Main articles: Lung
The 'Right lung' is divided into three lobes, superior, middle, and inferior, by two interlobular fissures:
Fissures
★ One of these, the
oblique fissure, separates the inferior from the middle and superior lobes, and corresponds closely with the fissure in the
left lung. Its direction is, however, more vertical, and it cuts the lower border about 7.5 cm. behind its anterior extremity.
★ The other fissure, the
horizontal fissure, separates the superior from the middle lobe. It begins in the previous fissure near the
posterior border of the lung, and, running horizontally forward, cuts the
anterior border on a level with the
sternal end of the fourth
costal cartilage; on the
mediastinal surface it may be traced backward to the
hilus.
Lobes
The middle lobe, the smallest lobe of the right lung, is wedge-shaped, and includes the lower part of the anterior border and the anterior part of the
base of the lung. (There is no middle lobule on the
left lung, though there is a
lingula.)
The superior and inferior lobes are similar to their counterparts on the
left lung.
Difference in size
The right lung, although shorter by 2.5 cm. than the left, in consequence of the
diaphragm rising higher on the right side to accommodate the
liver, is broader, owing to the inclination of the heart to the left side; its total capacity is greater and it weighs more than the left lung.
Impressions
On the mediastinal surface, immediately above the hilus, is an arched furrow which accommodates the
azygos vein; while running upward, and then arching lateralward some little distance below the apex, is a wide groove for the
superior vena cava and right
innominate vein; behind this, and nearer the apex, is a furrow for the
innominate artery.
Behind the hilus and the attachment of the
pulmonary ligament is a vertical groove for the
esophagus; this groove becomes less distinct below, owing to the inclination of the lower part of the esophagus to the left of the middle line.
In front and to the right of the lower part of the esophageal groove is a deep concavity for the extrapericardiac portion of the thoracic part of the
inferior vena cava.
Additional images
See also
★
Left lung
External links
★
Lung Lobes
★
★ - "Mediastinal surface of the right lung."
★
Diagram and quiz at cancer.gov
★
★
Cross section at univie.ac.at