PPT on madiastinal lines seen on chest x ray

1. MADIASTINAL LINES
DR ANANYA GOSWAMI
Department of Radio Diagnosis
SMS Medical college Jaipur

2. MADISTINAL LINES
• 1.Anterior junction line
• 2.Posterior junction line
• 3.Para aortic line
• 4.Right paratracheal line
• 5.Azygo oesophagus line
• 6.Para esophgeal lines
• 7. Right para spinal line
• 8.Left para spinal line
• 9.Aorto pulmonary line
• 10. Pre aortic line

3. MADISTINAL LINES
1. Anterior junction (madistinal )line.
The anterior pleural reflections give rise to the
anterior junction line, together with the
superior and inferior recesses. The superior
recesses are produced by the anterior aspects of
the
lungs contacting the mediastinum behind the
manubrium sterni. The line itself is formed by the
apposition of the two lungs, together with their
respective pleural coverings and the thin layer of
mediastinum in this area. It lies retrosternally, and is
usually inclined downwards and to the left
(rarely to the right). Inferiorly the diverging lungs
form the inferior recesses

4. MADISTINAL LINES
1. Anterior junction (madistinal )line.(contd)
The anterior junction line may be widened by mediastinal fat or an
anterior mediastinal mass, such as a goiter, a tumor arising within the thymus
or an enlarged aortic arch. The size of the thymus in young children accounts
for them not having a visible line.
Obliteration or opacity on one side of the line may occur with adjacent lung
consolidation or collapse, or from adjacent pleural fluid. Conversely a
pneumothorax may accentuate the line. Movement of the line commonly
occurs with lung or lobar collapse. Movement with left or right upper lobe
collapse. Movement may also occur with right lower lobe collapse - 'the
upper triangle sign'

5. MADISTINAL LINES
Anterior junction (madistinal )line.(contd)
'the upper triangle sign'

6. MADISTINAL LINES
• Anterior junction (madistinal )line.(contd)
Anterior lung herniation' may be seen with collapse or reduced volume of the left lung
or upper lobe and is due to compensatory hyper expansion of the right upper lobe and the
movement of the anterior junction anatomy to the left lung and pulmonary artery
hypoplasia . When there is a deep anterior mediastinum, as with emphysema, an anterior
mediastinal mass may only occupy part of the anterior mediastinum, and then a normal line
may not exclude the presence of a small mass.
The superior recesses, which reflect off the great vessels, commonly project lateral to the
manubrium sterni, but the lower parts of these usually lie behind it. The superior recesses
are best shown on tomograms, but may also be seen on oblique views of the upper
mediastinum or sternum. Normally the superior recesses bound mediastinal fat, but goitres
or dilatations of the innominate veins etc. may displace them laterally. The superior
recesses may be further apart on supine radiographs or those taken in expiration
anterior junction line does not extend above the level of the supra-sternal notch.
The inferior recesses are somewhat variable in appearance, although they are usually
oblique and straight. With much mediastinal fat or ' fat pads ' they may become convex.
Similarly they may be displaced by pericardial cysts, very large internal mammary nodes,
etc.

7. MADISTINAL LINES
2.Posterior junction line(stripe)
The posterior junction
anatomy, like the
anterior, comprises the
posterior junction line,
together with its
superior and inferior
recesses . It lies higher
than the anterior
junction line

8. MADISTINAL LINES
• 2.Posterior junction line(stripe)(contd)
The superior recesses are formed by the two lungs approaching the mediastinum in
front of Dl and D2 vertebral bodies. The line is due to the double layer of left and
right parietal pleura overlying D3 to D5 vertebrae, and lying behind the oesophagus.
The inferior recesses are formed by the lungs diverging from the midline, due to the
forward arching of the right and left superior intercostal vein, the posterior parts of
the azygos vein and the aortic arch. The right inferior recess lies lower than the left.
The depth of the space between the spine and the oesophagus is variable in different
subjects and is also affected by the degree of expansion of the lungs and the amount
of fat present. When widened by fat, or the oesophagus itself, the line may appear as
a stripe. It may also be widened when the two sides are deviated by a mediastinal
abscess or haematoma. It usually overlies the tracheal air column, and is often
slightly concave to the right

9. MADISTINAL LINES
• 2.Posterior junction line(stripe)(contd)
•
Grossly widened line or stripe seen
due to an abscess or haematoma.

