High Resolution CT Findings of Pseudoalveolar Sarcoidosis

PURPOSE: To determine the specific high-resolution CT features of sarcoidosis in which the observed pattern is predominantly pseudoalveolar. MATERIALS AND METHODS: We retrospectively reviewed the HRCT findings in 15 cases in which chest radiography demonstrated pseudoalveolar consolidation. In all 15, sarcoidosis was pathologically proven. The distribution and characterization of the following CT features was meticulously scrutinized: distribution and characterization of pseudoalveolar lesions, air-bronchograms, micronodules, thickening of bronchovascular bundles and interlobular septa, lung distortion, ground-glass opacities and combined hilar and mediastinal lymphadenopathy. Follow-up CT scans were available in three cases after corticosteroid administration. RESULTS: Between one and 12 (mean, 5.6) pseudoalveolar lesions appeared as dense homogeneous or inhomogeneous opacities 1-4.5 cm in diameter and with an irregular margin located either at the lung periphery adjacent to the pleural surface or along the bronchovascular bundles, with mainly bilateral distribution (n=14, 93%). An air-bronchogram was observed in ten cases. Micronodules were observed at the periphery of the lesion or surrounding lung, which along with a thickened bronchovascular bundle was a consistent feature in all cases. Additional CT features included hilar and mediastinal lymphadenopathy (n=14, 93%), thickened interlobular septa (n=12, 80%), and ground-glass opacity (n=10, 67%). Lung distortion was noted in only one case (7%). After steroid administration pseudoalveolar lesions decreased in number and size in all three cases in which follow-up CT was available. CONCLUSION: The consistent HRCT features of pseudoalveolar sarcoidosis are bilateral multifocal dense homogenous or inhomogenous opacity and an irregular margin located either at the lung periphery adjacent to the pleural surface or along the bronchovascular bundles. Micronodules are present at the periphery of the lesion or surrounding lung. The features are reversible at steroid administration.

CT Findings of Focal Organizing Pneumonia

PURPOSE: Focal organizing pneumonia (FOP) is a benign condition which is often difficult to differentiate from bronchogenic carcinoma, and many patients with FOP undergo invasive procedures. We tried to determine which CT features might help provide a confident diagnosis of FOP. MATERIALS AND METHODS: We retrospectively reviewed the medical records, chest radiographs and CT scans of 13 patients with histopathologically proven FOP. Initial chest radiographs in all 13 suggested bronchogenic carcinoma. The CT scans were reviewed by three radiologists, and final decisions were reached by consensus. They were analyzed in terms of the size, shape, contour and localization of the lesion, internal characteristics of the nodule, changes in surrounding structures, and changes in any of these findings, as revealed by follow-up chest CT scanning. RESULTS: FOP lesions were oval or triangular in shape and between 1.8 and 6.5 cm in their largest diameter. All had irregular margins and all but one were peripherally located. Eight (61.5%) were in contact with the pleura and five (38.5%) were located along the peripheral bronchovascular bundle, with pleural indentation; in eight (61.5%), post-contrast CT scanning revealed inhomogeneous enhancement, and four (30.8%) had pleural tags. In five (38.5%), there was coarse spiculation; for six (46.2%), air bronchograms were available, and in four (30.8%), satellite nodules were present. Spotty calcification and lymph node enlargement were each evident in one case only. Follow-up CT scanning, available in four cases, showed that the mass decreased in size in three and disappeared completely in one. CONCLUSION: Although there were no consistent CT features for differentiating focal organizing pneumonia from lung cancer, the possibility of the former should be considered when a peripherally-located oval or triangular-shaped mass is in broad contact with the pleura or is located along the bronchovascular bundle, and satellite nodules are also present.

Intracranial Hemorrhage in Late Hemorrhagic Disease of the Newborn: Brain Computed Tomographic Findings / 대한소아신경학회지

PURPOSE: This study is to evaluate the Brain CT manifestations of late hemorrhagic disease of the newborn. METHODS: We evaluated 13 cases with late hemorrhagic disease of the newborn, for whom brain CT scans were performed. Clinical indications for brain CT scan were mental changes(n=5), vomiting(n=2), irritability(n=2), seizure(n=3), and lethargy(n=1). We analyzed the result of the brain CT findings with attention to anatomic locations of hemorrhage and characteristics of hemorrhagic manifestations. RESULTS: Only one patient in 13 patients was normal on brain CT scan, and 12 patients showed hemorrhagic lesions. Among 12 patients, 5 cases had single hemorrhagic lesion(3 subdural hemorrhages and 2 intracerebral hemorrhages, and 7 cases had multiple lesions, in which subdural hemorrhage and subarachnoid hemorrhage were common respectively. The other common brain CT findings except hemorrhagic lesion were the mass effects with ventricle compression(n=11), midline shifting(n=6), ventricular dilatation(n=7), and fluid-fluid levels in hemorrhagic lesion(n=9). CONCLUSION: The common intracranial hemorrhages of late hemorrhagic disease of the newborn were subdural and subarachnoid hemorrhages. The associated CT findings were mass effect and fluid-fluid levels. Intracranial hemorrhage in late hemorrhagic disease of newborn could massively occurr. Thus brain CT scan should be done if any symptom for neurologic abnormality was present.