OBJECTIVE: The aim of this study was to determine the normal values of the Achilles tendon thickness in the anteroposterior dimension and width in the transverse dimension in our population, correlating them with gender, age ranges, race, ABO blood group and body mass index. MATERIALS AND METHODS: Ultrasonographic examination was employed to evaluate 100 Achilles tendons of 50 healthy volunteers in order to measure the tendons thickness in the anteroposterior dimension and width in the transverse dimension. All examinations were performed by the same sonographer, using an ultrasound equipment with a 10 MHz linear transducer. RESULTS: Among the 50 volunteers studied, 25 were men and 25 were women, ranging from 20 to 52 years (average 33.9 years). The tendons average width was 13.3 ± 1.0 mm in the female group and 14.4 ± 1.4 mm in the male group; the average thickness was 5.4 ± 0.5 mm in the female group and 5.6 ± 0.6 mm in the male group. These measurements were significantly lower in the female group (p < 0.05). There was no significant correlation between the tendon measurements and the age ranges, ABO blood groups and races. The tendon width was significantly higher in the overweight body mass index group than in the normal body mass index group. CONCLUSION: Mean values found in our study differ significantly from the majority of other studies in the literature, demonstrating the importance of creating our own standards employing tables based on our population in daily clinical practice.

Keywords: Achilles tendon, Ultrasound, Anatomy, Anthropometry

OBJECTIVE: To compare the performance of low-field-strength and high-field-strength magnetic resonance imaging equipments for evaluation of the patella articular cartilage. MATERIALS AND METHODS: The study was developed using GRE 2D, GRE 3D, FSE T2, STIR sequences (low-field) and TSE T2 SPIR sequence. Each sequence has been separately analyzed for evaluation of the cartilage without knowledge of other sequences results or any patients data; the lesion was assigned a grade from 0 to 3 and had its location defined. Agreement and disagreement results were analyzed by Kappa and McNemar tests. RESULTS: Medial facet has presented low agreement index and disagreements showed to be significantly overestimated. Lateral facet has presented a reasonable agreement index and disagreement index was not significant. Medial ridge has presented a reasonable agreement index and disagreement index has showed to be underestimated. CONCLUSION: The STIR sequence versus TSE T2 SPIR sequence has presented the higher agreement index. High grade lesions are better characterized by low-field-strength magnetic resonance imaging equipment sequences. Areas of increased signal intensity make difficult the study of the patella medial facet cartilage in low-field-strength equipment.

Keywords: Magnetic resonance imaging, Skeletal - appendicular, Knee, Comparative study, Equipments, Imaging sequences

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

OBJECTIVE: To determine the role of transrectal ultrasound, especially in association with color Doppler, in the diagnosis of prostate cancer. MATERIALS AND METHODS: Eighty-four cases of patients who underwent transrectal biopsy were prospectively analyzed. In all patients, besides the traditional gray-scale sonogram, color Doppler study was performed in search of hypervascular foci. The results were compared with the histopathologic diagnosis. RESULTS: The gray-scale sonogram showed a 67.7% sensitivity, 52.8% specificity, positive predictive value of 45.6% and negative predictive value of 73.6%. The association with color Doppler increased the specificity (from 52.8% to 79.2%) and the positive predictive value (from 45.6% to 62.0%) although it has caused a decrease in the sensitivity (from 67.7% to 58.0%). Besides, the study had 32.2% of missed cancers by both methods, and these patients, although having less extensive cancers all of them were clinically significant (Gleason 6 or more). CONCLUSION: Transrectal ultrasound findings, even in association with color Doppler, are not sufficiently accurate to determine whether a patient should or not be submitted to biopsy.

