imaging the mediastinum
TRANSCRIPT
![Page 1: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/1.jpg)
Imaging the Mediastinum
![Page 2: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/2.jpg)
MediastinumMediastinum Bounded laterally by parietal pleura of each lung Superior margin is thoracic inlet
Defined by plane of 1st ribs Inferior margin is diaphragm Tissue planes extend superiorly into neck
around great vessels, trachea and esophagus Connects to abdominal cavity via esophageal,
caval and aortic hiatuses Connects to lungs along hilar vessels and
bronchi
![Page 3: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/3.jpg)
MediastinumMediastinum Radiologic anatomy
CXR CT
Normal or not? Compartments and their pathologies:
Anterior Middle Posterior
![Page 4: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/4.jpg)
Radiologic AnatomyRadiologic Anatomy
Landmarks to look for on the chest radiograph: Trachea Paratracheal stripe Descending aortic contour Azygo-esophageal contour
![Page 5: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/5.jpg)
Pneumomediastinum with Pneumomediastinum with cervical emphysemacervical emphysema
![Page 6: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/6.jpg)
Tracheal air columnTracheal air column
Should be straight
Slight bend to right due to aortic arch on its left.
![Page 7: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/7.jpg)
Trachea deviates to the left
![Page 8: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/8.jpg)
Right Aortic ArchRight Aortic Arch
![Page 9: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/9.jpg)
Right paratracheal stripeRight paratracheal stripe
Extends from thoracic inlet to azygos vein
Widens out at azygos vein
No more than 3-4 mm thick
![Page 10: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/10.jpg)
Aortic contourAortic contour
![Page 11: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/11.jpg)
Azygo-esophageal recessAzygo-esophageal recess
![Page 12: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/12.jpg)
Aortic contour and azygo-esophageal Aortic contour and azygo-esophageal recess abnormalrecess abnormal
![Page 13: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/13.jpg)
Normal anatomy:Normal anatomy:CT/CXR correlationCT/CXR correlation
![Page 14: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/14.jpg)
Normal anatomy:Normal anatomy:CT/CXR correlationCT/CXR correlation
![Page 15: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/15.jpg)
Normal anatomy:Normal anatomy:CT/CXR correlationCT/CXR correlation
![Page 16: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/16.jpg)
Normal anatomy:Normal anatomy:CT/CXR correlationCT/CXR correlation
![Page 17: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/17.jpg)
Is the mediastinum wide?Is the mediastinum wide? First ask… is it technical?
Positioning: rotated:? AP? Lordotic? Supine?
Inspiration If so, repeat the film before proceeding to CT.
Then ask…Is it new? GET OLD FILMS before getting a CT unless
time is critical.
![Page 18: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/18.jpg)
Think about normal variants!Think about normal variants!
Vascular structures Aortic anomalies Tortuous vessels Azygos vein
Lipomatosis Fat pads
![Page 19: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/19.jpg)
Severe asthma on long term steroids
![Page 20: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/20.jpg)
Mediastinal lipomatosisMediastinal lipomatosis
![Page 21: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/21.jpg)
![Page 22: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/22.jpg)
Pericardial Fat PadPericardial Fat Pad
![Page 23: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/23.jpg)
![Page 24: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/24.jpg)
Tortuous brachiocephalic Tortuous brachiocephalic vesselsvessels
![Page 25: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/25.jpg)
70 year old with dysphagia70 year old with dysphagia
Tracheal air
column
![Page 26: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/26.jpg)
Esophageal cancer
![Page 27: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/27.jpg)
Abnormal right paratracheal stripe
Hodgkins Hodgkins diseasedisease
![Page 28: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/28.jpg)
Abnormal right paratracheal stripe
![Page 29: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/29.jpg)
Check the old film!Check the old film!
