This document discusses pulmonary vasculature abnormalities including pulmonary artery hypertension, pulmonary edema, pulmonary embolism, and venous abnormalities. It provides definitions, classifications, risk factors, and radiographic findings for each condition. For pulmonary artery hypertension, the document describes the definition, etiology, classification systems, and findings on plain radiography, CT, and MRI. It also discusses pulmonary edema, pulmonary embolism, pulmonary arteriovenous malformations, pulmonary varices, and pulmonary venoocclusive disease.

1. Chest
Pulmonary Vasculature

2. Mohamed Zaitoun
Assistant Lecturer-Diagnostic Radiology
Department , Zagazig University Hospitals
Egypt
FINR (Fellowship of Interventional
Neuroradiology)-Switzerland
zaitoun82@gmail.com

5. Knowing as much as
possible about your enemy
precedes successful battle
and learning about the
disease process precedes
successful management

6. Pulmonary Vasculature
a) Pulmonary Artery Hypertension
b) Pulmonary Edema
c) Pulmonary Embolism
d) Venous Abnormalities

7. a) Pulmonary Artery Hypertension :
1-Definition
2-Etiology
3-Classification
4-Radiographic Findings

8. 1-Definition :
-PAH is defined as P-systolic > 30 mm Hg or P-
mean > 25 mm Hg
-Normal pulmonary artery pressures in adults :
P-systolic = 20 mm Hg
P-diastolic = 10 mm Hg
P-mean = 14 mm Hg
Capillary wedge pressure = 5 mm Hg

9. 2-Etiology :
a) Primary PAH (females 10-40 years , rare)
b) Secondary PAH (more common) :
1-Eisenmenger's syndrome
2-Chronic PE
3-Emphysema , pulmonary fibrosis
4-Schistosomiasis (most common cause
worldwide)

10. 3-Classification :
a) Precapillary Hypertension :
1-Vascular :
-Increased flow : L-R shunts
-Chronic PE
-Vasculitis
-Drugs
-Idiopathic
2-Pulmonary :
-Emphysema
-Interstitial Fibrosis
-Fibrothorax , chest wall deformities
-Alveolar hypoventilation

11. b) Postcapillary Hypertension :
1-Cardiac :
-LV failure
-Mitral stenosis
-Atrial Tumor
2-Pulmonary Venous :
-Idiopathic venocclusive disease
-Thrombosis

12. 4-Radiographic Findings :
a) Plain Radiography
b) CT
c) MRI

13. a) Plain Radiography :
-The classic radiographic findings of pulmonary
hypertension are evident only late in the disease
process :
1-Central pulmonary arterial dilatation
2-Cardiomegaly (enlarged right ventricle & atrium)
3-Calcification of the pulmonary arteries is
pathognomonic but occurs late in the disease

14. (a) Frontal chest radiograph shows a prominent main pulmonary artery (arrow) , dilated
right interlobar artery (arrowhead) and pruning of peripheral pulmonary vascularity ,
(b) Lateral chest radiograph shows filling of the retrosternal airspace (arrow) a result
of right ventricular dilatation , the right ventricle is in contact with more than one-third
of the distance from the sternodiaphragmatic angle (black arrowhead) to the point
where the trachea meets the sternum (white arrowhead)

15. Yellow arrow shows enlarged right main pulmonary artery ,
red arrow shows the enlarged left pulmonary artery

17. b) CT :
-Vascular , cardiac and parenchymal
1-Vascular :
-Enlarged main PA (diameter correlates with pressure) :
>29 mm is indicative of PAH
-Rapid tapering of PA towards the periphery
-If the ratio of pulmonary artery diameter to aortic diameter
is greater than 1 (rPA >1) by CT , there is a strong
correlation with elevated mean PA pressure , particularly
in patients <50 years of age
-Calcification of the pulmonary arteries is pathognomonic
but occurs late in the disease

18. 2-Cardiac :
-Cardiomegaly (enlarged right ventricle &
atrium)
-Dilatation of the inferior vena cava and
hepatic veins and pericardial effusion
-Contrast material reflux into the inferior
vena cava and hepatic veins , a result of
elevated right heart pressures also may be
seen

19. 3-Parenchymal :
-Both primary and secondary forms of pulmonary
hypertension may produce a mosaic pattern of
lung attenuation , a finding suggestive of
regional variations in parenchymal perfusion ,
vascular cause for the mosaic pattern is
suggested when areas of high attenuation
contain larger-caliber vessels and areas of low
attenuation contain vessels of diminished size

20. -Vascular signs of
pulmonary hypertension
-Axial multidetector CT
angiogram shows
dilatation (29 mm or
more) of the main
pulmonary artery
-The ratio of the main
pulmonary arterial
diameter to that of the
ascending aorta is also
greater than or equal to 1,
another useful sign of
pulmonary hypertension

