Approach in Pleural pathologies

1. Approach in Pleural
Pathologies
Dr Subash Pathak
First Year Resident
Radiodiagnosis, NAMS

2. Outline of presentation
• Anatomy of pleura
• Common imaging modalities used to assess the pleural pathologies.
• Common pleural diseases.
• Approach in assessment of tumorlike conditions of pleura.

3. Anatomy
• Serous membrane
• Visceral and Parietal pleura
• Visceral pleura covers the lung
• Parietal pleura lines the thoracic cavity
and mediastinum
• Named according to site: Costal,
mediastinal, diaphragmatic, apical
• Pleural Space: Potential space between
visceral and parietal pleura.
• 8 ml of acellular clear fluid in each
space.

4. • Visceral and parietal pleura are
continuous with each other anterior
and posterior to lung roots.
• Below the hilum, the two layers form
loose fold extending inferiorly:
Pulmonary ligament.
• The visceral pleura extends into the
interlobar and accessory fissure.
• At rest, visceral pleura extends
deeper into the costophrenic and
costomediastinal recesses than the
lungs and visceral pleura.

5. • The pleura extends more caudally than the accompanying lung, to the
level of the T12 vertebra.
• The diaphragm is often involved in malignant pleural disease and
extends more inferiorly still, with the right crus arising from the
anterolateral surfaces of the bodies and intervertebral discs of the
upper three lumbar vertebrae.

6. S.no. Visceral Pleura and Lung Parietal pleura
1 Anterior Sixth costal
cartilage
Seventh costal
cartilage
2 Midaxillary line Eigth rib Tenth rib
3 Posterior T10 T12

7. Blood Supply
• Arterial supply:
• Parietal pleura :Internal thoracic, intercostal and phrenic arteries;
• Visceral pleura : Bronchial and pulmonary arteries
• Venous drainage: Bronchial and pulmonary veins

8. Lymphatics
• Visceral Pleura: Follows that of lung
• Parietal Pleura:
1. Anterior pleura - internal mammary nodes,
2. Posterior pleura - extrapleural lymph nodes, adjacent to the heads
of the ribs.
3. The diaphragmatic lymphatics drain to internal mammary, anterior
diaphragmatic, para-aortic and posterior mediastinal nodes.
• There is also free communication with lymphatics on the abdominal
surface of the diaphragm, and coeliac axis or gastrohepatic nodes
may be involved in pleural disease processes.

9. Chest Radiography
• The imaging modality of choice for the initial investigation of pleural
disease.
• PA film initially; if any abnormalities then further assessment can be
done using lateral and decubitus films.
• In normal X-ray, normal pleura is seen as fissures and junctional lines.

10. Ultrasonography
• Intercostal space as sonographic window.
• 3.5-5.0 MHz sector transducer with small footprint.
• Higher frequency transducer though has higher spatial resolution,
lacks sufficient penetration.
• Pleural surface: Reflective band differentiated from relatively
hypoechoic tissues of the chest wall.
• Predominantly homogenous zone of reverberation echoes distally.

11. Computed tomography
• Further characterize pleural abnormalities seen in CXR and ultrasound.
• Ideally performed before any effusion is drained.
• Scanned from the thoracic inlet to L3 level to scan entire diaphragm and
pleura.
• IV contrast given if effusion is present or suspicious pleural thickening.
• Delay of 60 sec for maximum pleural enhancement.
• Intercostal stripe: extrapleural fat, endothoracic fascia, innermost
intercostal muscle.
• Visceral and parietal pleura and endothoracic fascia not visualized passing
internal to the ribs on HRCT unless pathologically thickened.

12. Normal pleural and chest wall
anatomy. On this unenhanced axial
CT image, the intercostal stripe
comprises the visceral and parietal
pleura, extrapleural fat,
endothoracic fascia and innermost
intercostal muscle. The intercostal
vessels (black arrowhead), internal
intercostal muscle (white
arrowhead) and external intercostal
muscle (black arrow) can be seen
lateral to the innermost intercostal
muscle (solid white arrow).

