This document provides an overview of pleural effusion findings on chest x-rays. It defines the pleural space and reasons fluid may accumulate there. Key signs of pleural effusion on chest x-ray include a blunted costophrenic angle, meniscus sign, and elevated hemidiaphragm. Loculated effusions can form adhesions and appear as smooth, poorly defined masses that droop on upright images. Different views and positions are useful to detect various amounts of pleural fluid.

1. Pleural effusion X-ray
findings
Jeetendra

2. Normal chest X-ray(PA view)
Index:
• a  aorta;
• ca  carina;
• cl  clavicle;
• cpa  costophrenic angle;
• g  gastric air bubble;
• la  left atrium;
• p  main pulmonary artery;
• s  scapula;
• t  trachea.

3. Normal chest X-ray(PA view)
Index:
• Aaorta;
• Apw aortopulmonary window;
• Cap cardiophrenic angle;
• g  gastric air bubble;
• ip  interlobar (or descending)
pulmonary artery;
• L  liver;
• lv  left ventricle;
• rts  right tracheal (or paratracheal)
stripe;
• sp  spleen;

4. Normal chest X-ray(PA view)
Index
• A  aorta
• Ajl anterior junction line
• Apw aortopulmonary window
• Ip interlobar (or descending)
pulmonary artery
• Pjl posterior junction line

5. Normal Chest X-ray (lateral view)
Index:
• a  aorta
• bi  bronchus intermedius
• cpa  costophrenic angle
• d  diaphragm
• e  esophagus
• ivc  inferior vena cava
• lpa  left pulmonary artery
• lul  left upper lobe bronchus
• lv  left ventricle
• m  manubrium
• mf  minor fissure
• MF  major fissure
• rpa  right pulmonary artery
• rul  right upper lobe bronchus
• rv  right ventricle
• st  sternum
• svc  superior vena cava
• t  trachea
• v  vertebral body

6. Introduction to pleural space
• Contain 2 layers i.e. Visceral and Parietal pleura
• Visceral pleura is outer lining of the lung
• Parietal pleura is lining of the chest cavity
• Normally, these surfaces are smooth and are separated by a minimal
amount of pleural fluid
• Provides nearly friction-free environment for movement of the lung
within the thorax
• Normally contains no more than 3 to 5 mL of pleural fluid

7. Reasons for accumulation of fluid
• Increase pulmonary capillary pressure (transudate)
• congestive heart failure
• hypoproteinemia
• fluid overload
• liver failure
• nephrosis
• Alter thoracic vascular or lymphatic pathways
• Alter pleural capillary or lymphatic permeability(Exudate)
• Infection or inflammation
• pulmonary embolism
• neoplasms
• Affect diaphragmatic peritoneal and pleural surfaces
• pancreatitis
• subphrenic abscesses
• liver abscesses
• ovarian tumors
• peritonitis
• ascites

8. Pleural effusion
• Most common radiographic sign is pleural meniscus
• Volume of fluid to produce pleural meniscus within costophrenic
angle varies in individual

9. Clinical findings
• Decreased breath sounds
• Dullness to percussion
• Decreased tactile fremitus
• Egophony
• Pleural friction rub

10. Pleural effusion(lateral view)
• Approx 100 mL of pleural fluid
will cause appreciable blunting of
the posterior costophrenic angle
on the lateral view

11. Pleural effusion(PA view)
• 200 mL will cause blunting of the
lateral costophrenic angle on the
PA projection in an upright
patient

12. Pleural effusion(lateral decubitus view)
• A lateral decubitus chest
radiograph, with the side
containing the pleural effusion
placed down (dependent),
demonstrate smaller amounts of
free-flowing pleural effusions
• 1 millimeter of thickness of
pleural fluid in the lateral
decubitus = approx 20 mL of
pleural fluid

13. Sub-pulmonic pleural effusions
• Sub-pulmonic pleural
effusions elevate the lung
base
• Mimics an elevated
diaphragmatic leaflet
• On the left side, a marked
separation (>2 cm) of the
lung from the stomach
bubble suggests a sub-
pulmonic effusion. Right Sub-pulmonic effusion
with elevated right hemi-
diaphargm

14. The Same thing.. Rt. Sub-pulmonic
effusion

15. The apex of the curvature at the lung base is shifted laterally,
and its slope slants sharply towards the lateral costophrenic
sulcus
The rock of Gibraltar sign

16. Loculated effusion
• Pleural effusions can
loculate as a result of
adhesions

18. Features
• Typical configuration of a loculation along the chest wall, often described
as pleural or extrapleural sign
• Angles of interface between the pleural “mass” and the chest wall are
obtuse, and the mass displays tapered borders
• Surface of the “mass” is usually smooth, poorly marginated when seen
PA, and only partially visualized when displayed in an oblique
projection (“incomplete margin sign”)
• Homogeneous content
• “mass” droops on upright images owing to its liquid content

19. References
• Michael Y. M. Chen, Thomas L. Pope, David J. Ott. Basic Radiology.
2nd ed. Mc. Grow hill. P-115-9.
• Cochard, Larry R.,Netter, Frank H. Netter's Introduction to Imaging.
Elseiver. P-37-9.

20. Thank you!!