2 days earlier
Hematoma from line insertion
![Page 30: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/30.jpg)
Air fluid levelsAir fluid levels Think bowel or abscess:
Hiatal hernia Zenker diverticulum Epiphrenic diverticulum Achalasia Mediastinal abscess
![Page 31: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/31.jpg)
AchalasiaAchalasia
![Page 32: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/32.jpg)
Zenker diverticulumZenker diverticulum
![Page 33: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/33.jpg)
Hiatal herniaHiatal hernia
![Page 34: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/34.jpg)
Mediastinal abscess after Mediastinal abscess after CABGCABG
![Page 35: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/35.jpg)
Differential diagnosis of Differential diagnosis of mediastinal massesmediastinal masses
Traditionally, we divide the mediastinum into compartments.
Likely diagnosis of mass depends on what is contained in each compartment
These are not anatomic boundaries, and masses commonly cross over into compartments where they don’t “belong”.
![Page 36: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/36.jpg)
Posterior mediastinumPosterior mediastinum Paraspinal area Masses usually visible
on lateral film overlying spine
May obscure descending aorta contour
![Page 37: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/37.jpg)
Posterior mediastinumPosterior mediastinum Neurogenic tumors
Schwannoma Sympathetic nerve tumors
e.g. ganglioneuroma Neurenteric cyst, lateral
meningocele Lymph nodes (unusual
as only area involved) Extramedullary
hematopoesis Vertebral tumors, spurs
![Page 38: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/38.jpg)
SchwannomaSchwannoma
![Page 39: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/39.jpg)
Extramedullary hematopoesisExtramedullary hematopoesis
Chronic anemias, myelodysplasias
![Page 40: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/40.jpg)
Lateral meningocele in NF-1Lateral meningocele in NF-1
![Page 41: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/41.jpg)
Anterior mediastinumAnterior mediastinum Space anterior to
great vessels and heart, behind the sternum
![Page 42: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/42.jpg)
Anterior mediastinumAnterior mediastinum Most common:
Lymphoma Thymic lesions Germ cell origin tumors Thyroid masses
Also: Foregut cysts, nerve tumors, aortic aneurysm,
etc.
![Page 43: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/43.jpg)
Anterior mediastinal massesAnterior mediastinal masses
thymic hyperplasia teratocarcinoma
teratoma lymphoma
thymoma
hemorrhage
![Page 44: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/44.jpg)
Middle mediastinumMiddle mediastinum Contains heart, great
vessels, esophagus, trachea, lymph nodes, nerves.
CXR abnormality in paratracheal area, azygo-esophageal recess, retrocardiac area
May be difficult to see on lateral view
![Page 45: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/45.jpg)
Middle MediastinumMiddle Mediastinum
Lymph nodes Foregut cysts Vascular lesions e.g. aneurysm Bronchogenic carcinoma Hiatal hernia, other esophageal or GI
lesions
![Page 46: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/46.jpg)
Lymphoma Lymphoma
![Page 47: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/47.jpg)
Cardiac evaluationCardiac evaluation Remember: cardiothoracic ratio of about
0.5 applies only to good PA chest x-rays. Knowing which chambers form which
cardiac contours can help identify what is enlarged.
Look for accompanying signs: Pulmonary venous engorgement and isolated
LA enlargement suggests mitral stenosis. Dilated aorta and LV enlargement suggests
aortic valve insufficiency.
![Page 48: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/48.jpg)
Normal heart contoursNormal heart contours
Left atrium
Left ventricle
Right atrium
![Page 49: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/49.jpg)
Left atrial enlargement-mitral Left atrial enlargement-mitral stenosisstenosis
Mitral valve
![Page 50: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/50.jpg)
Left atrial enlargementLeft atrial enlargement
“Double density”
Straightened left heart border LA enlarged
LV normal
![Page 51: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/51.jpg)
Enlarged ascending aorta in ASEnlarged ascending aorta in AS
![Page 52: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/52.jpg)
Calcific Aortic StenosisCalcific Aortic Stenosis Enlarged ascending aorta, normal arch,
normal overall heart size
LVH
![Page 53: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/53.jpg)
LV enlargementLV enlargement
![Page 54: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/54.jpg)
Dilated cardiomyopathy Dilated cardiomyopathy multichanber enlargementmultichanber enlargement
![Page 55: Imaging the Mediastinum](https://reader035.vdocument.in/reader035/viewer/2022062412/577ccf461a28ab9e788f56a4/html5/thumbnails/55.jpg)
The EndThe End