AN ANALYSIS OF VARIATIONS OF THE BRONCHO-VASCULAR PATTERNS OF THE RIGHT MIDDLE LOBE IN FIFTY CHINESE LUNGS / 解剖学报

ABSTRACT

The middle lobe of the right lungs of 50 Chinese adults were dissected. Their shape, broncho-vascular pattern and interrelationship were studied. A superior angle, hitherto not mentioned in the literature, was identified in 76% of the specimens. In the lungs studied, 84% of the bronchus of the middle lobe bifurcated into a lateral and a medial segmental bronchus, 12% bifurcated into a superior and an inferior segmental bronchus, and in 4% trifurcated into three bronchi. Surface representation of the segmental bronchi of the right middle lobes was examined. The arterial supply of the middle lobe varied from one to three branches. 76% of the cases were supplied by two arteries. The arterial patterns of the middle lobe have been grouped into four types. The middle lobe was usually drained by one to four veins, 56% of the specimens being with only one vein. According to the tributaries of the veins, four types of venous pattern were recognized, most of them (80%) being emptied into the superior pulmonary vein. In 80% of our specimens, an intersegmental vein has been identified. There are only 24% of our specimens in which the vascular pattern was in accordance with that of the bronchial tree.