The costodiaphragmatic recess, also called the costophrenic recess or phrenicocostal sinus,
Retrieved May 2011 is the posterolateral fringe of the pleural space, a potential space around the

lung The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of ...

inside the pleural cavity. It is located at the acutely angled junction ("reflection") between the costal and diaphragmatic pleurae, and is interpreted two-dimensionally on

plain X-ray Projectional radiography, also known as conventional radiography, is a form of radiography and medical imaging that produces two-dimensional images by x-ray radiation. The image acquisition is generally performed by radiographers, and the images a ...

s as the costophrenic angle. It measures approximately vertically and extends from the eighth to the tenth

rib In vertebrate anatomy, ribs ( la, costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the ches ...

along the mid-axillary line.

Function

The

lungs The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either si ...

expand into this recess during forced

inspiration Inspiration, inspire, or inspired often refers to: * Artistic inspiration, sudden creativity in artistic production * Biblical inspiration, the doctrine in Judeo-Christian theology concerned with the divine origin of the Bible * Creative inspirat ...

; however, the recess never gets filled completely. During expiration, it contains nothing apart from gravitated serous fluid.

Clinical significance

Pleural effusions collect in the costodiaphragmatic recess when in standing position, and present on

s as "blunting" of the costophrenic angle. A thoracocentesis (pleural tap) is often performed here while a patient is in full expiration because of less risk of puncturing the lungs and thereby causing pneumothorax.drugs.com > costodiaphragmatic-recess
Retrieved May 2011

Imaging

anatomy Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having i ...

, the costophrenic angles are the places where the

diaphragm Diaphragm may refer to: Anatomy * Thoracic diaphragm, a thin sheet of muscle between the thorax and the abdomen * Pelvic diaphragm or pelvic floor, a pelvic structure * Urogenital diaphragm or triangular ligament, a pelvic structure Other * Diap ...

(''-phrenic'') meets the ribs (''costo-''). Each costophrenic angle can normally be seen as on

chest x-ray A chest radiograph, called a chest X-ray (CXR), or chest film, is a projection radiograph of the chest used to diagnose conditions affecting the chest, its contents, and nearby structures. Chest radiographs are the most common film taken in me ...

as a sharply-pointed, downward indentation (dark) between each hemi-diaphragm (white) and the adjacent chest wall (white). A small portion of each lung normally reaches into the costophrenic angle. The normal angle usually measures thirty degrees.

Pleural effusion

With pleural effusion, fluid often builds up in the costophrenic angle (due to gravity). This can push the lung upwards, resulting in "blunting" of the costophrenic angle. The posterior angle is the deepest. Obtuse angulation is sign of disease. Chest x-ray is the first test done to confirm the presence of pleural fluid. The lateral upright chest x-ray should be examined when a pleural effusion is suspected. In an upright x-ray, 75 mL of fluid blunts the posterior costophrenic angle. Blunting of the lateral costophrenic angle usually requires about 175 mL but may take as much as 500 mL. Larger pleural effusions opacify portions of the hemithorax and may cause mediastinal shift; effusions > 4 L may cause complete opacification of the hemithorax and mediastinal shift to the contralateral side.

References

External links