13. Magnetic Resonance Imaging
• Cardiac gating and respiratory compensation required.
• Normal pleural surfaces, fissures and junctional lines not seen on
MRI.
• Useful for the assessment of tumor extension through the pleura and
detection of pleural malignancy.

14. Diseases of the pleura

15. Pleural Effusion
• Radiological appearances of pleural fluid
• Chest Radiograph:
• Fluid cast the density of water or soft tissue
• If no adhesion, the position and morphology of the shadow depends
on: Amount of fluid, the state of underlying lung and the position of
the patient.
• Costophrenic angle recess – most dependent recess of pleura
• 100-200 ml of fluid fills up the recess, then only becomes visible in
the frontal radiographs.

16. • Smaller effusions seen in lateral radiographs; even smaller (few
millimeters) in decubitus views with horizontal beam, USG or CT.
• With increasing fluid accumulation, the radiographic findings are:
1. Homogenous opacity spreading upwards, obscuring the lung base
2. Fairly well defined
3. Concave upwards
4. Higher laterally than medially
5. Obscures the diaphragmatic shadow

17. Chest Radiography

18. Small bilateral pleural effusions. Man aged 34, renal transplant patient with cytomegalovirus
pneumonia. The effusions probably relate to renal
failure rather than the pneumonia. (A) PA film shows subtle filling in of both costophrenic
angles. (B, C) Horizontal-beam right and left lateral decubitus
films show obvious free pleural effusions collecting along the dependent lateral costal
margins (arrowheads

19. Massive effusion and Mediastinal shift
• Complete radiopacity of hemithorax
• Underlying lung retracts towards the hilum
• Space-occupying effect of the effusion pushes the mediastinum to
opposite side.
• Large effusion without displacement of mediastinum – complete lung
collapse.
• Moderate effusion with ipsilateral mediastinal shift due to lung
collapse – usually due to carcinoma bronchus.

20. Large pleural effusion. Man of 28 with well-differentiated lymphocytic
lymphoma. PA fil m shows a large left pleural effusion extending
over apex of lung and pushing the mediastinum to the right. A small right
pleural effusion is also present, and right paratracheal shadowing represents
lymphadenopathy.

21. Atypical distribution of pleural fluid
• Lamellar effusions
• Subpulmonary pleural effusions
• Collection in azygo-oesophageal recess

22. • Lamellar effusions: Shallow collections between the lung surface and the
visceral pleura, sometimes spares the CP angle.
• In fact represents interstitial pleural fluid.
• Subpulmonary pleural effusion: Large fluid accumulation between
diaphragm and undersurface of lung.
• Mimics diaphragm elevation.
• Features:
• Diaphragm contour is altered, apex more lateral than usual.
• Blunting of CP angle or pleural effusion.
• Left side: increased distance between gastric air bubble and lung base.
• Fluid will move with postural change (lateral decubitus or supine films).

23. Lamellar pleural effusions,
postcardiac surgery. Erect AP film
shows fluid filling both
costophrenic angles and extending
up the lateral
chest wall (arrowheads).

24. Fifteen-year-old male with adriamycin-induced cardiomyopathy and recently increasing shortness of breath. (A)
Erect PA film shows a large heart and apparent elevation of the right hemidiaphragm due to a large subpulmonic
effusion. (B) Lateral film shows fluid tracking up the posterior chest wall and blunting the posterior costophrenic
recess. (C) Supine chest radiograph obtained shortly afterwards showing redistribution of pleural fluid. The
appearances are now typical of a large supine pleural effusion with increased density of the right hemithorax.
(D) Ultrasound of the right lung base reveals a large anechoic space consistent with an uncomplicated Pl Eff

25. Azygo-oesophageal recess
collection: Large right pleural
effusion may collect in the recess
and mimic a retrocardiac mass.

26. Loculated fluid
• Obliteration of pleural space due to fusion of visceral and parietal
pleura due to pleural disease.
• Distinguished from free pleural fluid by gravitational methods.
• Lenticular shape (more width, less height).
• Often associated pleural effusion or fissural effusion.
• May loculate in interlobar fissure.
• Appearance depends on the fissure involved and amount of fluid.

