Type:
Educational Exhibit
Keywords:
Computer Applications-Detection, diagnosis, CT, Thorax, Lung, Cardiac, Oedema
Authors:
C. A. Arboleda Vallejo1, M. I. carvajal2, M. Perez1; 1Medellin, Antioquia/CO, 2medellin/CO
DOI:
10.1594/ecr2018/C-2146
Background
Acute pulmonary oedema is a manifestation of decompensated heart failure,
the usual radiological pattern in chest X-rays corresponds to bilateral symmetrical opacity occupying the central areas of the lung parenchyma,
hence the classic sign of “butterfly shadow".
Fig. 1: Sign of “butterfly shadow", refer to a pattern of bilateral perihilar shadowing.
There are two types of pulmonary edema:
- Pulmonary cardiogenic edema or increased hydrostatic pressure.
- Non-cardiogenic pulmonary edema or normal hydrostatic pressure edema due to increased pulmonary permeability,
acute lung injury or acute respiratory distress syndrome.
Tabla 1.
Cardiogenic Pulmonary edema VS Non-cardiogenic pulmonary edema
Radiological Description |
Cardiogenic |
Non-cardiogenic |
Cardiac Silhouette |
Normal or increased |
Normal |
Width of the Vascular Pedicle |
Normal or increased |
Normal or diminished |
Vascular Distribution |
Normal or Inverted |
Normal |
Distribution of Edema |
Central |
Patches or Peripheral |
Pleural Effusion |
Present |
Absent |
Septal Lines |
Present |
Absent |
Air Broncogram |
Absent |
Present |
However the asymmetric pulmonary edema is another type of less common radiological manifestation,
in some series corresponds up to 2.1% of patients with acute pulmonary edema.
This entity is a challenge for diagnosis,
with multiple differential diagnoses including pneumonia,
bronchopaspiration and alveolar hemorrhage.
Atypical pulmonary edema can occur in any pathology that affects the pulmonary parenchyma,
circulation and lymphatic drainage.
In the majority of the literature,
there is an association with severe mitral regurgitation and superior right predominance.
Unilateral pulmonary edema can occur in:
- Severe mitral valve insufficiency with eccentric regurgitant jet
- Re-expansion of a pneumothorax
- Diseases of the pulmonary parenchyma
- Unilateral sympathectomy
- Compression of the pulmonary veins by a myxoma or atrial thrombus
- Rapid drainage of a pleural effusion.
Unilateral pulmonary edema due to mitral regurgitation is characterized by:
- Predominance in right upper lobe
- The Jet of blood flows through the incompetent mitral valve
- It is mainly directed to the right pulmonary vein causing increased pressure.
- Interferes in venous return