Pleural(Mesothelioma Radiology)

Mesothelioma Radiology

Fluid accumulation in the pleural space Mesothelioma radiology can be diagnosed on the thorax image in the lateral position and horizontal beam path from 15 ml. They are detected more reliably by computer tomography or sonography. CT also helps differentiate empyema and abscess, the detection of small wasps, and pleural tumors and their precise location. Sonographically, even small free or encapsulated effusions of calluses or masses are demarcated. Magnetic Resonance Imaging is the expression of pleural effusions and masses, as well as thoracic wall infiltration of bronchial carcinomas or mesotheliomas.
Pleural plaques and calcifications are detectable to a limited extent on postero-anterior, lateral and oblique chest X-ray. A better representation succeeds computertomographisch.

The inside of the thorax is lined by the parietal pleura. The lungs are covered by the visceral pleura. Between the two adjoining pleural leaves is a thin liquid film. The pleura cannot be visualized in the X-ray image or in the new slice imaging procedure. The visceral pleura becomes visible only when air enters between the pleural leaves, these are distanced from each other (pneumothorax) and the pleura-coated lung is tangentially imaged. However, the adjacent visceral pleural leaves of the cleft gaps are recognizable in the computed tomogram with thin layers as a compression line.

In a computed tomographic or magnetic resonance tomographic cross-section of the thoracic wall, from inside to outside, as shown:
Lung tissue - subpleural fat lamella (1-2mm thick) - Intercostal muscle intimus - rib cortical bone.
The subpleural fat lamella has diagnostic significance. It is no longer present on tumor infiltration into the thoracic wall.


1. pleural effusion
The pleural space usually contains about 5 ml of free interstitial fluid. There is a balance between production and absorption of about 10 ml daily. Increased pleural fluid is called effusion. An effusion arises through

1. increased hydrostatic pressure (e.g., in case of increased venous and capillary pressure due to cardiac stasis)
2. reduced oncotic pressure (in case of nephrotic syndrome by hypoalbuminemia)
3. increased negative pressure in the pleural space (by atelectasis)
4. increased permeability in the microcirculation area (in case of inflammation or tumor)
5. Resorption disorder (due to fibrosis or tumor)
6. Transdiaphragmalen fluid transport via lymph vessels (abscess or pancreatitis).
Clinically important is the distinction between transudate and exudate. The transudate corresponds to non-resorbed interstitial fluid. The cause is usually cardiac congestion, including, inter alia, upper Einflussstauung or nephrotic syndrome. Exudate is caused by, among other things, infections, tumors or autoimmune diseases. It has a higher protein content than a transudate. Transudate and exudate cannot be differentiated radiologically.

An empyema is a collection of pus in the pleural space (if, for example, a lung abscess breaks into the pleural space).

A hemothorax is hemorrhage into the pleural space (eg in case of rib fracture).

Chylothorax exists in lymph in the pleural space, eg. in lymph fistulas or injury to the thoracic duct. Lymph drainage is via the visceral pleura.

It is clinically important to distinguish effusion and rind. An unabsorbed effusion went blank. This results in reduced mobility and reduced ventilation of the lungs. Narrow effusions are often not distinguishable from calluses in CT.

Sign of the pleural effusion in the radiograph:
Homogeneous basal compaction in standing patient
Rounding off the chest wall (meniscus sign) At least 200 ml, sometimes more, are necessary for the development of these signs.
The cleft spaces are widened when the effusion has entered (jumped in)
In the dying patient, the effusion runs out cranially.
in the dying patient, the shading fades from caudal to cranial, with pulmonary vessels still visible,
in the lying patient possibly rounding out the marginal sinus as in the standing thorax,
in the lying patient apical compression and lateral distancing of the lung from the thoracic wall by effusion.
as a result of this and by compression of the lower lobe, a surface compression parallel to the thorax wall can arise.
in the left lateral position and horizontal beam path forms a horizontal Ausstoßlamelle (DD callus, Matrazenkante, Wäschefalte). This is the most sensitive radiological proof of effusion. The lower detection limit is 15 ml
X-ray sign of the encapsulated pleural effusion.




