Lucas Rios Torres

Abdominal tuberculosis: a radiological review with emphasis on computed tomography and magnetic resonance imaging findings.

Tuberculosis is a disease whose incidence has increased principally as a consequence of HIV infection and use of immunosuppressive drugs. The abdomen is the most common site of extrapulmonary tuberculosis. It may be confused with several different conditions such as inflammatory bowel disease, cancer and other infectious diseases. Delay in the diagnosis may result in significantly increased morbidity, and therefore an early recognition of the condition is essential for proper treatment. In the present essay, cases with confirmed diagnosis of abdominal tuberculosis were assessed by means of computed tomography and magnetic resonance imaging, demonstrating the involvement of different organs and systems, and presentations which frequently lead radiologists to a diagnostic dilemma. A brief literature review was focused on imaging findings and their respective prevalence.

Tumores hepáticos incomuns: ensaio iconográfico - Parte 1

Most malignant liver tumors are represented by hepatocellular carcinoma and cholangiocarcinoma; however a variety of other uncommon hepatic lesions might also be found. Common lesions such as hemangioma, focal nodular hyperplasia and metastases are well known and have already been extensively documented in the literature. The diagnosis of typical hepatic lesions may be done with some reliability by means of several imaging methods; on the other hand, uncommon lesions normally represent a diagnostic challenge for the radiologist. In this first part of the study, the authors will approach five uncommon liver tumors - angiosarcoma, angiomyolipoma, cystadenoma/biliary carcinoma, epithelioid hemangioendothelioma, and fibrolamellar hepatocellular carcinoma -, describing their main characteristics and image findings with focus on computed tomography and magnetic resonance imaging.

The role of gadoxetic acid as a paramagnetic contrast medium in the characterization and detection of focal liver lesions: a review

Magnetic resonance imaging (MRI) has several advantages in the evaluation of cancer patients with thoracic lesions, including involvement of the chest wall, pleura, lungs, mediastinum, esophagus and heart. It is a quite useful tool in the diagnosis, staging, surgical planning, treatment response evaluation and follow-up of these patients. In the present review, the authors contextualize the relevance of MRI in the evaluation of thoracic lesions in cancer patients. Considering that MRI is a widely available method with high contrast and spatial resolution and without the risks associated with the use of ionizing radiation, its use combined with new techniques such as cine-MRI and functional methods such as perfusion- and diffusion-weighted imaging may be useful as an alternative tool with performance comparable or complementary to conventional radiological methods such as radiography, computed tomography and PET/CT imaging in the evaluation of patients with thoracic neoplasias.

Prevalence of simple liver cysts and hemangiomas in cirrhotic and non-cirrhotic patients submitted to magnetic resonance imaging

Objective To determine the prevalence of liver cysts and hemangiomas in the general population and in cirrhotic patients. Materials and Methods Retrospective, observational, and cross-sectional study selecting consecutive magnetic resonance imaging studies performed in the period from February to July 2011. A total of 303 patients (187 women and 116 men) with mean age of 53.3 years were included in the present study. Patients with previously known liver lesions were excluded. The images were consensually analyzed by two observers in the search for simple liver cysts and typical liver hemangiomas, according to universally accepted imaging criteria. Lesions prevalence, diameters and location were determined in both cirrhotic and non-cirrhotic individuals. Results The authors observed prevalence of 8.6% for hemangiomas and 14.5% for simple cysts. No statistically significant difference was observed in relation to prevalence of hemangiomas and cysts among cirrhotic and non-cirrhotic patients (p = 0.954; p = 0.472). Conclusion In the present study, the prevalence of cysts and hemangiomas was higher than the prevalence reported by autopsy series. No influence of cirrhosis was observed on the prevalence and appearance of such incidental lesions.

Hemangioendotelioma hepático multifocal e metastático: relato de caso e revisão da literatura

Epithelioid hemangioendothelioma is a rare neoplasm of vascular origin whose involvement of organs such as lung, spleen, bone, breast and liver has already been reported. The clinical signs and the prognosis of this tumor are quite variable. From the present case report, the authors have sought to contribute with literature data, by reviewing clinical and radiological features which may be useful to include such a condition in the differential diagnosis of liver lesions.Epithelioid hemangioendothelioma is a rare neoplasm of vascular origin whose involvement of organs such as lung, spleen, bone, breast and liver has already been reported. The clinical signs and the prognosis of this tumor are quite variable. From the present case report, the authors have sought to contribute with literature data, by reviewing clinical and radiological features which may be useful to include such a condition in the differential diagnosis of liver lesions.

Readjustment of abdominal computed tomography protocols in a university hospital: impact on radiation dose.

