Download to read offline
More Related Content
Similar to mediastiniumnew-140731113229-phpapp02.pptx
![PERI-PROSTHETIC FRACTURE NAIL-PLATE CONSTRUCT [NPC].pptx](https://cdn.slidesharecdn.com/ss_thumbnails/drarunkumardrmohamedashrafperiprostheticfrasturenail-plateconstructnpc-260209164459-7e9d15a1-thumbnail.jpg?width=640&height=640&fit=bounds)
![CTEV [ clubfoot] DR ARUN LAL ,DR MOHAMED ASHRAF travancore medical college k...](https://cdn.slidesharecdn.com/ss_thumbnails/ctevclubfootdrarunlaldrmohamedashraftravancoremedicalcollegekollamkeralaindia-260208063247-18fc466c-thumbnail.jpg?width=640&height=640&fit=bounds)
mediastiniumnew-140731113229-phpapp02.pptx
- 1. mediastinum Dr. Deepak G Assistantprofessor Dept of Gen surgery
- 2. Introduction ●The mediastinum isthe region in the chest between the pleural cavities that contain the heart and other thoracic viscera except the lungs ●Boundaries ● Anterior - sternum ● Posterior - vertebral column and paravertebral fascia ● Superior -thoracic inlet ● Inferior - diaphragm ● Lateral - parietal pleura
- 3. Sternal Angle Thoracic inlet Thoracicoulet Boundaries of mediastinum sternum Thoracic vertebra
- 4.
- 5.
- 6. Superior Mediastinum Posterior Mediastinum Anterior Mediastinum Middle Mediastinum Sternal Angle T4 T5 divided into superiormediastinum and inferior mediastinum by an imaginary line passing through sternal angle anteriorly lower border of 4th thoracic vertebra posteriorly Mediastinum divisions
- 7. Inferior mediastinum: is subdividedinto ❑ Anterior mediastinum ❑ Middle mediastinum ❑ Posterior mediastinum
- 8. Superior Mediastinum Boundaries ❑ Ant:Manubrium sterni ❑ Post: T-1 to T-4 ❑ Sides: Mediastinal pleura ❑ Sup: Plane of thoracic inlet at T1 ❑ Inf: Imaginary line joining sternal angle and lower border T-4 9
- 9. Superior Mediastinum ● Itcontains: ❑ Trachea ❑ Esophagus ❑ Blood vessels (large veins & arteries) (listed later) ❑ Nerves (listed later) ❑ Thoracic duct ❑ Thymus ❑ Lymph nodes: (listed later)
- 10. Superior mediastinum contents BloodVessels Veins: ⮚SVC ⮚Lt & Rt brachiocephalic veins, Arteries: ⮚Arch of Aorta ⮚Brachiocepalic artery ⮚Lt Common carotid ⮚Lt subclavian artery
- 11. Superior Mediastinum Nerves 1. Vagusnerve 2. Left Recurrent Laryngeal nerve. 3. Phrenic nerve.
- 12. Superior Mediastinum Lymph nodes: ❑Highest mediastinal ❑ Paratracheal ❑ Prevascular ❑ retrotracheal
- 13. Anterior Mediastinum ●Lies ant.to pericardium ●Boundaries: ❑Anterior: body of sternum ❑Posterior: pericardium ❑superior: imaginary line separating sup. & inf.mediastinum ❑Infreior: diaphragm ❑Lateral: mediastinal pleura
- 14. Anterior mediastinum: contains: a.Thymus gland b. Lymph Nodes c. Fat.
