Thoracic asymmetries characterized by increased radiolucency of the lungs are important causes of morbidity in infants and children. Evaluation of affected patients frequently requires multiple imaging methods to diagnose the abnormality and to plan the surgical correction. The authors review and illustrate the characteristics of both common and rare thoracic asymmetries with emphasis on the radiological findings. The usefulness of different imaging methods in the diagnosis and treatment of these conditions is evaluated. The differential diagnosis as well the pitfalls and diagnostic difficulties are also discussed.

Keywords: Thoracic diseases, Congenital cystic adenomatoid malformation, Congenital lobar emphysema, Congenital diaphragmatic hernia

OBJECTIVE: To describe the different tomographic findings in hypodense hepatic lesions in children and its differential diagnosis. MATERIALS AND METHODS: Computed tomographic studies were obtained from 50 patients (age range: 0-16 years) with low-density liver lesions previously diagnosed by ultrasound. Images were made before and after administration of intravenous contrast medium. Image findings were analyzed and afterwards correlated with anatomopathological diagnosis. RESULTS: Forty-seven of 50 cases were confirmed, 30 by anatomopathological diagnosis. Most of then were benign lesions, hemangioma in 20%. Such lesions presented a homogeneous contrast absorption, mainly at the delayed phase, differing from malignant lesions. Metastasis was the most frequently found malignant lesion (18%). CONCLUSION: Computed tomographic study is of great value in complementing the diagnosis of hypodense hepatic lesions in children, and must follow ultrasound diagnosis as a routine procedure.

Keywords: Hypodense hepatic injuries, Computed tomography, Childhood

OBJECTIVE: To compare duplex ultrasound and computed tomography (CT) angiography in terms of their performance in detecting endoleaks, as well as in determining the diameter of the aneurysm sac, in the postoperative follow-up of endovascular abdominal aortic aneurysm repair. MATERIALS AND METHODS: This was a prospective study involving 30 patients who had undergone endovascular repair of infrarenal aortoiliac aneurysms. Duplex ultrasound and CT angiography were performed simultaneously by independent radiologists. Measurements of the aneurysm sac diameter were assessed, and the presence or absence of endoleaks was determined. RESULTS: The average diameter of the aneurysm sac, as determined by duplex ultrasound and CT angiography was 6.09 ± 1.95 and 6.27 ± 2.16 cm, respectively. Pearson's correlation coefficient showing a statistically significant correlation (R = 0.88; p < 0.01). Comparing the duplex ultrasound and CT angiography results regarding the detection of endoleaks, we found that the former had a negative predictive value of 92.59% and a specificity of 96.15%. CONCLUSION: Our results show that there is little variation between the two methods evaluated, and that the choice between the two would have no significant effect on clinical management. Duplex ultrasound could replace CT angiography in the postoperative follow-up of endovascular aneurysm repair of the infrarenal aorta, because it is a low-cost procedure without the potential clinical complications related to the use of iodinated contrast and exposure to radiation.

Keywords: Aneurysm; Aorta, abdominal; Endovascular procedures; Ultrasonography; Angiography/methods.