Keywords: Prostate, Prostatic cancer, Transrectal ultrasound, Color Doppler, Prostate biopsy

OBJECTIVE: Our purpose was to verify the effect of changes in subject contrast, exposure time and radiation dose when different thicknesses of molybdenum (Mo) and rhodium (Rh) filters are used in mammography equipments. MATERIALS AND METHODS: Entrance skin exposure measurements were performed with an ionization chamber for different thicknesses of Mo and Rh filters. Average glandular dose was determined with a BR12 simulator (50% fat tissue and 50% glandular tissue) of different thicknesses (4 cm and 8 cm). Energies in the range of 24 to 34 kVp and Kodak MinR 2000 films were used. RESULTS: Results have evidenced data on subject contrast data, glandular dose and exposure time for different thicknesses of additional filters and different kVp values. These data have indicated an increase both in values of subject contrast and exposure time when filters thickness is increased. The glandular dose has presented a different behavior tendency for each case analyzed. Equations were defined to allow us to estimate subject contrast, glandular dose and exposure time for the cases studied. CONCLUSION: The results have made possible to define equations to assist with the evaluation of subject contrast and glandular dose behavior in simulators with 4 cm and 8 cm thicknesses and for Rh and Mo additional filters. In this way, it is possible to estimate the figure of merit (subject contrast/glandular dose ratio) to assist in the risk-benefit analysis of the cases studied.

Keywords: Mammography, Radiation exposure, External dosimetry

OBJECTIVE: Central venous access is an increasingly frequent procedure and intravenous catheter fractures and fragments embolization, although being rare, correspond to the most common intravascular foreign bodies. This study purpose is to show our experience in the removal of these foreign bodies, employing endovascular techniques. MATERIALS AND METHODS: Retrospective analysis of ten consecutive cases in the last five years, including patients with ages ranging from 9 months to 67 years. RESULTS: The procedure was successfully performed in all the cases by means of different techniques and with no complication. Most common fragments lodgement sites were: right atrium, superior vena cava and left pulmonary artery. The retrieval of these foreign bodies by means of endovascular techniques is a relatively simple procedure when compared to the surgical alternative, and has been safely and successfully performed in countless patients. The available devices have proven quite effective and, among them, the loop snare is the most versatile. CONCLUSION: The high success rate with few complications reported, even in children, allows us to say that, whenever possible, percutaneous extraction of intravascular foreign objects should be performed. Notwithstanding, familiarization with the several techniques available is essential, allowing combinations and modifications according to each situation.

Keywords: Vascular access ports, Foreign bodies, Embolism

OBJECTIVE: The objective of this study was to compare the absorbed dose to air calibration factors determined in gamma (60Co) and electron beams. MATERIALS AND METHODS: An irradiator with a 60Co source and a Varian, Clinac 2100C linear accelerator with photon and electron beams were utilized. One thimble-type and three parallel-plate ionization chambers were tested. RESULTS: The measurement systems were submitted to preliminary tests (response stability and leakage current), with quite good results. The absorbed dose to air calibration factors were determined using four measurement systems and two types of phantoms. Results were obtained in compliance with the international recommendations. CONCLUSION: Absorbed dose to air calibration factors obtained for parallel plate ionization chambers, determined in 60Co beams, at maximum, are 1.2% higher than the values obtained in high energy electron beams.

Keywords: Ionization chambers, Electron beams, Calibration of instruments

OBJECTIVE: The aim of this study was to establish a calibration methodology specific for pencil ionization chambers used in computed tomography dosimetric procedures, in compliance with the most recent recommendations. The study was developed at the Calibration Laboratory of the Instituto de Pesquisas Energéticas e Nucleares. MATERIALS AND METHODS: An industrial x-ray equipment, several types of ionization chambers, a mobile collimator (diaphragm type), and several high purity aluminum filters were utilized in this study. RESULTS: Diagnostic radiology standard irradiation fields were established according to IEC 61267 standard, and an adequate calibration procedure for pencil ionization chambers was elaborated. CONCLUSION: The appropriate calibration of pencil ionization chambers is already a reality in Brazil. The calibration procedure was defined on the basis of international standards and on a comparative study using two different methodologies.