- 15. Thymus ● Located inanterior mediastinum. ● Develops from endoderm of 3rd pharyngeal pouch ● Present in childhood, involutes in adults ● Blood supply ⮚Arterial :i nt. Mammary arteries ⮚Venous: internal thoracic veins ⮚Lymphatic drainage: lower cervical, int. Mammary and hilar nodes
- 16. Middle Mediastinum ●Boundaries: ❑Anterior: posteriorsurface of sternum ❑Posterior: oesophagus, desc. thoracic aorta, azygous vein ❑Superior: plane seperating sup.& inf mediastinum ❑Inferior: diaphragm ❑Lateral: mediastinal pleura
- 17. Middle Mediastinum Contents: Heart enclosedin pericardium Arteries: Ascending Aorta, Pulmonary trunk with its Lt & Rt branches Veins: SVC,Pulmonary veins Nerves: Phrenic, vagus nerve Bifurcation of Trachea with two principal bronchi Tracheobronchial lymph nodes 18
- 18. Posterior Mediastinum Boundaries: Ant. Pericardium,Bifurcation of trachea Post. T5 to T12 sup. Transverse thoracic plane Inf. diaphragm Sides: Mediastinal pleura 19
- 19. 20 Posterior Mediastinum Contents: Oesophagus Arteries ● DescendingAorta with its brs Veins ● Azygos ● Hemizygos ● Accessory hemizygos Nerves: ● Vagus ● Splanchnic nerves Thoracic duct lymph nodes ● Posterior mediastinal
- 20.
- 21. LENGTH:10-15 cm ❑ DIAMETER:2cm in males &1.5 cm in females ❑ Lined by ciliated columnar epithelium ❑Lower level at T6 on inspiration & T4 on expiration ❑ Made of c shape rings ❑ 2 rings per cm ❑ The rings make tube convex anterolateraly ❑ Posteriorly the gap is filled by trachealis muscle.
- 22. NERVE SUPPLY: ●LYMPHATIC DRAINAGE ⮚Pretracheal ⮚ paratracheal lymph node ● PARA SYMPHATHETIC: vagus & recurrent laryngeal nerves (sensory & secreto-motor to mucous membrane motor to trachealis muscle) ● SYMPHATHETIC: - middle cervical ganglion (vasomotor)
- 23. Blood supply ●ARTERIAL SUPPLY ●Uppertrachea ● Inferior thyroid artery ●Lower part ● Branches of the bronchial artery ●VENOUS DRAINAGE ●Upper part : left brachiocephalic vein ●Lower part: ● Inferior thyroid vein
- 24.
- 25.
- 26. 27 Tracheobronchial anatomy Tracheal DisplacementDue to Goiter
- 27. Clues to locatemass to mediastinum Mediastinal masses : Masses in the lung ❖ not contain air bronchograms ❖ mediastinal mass will create obtuse angles with the lung . ❖ Mediastinal lines will be disrupted – May contain air bronchograms – A lung mass abutts the mediastinal surface and creates acute angles with the lung
- 28. LEFT: A lungmass 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
- 29. Cervicothoracic sign ●The anteriormediastinum ends at the level of the clavicles. ●The posterior mediastinum extends much higher. ●Therefore ● any mass that remains sharply outlined in the apex of the thorax must be posterior and entirely within the chest, and ● any mass that disappears at the clavicles must be anterior and extends into neck
- 30. See sharp margin above clavicle Mass isin posterior mediastinum. because it remains sharply outlined in apex of thorax, indicating that it is surrounded by lung. This particular example is a ganglioneuroma
- 31. Thoracoabdominal sign ● Asharply marginated mediastinal mass seen through the diaphragm must lie entirely within the chest. ● The posterior costophrenic sulcus extends far more caudally than the anterior aspect of the lung ● Therefore ● Any mass that extends below the dome of the diaphragm and remains sharply outlined must be in the posterior compartments and surrounded by lung, and ● Any mass that terminates at dome of diaphragm must be anterior
- 32. Can you see the outlineof the mass below the diaphragm? Margin of mass is apparent and below diaphragm, therefore this must be in the middle or posterior compartments where it is surrounded by lung This example is a ‘Lipoma’
- 33. Hilum overlay sign ●Principle of hilum overlay ● An anterior mediastinal mass will overlap the main pulmonary arteries, therefore they will be seen within the margins of the mass
- 34. Hilum can be seen through mass thismust be an anterior mediastinal mass because it overlaps rather than “pushes out” the main pulmonary arteries This particular example is a thymoma
- 35.
- 36.
- 37.
- 38.
- 39.
