OBJECTIVE: To evaluate the role of the equilibrium phase in abdominal computed tomography. MATERIALS AND METHODS: A retrospective, cross-sectional, observational study reviewed 219 consecutive contrast-enhanced abdominal computed tomography images acquired in a three-month period, for different clinical indications. For each study, two reports were issued - one based on the initial analysis of non-contrast-enhanced, arterial and portal phases only (first analysis), and a second reading of these phases added to the equilibrium phase (second analysis). At the end of both readings, differences between primary and secondary diagnoses were pointed out and recorded, in order to measure the impact of suppressing the equilibrium phase on the clinical outcome for each of the patients. The extension of the exact Fisher's test was utilized to evaluate the changes in the primary diagnosis (p < 0.05 as significant). RESULTS: Among the 219 cases reviewed, the absence of the equilibrium phase determined change in the primary diagnosis in only one case (0.46%; p > 0.999). As regards secondary diagnoses, changes after the second analysis were observed in five cases (2.3%). CONCLUSION: For clinical scenarios such as cancer staging, acute abdomen and investigation for abdominal collections, the equilibrium phase is dispensable and does not offer any significant diagnostic contribution.

Keywords: X-ray computed tomography; Ionizing radiation; Neoplasm staging; Acute abdomen.

OBJECTIVE: To evaluate the incidence of postprocedural complications in patients submitted to transrectal ultrasound-guided prostate biopsy at the Unit of Intervention, Department of Imaging Diagnosis of Escola Paulista de Medicina - Universidade Federal de São Paulo. MATERIALS AND METHODS: Telephone interviews were conducted with 132 patients who had undergone transrectal ultrasound-guided prostate biopsy in the period from April 2011 to June 2011, according to the institution's protocol. RESULTS: Post-biopsy complications were categorized into two groups - minor and major complications, according to their need for further clinical evaluation. Complications were reported by 59 patients (61.8%), most of them (86.4%) with mild and self-limited symptoms, classified as minor complications. Eight patients (8.2%) had major complications, one of which required in-hospital treatment. Urinary retention was the major and most common complication. CONCLUSION: The present study has demonstrated a low prevalence of major complications after transrectal prostate biopsy.

Keywords: Prostate; Biopsy; Morbidity; Ultrasonography; Complications.

OBJECTIVE: To assess the impact of oral ranitidine on the imaging quality in magnetic resonance cholangiopancreatography (MRCP). MATERIALS AND METHODS: Thirty-two patients underwent MRCP with 3D and 2D acquisitions, and three strategies for suppression of the gastrointestinal fluid signal: a) only at fasting; b) 12 hours after ingestion of 300 mg ranitidine; c) after oral administration of gadolinium solution. Three observers reviewed the images with a focus on the degree of visualization of the biliopancreatic tree. The interobserver agreement was evaluated with the kappa test. The difference between techniques and acquisition modalities were evaluated by means of average grading scores. RESULTS: The three strategies for suppression of the gastrointestinal fluid signal presented high reproducibility. The results with suppression of the gastrointestinal fluid signal with ranitidine where similar to those obtained with fasting, and both were worse than those obtained with gadolinium solution. The 3D acquisitions surpassed 2D only in terms of visibility of the cystic duct and gallbladder, and were inferior or equivalent in the other biliopancreatic ductal segments. CONCLUSION: The use of ranitidine does not seem justified in the evaluation of the biliopancreatic tree at MRCP, since 2D MRCP with fasting allows the visualization of ductal structures with high quality and reproducibility in the majority of cases.

Keywords: Ranitidine; Diagnostic use; Magnetic resonance cholangiopancreatography; Contrast media; Bile ducts; Pancreatic ducts.

OBJECTIVE: To evaluate the therapeutic response to thyroid arterial embolization for primary hyperthyroidism. MATERIALS AND METHODS: Five women whose pharmacological treatment with thionamides failed to control Graves' disease were submitted to embolization of three dominant thyroid arteries (following assessment with ultrasound Doppler and arteriography) and followed-up at the 1st, 8th and 16th weeks after the procedure, with ultrasound Doppler, calcium blood test, thyroid function test and clinical examination. Three of the patients completed 16-week follow-up. RESULTS: None of the patients achieved permanent remission after 8 weeks. Disease recurrence was observed at the 24th week, despite the decrease in thyroid volume (49.5 ± 15.2%) observed at the 16th week. Complications were not observed, but radioiodine therapy was required for three of the patients followed-up. CONCLUSION: Embolization of three dominant thyroid arteries with polyvinyl alcohol allowed reduction in goiter volume in the three patients who completed the protocol, but was not effective to control hyperthyroidism.

