Chest Imaging

Paraganglioma, thoracic

tumour of the paraganglionic cells (see neurogenic neoplasm mediastinal) that may be benign or malignant. Paragangliomas include phaeochromocytomas, functional tumour and chemodectomas. Their localization in the mediastinum is rare. Most of the chemodectomas are located closed to the aorta (lateral to the brachiocephalic artery, anterolateral to the aortic arch, close to the ductus arteriosus, or above and to the right of the right pulmonary artery). Multicentric localizations are possible. Most of the intrathoracic phaeochromocytomas arise in the posterior mediastinum, or adjacent to the heart and pericardium. Radiologically paragangliomas are seen as rounded soft tissue masses that are extremely vascular. They enhance highly at CT after administration of intravenous contrast medium. Hypervascularization may be confirmed on arteriography. Functional phaeochromocytomas may be detected by increased activity on radionuclide 131 I MIBG (metaiodobenzylguanidine) scans.

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