27. • Horizontal fissure: round, oval or lenticular shape in both frontal and
lateral projections with well demarcated edges.
• Oblique fissure: poorly defined in frontal view, lateral view shows
lenticular opacity.
• Pseudo/vanishing tumor
• D/D: 1.Extrapleural opacities 2. Parenchymal lung disease 3.
Mediastinal mass

28. Fig. 3.12 Loculated interlobar pleural effusions in a woman of 60 after replacement of the aortic root. (A)
Nineteen days postoperatively a right mid-zone opacity appears (arrows), with a sharp lower margin and an
indistinct upper margin. The right costophrenic angle has also filled in. (B) Lateral projection demonstrates
typical lenticular configuration of fluid loculated in the oblique fissure (arrows). (C) Seven days later a second
round opacity has appeared below the first. This opacity is well circumscribed. (D) Lateral projection confirms
that this is fluid loculated in the horizontal fissure (arrows).

29. Empyema
• Infected pleural effusion.
• Plain radiography: Suspected if “fluid level” seen in a pleural effusion.
• Best diagnosed by CT/Ultrasound.
• CT:
• lenticular shape with underlying lung compression
• Gas may or may not be present
• Both layers of pleura thickened; may prevent re-expansion of lung causing
respiratory failure.
• Development of pleural rind if chronic; catheter drainage is not possible.

30. CT scan through the lower thorax in a
patient with a right basal empyema
collection. There is associated pleural
thickening and
compression of the adjacent lung
parenchyma.
PA chest radiograph showing multiple fluid
levels in a patient with a heavily loculated
empyema complicating
attempted pleurodesis.

31. (A) Large left pleural effusion due to carcinoma of bronchus. There is a large echo-free effusion above the left
hemidiaphragm (arrowheads) and spleen(s). (B) Empyema following right lower lobectomy. A poorly echogenic
collection is seen above the diaphragm (arrowheads). (C) Loculated pleural effusion due to tuberculosis.
Ultrasound demonstrates thickening of the parietal pleura (P) and multiseptated fluid collection above the
diaphragm.

32. Empyema vs Parenchymal Abscess

33. Empyema vs Parenchymal Abscess

34. CT in pleural effusion
• Complementary to chest x-ray and USG.
• Added benefits:
1. More sensitive for small pleural effusion.
2. Better defines the extent of pleural abnormalities.
3. Identifies associated lung abnormalities if present.
4. Differentiating loculated effusion from other d/d.
• Pleural fluid shows lower attenuation than pleural thickening, or
consolidated or fibrotic lung.
• Hemothorax may show increased attenuation.
• Pleural fluid associated with pleural thickening likely to be exudate.

35. Differentiating ascites and pleural effusion
• Displaced crus sign
pleural fluid collect posterior to crus displacing crus anteriorly while
ascites collect anterior to crus displacing it posteriorly.
Displaced crus sign: The right
pleural effusion
collects posterior to the right
crus of the diaphragm (arrows)
and displaces
it anteriorly.

36. Diaphragm sign: The pleural fluid
(p) is over the outer
surface of the dome of the
diaphragm, whereas the ascitic
fluid (a) is within
the dome
• Diaphragm Sign:
• Any fluid that is on the exterior of the dome of the diaphragm is in
the pleura, whereas any that is within the dome is ascites.
• Extension of displaced crus sign

37. The interface between
the liver and ascites
(arrows) is sharper than
between liver and
pleural fluid
• Interface Sign:
• Interface between the liver or spleen and pleural fluid is less sharp
than that between liver or spleen and ascites.

38. • Bare Area Sign:
• The peritoneal coronary ligament prevents the extension of the ascitic
fluid over the entire posterior surface of the liver whereas in a free
pleural space, pleural fluid may extend over the entire posterior
costophrenic recess behind the liver.