Keywords: Hyperthyroidism; Treatment; Embolization.

OBJECTIVE: To compare, by means of ultrasonography, pre- and postoperative anatomical changes arising from experimentally induced obstructive jaundice in porcine models. MATERIALS AND METHODS: Six 36-day-old Landrace pigs underwent laparoscopically induced complete biliary obstruction by common bile duct ligation. RESULTS: No difficulty was faced during the procedures and the surgical recovery was uneventful. After seven days, the animals showed jaundice, bilirubinuria and acholic stools. Comparative ultrasonography allowed visualization of hepatomegaly, cholecystomegaly and increased caliber of the common bile duct in all the animals, as well as changes resulting from cholestasis. The morphometric analysis revealed a significant increase in diameter of the gallbladders and left lateral liver lobes. CONCLUSION: Pigs represent appropriate experimental models for investigation of obstructive jaundice, and ultrasonography has shown to be sensitive, playing a relevant role in the diagnosis of extrahepatic biliary obstruction in such animals.

Keywords: Biometry; Obstructive jaundice; Extrahepatic cholestasis.

OBJECTIVE: To evaluate the feasibility of using radiochromic films as an alternative dosimeter to estimate the multiple scan average dose on the basis on kerma profiles. MATERIALS AND METHODS: The radiochromic films were distributed in cylinders positioned in the center and in four peripheral bores of a standard abdominal phantom utilized for computed tomography dosimetry. RESULTS: Values for multiple scan average dose values corresponded to 13.6 ± 0.7, 13.5 ± 0.7 and 18.7 ± 1.0 mGy for pitch of 0.75, 1.00 and 1.50, respectively. CONCLUSION: In spite of results showing lower values than the reference level for radiodiagnosis (25 mGy) established by the Brazilian regulations for abdominal studies, it is suggested that there is room to optimize procedures and review the reference level for radiodiagnosis in Brazil.

Keywords: Kerma profiles; Computed tomography; Radiochromic films; MSAD.

Most temporal bone fractures result from high-energy blunt head trauma, and are frequently related to other skull fractures or to polytrauma. Fractures and displacements of ossicular chain in the middle ear represent some of the main complications of temporal bone injury, and hence they will be more deeply approached in the present article. Other types of injuries include labyrinthine fractures, dural fistula, facial nerve paralysis and extension into the carotid canal. Computed tomography plays a fundamental role in the initial evaluation of polytrauma patients, as it can help to identify important structural injuries that may lead to severe complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, facial nerve paralysis, vascular injury and others.

Keywords: Temporal bone trauma; Ossicular injuries; Ossicular trauma.

The purpose of this paper is to encourage the correct use of vocabulary in the field of diagnostic imaging.

Keywords: Radiology; Grammar; Portuguese.

The authors illustrate the present pictorial essay about central nervous system lymphoma with magnetic resonance images obtained in their institution over the past 13 years. Some of the main radiological findings in primary and secondary presentations of this type of lymphoma are discussed. Central nervous system lymphoma is a relatively uncommon tumor, but magnetic resonance imaging findings may suggest the diagnosis.

Keywords: Lymphoma; Central nervous system; Magnetic resonance imaging.

Magnetic resonance imaging plays a relevant role in the assessment of patients with pain on the dorsal aspect of the distal forearm and wrist. Among the causes of pain, intersection syndrome is highlighted, corresponding to an inflammatory process affecting the tendons of the second compartment of the forearm extensor (extensor carpi radialis brevis and extensor carpi radialis longus), usually caused by direct trauma or repetitive activities requiring wrist flexion and extension. The present essay is aimed at illustrating the typical findings in intersection syndrome of the forearm and discuss the main differential diagnoses.

Keywords: Forearm; Intersection; Magnetic resonance imaging; Extensor compartment

Pulmonary pseudocysts are uncommon cavitary lesions that develop in the lung parenchyma as a consequence of blunt thoracic trauma, whose diagnosis is based on an association of clinical history and imaging findings. The present report describes the case of a pulmonary pseudocyst observed in the parenchyma contralateral to the trauma site in a 31year-old man presenting with hemoptysis after falling during a soccer match.

Keywords: Pulmonary pseudocyst; Post-traumatic pseudocyst; Post-traumatic pneumatoceles.