OBJECTIVE: The present field research was aimed at identifying sonographic and hemodynamic findings indicative of the presence of schistosomiasis mansoni in endemic areas. MATERIALS AND METHODS: Doppler sonography was performed in 554 patients with schistosomiasis in three areas with different endemicity levels: low (n = 109), medium (n = 255) and high endemicity (n = 190). The World Health Organization (Niamey Working Group, 2000) protocol was adopted for sonographic evaluation. Doppler study included portal vessels, hepatic and splenic arteries, hepatic veins and collateral vessels. RESULTS: A significant correlation was observed between the frequency of sonographic findings, except for left lobe hypertrophy, and the areas endemicity levels. Altered hepatic veins flow pattern was observed in 23.7% of cases, such abnormality being related to the presence and intensity of periportal thickening. Hepatic arteries did not present any alteration as related to the evaluated parameters. Collateral vessels were identified only in the patients from the high-endemicity area. The splenic artery presented alterations (increase in caliber, flow velocity and resistive index), most frequently in the high-endemicity area, with significant difference between groups. CONCLUSION: Doppler sonography has shown to be a relevant auxiliary tool in the study of the morbidity related to schistosomiasis mansoni, contributing for a more accurate description of the disease profile in endemic areas.

Keywords: Schistosomiasis mansoni, Doppler sonography

OBJECTIVE: To describe epidemiological, clinical and magnetic resonance imaging findings of osteonecrosis in the distal femur and proximal tibia. MATERIALS AND METHODS: Evaluation of 19 patients (12 women and 7 men), with no previous history of causative factors, with magnetic resonance imaging findings suggestive of osteonecrosis in the tibial plateau or femoral condyle. RESULTS: Osteochondral abnormalities were observed in 63.1% of the cases; in 73.6% of them, such abnormality was associated with ipsilateral meniscal lesion. Also, a significant association with bone marrow edema (grade III in 16 cases) was observed. CONCLUSION: Magnetic resonance imaging has demonstrated to be a noninvasive method with good sensitivity in the diagnosis of knee osteonecrosis as well as of associated lesions which are most frequently found in women (63% of cases).

Keywords: Osteonecrosis, Magnetic resonance imaging, Subchondral abnormalities

OBJECTIVE: To determine reference values for placental volume at 7 to 10 + 6 weeks of gestation by means of three-dimensional ultrasonography with the XI VOCAL (eXtended Imaging Virtual Organ Computer-aided Analysis) method. MATERIALS AND METHODS: A cross-sectional study was developed with 70 pregnant women at 7 to 10 + 6 weeks of gestation. The XI VOCAL method with ten sequential adjacent planes was utilized in the volume calculations. Means, medians, standard deviation, minimum and maximum values for placental volume were calculated. A scatter plot adjusted by the determination coefficient (R²) was constructed to correlate placental volume and gestational age. RESULTS: Mean placental volume ranged from 4.6 cm³ (2.6-8.6 cm³) to 28.9 cm³ (11.4-66.9 cm³). The placental volume (PV) has shown to be highly correlated with the gestational age (GA) and the best fit equation was [PV = exp(0.582 × GA + 0.063); R² = 0.82]. CONCLUSION: Reference values for placental volume in the first gestational trimester were determined with the XI VOCAL method.

Keywords: Early placental phase, First trimester of pregnancy, Gestational age, Organ volume, Three-dimensional imaging

OBJECTIVE: To evaluate the time required to achieve maximum brachial artery dilation by means of flow-mediated dilation, as well as the differences in such dilation as four groups of smoking and nonsmoking pregnant and non-pregnant women are compared. MATERIALS AND METHODS: Cross-sectional study where the brachial artery diameter was measured considering four time spans following pressoric stimulus (30, 60, 90 and 120 seconds) in four groups of women in the age range between 20 and 30 years as follows: nonsmoking pregnant women (n = 47) and smoking pregnant women (n = 33) with gestational age between 24 and 28 weeks, nonsmoking (n = 34) and smoking (n = 19) non-pregnant women. RESULTS: The evaluation of dilation of the brachial artery at the different time spans following pressoric stimulus demonstrated maximum dilation for all the groups at "60 seconds" following the cuff deflation (p < 0.01). Brachial artery flow-mediated dilation was greater among nonsmoking pregnant women as compared with smoking ones (p = 0.03), as well as in the group of nonsmoking, non-pregnant women as compared with the smoking ones (p = 0.03). CONCLUSION: The smoking habit does not interfere in the time span required to achieve maximum brachial artery dilation.

