OBJECTIVE: To evaluate the interobserver agreement on non-contrast computed tomography interpretation by a group of experienced abdominal radiologists, for the study of urolithiasis in patients presenting acute flank pain. MATERIALS AND METHODS: Prospective study of 52 patients submitted to non-contrast enhanced helical computed tomography. The images were subsequently analyzed by three independent observers, with the interobserver agreement assessed by means of the kappa (kappa) statistical method. The following parameters were analyzed: a) presence, localization and measurement of ureteral calculi; b) intrarenal calyceal system dilatation; c) perirenal fat heterogeneity; d) ureteral dilatation; e) ureteral wall edema (halo sign). RESULTS: Ureteral calculi were found in 40 of 52 patients (77%). The interobserver agreement was almost perfect as regards identification of ureteral calculi (kappa = 0.89) and ureteral dilatation (kappa = 0.87), substantial for calyceal system dilatation (kappa = 0.77), and moderate for perirenal fat heterogeneity (kappa = 0.55) and ureteral wall edema (kappa = 0.56). CONCLUSION: Non-contrast-enhanced abdominal computed tomography presents high reproducibility in the evaluation of urolithiasis and secondary signs of the calyceal system obstruction.

Keywords: Lithiasis, Ureteral calculi, Flank pain, Computed tomography

OBJECTIVE: To define, by means of computed tomography, the level of ureteral implantation into de bladder. MATERIALS AND METHODS: We have measured the distances from the ureteral meatus to the acetabulum, and to the superior margin of the pubic symphysis, as well as the bladder volume, using contrast enhanced computed tomography of the pelvis in 46 patients (31 male and 15 female) in the age range between 18 and 45 years, with at least one of the ureteres filled with excreted contrast material. The Student t test has been applied to determine eventual statistically significant differences between groups. RESULTS: The level of ureteral implantation into the bladder was, on average, 10.6 ± 8.1 mm below the acetabular roof, and 29.7 ± 9.5 mm above the superior margin of the pubic symphysis. In patients with bladder repletion volume of < 200 ml and > 200 ml, the level of ureteral implantation into the bladder was, respectively, on average, 11.6 ± 7.3 mm and 10.2 ± 8.4 mm below the acetabular roof (p = 0.61), and 28.3 ± 7.3 mm and 30.3 ± 10.2 mm above the superior margin of the pubic symphysis (p = 0.52), and in male and female men patients, respectively, on average, 11.8 ± 8.0 mm and 8.3 ± 8.0 mm below the acetabular roof (p = 0.17), and 27.7 ± 9.2 mm and 33.9 ± 8.8 mm above the superior margin of the pubic symphysis (p = 0.34). CONCLUSION: Calcifications located < 3 cm below the acetabular roof and < 1.5 cm above the superior margin of the pubic symphysis probably do not represent ureteral calculi. Vesical repletion or sex have no significant influence on the ureteral meatus position.

Keywords: Calculus, Ureter, Ureteral obstruction, Lithiasis, X-ray computed tomography

We present a case of a 27-year-old male patient submitted to computed tomography and magnetic resonance imaging for the evaluation of a renal tumor. The radiological features of the mass suggested the diagnosis of a malignant renal tumor of parenchymatous origin. However, the histological findings proved to be a benign solitary fibrous tumor within the pelvis and caliceal portion of the right kidney.

Keywords: Neoplasia, Fibrous tumor, Kidney, Mesothelioma, Computed tomography, Magnetic resonance imaging

The most important diagnostic sign of ureterolithiasis is the direct visualization of the stone within the ureter. However, in some patients with ureterolithiasis stone visualization may be impaired due to stone small size or low attenuation, respiratory artifacts between data acquisitions, low amount of retroperitoneal fat or recent elimination of the stone. In this context, we describe many secondary computed tomography signs of ureteral obstruction that may useful in the diagnosis of inconclusive cases, and also quantify the degree of urinary obstruction.

Keywords: Computed tomography, Acute flank pain, Ureteral stone

The melanotic neuroectodermal tumor of infancy, also known as progonoma, is a rare benign disease of neural crest origin that occurs within the first year of life and affects mainly the maxilla. The authors report a case of a 10-month-old child presenting with this uncommon tumor in the maxilla, emphasizing the diagnostic findings on computed tomography, and present a literature review.

Keywords: Neoplasia, Neural crest, Maxilla, Infancy, Computed tomography

The literature reports only rare cases of urinary ascites, usually secondary to rupture of the bladder and not to renal calyx rupture. The present report describes an uncommon case of posterior urethral valve in a newborn with ascites caused by the rupture of a renal calyx that, to our knowledge, was diagnosed for the first time by ultrasonography.

Keywords: Newborn; Urinary ascites; Renal calyx rupture; Posterior urethral valve; Ultrasonography.

