Slide 1

RadiographicInterpretation in theMediastinumRadiographicInterpretation in theMediastinum

Adam Guttentag M.D.Adam Guttentag M.D.

MediastinumMediastinum

Radiologic anatomyRadiologic anatomy

CXRCXR

CTCT

Normal or not?Normal or not?

Compartments and their pathologies:Compartments and their pathologies:

AnteriorAnterior

MiddleMiddle

PosteriorPosterior

Mediastinal AnatomyMediastinal Anatomy

Bounded laterally by parietal pleura ofeach lungBounded laterally by parietal pleura ofeach lung

Superior margin is thoracic inletSuperior margin is thoracic inlet

Defined by plane of 1st ribsDefined by plane of 1st ribs

Inferior margin is diaphragmInferior margin is diaphragm

Tissue planes extend superiorly intoneck around great vessels, trachea andesophagusTissue planes extend superiorly intoneck around great vessels, trachea andesophagus

Connects to abdominal cavity viaesophageal, caval and aortic hiatusesConnects to abdominal cavity viaesophageal, caval and aortic hiatuses

Connects to lungs along hilar vesselsand bronchiConnects to lungs along hilar vesselsand bronchi

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Radiologic AnatomyRadiologic Anatomy

Landmarks to look for onthe chest radiograph:Landmarks to look for onthe chest radiograph:

TracheaTrachea

Paratracheal stripeParatracheal stripe

Junction linesJunction lines

Descending aortic contourDescending aortic contour

Azygo-esophageal contourAzygo-esophageal contour

Tracheal air column

Should be straightShould be straight

Slight bend toright due to aorticarch on its left.Slight bend toright due to aorticarch on its left.

Right Aortic ArchRight Aortic Arch

70 yo with dysphagia70 yo with dysphagia

Esophageal CarcinomaEsophageal Carcinoma

Zenker DiverticulumZenker Diverticulum

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Erect CXR

Right paratracheal stripe

Extends fromthoracic inlet toazygos vein

Widens out atazygos vein

No more than 3-4mm thick

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SarcoidSarcoid

Old film

Hodgkins diseaseHodgkins disease

Aortic ContourAortic Contour

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HoarseHoarse

One year ago

Lung CancerLung Cancer

Chronic CoughChronic Cough

Azygo-esophageal recessAzygo-esophageal recess

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Bronchogenic CystsBronchogenic Cysts

Anterior junction lineAnterior junction line

Extends from thoracic inletinferiorly and to the leftExtends from thoracic inletinferiorly and to the left

Widens superiorlyWidens superiorly

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Anterior PneumothoraxAnterior Pneumothorax

Posterior Junction LinePosterior Junction Line

Not always seenNot always seen

Usually in emphysemaUsually in emphysema

Extends inferiorly to thelevel of the aortaExtends inferiorly to thelevel of the aorta

Widens superiorly tooutline apices of lungsWidens superiorly tooutline apices of lungs

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Wide Mediastinum???Wide Mediastinum???

First ask…First ask…

Is it technical?Is it technical?

PositioningPositioning

rotated:?rotated:?

AP?AP?

Lordotic?Lordotic?

Supine?Supine?

InspirationInspiration

If so, repeat the film before proceeding to CT.If so, repeat the film before proceeding to CT.

Then ask…Then ask…

Is it new?Is it new?

GET OLD FILMS before you get a CT scan unless timeis critical..GET OLD FILMS before you get a CT scan unless timeis critical..

30 year old man in motor vehicle accident

AP supine

AP upright

PA upright

Think about normal variants!Think about normal variants!

Vascular structuresVascular structures

Aortic anomaliesAortic anomalies

Tortuous vesselsTortuous vessels

Azygos veinAzygos vein

LipomatosisLipomatosis

Fat padsFat pads

Severe asthma on longterm steroids

Mediastinal Lipomatosis

Pericardial Fat Pad

Tortuous brachiocephalic vesselsTortuous brachiocephalic vessels

Azygos continuation of the IVCAzygos continuation of the IVC

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Apical Aortic ArchApical Aortic Arch

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Check the old film!Check the old film!

Recent CVC stickRecent CVC stick

2 days earlier

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$G:\photos\mediastinum\lymphoma of pericardium parkins\pa baseline.jpg$

One year earlier

Pericardial LymphomaPericardial Lymphoma

$G:\photos\mediastinum\lymphoma of pericardium parkins\ct7.jpg$

Special case:Air fluid levelsSpecial case:Air fluid levels

Think bowel or abscess:Think bowel or abscess:

Hiatal herniaHiatal hernia

Zenker diverticulumZenker diverticulum

Epiphrenic diverticulumEpiphrenic diverticulum

AchalasiaAchalasia

Mediastinal abscessMediastinal abscess

AchalasiaAchalasia

Hiatal herniaHiatal hernia

Epiphrenic diverticulumEpiphrenic diverticulum

Mediastinal abscess after CABGMediastinal abscess after CABG

Mediastinal CompartmentsMediastinal Compartments

Arbitrary division of contiguous spaces,especially anterior and middle compartmentsArbitrary division of contiguous spaces,especially anterior and middle compartments

Useful in grossly narrowing differential diagnosisUseful in grossly narrowing differential diagnosis

Often significant crossing of compartmental“boundaries”, making classification difficult.Often significant crossing of compartmental“boundaries”, making classification difficult.

Anterior mediastinumAnterior mediastinum

Space anterior to greatvessels and heart,behind the sternumSpace anterior to greatvessels and heart,behind the sternum

Anterior mediastinumAnterior mediastinum

Most common:Most common:

Thymic lesionsThymic lesions

Germ cell origin tumorsGerm cell origin tumors

+/- Thyroid masses+/- Thyroid masses

LymphomaLymphoma

MetastasesMetastases

Also:Also:

Foregut cysts, nerve tumors, aortic aneurysm, etc.Foregut cysts, nerve tumors, aortic aneurysm, etc.

Anterior mediastinal massesAnterior mediastinal masses

Thymic hyperplasia

teratocarcinoma

teratoma

lymphoma

thymoma

hemorrhage

Middle MediastinumMiddle Mediastinum

Contains heart, greatvessels, esophagus,trachea, lymph nodes,nerves.Contains heart, greatvessels, esophagus,trachea, lymph nodes,nerves.

CXR abnormality inparatracheal area,azygo-esophagealrecess, retrocardiac areaCXR abnormality inparatracheal area,azygo-esophagealrecess, retrocardiac area

May be difficult to seeon lateral viewMay be difficult to seeon lateral view