing's sarcoma, Bone neoplasms

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

The authors report a case of a 24 year-old female patient with a three-month history of pain and enlargement of the left halux. Ultrasound showed a heterogeneous, hypoechoic solid soft tissue mass with cystic areas and calcification in the dorsum of the left halux. A tendinous structure was identified within the lesion but no evidence of involvement of adjacent osseous structures was found. Doppler ultrasound revealed central and peripheral hypervascularization of the lesion. Magnetic resonance imaging demonstrated a solid soft tissue mass containing a tendinous structure. The lesion appeared as an intermediate signal intensity structure on T1 images, high signal intensity on T2 images, and showed marked enhancement after intravenous administration of gadolinium. No osseous lesions were identified. The patient was submitted to surgical resection of the lesion in the dorsum of the left halux and the pathology results revealed a monophasic fibrous synovial sarcoma.

Keywords: Synovial sarcomas, Soft-tissue tumors, Ultra-sonography, Magnetic resonance imaging

The purpose of this study is to report the main high-resolution computed tomography findings of two patients with lymphocytic interstitial pneumonia. High-resolution computed tomography findings were correlated with pathology findings of material obtained from open biopsies. One patient had diffuse ground glass opacities seen on high-resolution computed tomography whereas the other patient had peribroncovascular thickening. Anatomopathology studies showed that the main pattern was polyclonal lymphocyte interstitial infiltration, particularly along alveolar septa. The current study demonstrated a close correlation between high-resolution computed tomography and anatomopathology findings.

Keywords: Lymphocytic interstitial pneumonia, High-resolution computed tomography, Anatomopathology

Pulmonary interstitial emphysema is a rare condition that generally affects low-weight preterm infants submitted to mechanical ventilation. The prognosis is variable, depending on early diagnosis and treatment. The radiologist plays a key role in this scenario. The authors report a case of persistent pulmonary interstitial emphysema, describing the main characteristics of such entity.

Keywords: Pulmonary interstitial emphysema; Newborns; Mechanical ventilation.

OBJECTIVE: To analyze the computed tomography (CT) findings of lymphocytic interstitial pneumonia (LIP). MATERIALS AND METHODS: We retrospectively reviewed the clinical and CT findings of 36 patients with LIP, including 25 women and 11 men, with a mean age of 52.5 years (age range, 22–78 years). RESULTS: The main associated diseases with LIP were Sjögren syndrome (42%), human immunodeficiency virus infection (17%), amyloidosis (17%), Sjögren syndrome associated with secondary amyloidosis (11%), idiopathic (8%), and systemic lupus erythematosus (5%). The predominant CT abnormalities were multiple cystic airspaces (n = 35), small nodules (n = 15), ground-glass opacities (n = 13), bronchiectasis and/or bronchiolectasis (n = 8), and thickening of the bronchovascular bundles (n = 8). Other CT findings included reticular opacities (n = 7), calcified nodules (n = 4), airspace consolidation (n = 4), emphysema (n = 3), honeycombing (n = 3), lymph node enlargement (n = 2), mosaic attenuation pattern (n = 1), and cavitated nodules (n = 1). CONCLUSION: The main CT findings of LIP were multiple cysts, small nodules, and ground-glass opacities.

Keywords: Lymphocytic interstitial pneumonia; Lung cysts; Computed tomography.

Soft-tissue calcifications are extremely common. Because the imaging findings are nonspecific, soft-tissue calcifications are often problematic for radiologists, sometimes prompting unnecessary interventions. In addition, the nomenclature is quite confusing. Classically, soft-tissue calcifications are divided into four categories, by mechanism of formation—dystrophic, iatrogenic, metastatic, and idiopathic—depending on the clinical and biochemical correlation. However, it is also possible to classify such calcifications by compartment, and that classification can be quite useful in the radiological diagnostic assessment. In this article, we illustrate the main causes of soft-tissue calcifications, organizing them according to their anatomical and pathophysiological aspects, thus narrowing the differential diagnosis.

Keywords: Calcinosis/diagnostic imaging; Radiography; Diagnosis, differential.

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.