- in the gap
spindle-shaped or round tumor-like compression, which disappears with the resorption of the effusion: "vanishing lung tumor", "pseudotumor"

- subpulmonary
no meniscus sign.
The effusion superimposes parallel to the diaphragmatic curvature and is therefore misinterpreted as a diaphragmatic dome and diaphragmatic elevation
Left distally of the gastric bladder more than 2 cm from the lung base.
On the right side, the subpulmonary effusion is hardly diagnosable; Sometimes the diaphragmatic dome appears slightly laterally displaced. Sonography!

- on the chest wall
mostly dorsally located, therefore blurred paravertebral or hilar shadows in the p.a. image
sharply marked in the side image with edges running out on the thoracic wall

Seropneumothorax: When air enters the fluid-filled pleural space (during an efferent puncture), the fluid forms a horizontal mirror.

Sonographic proof of effusion:
missing echoes
reflective edge. Because of the underlying air-containing lung tissue, there is no distal echo enhancement as usual with liquids
An encapsulated effusion on the thoracic wall is sometimes difficult to differentiate from a likewise echoic lymphoma or neurogenic tumor.
Septa in the effusion indicate chambering. This is not visible on CT, but important for effusion drainage
Exudates show respiratory-dependent mobile linear structures (fibrin filaments?)
Exudates have a low, homogeneous echo increase
Exudates show a thickened pleura, especially on the diaphragm.
The distinction between the subpulmonary and intra-abdominal fluid in the computerized tomogram:
Diaphragm mark: If there is fluid in the infra and supradiaphragm, the diaphragm becomes visible. Pulmonary fluid lies outside the diaphragmatic arch, abdominal fluid lies within (central) the diaphragmatic arch.
Contour mark: The transition from pulmonary effusion to the liver or spleen is blurred, the transition from ascites to liver and spleen is sharply contoured.
Thigh sign: the pulmonary effusion spreads the diaphragmatic leg away from the spine.
Lever-back sign: Fluid dorsal to the right lobe of the liver is of pulmonary origin. The right lobe of the liver lies directly on the dorsal abdominal wall without any peritoneal coating, so that no fluid can collect there.
There may be delineation problems due to underlap atelectasis or to a caudally arched diaphragm.

The hemorrhagic effusion can be differentiated by CT from others because of the high density of the blood.

Computed tomography detects encapsulated effusions and localizes them precisely for a puncture.

Magnetic resonance tomography allows differentiation of the transudate, exudate, and chylothorax. An effusion is -
signal rich in the T2-weighted image.
Pleural effusions can have many causes, such as

- vascular (heart failure, pulmonary embolism, immunological diseases),
- tumorous: tumor cells are found in an outflow of a patient with bronchogenic carcinoma, the tumor is classified after T4 and is thus inoperable. Other outcomes include metastases of bronchial carcinoma or breast cancer, malignant lymphoma or mesothelioma,
- inflammatory (pneumonic, tuberculous); the effusion of a feverish patient without pulmonary infiltrates suggests a viral, mycoplasma or tuberculosis infection,
- traumatic,
- idiopathic,
- iatrogenic (drug-related) diseases.
Evidence of a malignant effusion are:
nodular or flat pleural thickening. But they are often very discreet.
It is also thought of abdominal causes, such as

- pancreatic diseases (so-called "sympathetic effusion" with increased amylase),
- subphrenic abscess,
- postoperative condition,
- kidney diseases,
- liver cirrhosis,
- Ovarian Ca (Meigs syndrome),
- Whipple's disease,
- peritoneal dialysis.
If suspected abdominal overview images should be made in the back and left lateral position.

Indications of an abdominal cause are:
intraabdominal free air,
intraperitoneal fluid levels,
Pancreatic calcifications in chronic pancreatitis,
Bile or kidney concrements,
Tumor-related intestinal displacement or intestinal atony (ileus).
The patient's medical history must be taken into account. In chronic renal failure, secondary heart failure may occur. If remission of other signs of decompensation results in pleural effusion and typical clinical signs such as sudden chest pain, shortness of breath, hemoptysis, pleural disease, decreased arterial PO2, or thrombophlebitis, the effusion is likely to be a manifestation of pulmonary embolism. Recurrent effusions without signs of heart failure may be due to rheumatoid arthritis or lupus erythematosus. The effusions are often the only sign of immunological disease.