F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) typically demonstrates prominent thymus uptake in normal children and young adults. A 12-year-old girl presenting with back pain and respiratory discomfort underwent an FDG PET/CT examination that demonstrated an anterior mediastinal mass with relatively low FDG uptake and an apparently separate FDG-positive nodular lesion superior to the larger mass. Surgical excision demonstrated a larger mature teratoma mass with a smaller thymic tissue nodule connected to the tumor with hourglass bridging.

We describe two neonatal patients where the final diagnosis differed in whom multidetector computed tomography (MDCT) angiography could clearly visualize the intrathoracic aberrant artery. The first case was a infant with a right intrathoracic tumor detected by fetal sonography. MDCT was performed 13 days after birth at a weight of 3492 g. An aberrant arteries arising from the Th10-high aorta toward the right lower lobe was detected. A right lower lobectomy was performed in the diagnosis of pulmonary sequestration. The latter was an infant born at 28 weeks of gestation. MDCT was performed to investigate an abnormal right upper lobar shadow 92 days after birth at a weight of 2906 g. An aberrant arteries arising from the Th5-high aorta toward the right upper lobe was detected. We determined the artery considered aberrant was an inflammatory dilated bronchial artery by conventional angiography. MDCT could visualize ultra-fine aberrant arteries in neonates. However, it cannot explore the artery peripherally or evaluate the area controlled by the artery. Conventional angiography should be performed in cases without a branch defect of the bronchus or pulmonary artery, and in those cases with an aberrant artery arising from Th5-Th6-high thoracic aorta, which cannot be distinguished from the bronchial artery.