39. Pleural Calcification
• Unilateral pleural calcification:
1. Previous Hemothorax,
2. empyema
3. pleurisy
• Bilateral pleural calcification:
1. Asbestos exposure (in parietal pleura, more delicate)
2. Other pneumoconiosis
3. Occ after bilateral pleural effusion

40. • Calcification associated with previous pleurisy, empyema or
hemothorax:
• Occurs in the visceral pleura.
• Associated pleural thickening always present.
• Continuous sheet or discrete.
• Dense, coarse, irregular shadows, sharply demarcated
laterally.
• Can mimic as pulmonary infiltrate in PA views.
• Pleural origin can be confirmed with lateral view or use of
Fluoroscopy.

41. Pleural Calcifications

42. Pneumothorax
• Presence of air in the pleural cavity.
• Types:
• Spontaneous: a) Primary b) Secondary
• Traumatic
• Artificial
• Secondary Pneumothorax: Due to underlying lung pathologies.
• Primary spontaneous pneumothorax: Young men, d/t rupture of a
congenital pleural bleb.
• In the lung apices, usually bilateral.

44. Radiological appearances:
• Chest Radiograph:
• Small pneumothorax: Erect
film collects at lung apices.
• Apex retracts towards the
hilum.
• Radiolucent pleural space
without bronchovascular
markings.
• Thin sharp white visceral
pleural line.

45. • Expiratory film can help better visualize the closed pneumothorax.
• Lateral decubitus film with affected side up – pleural air along the
lateral chest wall.
• Large Pneumothorax: Complete retraction of lung with mediastinal
shift to normal side, increases on expiration.
• Tension Pneumothorax:
• Ipsilateral lung is sqashed against the mediastinum or herniate across
the midline.
• Ipsilateral hemidiaphragm is depressed.
• Fluoroscopy: Mediastinal shift to contralateral side is greatest in
inspiration.

46. Pneumothorax

48. USG in Pneumothorax:
• Lung Sliding Sign: To- and –fro
movement of the visceral and
parietal pleura on respiration at the
echogenic interface between chest
wall soft tissue and aerated lung.
• Loss of lung sliding.
• Loss of normal reverberation echoes
distal to pleural reflective echogenic
band.

49. Pleural Tumors

50. Fibrous tumor of pleura
• Solitary (or localized) fibrous tumor of the pleura (SFTP) is a rare
neoplasm of mesenchymal origin.
• Benign 80% or Malignant 20%.
• Often asymptomatic, incidental finding on chest x-ray.
• Hypertropc pulmonary osteoarthropathy or hypoglycemia.

51. Radiography
• Smooth or lobulated.
• 40% pedunculated, mobile.
• Adjacent to chest wall, diaphragm, mediastinum or a fissure.
• A homogeneous, well-circumscribed, noninvasive mass of soft tissue
attenuation.
• Large tumors show areas of differential enhancement and areas of
low attenuation due to necrosis.

52. FIG :PA view of the chest in a patient with fibrous tumors of the pleura
showing large, lobulated left chest masses. B, Axial CT image showing a
mass abutting the left posterior pleura and a partially imaged fissural
mass

53. Subpleural lipomas
• Well defined round masses.
• May change shape with respiration, being soft tumors.
• Large one may erode adjacent ribs.
• CT: Fat attenuating lesion.
• MRI: T1- High signal, T2- intermediate signal, suppression on fat
saturated images.
• Heterogenous appearance and attenuation values > -50 HU within the
mass - ? Liposarcoma

54. Pleural lipoma. (A) Chest radiograph of an asymptomatic patient shows a
well-circumscribed, round capacity (arrowheads) projected over the heart. (B) CT
scan shows it to be a pleural mass of entirely fat density. (C) Parasagittal reconstruction
of the multislice CT scan shows the mass lying above the diaphragm within the
posterior costophrenic recess

55. Pleural Metastases
• Metastatic disease is more common than primary pleural malignancy.
• Primary Sites
• Lung ,breast and Ovarian
• Gastric carcinomas, and lymphoma.
• Renal cell carcinoma and melanoma
• May present as solitary implants or circumferential rind.