- 40. MEDIASTINAL TUMORS EPIDEMOLOGY ● Mediastinalmalignancies are heterogenous in nature. ● most masses (> 60%) are: ● Thymomas ● Neurogenic Tumors ● Benign Cysts ● Lymphadenopathy (LAD) ● In children the most common (> 80%) are: ● Neurogenic tumors ● Germ cell tumors ● Foregut cysts ● In adults the most common are: ● Lymphomas ● LAD ● Thymomas ● Thyroid masses
- 41. Mediastinal Masses Compartment % Malignant Anterosuperior59 Middle 29 Posterior 16 Mediastin al division Most common tumors Anterior- superior thymoma middle lymphoma posterior Neurogenic tumors
- 42. Anterosuperior Masses Thymus • Thymoma •Thymic carcinoma • Thymic cyst • Thymic carcinoid • Thymolipoma Mediastinal Lymphoma • Hodgkin’s Lymphoma • Non-Hodgkin’s Lymphoma Mesenchymal tumors Germ Cell Tumor • Seminoma • Non seminomatous Germ Cell • Embryonal cell carcinoma • Endodermal sinus tumor • Choriocarcinoma • Teratoma • Mature • Immature Endocrine tumors • Thyroid tumors • Parathyroid adenoma
- 43. Middle mediastinal masses MediastinalLymphoma • Hodgkin’s Lymphoma • Non-Hodgkin’s Lymphoma Mesenchymal tumors CYST: • Bronchogenic cyst • Thoracic duct • Meningoceles Cardiac & pericardial tumors Tracheal tumors vascular tumors Lymphadenopathy • Inflammatory • Granulomatous • sarcoidosis
- 44. Posterior mediastinal masses MediastinalLymphoma • Hodgkin’s Lymphoma • Non-Hodgkin’s Lymphoma Mesenchymal tumors Neurogenic tumors • Peripheral nerves • Symphathetic ganglia • paraganglia ENDOCRINE TUMORS ESOPHAGEAL TUMORS & CYSTS
- 45. Tumors of thymus ●Thymomas ● Thymic carcinomas ● Thymic lymphomas ● Carcinoids ● Thymolipomas ● Secondaries
- 46. Thymoma Presentation ● Most commonprimary anterior mediastinal tumor ● M=F, most >40 ● Most patients are asymptomatic ● Half of patients suffer have associated parathymic syndromes • myasthenia gravis • hypogammaglobulinemia • pure red cell aplasia
- 47. ● 1/3 havechest pain, cough or dyspnea on presentation ● Myasthenia gravis occurs in 30-50% of pts with thymoma. Hypogammaglobulinemia occurs in 10% of pts with thymoma ● Pure red cell aplasia occurs in 5%, but thymoma occurs in 50% of pts with red cell aplasia
- 48. Thymoma ● lobulated massin the anterior mediastinum
- 49.
- 50. Invasive thymoma ● Encasementof mediastinal structures, infiltration of fat planes, and an irregular interface between the mass and lung parenchyma, are highly suggestive of invasion. ● Pleural thickening, nodularity, or effusion generally indicates pleural invasion by the thymoma
- 51. Thymic Carcinoid carcinoid tumors(neuroendocrine tumors) of the thymus are very rare, accounting for <5% of all neoplasms of the anterior mediastinum. They originate from the normal thymic Kulchitsky cells, which belong to the amine precursor uptake and decarboxylation (APUD) group Presentation ● men aged 30 to 50 years ● (male/female ratio: 3:1) ● Rarely associated with carcinoid syndrome ● Associated endocrine abnormalities: Cushing’s syndrome due to ectopic ACTH or MEN ● 73% have regional lymph node and/or distant osteoblastic bone mets
- 52. ● Thymic carcinoidtumor in a 22-year-old man with a 3-month history of a persistent dry cough. ● Contrast-enhanced CT scan shows a heterogeneously enhancing thymic mass . ● PET image shows intense FDG uptake by the mass
- 53. Thymic Carcinoma Presentation •M>F, 40s •Thymiccarcinomas are less common than thymomas, more aggressive with a higher propensity for capsular invasion •Early local invasion, widespread lymphatic and hematogenous metastases •Clinically, patients present initially with tussis, dyspnea, pleuritic chest pain, phrenic nerve palsy, or superior vena cava syndrome 80% of patients with thymic carcinoma may have radiographic evidence of invasion into adjacent structures in the mediastinum 40% may have evidence of mediastinal lymphadenopathy •Distant metastases to regional lymphatics, bone, liver, kidney, and lung are a common clinical feature
- 54. Thymic Carcinoma ● Thymiccarcinomas behave more aggressively than invasive thymomas and are more likely to metastasize to distant sites
- 55. Thymic Lymphomas ●Lymphoma isthe most common cause of an anterior mediastinal mass in children and the second most common cause of an anterior mediastinal mass in adults.