OBJECTIVE: To present a data analysis toolkit that may be utilized with the purpose of radiation protection of hospital inpatients and workers in areas where mobile apparatuses are used. MATERIALS AND METHODS: An Excel^® ActiveSheet was utilized to develop a computational toolkit with exposure measurements to generate a database of shape factors and to calculate the air kerma around hospital beds. The initial database included data collected with three mobile apparatuses. A non-anthropomorphic phantom was utilized and exposure measurements were performed on a (4.2 × 4.2) m² mesh-grid at 0.3 m steps. RESULTS: The toolkit calculates the air kerma (associated with patients' radiation exposure and with ambient equivalent dose) under secondary radiation. For distances lower than 60.0 cm, values above the maximum ambient equivalent dose threshold defined for radiation free areas (0.5 mSv/year) were verified. Data collected at 2.1 m have always presented values lower than 12% of that threshold. CONCLUSION: The toolkit can aid in the radiological protection of patients and workers, provided it is combined with appropriate data collection, since it allows the determination of radiation free areas around beds in rooms where mobile X-ray apparatuses are utilized.

Keywords: Radiology; Radiological protection; Software toolkit.

OBJECTIVE: To investigate the learning about management of the technology (efficient use, acquisition and maintenance of imaging diagnosis equipment) in the radiology residency program of Escola Paulista de Medicina - Universidade Federal de São Paulo, with a view to improving the education of radiologists. MATERIALS AND METHODS: Exploratory research where residents, faculty staff and tutors of the program were quantitative and qualitatively approached with Likert scale questionnaires (46), and deepening with recorded interviews (18) and categorization based upon meaning units (thematic analysis). RESULTS: Among the participants, 66% agreed that they had the opportunity of learning about the use of radiological equipment; for 61% the program should include knowledge on the importance of acquiring equipment; and 72% emphasized the lack of learning about equipment management and maintenance. CONCLUSION: As the major moment in the education of specialists, the medical residency program provides residents with a favorable environment to the learning of the skills required to the future of their professional practice, but with limited emphasis on the management of the technology: efficient use, acquisition and mainly maintenance of equipment, still poorly explored. Both the investigated program and the medical residency in radiology should incorporate, whenever possible, the commitment with the training in supplementary skills related to equipment management, developing the competence of the future radiologists.

Keywords: Medical education; Medical residency; Health management; Radiologic technology; Radiology; Imaging diagnosis.

In the investigation of tumors with conventional magnetic resonance imaging, both quantitative characteristics, such as size, edema, necrosis, and presence of metastases, and qualitative characteristics, such as contrast enhancement degree, are taken into consideration. However, changes in cell metabolism and tissue physiology which precede morphological changes cannot be detected by the conventional technique. The development of new magnetic resonance imaging techniques has enabled the functional assessment of the structures in order to obtain information on the different physiological processes of the tumor microenvironment, such as oxygenation levels, cellularity and vascularity. The detailed morphological study in association with the new functional imaging techniques allows for an appropriate approach to cancer patients, including the phases of diagnosis, staging, response evaluation and follow-up, with a positive impact on their quality of life and survival rate.

Keywords: Cancer imaging; Magnetic resonance imaging; Oncology; Neoplasia; Functional imaging; Diffusion.

OBJECTIVE: The present study was aimed at evaluating the contribution of transrectal prostate ultrasound in the screening for prostate neoplasias and in the guidance of prostate biopsies. MATERIALS AND METHODS: Prospective study developed over a one-year period. All the patients with indication for prostate biopsy were evaluated. Regardless of PSA values, the patients underwent ultrasound in order to identify suspicious nodules (confirmed by two observers). Sextant biopsy was subsequently performed. In cases of finding suspicious nodules, an additional puncture directed to such nodules was done. RESULTS: In a total of 155 cases the prevalence of malignancy was of 53%. Suspicious nodules were detected in 34 patients, and 25 where malignant (positive predictive value of 74%). The specificity and sensitivity for suspicious nodules were 88% and 31% respectively. Comparatively with the randomly obtained sextant specimens, the rate of findings of neoplasia was higher in the specimens obtained with puncture directed to the nodule (p = 0.032). No statistically significant difference was observed in the Gleason score for both types of specimens (p = 0.172). CONCLUSION: The high positive predictive value and the high rate of findings of neoplasia in specimens of suspicious nodules should be taken into consideration in the future. The authors suggest a biopsy technique similar to the one described in the present study (sextant biopsy plus puncture directed to the suspicious nodule).

Keywords: Prostatic neoplasia; Ultrasonography; Imaging-guided biopsy; Diagnostic techniques and procedures; Screening.

OBJECTIVE: To describe the radiological findings of pulmonary tuberculosis in indigenous patients from the city of Dourados, MS, Brazil, according to age and sex. MATERIALS AND METHODS: Chest radiographic images of 81 patients with pulmonary tuberculosis, acquired in the period from 2007 to 2010, were retrospectively analyzed by two radiologists in consensus for the presence or absence of changes. The findings in abnormal radiographs were classified according to the changes observed and they were correlated to age and sex. The data were submitted to statistical analysis. RESULTS: The individuals' ages ranged from 1 to 97 years (mean: 36 years). Heterogeneous consolidations, nodules, pleural involvement and cavities were the most frequent imaging findings. Most patients (55/81 or 67.9%) were male, and upper lung and right lung were the most affected regions. Fibrosis, heterogeneous consolidations and involvement of the left lung apex were significantly more frequent in males (p < 0.05). Presence of a single type of finding at radiography was most frequent in children (p < 0.05). CONCLUSION: Based on the hypothesis that indigenous patients represent a population without genetically determined resistance to tuberculosis, the present study may enhance the knowledge about how the pulmonary form of this disease manifests in susceptible individuals.