21. -(A) Markedly enlarged
pulmonary arteries with
tiny branching smaller
vessels
-(B) Enlarged right ventricle
and the smaller left
ventricle , the septum is
pushed towards the left
ventricle due to very high
pressure inside the right
ventricle

23. Cardiac features of pulmonary hypertension. (a) CTA shows that the right ventricular myocardium
(white arrow) is more than 4 mm thick , a finding consistent with right ventricular hypertrophy.
Straightening of the interventricular septum (black arrow) also is seen. (b) CTA shows right
ventricular dilatation which is defined as a diameter ratio (the ratio of the right ventricular diameter
[black arrow] to the left ventricular diameter [white arrow]) greater than 1:1 at the midventricular
level , Leftward bowing of the interventricular septum also is seen. (c) CTA shows reflux of
contrast material into the inferior vena cava which is dilated and hepatic veins (arrow)

24. c) MRI :
-Morphologic cardiac changes include right
ventricular dilatation and hypertrophy ,
right atrial enlargement , flattening of the
interventricular septum or leftward bowing
& tricuspid regurgitation
-Decreased velocity of pulmonary flow by
MRA

25. b) Pulmonary Edema :
1-Etiology
2-Radiographic Features

26. 1-Etiology :
1-Cardiogenic : (any cause of impaired left ventricular function)
-LVF , MR
2-Renal :
-RF , volume overload
3-Lung Injury :
-Septic shock , neurogenic shock
-Fat embolism
-Aspiration , drowning
4-Cerebral Diseases :
-Cerebrovascular accident , head injury or raised intracranial pressure
5-Radiotherapy
6-Liver diseases and other causes of hypoproteinemia
7-Drug induced
8-Poisons
9-Mediastinal Tumors (producing venous or lymphatic obstruction)
10-ARDS
11-High altitude

27. -N.B. :
Unilateral pulmonary edema :
a) Pulmonary edema on the same side as a pre-
existing abnormality :
1-Prolonged lateral decubitus position
2-Unilateral aspiration
3-Pulmonary contusion
4-Rapid thoracocentesis of air or fluid
5-Bronchial obstruction
6-Systemic artery to pulmonary artery shunts

28. b) Pulmonary edema on the opposite side to a
pre-existing abnormality :
1-Congenital absence or hypoplasia of a
pulmonary artery
2-McLeod syndrome
3-Thromboembolism
4-Unilateral emphysema
5-Lobectomy
6-Pleural disease

29. 2-Radiographic Features :
-Cardiac size / cardio-thoracic ratio (LT sided
cardiac ++) : useful for assessing for an
underlying cardiogenic cause or association
-Bat wing pulmonary opacities (centrally located
lesion) , i.e. enlarged hazy hilar shadows
-Distended upper lobe vessels
-Septal lines , Kerley lines
-Thickened interlobar fissures
-Pleural effusions (right sided , if bilateral it will be
more at the RT side)
-Presence of peribronchial cuffing
-Patient is almost in the ICU with ECG leads
appearing in the film

35. c) Pulmonary Embolism :
1-Definition
2-Types
3-Risk Factors
4-Clinical Picture
5-Radiographic Findings

36. 1-Definition :
-Embolic occlusion of the pulmonary arterial
system
2-Types :
a) Incomplete Infarct :
-Hemorrhagic pulmonary edema without tissue
necrosis , resolution within days
b) Complete Infarct :
-Tissue necrosis , healing by scar formation

37. 3-Risk Factors :
a) Immobilization >72 hours (55% of patients with
proven PE have this risk factor)
b) Recent hip surgery , 40%
c) Cardiac disease , 30%
d) Malignancy , 20%
e) Estrogen use (prostate cancer ,
contraceptives) , 6%
f) Prior deep vein thrombosis (DVT) , 20%

38. 4-Clinical Picture :
-Chest pain , 90%
-Tachypnea (>16 breaths/min) , 90%
-Dyspnea , 85%
-Rales , 60%
-Cough , 55%

39. 5-Radiographic Findings :
a) Plain Radiography
b) CTA
c) Nuclear Medicine

40. a) Plain Radiography :
1-Fleishner sign : enlarged pulmonary artery
(20%)
2-Hampton hump : peripheral wedge of
airspace opacity and implies lung
infarction (20%)
3-Westermark's sign : regional oligaemia
(10%)
4-Pleural effusion (35%)

41. Fleishner Sign

42. Hampton Hump

43. -Westermark's Sign
-A chest x-ray showed an
elevated left
hemidiaphragm and an
area of focal oligemia
(Westermark's sign) in
the right lung (area
between white
arrowheads) with a
prominent right
descending pulmonary
artery