- 56. cancers of thehead and neck, abdomen, and pelvis can involve the thymus via lymphatic pathways ● Metastatic disease to the thymus in a 10-year-old boy 2 years after diagnosis of alveolar rhabdomyosarcom a of the thigh. Secondary Tumors of the Thymus
- 57.
- 58. Primary Mediastinal Lymphoma ●5-10% of patients with lymphoma present with primary mediastinal lesions ● Primary mediastinal lymphoma represents 10-20% of primary mediastinal masses in adults and are usually in the anterosuperior compartment ● Usually present with fever, weight loss and night sweats ● Pain, dyspnea, stridor, SVC syndrome due to mass effects are uncommon
- 59. Primary Mediastinal Lymphoma TwoTypes ● Primary Mediastinal Hodgkin’s Lymphoma ● Primary Mediastinal Non-Hodgkin’s Lymphoma • Poorly differentiated lymphoblastic • Diffuse lymphocytic • Primary Mediastinal B-cell Lymphoma
- 60. Primary Mediastinal Hodgkin’sLymphoma Presentation ● Incidental mediastinal mass on chest xray is 2nd most common presentation after asymptomatic lymphadenopathy ● Mass is usually large, rarely causes retrosternal chest pain, cough, dyspnea, effusions or SVC syndrome ● Bimodal age distribution ● “B” symptoms: fever, weight loss (>10% body wt in 6 months), night sweats ● Generalized pruritus present
- 61. A chest CTexam shows the mass to extend from the neck to the diaphragm, compressing the tracheal and left mainstem bronchus leading to left lower lobe atelectasis. The chest wall mass is partially eroding the sternum. Dx:Lymphoma, Hodgkin, Anterior Mediastinal, Sternal Involvement
- 62. Two contiguous slices froman enhanced chest CT exam show a homogenous, solid, anterior mediastinal mass and a large right pleural effusion. Dx-Lymphoma Non-Hodgkin, Anterior Mediastinal
- 63. Mediastinal Germ CellTumors ● Primary extragonadal germ cell tumors comprise 2% to 5% of all germ cell tumors ● Approximately two thirds of these tumors occur in the mediastinum ● The mediastinum is the most common site of primary extragonadal germ cell tumors in young adults ● Represent 10-15% of adult anterosuperior mediastinal tumors
- 64. ● they presumablyarise from germ cells that migrate along the urogenital ridge during embryonic development . ● The embryologic urogenital ridge extends from C6 to L4 and after malignant transformation of displaced germ cells, explains the development of primary germ cell tumors outside the gonads Mediastinal Germ Cell Tumors
- 65. Mediastinal Germ CellTumors Three types ● Teratoma ● Seminoma ● Nonseminomatous Germ Cell Tumor
- 66. Mediastinal Teratomas ● Mostcommon mediastinal germ cell tumor ● Three types: • Mature: benign, well-differentiated • Immature: contains >50% immature components, may recur or metastasize • Malignant: a mature teratoma that contains a focus of carcinoma, sarcoma or malignant GCT
- 67. Mature Teratoma ● Occursin children and young adults ● Usually asymptomatic, but if large enough, may cause chest pain, dyspnea, cough or other symptoms of mediastinal compression ● Contains derivatives of all three primitive germ layers including • Ectoderm: teeth, skin, hair • Mesoderm: cartilage and bone • Endoderm: bronchial, intestinal and pancreatic tissue ● Expectoration of hair (trichoptysis) is rare but pathognomonic
- 68. Dx Teratoma, Anterior Mediastinal CTexam show a low density mass in the anterior mediastinum with irregular walls with calcium in it.