Keywords: Radiology; Tuberculosis; Chest; Radiological findings; Indigenous population.

OBJECTIVE: To determine the rates of diagnostic underestimation at stereotactic percutaneous core needle biopsies (CNB) and vacuum-assisted biopsies (VABB) of nonpalpable breast lesions, with histopathological results of atypical ductal hyperplasia (ADH) or ductal carcinoma in situ (DCIS) subsequently submitted to surgical excision. As a secondary objective, the frequency of ADH and DCIS was determined for the cases submitted to biopsy. MATERIALS AND METHODS: Retrospective review of 40 cases with diagnosis of ADH or DCIS on the basis of biopsies performed between February 2011 and July 2013, subsequently submitted to surgery, whose histopathological reports were available in the internal information system. Biopsy results were compared with those observed at surgery and the underestimation rate was calculated by means of specific mathematical equations. RESULTS: The underestimation rate at CNB was 50% for ADH and 28.57% for DCIS, and at VABB it was 25% for ADH and 14.28% for DCIS. ADH represented 10.25% of all cases undergoing biopsy, whereas DCIS accounted for 23.91%. CONCLUSION: The diagnostic underestimation rate at CNB is two times the rate at VABB. Certainty that the target has been achieved is not the sole determining factor for a reliable diagnosis. Removal of more than 50% of the target lesion should further reduce the risk of underestimation.

Keywords: Breast neoplasia; Core needle biopsy; Vacuum-assisted biopsy; Diagnostic techniques and procedures; Noninvasive intraductal carcinoma.

Objective: To analyze the results obtained with a modified antegrade double J catheter insertion (JJ stenting) technique in patients with urinary tract obstruction due to malignancy. Materials and Methods: This was a retrospective analysis of data collected from patients undergoing antegrade JJ stenting for malignant ureteral obstruction in the interventional radiology department of our institution between March 1, 2017 and May 31, 2019. Results: Antegrade JJ stenting was performed in 32 patients (20 women and 12 men). The mean age was 66.2 years among the females and 61.5 years among the males. A total of 53 antegrade JJ stenting procedures were performed. The procedure was successful in 50 cases and failed in 3 (due to migration of the double J catheter in 2 and due to technical failure in 1). Complications occurred in 3 patients (low back pain, in 1, subcapsular hematoma, in 1, and pyelonephritis, in 1). The procedure time ranged from 14 min to 55 min. Conclusion: In patients with ureteral obstruction due to malignancy, antegrade JJ stenting is safe and effective. The technique selected in our study is easily reproduced and can be performed by a trained professional.

Keywords: Urinary catheterization/instrumentation; Stents; Ureteral obstruction; Radiology, interventional; Urologic neoplasms.

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.

OBJECTIVE: To present our clinical experience with percutaneous antegrade ureteral stenting. MATERIALS AND METHODS: This was a single-center retrospective study in which we reviewed the electronic medical records of patients who underwent percutaneous image-guided antegrade ureteral stenting between January 2016 and August 2020. We evaluated 90 patients (48 men). The mean age was 61.4 ± 15 years (range, 30–94 years). Patients were divided into two main groups: those with malignant neoplasms; and those with non-neoplastic disease. Technical and clinical success of the procedure were defined, respectively, as maintenance of the patency of the urinary tract, with a reduction in the degree of hydronephrosis, and as a reduction in the level of nitrogenous waste. Postprocedural complications were categorized as major or minor according to the CIRSE classification. RESULTS: The study sample comprised 150 antegrade stenting procedures performed in 90 patients, most of whom had previously undergone retrograde stenting that was unsuccessful. The stenting was bilateral in 60 patients and unilateral in 30. Technical success was achieved in 143 (95.3%) of the procedures, whereas seven procedures (4.6%) were unsuccessful. Failed procedures were characterized by inability to place a stent or migration of a stent after its placement. Complications occurred in 12 (8.0%) of the procedures. Of those 12 complications, two were classified as major (bleeding) and 10 were classified as minor (lumbar pain or infection). The most common techniques used were the over-the-wire technique and the modified technique (in 58.0% and 42.0% of the cases, respectively). In seven cases (4.7%), a nephrostomy tube was inserted. CONCLUSION: Percutaneous antegrade ureteral stenting is a safe, effective method for the management of ureteral injuries and obstructions, due to malignant or benign causes, when the retrograde approach has failed.

Keywords: Urinary catheterization/instrumentation; Stents; Ureteral obstruction; Radiology, interventional; Urologic neoplasms.