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.

OBJECTIVE: To evaluate the importance of computed tomography and computed tomography angiography (CTA) in stroke protocols, as well as their impact on endovascular treatment and on the determination of the etiology. MATERIALS AND METHODS: Were evaluated 28 patients with acute/hyperacute stroke in the anterior circulation who underwent intracranial and cervical CTA between April 2018 and August 2019. The parameters evaluated were the degree of stenosis, plaque characteristics, type of infarct, treatment, etiology, and the Alberta Stroke Program Early CT Score (ASPECTS). RESULTS: Of the 28 patients evaluated, 16 (57.1%) had an ASPECTS of 10 (the maximum score, indicative of normality). Four patients (14.3%) underwent thrombolytic treatment, and seven (25.0%) underwent mechanical thrombectomy. The etiology was atherosclerosis in 32.1% of the patients, cerebral small-vessel disease in 7.1%, cardioembolic in 7.1%, and undetermined in 53.6%. Regarding plaque, 17.9% of the patients presented stenosis ≥ 50%, 21.4% presented stable plaques, and 42.9% presented vulnerable plaques. Patients with a lower ASPECTS were more likely to have relevant stenosis and were more likely to have a total infarct. CONCLUSION: In the evaluation of patients with acute/hyperacute strokes, CTA provides important information, identifying occlusion, as well as helping define the etiology and inform decisions regarding treatment.

Keywords: Brain ischemia; Stroke/etiology; Brain infarction; Computed tomography angiography; Cerebral arteries/diagnostic imaging.

OBJECTIVE: We sought to evaluate the added value of complementary functional imaging in the differential diagnosis of parapharyngeal space lesions, as well as the benefit of performing a structured evaluation of diagnostic cross-sectional examinations. MATERIALS AND METHODS: This was a retrospective study of 16 patients with parapharyngeal space lesions who were referred to our facility following a cross-sectional imaging study listing head and neck paraganglioma as a possible diagnosis. Each patient underwent somatostatin receptor scintigraphy with ¹¹¹In-pentetreotide (Octreoscan) prior to surgical resection of the lesion. In addition, the initial computed tomography (CT) or magnetic resonance imaging (MRI) scans were reviewed by two radiologists specializing in head and neck imaging, working independently, according to predefined diagnostic criteria. RESULTS: Increased somatostatin receptor expression was observed in 14 of the 16 lesions evaluated. Histopathology of the surgical specimens showed that 11 of those 14 lesions were paragangliomas. Upon review, none of the three lesions for which there was a false-positive scintigraphy result (one intravascular meningioma and two schwannomas) were found to meet enough of the conventional imaging criteria for a diagnosis of paraganglioma. CONCLUSION: Structured analysis of imaging data increases the accuracy of the diagnosis of indeterminate parapharyngeal space lesions. Because of its high sensitivity, functional evaluation by somatostatin receptor scintigraphy should be considered a useful complementary tool for the detection of head and neck paraganglioma, provided that its limited specificity is taken into account.

Keywords: Parapharyngeal space/diagnostic imaging; Receptors, somatostatin; Radionuclide imaging; Paraganglioma/diagnosis; Neurilemmoma/diagnosis.

OBJECTIVE: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). MATERIALS AND METHODS This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD).The sample comprised eight women and six men.The median age was 55 years (range, 11–75 years).The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S.National Institutes of Health.The images were analyzed by two chest radiologists, who reached decisions by consensus. RESULTS: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%).Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%).The pulmonary abnormalities were bilateral in 12 cases (85.7%).The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). CONCLUSION: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

Keywords: Neurofibromatoses; Cysts; Lung diseases; Tomography, X-ray computed.

OBJECTIVE: To evaluate the resistive indices (RIs) of the fetal umbilical and middle cerebral arteries, as well as to determine the cerebroplacental ratio (CPR), in fetuses of women with hypertension. MATERIALS AND METHODS: This was a comparative cross-sectional study involving 75 pregnant women with pregnancy-induced hypertension (PIH) and 75 apparently healthy pregnant women (control group), all of whom were submitted to Doppler ultrasound examination of the fetal middle cerebral and umbilical arteries between 20 and 40 weeks of gestation. The two groups were compared in terms of the RI of the middle cerebral and umbilical arteries, as well as the CPR. The level of statistical significance was set at p ≤ 0.05. RESULTS: The mean age was 32.4 ± 4.6 years in the PIH group and 32.6 ± 4.6 years in the control group (p = 0.633). The mean umbilical artery RI was significantly higher in the PIH group than in the control group (0.67 ± 0.14 vs. 0.61 ± 0.08; p = 0.012), whereas the mean middle cerebral artery RI was significantly higher in the control group (0.80 ± 0.05 vs. 0.76 ± 0.08; p = 0.001). Among the women in the PIH group, the mean CPR was significantly lower for those with proteinuria than for those without (1.07 ± 0.26 vs. 1.27 ± 0.22; p = 0.001). CONCLUSION: Maternal hypertension during pregnancy appears to be associated with increased fetal umbilical artery RI and reduced fetal middle cerebral artery RI, as well as with a low CPR. In pregnant women, the combination of PIH and proteinuria is also apparently associated with an increased risk of a low CPR.

