Pleural diseases and imaging findings

1. By : Dr. JAISA RAM JRII
Radio-Imaging of Pleural Diseases

2. ANATOMY OF THE PLEURA
⚫ Pleura is a serous membrane composed
of mesothelial cells and loose
connective tissue.
⚫ Divided into : (a) Parietal pleura
(b) Visceral pleura
⚫ Parietal pleura is
further divided into :
a) Costal;
b) Diaphragmatic;
c) Mediastinal, &
d) Cervical

4. H/O TESTICULAR Ca.
now presented with chest discomfort and cough

5. Pleural Mets

6. Differential Diagnosis (pleural based mass)
1. Pleural tumours
2. Metastatic pleural disease
3. Loculated fluid
4. Mass related to chest wall or ribs
5. Mass related to intercostal nerve

7. PLEURAL DISEASES
 Pleural effusion
 Pneumothorax
 Hemothorax
 Empyema
 Chylothorax
 Pleural thickening
 Pleural calcification
 Tumours of the pleura

8. PLEURAL EFFUSION
• Excess fluid in pleural space.
• A number of different types of fluid may
accumulate in pleural space :
i. Transudate
ii. Exudate
iii. Blood
iv. Chyle
v. Pus
• All types of pleural effusion are radiographically
identical.

9.  RIGHT-SIDED EFFUSION
Typically associated with ascites, heart failure and liver
abscess.
 LEFT-SIDED EFFUSION
Pancreatitis, pericarditis, oesophageal rupture and aortic
dissection.
 OTHER CAUSES
• Tuberculosis, parapneumonic, pulmonary embolism,
malignancy, fungal infection, hydated disease,
atelectasis, etc.

12.  FREE PLEURAL FLUID
⚫ CP angles become blunted (>50ml )
⚫ Following this the classical signs develop – homogenous
opacification of lower chest with obliteration of CP angle and
hemidiaphragm.
⚫ Superior margin of opacity is concave to the lung and is
higher laterally than medially . aka meniscus sign (>200ml)
⚫ Massive effusions cause dense opacification of hemithorax
with contralateral mediastinal shift - white out lung ( 4-5 L)

13. ⚫Pleural effusion can present on imaging in following
form—1. lamellar pleural effusion
2. encysted pleural effusion
3. subpulmonary pleural effusion.

14.  In the supine patient, pleural fluid layers out in
posterior part of pleural space - hazy opacity affecting
the whole or the lower part of the hemithorax, with
preserved vascular opacities in the overlying lung (at
approx. 200ml)
 Additional signs include haziness of the diaphragmatic
margin, blunting of CP angle, thickening of minor
fissure.
 In case of doubt lateral decubitus CXR or lung USG
should be done.

15. PNEUMOTHORAX
⚫Presence of air in pleural cavity.
⚫Air enters through a defect in either the parietal or
visceral pleura. Such defects are the result of :
- Primary spontaneous pneumothorax.
- Lung pathology :secondary spontaneous
pneumothorax
- Trauma/iatrogenic: blunt trauma, aspiration pleural
effusion.
⚫If pleural adhesions are present the pneumothorax may
be localized , otherwise it may be generalized

16. ⚫If air can move freely in and out of pleural space
during respiration – open pneumothorax
⚫If no movement of air occurs – closed
pneumothorax
⚫If air enters the pleural space on inspiration, but
does not leave on expiration – valvular
pneumothorax.As intrapleural pressure increases
tension pneumothorax develops

17. Primary spontaneous pneumothorax
⚫Pneumothorax occuring without an obvious
precipitating event is spontaneous, and if the patient has
essentially normal lungs , it is in addition primary.
⚫Predominantly in young adults
⚫M:F=6:1
⚫Nearly always caused by the rupture of an apical pleural
bleb

18. Secondary spontaneous
pneumothorax
⚫A large number of conditions predispose to
pneumothorax.
• Diagnosis is made with the chest radiograph which also
detects complications and predisposing conditions and
helps in management
• Ex. COPD , Cavitating pneumonia (mcc-streptococcus
pneumonia) , pleural mets.