Keywords: Pencil ionization chamber, Calibration methodologies, Standard beams

OBJECTIVE: The objective of this study was to perform a passive and time-integrated radon monitoring in several soil and water samples and indoor environments of the São Vicente, SP, rock massif with the purpose of evaluating the presence and distribution of that radioactive gas in this region. MATERIALS AND METHODS: The technique employed consisted of exposing Makrofol E-type polycarbonate plastic detectors (SSNTD), using the closed cup method, to radon emanated from ground water samples and to the gas accumulated inside indoor environments (dwellings) and inside rock cavities existing in the São Vicente rock massif. RESULTS: The radon concentration values obtained ranged from 8.1 to 36 Bq/l in natural ground waters; between 68 and 610 Bq/m³ in dwellings; from 0.41 to 3.46 kBq/m³ in soils and from 0.72 to 5.85 kBq/m³ inside rock cavities of the São Vicente rock massif. CONCLUSION: In some dwellings and in most of ground water samples, the radon concentration values found in this study have exceeded the maximum levels proposed by international agencies. Thus, intervention actions are recommended for radon dissipation in dwellings and during consumption water collection.

Keywords: Radon, Natural radioactivity, Nuclear track detectors, Environment, Uranium

In order to evaluate atypical aspects of hepatic hemangiomas at ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI), we have retrospectively analyzed 300 cases of patients diagnosed with hepatic hemangiomas by means of combined imaging studies, clinical follow-up and/or biopsy results. Based on this analysis we have selected those cases with atypical findings at one or more imaging methods or those presenting an unusual evolution such as: hypoechoic nodules at US; giant, heterogeneous hemangiomas; rapidly filling hemangiomas; calcified hemangiomas; pedunculated hemangiomas; hypointense hemangiomas at T2-weighted images; causing perfusion defect; with central scar simulating focal nodular hyperplasia; hemangiomas with adjacent abnormalities such as arterial-portal venous shunt and capsular retraction as well as hemangiomas enlarging over time. The hepatic hemangioma is the most common benign tumor affecting the liver and usually presents typical aspect. However, atypical findings should be known aiming at supporting diagnosis guidance and clinical decisions.

Keywords: Hemangioma, Liver, Atypical findings, Ultrasound, Computed tomography, Magnetic resonance imaging

Currently, computed tomography is the method of choice for assessment of paranasal sinuses, nasal fossae and their anatomical variations. Presumably, these variations may induce osteal obstruction, preventing mucus drainage and predisposing to chronic rhinosinusitis. However, this concept is still controversial and the presence of any anatomic variation does not necessarily establish an etiology for rhinosinusitis. Among three subtypes of concha bullosa, just the bulbous type seems to be strongly associated with symptoms. Size and obliteration of osteomeatal complex drainage pathways may be relevant as well. Variations and tomographic signs of sinusal disease occurring on the same side reinforce the likelihood of interference with the mucus drainage process. Computed tomography offers detailed study of anatomical variations and is an invaluable tool for managing clinical decisions and planning surgical strategies. Imaging assessment must be based on identification of variants, definition of their dimensions, as well as on their association with obstruction of drainage ostia and tomographic signs of sinus disease.

Keywords: Anatomical variations, Paranasal sinuses, Sinusitis, Computed tomography

Multidetector computed tomography has been progressively used for evaluation of coronary artery disease, so the knowledge about the anatomy of coronary arteries and veins is of fundamental importance.

Keywords: Coronary artery, Anatomy, Angiography, Multidetector computed tomography

Intracranial aneurysm rupture is a rare cause of morbidity and mortality in pregnancy, with a few endovascular treatment cases reported in the literature. In this study we report a case of a 37-year-old woman in the eighth gestational month presenting tomographic findings and clinical manifestations compatible with subarachnoid hemorrhage (Hunt Hess III) due to rupture of an ophthalmic segment aneurysm in the internal carotid artery.

Keywords: Cerebral aneurysm, Subarachnoid hemorrhage, Pregnancy, Endovascular embolization