44. b) CTA :
1-Acute PE :
-Filling defects within the pulmonary vasculature
-Polo mint sign : when observed in the axial plane ,
the central filling defect from the thrombus is
surrounded by a thin rim of contrast appearing
like the popular sweet , the polo mint
-Expanded unopacified vessel
-Eccentric filling defect
-Peripheral wedge shaped consolidation
-Pleural effusion

49. Impacted thrombus distal to point of occlusion (arrow) that expands
vessel diameter

50. Eccentric filling defect within pulmonary artery (arrow)

51. With lung infarction

52. Saddle shaped thrombus

53. 2-Chronic PE :
-Webs or bands , intimal irregularities
-Abrupt narrowing or complete obstruction of
the pulmonary arteries
-Pouching defects which are defined as
chronic thromboemboli organized in a
concave shape that points toward the
vessel lumen

54. Band or web (arrow)

55. Multiple intimal irregularities (straight arrows). , poststenotic dilatation (arrowhead) is
shown affecting posterior segment of right upper lobe , also noted within right lower
lobe is tortuous vessel (curved arrow)

56. Organized thrombus (arrows) as cause of intimal irregularities , in
addition , poststenotic dilatation (arrowhead) is shown affecting
posterior segmental artery , again shown within right lower lobe is
tortuous vessel (curved arrow)

57. Pouch defect of anterior basal segment of right lower lobe (arrow) ,
contracted artery (arrowheads) is smaller than adjacent bronchus

58. c) Nuclear Medicine : V/Q scan
-Show ventilation-perfusion mismatches

59. -N.B. :
Differential Diagnosis of non-thrombotic pulmonary
emboli :
1-Septic embolism (venous catheters , tricuspid valve
endocarditis & peripheral septic thrombophlebitis)
2-Catheter embolism
3-Fat embolism
4-Venous air embolism
5-Amniotic fluid embolism
6-Tumor embolism
7-Talc embolism (in i.v. drug abusers)
8-Iodinated oil embolism (following contrast
lymphangiography)
9-Cotton embolism
10-Hydatid embolism

60. d) Venous Abnormalities :
1-Pulmonary AVM
2-Pulmonary Varices
3-Aortic Nipple
4-Pulmonary Venoocclusive Disease

61. 1-Pulmonary AVM :
a) Definition
b) Types
c) Location
d) Radiographic Features

62. a) Definition :
-Abnormal communication between
pulmonary artery and veins
-They can be multiple in 1/3 of cases

63. b) Types :
1-Congenital : 60 %
-Osler Weber Rendu Disease (Hereditary
Hemorrhagic Telangiectasia “HHT”)
2-Acquired :
-Iatrogenic
-Infection
-Tumor

64. c) Location :
-Lower lobes , 70% > middle lobe > upper
lobes

65. d) Radiographic Features :
1-Plain Radiography
2-CT

66. 1-Plain Radiography :
- A common radiographic finding is a round
or oval mass of uniform opacity
-The opacity may have sharply defined
borders with occasional lobulation
-The mass is usually 1-5 cm and linear
shadows are adjacent to the opacity ,
these are the feeding vessels

70. Multiple PAVM

71. 2-CT :
-The characteristic presentation of a PAVM on
non-contrast CT is a homogeneous well-
circumscribed non-calcified nodule up to several
centimeters in diameter or the presence of a
serpiginous mass connected with blood vessels
-Contrast injection shows enhancement of the
feeding artery , the aneurysmal part and the
draining vein on early phase sequences

72. NECT

78. 2-Pulmonary Varices :
a) Definition
b) Radiographic Features

79. a) Definition :
-Localized aneurysmal dilatation of a
pulmonary vein
-Uncommon lesions that are typically
asymptomatic and do not require
treatment , usually discovered incidentally

80. 1-Root of aorta
2-Pulmonary outflow
3-Left atrium
4-Left pulmonary vein
5-Superior vena cava
6-Descending aorta

81. b) Radiographic Features :
-Dilated vein
-Usually near left atrium

82. Dilatation of right upper pulmonary vein adjacent to left atrium

83. 3-Aortic Nipple :
-Normal variant (10% of population) caused
by the left superior intercostal vein seen
adjacent to the aortic arch
-Maximum diameter of vein : 4 mm

85. -Left superior intercotal
vein , curvilinear contrast
filled vessel along the left
lateral border of the aorta
(white arrow) that can be
traced from the left
brachiocephalic vein (red
arrow) to the region of the
accessory hemiazygous
vein (blue arrow)

86. 4-Pulmonary Venoocclusive Disease :
-Occlusion of small pulmonary veins
-The proposed initial insult in PVOD is
venous thrombosis , possibly initiated by
infection , toxic exposure or immune
complex deposition