19.  TYPICAL SIGNS:
• Seen on erect radiographs –pleural air rises to the
lung apex. visceral pleural line at the apex becomes
separated from the chest wall by a transradiant zone
devoid of vessels
• In indeterminate circumstances ( repeat chest
radiograph, an expiratory radiograph or one taken with the patient
decubitus)
• CT is helpful in distinguishing between bullae and
pneumothorax

20. ⚫ATYPICAL SIGNS :
⚫Arise when patient is SUPINE or the pleural space is
partly obliterated
i. Ipsilateral hyperlucency
generalized or hypochondrial.
ii. Deep sulcus sign
iii. Double Diaphragm Sign

21. iv.Increased sharpness of Cardiac borders, diaphragm, mediastinum
v. Deep and well defined anterior cardiophrenic sulcus ( may be earliest
sign of small pneumothorax)
vi. Ipsilateral diaphragm depression.

22.  In case of any doubt (lateral decubitus view)
 Pneumothorax may be loculated , and must be differentiated from other
localized transradiencies (cysts , bullae, pneumatocoeles,
pneumomediastinum and local emphysema)
 Can be differentiated by CT.

23. TENSION PNEUMOTHORAX
⚫Life threatening complication ! ( IPP – Positive)
⚫Diagnosis is usually made clinically.
⚫Chest radiograph shows contralateral mediastinal shift
and ipsilateral diaphragm depression.

24. Empyema
1 Definition :
-Infected purulent and often loculated pleural effusion and
is a cause of a large unilateral pleural collection
2 Causes :
a) Postinfection (parapneumonic) , 60%
b) Postsurgical , 20%
c) Posttraumatic , 20%

25. a) Plain Radiography :
-Can resemble a pleural effusion and can mimic
a peripheral pulmonary abscess
-Form an obtuse angle with the chest wall
-The lenticular shape (bi-convex) is also
suggestive of the diagnosis

26. CXR shows pleural- based
opacity (arrow) with tapering
obtuse margins in left
hemithorax

27. CECT shows loculated
collection (arrowhead) with
peripherally enhancing thick
walls (Split pleura Sign)

28. Chylothorax
1-Definition :
-Presence of chylous fluid in pleural space often as
a result of obstruction or disruption to thoracic
duct.
2-Causes :
Tumor , 55% (especially lymphoma)
Trauma , 25%
Idiopathic , 15%

29. 3-Radiographic Features :
Plain Radiography :
-Increased density of hemithorax with ipsilateral pleural effusion
(most common on the left). Less frequently bilateral . On CT Scan
it appear as fluid collection of water density.

30. PLEURAL THICKENING
⚫Usually represents the organized end stage of various
active processes
⚫When generalized and gross, it is termed as
FIBROTHORAX and may cause significant ventilatory
impairment.
⚫Radiologically defined as smooth uninterrupted pleural
density that extends over at least one-quarter of the
chest wall.
⚫Most common site - CP angle ,apex of lung.

31. According to etiology it may be classified as:
1 ) Benign pleural thickening ( following recurrent inflammation,
pneumothorax, pleural empyema, talc pleurodesis, delayed complication
of a hemothorax, collagen VD like RA, Occupational LD )
2 ) Malignant pleural thickening
Primary malignant pleural disease
mesothelioma
primary pleural lymphoma
Pleural metastases
​ Secondary pleural lymphoma

32. ⚫ Pleural thickening may be focal or diffuse.
⚫ Diffuse pleural thickening : thickening of pleura (more than 5 mm) with
combined area of involvement more than 25% of chest wall if bilateral
and 50% involvement if unilateral.
⚫ Benign pleural thickening : greater than 5 cm in width, 8 cms in
craniocaudal extent, and 3 mm in thickness.
⚫ Malignant pleural disease features :
 Pleural thickening greater than 1 cm (specificity 94%)
 Circumferential pleural thickening: evidence of crossing the mediastinal
surface (specificity 100%)
 Nodular pleural thickening
 Mediastinal pleural thickening
 Cause mesothelioma ,metastatic pleural disease.

34. PLEURAL CALCIFICATION
⚫Most commonly seen following asbestos-exposure,
empyema (usually tuberculous), radiation therapy,
haemothorax.
⚫Asbestos related calcifications occur as more
discrete collections within plaques and is usually
bilateral with sparing of CP angles
⚫The most sensitive method for demonstrating a pleural
plaque is HRCT, and USG can be helpful in differentiating
a plaque from loculated fluid.
⚫D/D – Talc pleurodesis.