56. Malignant Pleural Mesothelioma
• Mesothelioma is an uncommon neoplasm; m/c from pleura.
• Rarely from pericardium or peritoneum.
• Usually due to prolonged exposure to asbestos dust, crocidolite.
• Exposure to mesothelioma development: 20-40 years.

57. Imaging Findings:
• Nodular pleural thickening around all or part of the lung.
• Unilateral Hemorrhagic pleural effusion, often obscuring the mass.
• Mediastinum is central despite large effusion: Balance due to volume
loss of the underlying lung (ventillatory restriction or bronchial
stenosis by tumor at hilum).
• Adjacent rib destruction (pleural mass with destruction of underlying
rib is usual finding in metastatic bone tumor or primary bone tumor).

58. Pleural thickening in a 51-year-old man with MPM.
Axial contrast-enhanced CT scan shows
circumferential and nodular left sided
pleural thickening (arrows). The tumor
encases the contracted left hemithorax, having a
rindlike appearance
• Pleural thickening considered
malignant when:
1. Nodular thickening.
2. Thickening extending into fissures
or over the mediastinal surface.
3. Lung encasement.
4. Loss of volume of the ipsilateral
lung.

59. • MRI in Malignant Mesothelioma
• Assessment of involvement of mediastinum and chest wall.
• SI from a mesothelioma:
• T1/T2 Slightly higher than muscle.
• Contrast: Enhances.
• Better prediction of overall resectability.

60. Figure : MR imaging evaluation of MPM in a 63-year-old man. (a, b) Coronal (a) and contrast enhanced
fat-saturated (b) T1-weighted MR images show a large, enhancing right apical mass (M) with invasion
of the chest wall.

61. MPM : Locally Invasive
• Invasion to the chest wall
• Invasion to the mediastinum
• Invasion to the diaphragm
• MPM can extend into the chest wall via needle biopsy tracks, surgical
scars, and chest tube tracts

62. Invasion to the Chest wall
• Obliteration of extrapleural fat planes
• Invasion of intercostal muscles
• Displacement of ribs, or bone destruction
However, irregularity of the interface between the chest wall and the
tumor is not a reliable predictor of chest wall invasion.

63. Chest wall invasion

64. Mediastinal Invasion
• Direct extension of the tumor into
vascular structures and mediastinal
organs (Heart, oesophagus, and
Trachea).
• Obliteration of surrounding fat
planes/ soft-tissue mass that
surrounds >50% of the
circumference of a vascular
structure – Strong evidence of
invasion.

65. Pulmonary Metastasis: In a 68 year old man with MPM. Axial HRCT shows
extensive septal thickening and perilymphatic nodules (arrows), findings consistent with
lymphangitic tumor spread.

66. Nodal Metastasis
• Metastasis to the hilar and mediastinal lymph nodes is present at
autopsy in approximately 40%–45% of patients with MPM.
• However enlarged nodes alone do not prove nodal involvement.

67. Tumorlike conditions of pleura
• Any non-neoplastic condition of the pleura itself, or within the pleural
space, that resemble a tumor.
• Though rare, need to be distinguished from extrapleural, pleural and
peripheral lung (subpleural) tumors.
• Need to be differentiated from more common pleural tumors like
metastasis, malignant mesothelioma, and solitary fibrous tumor of
pleura.

68. • First step: Deciding the lesion is either pulmonary or extrapulmonary.
• Pulmonary lesions:
1. Centered in lung tissue
2. Forms acute angle with the chest wall
3. Seen to engulf pulmonary vessels on cross-sectional imaging.
• Extrapulmonary lesions:
1. Incomplete border sign
2. Obtuse angle with chest wall
3. Displacement of pulmonary vessels on cross-sectional imaging.

69. First step in diagnosis: deciding
whether the lesion is pulmonary or
extrapulmonary. (a) Axial
contrast material–enhanced
computed tomographic
(CT) image of a patient shows a
peripheral large cell carcinoma of the
lung. (b) Axial CT image (same patient
as in a) shows two findings of a
pulmonary lesion:
The mass is centered within lung
tissue (blue circle) and makes an
acute angle (yellow angle) with the
chest wall. (c) Posteroanterior chest
radiograph of a different patient from
the one in a and b shows a solitary
fibrous tumor of the pleura.
(d) Posteroanterior chest radiograph
(same patient as in c)
shows an extrapulmonary lesion. The
incomplete border sign
(yellow hemicircle) is observed when
only a portion of the margin of the
mass is depicted.