Keywords: Ultrasonography, Endothelium, Endothelial function, Pregnant women, Smokers

OBJECTIVE: The present study was aimed at evaluating the BI-RADS® classification accuracy in mammography. Additionally, the frequency of different findings was described and the interobserver agreement was evaluated. MATERIALS AND METHODS: Mammographic images of 115 patients were independently and blindly reviewed by two specialists in compliance with BI-RADS recommendations, and later compared with histological data. The BI-RADS accuracy in mammography was evaluated. The interobserver agreement was analyzed with the Cohen's kappa (κ) test, and the differences between groups were evaluated with the chi-squared test. RESULTS: The present study demonstrated that the mammographic accuracy ranged from 75% to 62% in the differentiation between benign and malignant lesions with the utilization of the BI-RADS classification. Statistically significant interobserver agreement was observed in the description of masses margins (κ= 0.66). A low agreement rate was identified in the description of masses borders (shape) (κ= 0.40) and calcifications, both in relation to their distribution (κ= 0.24) and morphology (κ= 0.36). CONCLUSION: The present study demonstrated the BI-RADS accuracy in the differentiation between benign and malignant lesions. The interobserver agreement was poor in the analysis of calcifications morphology and distribution, but a progressive increase in the positive predictive values was observed in the subcategory 4.

Keywords: Breast cancer, Mammography, Histopathology, Accuracy, BI-RADS, Ultrasonography

OBJECTIVE: To demonstrate the knowledge of mammogram readers working in the public healthcare system in the State of Rio de Janeiro, RJ, Brazil, and to evaluate their progress in the early diagnosis of breast cancer after a training course specifically developed for medical professionals . MATERIALS AND METHODS: A group of 53 physicians with experience in mammography reports were invited. A pre-test was given to assess their initial knowledge level. Afterwards, they were trained by experts mammographers, and for final conclusion, requested to take a post-test for comparison and evaluation of gained knowledge. RESULTS: The course, with emphasis on theoretical classes, has not resulted in a significant improvement on the quality of mammogram reading, highlighting the persistence of errors in morphological description of fundamental lesions of the breast, in the classification of such lesions according to the BI-RADS®, besides the lack of coherence between the BI-RADS classification and follow-up recommendation as observed in both the pre- and post-test. CONCLUSION: The authors conclude that the mammogram readers have demonstrated insufficient knowledge in relation to early imaging diagnosis of breast cancer, and that the theoretical training has not resulted in a significant improvement on the quality of mammogram reading.

Keywords: Quality, Mammographic diagnosis, Technical parameters

OBJECTIVE: To investigate the utilization of text mining technique for evaluating the informational quality of electronic mammographic reports considering adherence to the BI-RADS® lexicon as a quality parameter. MATERIALS AND METHODS: A total of 22,247 mammography reports of the period between January, 2000 and June, 2006 were collected from the radiology information database of Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, SP, Brazil. Two experiments were undertaken - experiment 1 to evaluate the accuracy in the adoption of the lexicon terms (text mining method specificity), and experiment 2 to identify all and any attempt to utilize or refer to the lexicon (text mining method sensitivity). RESULTS: Experiment 1: variation between 11% and 61% in reports including lexicon terms in their conclusion, randomly distributed over time since 2001. Experiment 2: variation between 44% and 100% in reports that somehow refer to the lexicon in their conclusion. CONCLUSION: Results indicate a good potential for text mining tool application for assessing the quality of information included in electronic mammography reports.

