GET AN IDEA ABOUT LOCALIZATION OF MEDIASTINAL MASSES ON CHEST XRAYS AND DIFFERENTIAL DIAGNOSIS

2.  In any method used to divide the mediastinum,
the divisions are theoretic rather than physical.
Therefore, disease can spread from one
compartment to another, and some diseases do
not occur exclusively in any one compartment.

6.  Anterior junction line
(AJL) formed by the
anterior apposition of
the two lungs together
with their respective
pleuralcoverings and
a thin layer of
mediastinal tissue

8.  ALWAYS CONCAVE
OR FLAT TOWARDS
THE LUNG
 CONVEX =
ABNORMAL

10.  It is formed by the
contact of the posterior
aspects of the left and
right lungs behind the
esophagus creating a
sagittal pleural interface
 Contrary to the anterior
junction line, it extends
cranially above the
sternoclavicular notch.

12.  NORMAL
THICKNESS 1-4 MM
 > 5MM IS
ABNORMAL

14.  Azygoesophageal Line ,
Situated behind the heart
and the mediastinum and
formed by the interface
between the air-filled right
lower lobe and the
posterior mediastinal
tissue laterally from the
mid and lower third of the
esophagus
 It describes an “inverted
S” curve and joins the
azygos arch and the right
Paratracheal lines above
the azygoesophageal
recess

16.  The para-aortic line
follows the
Descending aorta on
the left side.
 It is formed by the
interface with the
aerated lower left
lobe.

18.  Paraspinal lines are
formed on both sides
by the tangential
contact of the lungs
and the pleura with
the posterior
Paravertebral soft
tissues

19.  WHERE IS THE
MASS LOCATED
AND WHY?

20.  HILUM OVERLAY
SIGN POSITIVE
 DESCENDING
AORTA NOT
OBSCURED
 MASS IS IN
ANTERIOR MED

23.  PERICARDIAL CYST
 70% ARE LOCATED
AT RIGHT
CARDIOPHRENIC
ANGLE
 WELL DEFINED
WALL
 MAY BE CALCIFIED

24.  MORGAGNIAN
HERNIA
 AIR WITHIN THE
BOWEL LOOPS
HELPS IN
DIFFERENTIATING