- 69. Mediastinal Seminoma ● Represents40% of malignant mediastinal GCTs ● Afflicts Caucasian men in 20s-30s ● Only rarely represents a metastatic lesion from a testicular primary tumor, but testicular USG is usually performed to rule this out ● If any other germ cell tumor histology is identified in the tumor, it is treated as a mixed NSGCT ● AFP normal, β-HCG may be elevated in 10%
- 70. Mediastinal Seminoma Presentation ● Slowgrowing tumor, usually symptomatic at diagnosis ● Commonly presents with chest pain, dyspnea, cough, weight loss ● Presents infrequently with SVC syndrome ● Bulky, lobulated, homogeneous mass, no calcifications ● Usually not invasive, but many have metastasized to regional lymph nodes, lung and/or bone by the time of diagnosis
- 71. Mediastinal Nonseminomatous Germ CellTumors ● Five Types • Embryonal cell carcinoma • Endodermal sinus tumor: elevated AFP • Choriocarcinoma: elevated β-HCG • Malignant Teratoma • Mixed
- 72. Mediastinal Nonseminomatous Germ CellTumors ● NSGCTs of the mediastinum have a worse prognosis than mediastinal seminomas or teratomas ● Occur in men in the 20-40 age group ● 20% of patients also have Klinefelter’s syndrome
- 73. Tracheal tumors ● Extremelyrare tumors. ● Comprise of 0.1 to 0.4 %of all diagnosed malignancies ● Two types: squamous cell carcinoma M:F=3:1 Age:6th decade adenoid cystic carcinomas M:F=1:1 younger age ● Clinical feature: cough, dysnoea, dysphagia,stridor hemoptysis, dysphonia
- 74.
- 75. Clinical Presentation ● Asymptomaticmass ● Incidental discovery – most common ● 50% of all mediastinal mass are asymptomatic ● 80% of such mass are benign ● More than half are malignant if with symptoms
- 76. Clinical Presentation 1Effects onCompression or invasion of adjacent tissues ⮚ Chest pain, from traction on mediastinal mass, tissue invasion, or bone erosion is common ⮚ Cough, because of extrinsic compression of the trachea or bronchi, or erosion into the airway itself ⮚ Hemoptysis, hoarseness or stridor ⮚ Pleural effusion, invasion or irritation of pleural space ⮚ Dysphagia, invasion or direct invasioin of the esophagus ⮚ Pericarditis or pericardial tamponade ⮚ Right ventricular outflow obstruction and cor pulmonale
- 77. Clinical Presentation 2Effects onCompression of nerves Hoarseness, invading or compressing the nerves recurrent laryngeal nerve ● Horners syndrome, involvement of the sympathetic ganglia ● Dyspnea, from phrenic nerve involvement causing diaphragmatic paralysis ● Tachycardia, secondary to vagus nerve involvemenT
- 78. Clinical Presentation ● Superiorvena cava ● Vulnerable to extrinsic compression and obstruction because it is thin walled and its intravascular pressure is low. ● Superior vena cava syndrome ● Results from the increase venous pressure in the upper thorax , head and neck ● characterized by dilation of the collateral veins in the upper portion of the head and thorax and edema oand phlethora of the face, neck and upper torso, suffusion and edema of the conjunctiva and cerebral symptoms such as headache, disturbance of consciousness and visual distortion ● Bronchogenic carcinoma and lymphoma are the most common etiologies
- 79. Clinical Presentation ● Systemicsymptoms and syndromes ● Fever, anorexia, weight loss and other non specific symptoms of malignancy .
- 80. Mediastinal mass: pretreatment evaluation
- 84.
Editor's Notes
- #47 1/3 have chest pain, cough or dyspnea on presentation Myasthenia gravis occurs in 30-50% of pts with thymoma. All pts should have antiacetylcholine receptor antibodies measured prior to surgery and subsequently Hypogammaglobulinemia occurs in 10% of pts with thymoma Pure red cell aplasia occurs in 5%, but thymoma occurs in 50% of pts with red cell aplasia