70. • Next Step: If the extrapulmonary lesion is pleural!!
• Pleural lesion:
1. Centered in the pleural space.
2. Usually will not involve the chest wall.
3. May cause outward displacement extrapleural fat.
• Extrapleural lesion:
1. Centered within the extrapleural compartment e.g. ribs
2. May destroy bone
3. May cause inward displacement of extrapleural fat.

71. • Third step: Deciding whether the lesion is tumor
or tumor like condition.
• Needs to rule out malignant pleural tumor.
• Malignant pleural tumor:
1. Nodular and asymmetric pleural thickening
>1cm
2. May involve both mediastinal or lateral
pleural compartments.
• Common malignant pleural tumors:
1. Metastasis m/c from lung, breast and GI
primaries/ drop metastasis from thymoma or
thymic carcinoma
2. Mesothiloma m/c primary pleural tumor

72. Tumorlike conditions of pleura
• After exclusion of pleural tumors, the lesion likely represents
tumorlike condtion.
• However, imaging appearances overlap with pleural tumors.

74. Pleural Plaque
• Arise in parietal pleura; rarely visceral pleura in the lung fissures.
• Sites: Diaphragmatic dome, undersurface of lower posterolateral ribs.
• Related to Asbestos exposure, predictor of future mesothelioma or
bronchogenic Ca.
• Absent from the CP angles and over lung apices.
• Calcification: x-ray – 10-15% and CT 15-20%
• X-ray: Geographic or holly-leaf shaped lesions.
• CT: more sensitive and specific.
• Discrete, raised parietal pleural thickening in characterstic locations.

75. Classification of pleural plaques
• Minimal pleural plaques: less than 1 mm thick, 1 to 3 cm long, and
few in number
• Moderate pleural plaques: 1 to 3 mm thick, 2 to 5 cm long, and
multiple
• Severe pleural plaques: thicker than 3 mm, clearly indenting adjacent
lung, up to 8 cm in craniocaudal dimension, and extensive in width

76. Drawing shows the typical
distribution of the pleural
plaques associated with
asbestos exposure.

77. Asbestos-related pleural plaques involving a
fissure and the posterior pleural surface in a
patient. (a) Axial CT image obtained with lung
window shows a discrete oval lesion (black arrow)
in the left major fissure. Note more typical
locations of pleural plaques (white arrows)
in the lateral and posterior pleural space. (b) Axial
CT image obtained with soft-tissue window (same
level as in a) shows that both the fissural and
posterior pleural plaques (arrows) are partially
calcified. (c) Coronal CT image shows noncalcified
plaque (white arrow) in the minor fissure. A
helpful clue to diagnosing a fissural plaque is the
depiction of bilateral calcified and noncalcified
plaques (black arrows) in characteristic locations
along the diaphragm and the chest wall.

78. • Autotransplantation of splenic tisuue into the pleural space after
trauma.
• Combined diaphragmatic and splenic injuries, more after penetrating
injuries.
• Usually asymptomatic, incidental finding; rarely chest pain or
hemoptysis.
• Diagnosis:
1. Evidence of remote splenic trauma ie, splenectomy or splenules in
left upper quadrant.
2. Solitary or multiple left pulmonary nodules
Thoracic Splenosis

79. 6. Drawing of thoracic splenosis
shows an absent spleen, a diaphragmatic
tear, and nodules of splenic tissue in the lower
left pleural space and in the splenic bed.
(7) Thoracic splenosis in a 40-year-old man with a
remote
history of a gunshot wound. (a) Axial CT image
shows multiple nodules (arrow) in the left
lower pleural space. (b) Radionuclide image
obtained with heat-damaged red blood cells
tagged with technetium 99m (99mTc) helps confirm
that the pleural nodules (arrows) represent
splenosis. Note the radiotracer accumulation
below the left hemidiaphragm, which indicates
abdominal splenosis, a finding that often accompanies
thoracic splenosis.

