In the name of GOD
Mediastinum
Anatomy
Pathology
Masses and mass like lesions Inflammatory changes Hematoma
Mediastinal masses
Imaging strategy Localized to mediastinum Localize within the mediastinum
Localize to the mediastinum Unlike lung lesions, a mediastinal mass will not contain air bronchograms. The margins with the lung will be obtuse. Mediastinal lines (azygoesophageal recess, anterior and posterior junction lines) will be disrupted. There can be associated spinal, costal or sternal abnormalities.
LEFT: A lung mass abutts the mediastinal surface and creates acute angles with the lung. RIGHT: A mediastinal mass will sit under the surface of the mediastinum, creating obtuse angles with the lung.
The lesion on the left was a pancoast tumor. The lesion on the right was a thymoma, located within the anterior mediastinum.
Anterior Mediastinum Thymus Teratoma (germ cell) Thyroid Terrible Lymphoma
ThymomaThymoma : most common primary neoplasm of the anterosuperior mediastinum Invasive thymoma Thymic carcinoma ThymolipomaThymolipoma / thymoliposarcomathymoliposarcoma Thymic cyst Benign thymic hyperplasia Thymic carcinoid Thymus
Thymic cyst
Cystic thymoma
Thyroid Thyroid neoplasms Thyroid goiter Parathyroid mass
Retrosternal thyroid
Retrosternal thyroid mass
Cervicothoracic sign
Lymphoma Hodgkin Lymphoma Non-Hodgkin lymphoma
lymphoma
Lymphoma (Hilum Overlay Sign: hilar vessels are seen through a mediastinal mass)
lymphoma
Germ cell tumours Mediastinal teratoma Mature:75% of mediastinal germ cell tumours Immature Teratocarcinoma Mediastinal seminoma Mediastinal emberional cell carcinoma Mediastinal yolk sac tumour Mediastinal choriocarcinoma Mediastinal mixed cell type germ cell tumour
Germ cell tumor
A fat-containing teratoma
Mediastinal teratoma
Germ cell tumor
Bronchogenic cyst – A benign growth with respiratory origins. Lymphadenopathy mediastinal – An enlargement of the lymph nodes. Pericardial cyst – A benign growth that results from an "out- pouching" of the pericardium (the heart’s lining). Thyroid mass mediastinal – Usually a benign growth, such as a goiter. These types of tumors can occasionally be cancerous. Tracheal tumors – These include tracheal neoplasms and non- neuplastic masses, such as tracheobronchopathia osteochondroplastica (benign tumors). Vascular abnormalities including aortic aneurysm and aortic dissection. Middle mediastinum
Pericardial cyst
Aortic aneurysm
Bronchogenic cyst
Posterior mediastinum Neurogenic tumors Neuroblastic tumors Non-neurogenic tumours Hernias
Neurogenic tumor
Neurogenic tumors Schwannoma Neurofibroma Malignant peripheral nerve sheath tumor
Neuroblastic tumors Neuroblastoma ganglioneuroma
neuroblastoma
Others Chordoma Pheochromocytoma Praspinal abscess Descending aortic aneurysm Esophageal neoplasm Hiatal hernia Bochdalek hernia Lymphadenopathy Extramedullary hematopoiesis Duplication cysts Thoracic meningocele
Extramedullary hematopoiesis
Bochdalek hernia
Intranthoracic meningocele
discitis
Foregut duplication cysts occasionally contain milk of calcium
4-year-old child with stridor
Duplication cyst
Hernia hernia
Esophageal varicosis
Mediastinal widdening >8 cm in the aortic knob depression of the left main-stem bronchus deviation of the naso-gastric tube to the right apical pleural haemoatoma (cap) disruption of the calcium ring in the aortic knob (broken-halo) Aortic injury in blunt trauma
Mediastinal hematoma
Some tips in differential diagnosis of mediastinal masses
Thymolipoma Teratoma (Germ cell tumors) Esophageal lipoma Fat deposition Lipoma Lipoblastoma Liposarcoma Extramedullary hematopoiesis Fat containing masses
Hyperenhancing lymph nodes Thyroid tissue Paragangliomas Hemangiomas Vascular Etiologies Enhancing masses
hemangioma
thyroid mass
Melanoma Renal cell carcinoma Thyroid carcinoma Castlemann's disease Enhancing lymphomas can be seen in:
Castlemann's disease
Thymic Cyst Thymoma Teratoma Pericardial Cyst Foregut Duplication Meningocoele Neuroenteric Cyst Cystic Lymphadenopathy Lymphangioma Fluid containing masses
Thank you