Objective To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters. Materials and Methods Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A – 551 studies) and three months after (group B – 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDIvol per phase, mean DLP per phase, and mean DLP per scan. Results A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDIvol per phase, DLP per phase and DLP per scan (p < 0.001). Conclusion The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans.

Alcoolização percutânea de cistos renais: revisão da literatura e apresentação de resultados

OBJECTIVE: To demonstrate the effectiveness and practical outcomes of percutaneous ethanol sclerotherapy in patients with symptomatic simple renal cysts. MATERIALS AND METHODS: The authors reviewed the outcomes of ten patients (eight men and two women) in the age range between 28 and 72 years (mean, 55 years) submitted to at least two procedures of percutaneous sclerotherapy for symptomatic simple renal cysts. Main presentation was refractory flank pain in all patients, seven of them with some degree of hydronephrosis because of the parapyelic localization of the cyst. The aspirated volume ranged from 20 to 1300 ml (mean, 200 ml). The mean follow-up period following the procedure was of seven months. Two patients had ultrasoud-guided sclerotherapy, and eight, computed tomography-guided sclerotherapy. The hospital stay period ranged between 24 and 72 hours. Complete success corresponded to total cyst regression, and partial success corresponded to recurrence of less than half the original cyst volume. RESULTS: Complete cyst ablation was achieved in seven patients and partial resolution in three. No complication was observed and the therapy was well tolerated by all of the patients. CONCLUSION: Percutaneous ethanol sclerotherapy of symptomatic simple renal cysts is a safe, effective and minimally invasive procedure, with results similar to the ones reported by other studies.

Tumor do estroma gastrintestinal: achados clínicos, radiológicos e anatomopatológicos

OBJECTIVE: To investigate and describe clinical, radiologic and pathologic findings of gastrointestinal stromal tumors. MATERIALS AND METHODS: In the period between December 2000 and March 2006, 16 patients were submitted to surgery for gastrointestinal stromal tumors in our institution. The following variables were taken into consideration: sex and age, signs and symptoms at presentation, tumor site and size, radiological and pathological features, and presence of metastasis. RESULTS: The study population was constituted by nine men and seven women. The primary tumor sites of origin were: stomach (n = 5), rectum (n = 4), small bowel (n = 3), mesentery (n = 3), and colon (n = 1). Mean primary tumor size was 9 cm. Computed tomography was the main radiological method utilized. Circumscribed, lobulated and heterogeneously contrast-enhanced mass was the main image finding. Metastasis was found in nine patients (56% of cases) at presentation or tumor recurrence was observed during the follow-up period (mean = 32 months). CONCLUSION: Gastrointestinal stromal tumor occurs in middle-age adults and the elderly, and must be taken into consideration as differential diagnosis for abdominal masses. Early diagnosis, adequate therapy, and rigorous follow-up are essential, considering the high probability of malignancy of these neoplasms as demonstrated by the present study.

Actinomicose laríngea: relato de caso

We report a case of a patient with actinomycosis of the larynx mimicking a neoplasm. A literature review, clinical features, pathology and imaging findings is also presented. This paper reports a rare disease occurring in an atypical location, simulating larynx neoplasm. To our knowledge, there is no report of this disease and locations evaluated with computed tomography.

Is liver perfusion CT reproducible? A study on intra- and interobserver agreement of normal hepatic haemodynamic parameters obtained with two different software packages

OBJECTIVE To evaluate the agreement between the measurements of perfusion CT parameters in normal livers by using two different software packages. METHODS This retrospective study was based on 78 liver perfusion CT examinations acquired for detecting suspected liver metastasis. Patients with any morphological or functional hepatic abnormalities were excluded. The final analysis included 37 patients (59.7 ± 14.9 y). Two readers (1 and 2) independently measured perfusion parameters using different software packages from two major manufacturers (A and B). Arterial perfusion (AP) and portal perfusion (PP) were determined using the dual-input vascular one-compartmental model. Inter-reader agreement for each package and intrareader agreement between both packages were assessed with intraclass correlation coefficients (ICC) and Bland-Altman statistics. RESULTS Inter-reader agreement was substantial for AP using software A (ICC = 0.82) and B (ICC = 0.85-0.86), fair for PP using software A (ICC = 0.44) and fair to moderate for PP using software B (ICC = 0.56-0.77). Intrareader agreement between software A and B ranged from slight to moderate (ICC = 0.32-0.62) for readers 1 and 2 considering the AP parameters, and from fair to moderate (ICC = 0.40-0.69) for readers 1 and 2 considering the PP parameters. CONCLUSION At best there was only moderate agreement between both software packages, resulting in some uncertainty and suboptimal reproducibility. Advances in knowledge: Software-dependent factors may contribute to variance in perfusion measurements, demanding further technical improvements. AP measurements seem to be the most reproducible parameter to be adopted when evaluating liver perfusion CT.