80. Catamenial Pneumothorax
• Recurrent pneumothorax in conjunction with menstrual cycle as a result of
thoracic endometriosis.
• Endometriosis implantation in the right pleural space and right hemidiaphragm.
• Cyclical necrosis of endometrium causing small fenestration of the
hemidiaphragm.
• Patient presentation: Right scapular or thoracic pain occurring between 24 hrs
before to 72 hrs after menstruation.
• Imaging: Right sided Pneumothorax in 90% of patients.
• CT: rarely shows small pulmonary nodules representing endometrial implants.
• If doubt exists, VATS to detect characterstics nodular brown lesions or
diaphragmatic holes.

81. Catamenial pneumothorax in a 40-year old woman. (a) Posteroanterior radiograph shows a right-
sided pneumothorax (arrows). (b) Image obtained at video-assisted thoracoscopic surgery shows
round brown endometrial implants (arrows) on the right hemidiaphragm.

82. Pleural Pseudotumors
• Pleural fluid collection in the lung fissure.
• m/c in the minor fissure (56%) CASES.
• Any atelectasis or scar in one of the lobes causes traction in the
fissures leading to pulling of fluid in the fissure.
• Almost always occurs with the transudative effusion.
• Chest radiograph:
1. Shape: Biconvex/lenticular
2. Associated dependent pleural effusion
3. Resolution after treatment of cause

83. Pleural pseudotumor of the right major fissure in a 35-year-old woman. (a) Posteroanterior
radiograph shows a biconvex opacity. (b) Lateral radiograph shows an unusually round
pseudotumor in the right major fissure. (c) Coronal CT image helps confirm the location of
the fluid (arrow) within the right major fissure. Note how the fluid tapers laterally into the
fissure. (d) Posteroanterior radiograph obtained after diuretic therapy shows complete
resolution of the pseudotumor.

84. • Role of CT: needed in difficult cases when:
1. Fluid situated along the lung edges
2. Difficult to relate to the fissure
3. Unusual shape

85. Nonpleural mimic of tumor: Extrapleural
Hematoma
• m/c follows blunt trauma
• Penetrating injury/ iatrogenic injury/ Aortic rupture
• Injury to intercostal vessels or internal mammary vessels without
disruption of parietal pleura.
• Can expand rapidly causing respiratory failure/circulatory collapse.
• Venous vs Arterial:
• Arerial is larger and biconvex, need urgent treatment.
• Venous is smaller and non-convex, conservative management.

86. • Diagnosis: CT
• Extrapleural fat sign: High attenuation collection that displaces the
extrapleural fat inwards.

87. Diffuse Tumorlike conditions

88. Diffuse pleural thickening
• Common causes:
1. Empyema
2. Hemothorax
3. Connective tissue disorders
4. Asbestos exposure
• Due to inflammatory pleuritic that fuses the visceral and parietal pleura,
restrictive lung disease.
• Often undergoes calcification, ill defined, irregular, and span multiple ribs.

89. • Distinguished from pleural plaques:
1. Greater extent
2. Fading margins, unlike discrete raised margins in plaques
3. Blunting of costophrenic angle (not seen in pleural plaque)

90. Malignant Pleural thickening
• Pleural thickening greater than 1 cm (specificity 94%)
• Circumferential pleural thickening: evidence of crossing the
mediastinal surface (specificity100%)
• Nodular pleural thickening (specificity 94%)
• Mediastinal pleural thickening (specificity 88%)

91. Diffuse pleural thickening caused by remote tuberculosis with empyema in an 84-year-old woman.
Posteroanterior (a) and lateral (b) radiographs show typical diffuse calcified left pleural thickening.
Note the blunting of the left costophrenic angle and the extensive posterior pleural involvement
(between arrows in b).