36. SOLITARY FIBROUS TUMOR OF PLEURA (SFTP)
⚫ Also known as localized fibrous tumor or localized pleural mesothelioma.
⚫ 45- 60 yrs
⚫ Most of the tumors are benign; 20 % cases – malignant.
⚫ Arises from visceral pleural in 80 %
⚫ Associations of SFTP are clubbing, hypertrophic osteoarthropathy and
hypoglycemia.

37. Benign pleural fibroma

38. Features of malignant fibrous tumor include : presence of calcification,
effusion, atelectasis, mediastinal shift , and chest wall invasion.

39. MALIGNANT MESOTHELIOMA
⚫ Highly malignant and locally aggressive tumor
⚫ 6th or 7th decade of life
⚫ Associated with asbestos exposure, with an average latency of 35-40
years for its development.
⚫ Other predisposing factors ( TB, Radiation therapy, chronic empyema)

40. 1. Diffuse nodular pleural thickening
2. Pleural plaque ( latent period is 20years , typically
involve 6-9th ribs and themselves are non-malignant)
3. Pleural effusion
4. Calcification(involving diaphragmatic pleura)
On Imaging

41. ⚫ PLEURAL PLAQUES CAN BE CLASSIFI ED
ACCORDING TO THEIR CT APPEARANCE:
⚫ 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.

42. Nodular thickening of pleura involving right hemithorax with small
pleural collections (arrows)

44. ⚫ D/D:
⚫ Differentiation from metastatic carcinoma is difficult –
 Features in favour of mesothelioma include: unilateral
involvement and volume loss of affected hemithorax.
⚫ Imaging criteria for unresectability include:
 Encasement of diaphragm
 Involvement of extrapleural fat, ribs or other mediastinal
structures

45. LYMPHOMA
⚫ Both hodgkin’s and non
hodgkins lymphoma
can involve the pleura.
⚫ IMAGING :
⚫ Pleural effusion
⚫ Pleural nodules
⚫ Focal or diffuse pleural
thickening
(circumferential pl.
thickening is less
common).
⚫ Homogeneous contrast
enhancement
⚫ Associated with
mediastinal and hilar
lymphadenopathy

47. PLEURAL METASTASES
⚫ Adenocarcinomas are known to cause pleural metastasis
than any other histological types of cancers.
⚫ Common primary sites are from : lung, lymphoma, and
ovary, invasive thymoma
⚫ Pleural effusion is the most common finding on imaging .
⚫ PET shows increased 18F- FDG uptake in malignant pl.
thickening and effusion.

48. INVASIVE
THYMOMA
METASTASIS FROM
ADENOCARCINOMA
METS FROM
RCC

49. ASKIN TUMOR
⚫ Aggressive malignant tumor of primitive neuroectodermal
origin.
⚫ Mostly arise from the soft tissues of the chest wall or lung
periphery.
⚫ Children & adolescents.
⚫ IMAGING :
⚫ U/L involvement usually seen
⚫ Nodular pleural thickening
⚫ Infiltration into the chest wall, mediastinum and
sympathetic chain is pathognomic.
⚫ Pleural effusion and rib destruction may or may not be
seen.

51. RARE PATHOLOGIES OF PLEURA
1) PLEURAL LIPOMA (often an incidental finding; one of the most
common benign tumors of the pleura; fat density tissue with no
contrast enhancement)
2) PLEURAL SPLENOSIS (occurs following trauma on left side)
3) MESOTHELIAL CYSTS
4) EPITHELIOID HEMANGIOENDOTHELIOMA
5) CASTLEMAN DISEASE
6) SARCOMAS
7) MALIGNANTG FIBROUS HISTIOCYTOMA
8) LEUKEMIC INFILTRATION
9) EXTRASKELETAL OSTEOSARCOMA (RARE: but should be
considered in the differential diagnosis for a rapidly growing calcified
pleural mass in an elderly)

52. Pleural lipoma. Smooth, pleurally based fat-density
mass in the left anterior hemithorax

53. PLEURAL PSEUDOTUMOR
⚫ Is a fluid collection within the lung fissure.
⚫ Most common site : MINOR FISSURE
⚫ Common causes include :
 Congestive heart failure
 Cirrhosis
 Renal insufficiency
⚫ On chest radiographs:
⚫ Classical lenticular or biconvex opacity is seen in the
fissure.
⚫ Usually resolves after therapy with diuretic agents

54. THANK YOU !!