Keywords: Hypertension; Proteinuria; Ultrasonography, Doppler; Vascular resistance; Placenta/physiology; Pregnancy.

In recent decades, high-resolution ultrasound (HRUS) has revolutionized the morphological and structural evaluation of peripheral nerves and muscles, revealing details of the internal structure of the neural fascicles and muscle architecture. Applications range from diagnostics to interventional procedures. The anatomy of the forearm region is complex, with several muscles and an extensive network of vessels and nerves. To guarantee the success of the evaluation by HRUS, knowledge of the normal anatomy of the region is essential. The aim of these two companion articles is to present the normal anatomy of the nerves and compartments of the forearm, as revealed by HRUS, as well as the relationships between the main vessels and nerves of the region. Part 1 aims to review the overall structure of nerves, muscles and tendons, as seen on HRUS, and that of the forearm compartments. We present a practical approach, with general guidelines and tips on how best to perform the study. Part 2 is a pictorial essay about compartment vascularization and cutaneous innervation. Knowledge of the normal anatomy of the forearm improves the technical quality of the examinations, contributing to better diagnoses, as well as improving the performance and safety of interventional procedures.

Keywords: Ultrasonography/methods; Forearm/anatomy & histology; Radial nerve/anatomy & histology; Median nerve/anatomy & histology; Ulnar nerve/anatomy & histology.

In recent decades, high-resolution ultrasound (HRUS) has revolutionized the morphological and structural evaluation of peripheral nerves and muscles, revealing details of the internal structure of the neural fascicles and muscle architecture. Applications range from diagnostics to interventional procedures. The anatomy of the forearm region is complex, with several muscles and an extensive network of vessels and nerves. To guarantee the success of the evaluation by HRUS, knowledge of the normal anatomy of the region is essential. The aim of these two companion articles is to present the normal anatomy of the nerves and compartments of the forearm, as revealed by HRUS, as well as the relationships between the main vessels and nerves of the region. Part 1 aims to review the overall structure of nerves, muscles and tendons, as seen on HRUS, and that of the forearm compartments. We present a practical approach, with general guidelines and tips on how best to perform the study. Part 2 is a pictorial essay about compartment vascularization and cutaneous innervation. The relationships between arteries, satellite veins and nerves, as well as the relationship between cutaneous nerves and superficial veins, are demonstrated. Knowledge of the normal anatomy of the forearm improves the technical quality of the examinations, contributing to better diagnoses, as well as improving the performance and safety of interventional procedures.

Keywords: Ultrasonography/methods; Radial artery/anatomy & histology; Ulnar artery/anatomy & histology; Skin/innervation; Forearm/anatomy & histology.

Diseases involving the spinal cord include a heterogeneous group of abnormalities, including those of inflammatory, infectious, neoplastic, vascular, metabolic, and traumatic origin. Making the clinical differentiation between different entities is often difficult, magnetic resonance imaging being the diagnostic method of choice. Although the neuroimaging findings are not pathognomonic, many are quite suggestive, and the radiologist can assist in the diagnosis and, consequently, in the therapeutic guidance. In this first part of our article, the objective is to review the magnetic resonance imaging findings of the main neoplastic, vascular, metabolic, and traumatic spinal cord injuries.

Keywords: Magnetic resonance imaging; Spinal cord injuries; Neoplasms; Metabolic diseases; Wounds and injuries/diagnostic imaging.

Diseases involving the spinal cord include a heterogeneous group of abnormalities, including those of inflammatory, infectious, neoplastic, vascular, metabolic, and traumatic origin. Making the clinical differentiation between different entities is often difficult, magnetic resonance imaging being the diagnostic method of choice. Although the neuroimaging findings are not pathognomonic, many are quite suggestive, and the radiologist can assist in the diagnosis and, consequently, in the therapeutic guidance. In this second part of our article, the objective is to review the magnetic resonance imaging findings of the main inflammatory and infectious spinal cord injuries.

Keywords: Magnetic resonance imaging; Spinal cord/pathology; Spinal cord diseases; Inflammation; Infection.