92. Apical Pleural Thickening
• Bilateral and/or symmetrical
1. Elderly
2. Uncertain aetiology
3. No association with tuberculosis
• Asymmetrical and/or Unilateral
1. May have pathological significance.
2. Associated pain - ? Pathological.
3. Asymmetrical - ? Pancoast tumor, need to assess the adjacent ribs and
spine.

93. Bilateral apical pleural thickening. An
incidental finding in a 67-year-old man
with ischaemic heart disease. The apical
pleural shadowing (arrowheads) is
symmetrical, although the edge is better
seen on the left.
Common causes of apical
shadows
Pleural caps
Pleural fluid
Bullae
Pancoast tumour
Pneumothorax
Infections-tuberculosis
Soft tissue, e.g. companion
shadows, hair,
sternocleidomastoid muscle

94. Erdheim-Chester Disease
• Rare multisystem disorder
• Non-Langerhans cell histiocytosis
• Xanthomatous infiltration of organs by foamy lipid-laden histiocytes
• m/c manifestation: Skeletal – symmetric long bone sclerosis often
involving distal femoral metadiaphysis.
• Other common organs involved: CNS, Lungs, Heart, and
retroperitoneum.
• Pulmonary involvement in 14-23% of patients.

95. • Thoracic Findings:
1. Symmetric circumferential pleural thickening or effusion
2. Smooth interlobular septal thickening
3. Centrilobular nodules
4. Pericardial thickening
• Retroperitoneal involvement may accompany thoracic findings
manifesting as circumferential soft-tissue encasement of the kidneys
and aorta.
• Sharply demarcated from surrounding perirenal or periaortic fat.

96. (a) Anteroposterior knee radiograph
shows osteosclerosis (arrowheads)
involving the distal femoral metaphysis
and the proximal tibial metadiaphysis.
B) 99mTc–methylene diphosphonate
(MDP) shows increased radiotracer
deposition
Erdheim-Chester disease in a 33-year-old woman. (a) Axial
contrast-enhanced CT image of the chest shows circumferential
pleural (white arrow) and pericardial (black arrow) thickening.
Thickening extends into the major fissures. Note the interlobular
septal thickening in the middle and left lower lobes. (b) Axial
contrast-enhanced CT image of the abdomen shows the
circumferential soft-tissue thickening (arrows) around the kidneys
that is typical of Erdheim-Chester disease.

97. Diffuse Pulmonary Lymphangiomatosis
• Proliferation and dilatation of lymphatic channels in the pleura,
interlobular septa, and mediastinum.
• Congenital developmental abnormality of the lymphatic channels.
• Teenagers and young adults.
• Predominantly involves the upper lobes in lymphatic distribution.
• Imaging Findings:
1. Smooth symmetric interlobular septal and peribronchovascular
interstitial thickening.
2. Diffuse pleural thickening/ diffuse mediastinal fat infiltration
3. Pleural effusion/pericardial effusion
4. Persists despite diuretic therapy

98. Drawing of diffuse pulmonary lymphangiomatosis shows scattered areas of ground-
glass opacity, interlobular septal thickening, pleural effusions, and infiltration of
mediastinal fat with complex lymphatic channels.

99. Diffuse pulmonary lymphangiomatosis in a 24-year-old woman. (a) Axial CT image of the lungs shows smooth
interlobular septal thickening (arrow) in the right middle lobe. (b) Axial CT image obtained with soft-tissue
window at the level of the heart shows diffuse bilateral pleural and pericardial infiltration with lymphatic
elements. (c) Axial CT image of the superior mediastinum shows diffuse infiltration of the mediastinal fat with
soft tissue (arrow). Characteristically, there is little mass effect on surrounding vessels.

100. References
• Textbook of Radiology, David Sutton 7th edition.
• Anatomy for Diagnostic Imaging, Stephanie Ryan
• Imaging of pleural disease R E BENAMORE, MRCP, FRCR, 2D R
WARAKAULLE, MRCP, FRCR and 1Z C TRAILL, MRCP, FRCR Imaging, 20
(2008), 236–251
• Radiographics, Tumorlike conditions of pleura

101. THANK YOU