Keywords: Mammography, BI-RADS, Information theory, Medical information technology

OBJECTIVE: Vacuum-assisted biopsy is the percutaneous technique of breast biopsy with the lowest underestimation rate. However, the cost of such procedure is high and currently there is a considerable interest in developing less expensive techniques. The present study was aimed at testing a less expensive device for vacuum-assisted biopsy of breast microcalcifications. MATERIALS AND METHODS: Thirty-five patients with clustered microcalcifications classified as BI-RADS® 4 or 5 were submitted to biopsy. Collected specimen appropriateness, difficulties in the reinsertion of the cannula and number of biopsy passes were evaluated. RESULTS: Successful specimens collection was achieved in all of the patients. Histo-radiological disagreement, difficulties in the cannula reinsertion or severe complications were not observed. CONCLUSION: The authors conclude that the method is effective in terms of specimens appropriateness and cost-benefit ratio as compared with of biopsy techniques for breast microcalcifications. Such findings are compatible with data reported in the literature.

Keywords: Breast biopsy, Vacuum-assisted biopsy, Mammotomy, Mammography, Microcalcifications, Vacora

OBJECTIVE: This study was aimed at evaluating the influence of the energy dependence of thermoluminescent materials on the determination of entrance skin dose in patients submitted to conventional radiographic studies (general radiology, mammography and dental radiology). MATERIALS AND METHODS: Three different thermoluminescent materials were utilized: LiF:Mg,Ti, LiF:Mg,Cu,P and CaSO4:Dy. These materials were exposed to standardized sources of X and gamma radiation and clinical X-ray beams. RESULTS: Calibration and energy dependence curves were obtained. All the materials showed a linear response as a function of the air kerma. As far as energy dependence is concerned, the CaSO4:Dy and LiF:Mg,Ti samples showed the greatest variation on thermoluminescent responses as a function of the effective radiation beam. CONCLUSION: The tested materials showed an appropriate performance for detecting X radiation on standard and clinical X-ray beams. Although CaSO4:Dy and LiF:Mg,Ti samples present a significant energy dependence in the considered energy range, these materials can be utilized for measuring entrance skin doses, provided appropriate correction factors are applied.

Keywords: Thermoluminescent dosimeters, X-ray, Radiation protection, Entrance skin dose

OBJECTIVE: To calculate spectra of cobalt-60 beam at water depth and correction factors for absorbed dose measurements obtained with lithium fluoride thermoluminescent dosimeters using Monte Carlo simulation. MATERIALS AND METHODS: The simulations of secondary spectra of clinical cobalt-60 sources were performed with the PENELOPE Monte Carlo code at different water depths. Experimental measurements of deep doses were obtained with thermoluminescent dosimeters and ionization chamber under reference conditions for radiotherapy. Correction factors for the thermoluminescent dosimeters detectors were obtained through the ratio between the relative energy absorption for the low energy spectrum and the total spectrum. RESULTS: Deep spectral analysis has demonstrated the presence of secondary low-energy spectra responsible for a significant portion of the dose deposition. Discrepancies of 3.2% were observed among the doses measured with ionization chamber and thermoluminescent dosimeters. The adoption of correction factors has allowed a reduction in the discrepancy among absorbed doses to a maximum of 0.3%. CONCLUSION: Simulated spectra allow the calculation of correction factors for reading of thermoluminescent dosimeters utilized in the measurement of deep doses, contributing for the reduction of uncertainties associated with quality control of clinical beams in radiotherapy.

Keywords: Monte Carlo simulation, Radiotherapy, Spectrometry, Quality control, Thermoluminescent dosimetry, TLD

Cerebrotendinous xanthomatosis is a rare genetic disorder characterized by a decrease in activity of the hepatic sterol 27-hydroxylase involved in the cholesterol metabolism and excretion. Consequently, lipid (cholesterol/cholestanol) deposition is observed in different regions of the body, especially tendons, central nervous system and eye lens. The present report describes the cases of two sisters affected by this disease, highlighting the main imaging findings.

Keywords: Cerebrotendinous xanthomatosis, Xanthomatosis, Hypercholesterolemia, Magnetic resonance imaging, Computed tomography

The present article reports the case of a 14-year-old male patient who developed acute chest pain following increased vocal effort during a soccer game. Chest radiography and computed tomography demonstrated pneudomediastinum with small bilateral pneumothorax. Clinical, laboratory and radiological studies did not demonstrate any predisposing factor, and the case was classified as spontaneous pneudomediastinum.

Keywords: Spontaneous pneumomediastinum, Mediastinal emphysema, Computed tomography, Vocal effort, Chest