10. MADISTINAL LINES
• 2.Posterior junction line(stripe)(contd)
Deformed superior and inferior
recesses - a convex superior
recess usually indicates pressure
from a superior mediastinal
mass. Similarly a concave
inferior recess may indicate an
overlying mass.

11. MADISTINAL LINES
• 3.Para aortic line
This follows the line of the
descending aorta on its left side.
Its presence depends on aerated
left lung and particularly an
aerated left lower lobe being
adjacent to it. Like the para-
oesophageal line,it is a very
important landmark in the chest,
and is well seen on high KV
radiographs

12. MADISTINAL LINES
• 3.Para aortic line(contd)
Displacement of the line may be seen with aortic
abnormalities, masses arising in the spine and
creeping around the descending aorta, or other
masses such as a sympathetic chain neurinoma, etc.
Loss of the line is usually due to consolidation or
collapse in the adjacent lung, usually the left lower
lobe. It may also be lost with a posteriorly situated
pleural effusion, an adjacent tumour, a leaking
aneurysm or an abscess e.g. resulting from
oesophageal perforation, etc. It is also lost when the
mediastinum is squashed, particularly by the left
inferior pulmonary vein, as with pectus excavatum . It
is also partially lost in thin people, in whom the aorta
tends to be buried' in the mediastinum .
Partial loss also may occur with adjacent tumour or
due to contact of part of the aorta with normal
structures.

13. MADISTINAL LINES
4.Right para tracheal line
normally this is from 1 to 4 mm thick
(average 2mm). It extends from the
thoracic inlet to the right tracheo-
bronchial angle, and it is formed by
the tracheal wall, interstitial
mediastinal tissue and adjacent
pleura. Thickening may be due to
adjacent fat, but is often good
evidence of local adjacent disease
such as lymphadenopathy, infection
or haemorrhage, pleural thickening
or thickening of the tracheal wall.

14. MADISTINAL LINES
4.Right para tracheal
line(contd)
Right para tracheal line should always be
looked for on frontal radiographs, and is
a particularly valuable sign following
severe trauma, since a normal right
para-tracheal stripe usually implies that
there is no adjacent haematoma, and
therefore that a serious vascular injury is
unlikely.Loss of the line occurs with
opacification of the adjacent lung i.e.
consolidation or collapse of the right
upper lobe, or from adjacent pleural
fluid.

15. MADISTINAL LINES
• 5.Azygo oesophagus line
• anterior border of
azygoesophageal line formed
by the left atrium, superior
border formed by the azygos
vein and posterior border
formed by the thoracic spine
Azygoesoph
agus line- 

16. MADISTINAL LINES
• 6.Para esophgeal
lines
• It is formed by the
interface between the air-
filled right lung and the
posterior mediastinum,
often adjacent to the mid
and lower oesophagus
paraesophageal line----

17. MADISTINAL LINES
• 7.Rightpara
spinal line
• The right
paraspinal line
appears straight
and runs from the
8th through the
12th thoracic
vertebral levels.

18. MADISTINAL LINES
• 8.Left para
spinal line
• The left paraspinal
line runs vertically
from the aortic arch
to the diaphragm
and lies medial to
the paraortic line,
although sometimes
it can lie lateral to
the paraortic line

19. MADISTINAL LINES
• 9.Aorto pulmonary
line
• Extending obliquely
downwards to the left. it
arises supero-medially,
crosses the aortic knuckle
and merges inferiorly with
the pulmonary artery and/
or the heart.
-aortppulmonary
line

20. MADISTINAL LINES
• 10. Pre aortic line
• is due to the left lower
lobe tucking into the
aorto-pulmonary
window, behind the left
lower lobe bronchus
and behind the heart. It
is often seen to extend
down as far as Dl0.
Pre aortic line--->