Topography of the Lungs – Lungs, mediastinum and cardiac valves

00:00 Our focus here, on this slide, is to understand the topography of the lungs and you’ll need to think about the superior topography or limit of each lung versus its inferior limit. So, first, let’s start with the superior limit of the lung and we see the apex of the right lung projecting above the clavicle.

00:33 We also see the apex of the left lung projecting above the left clavicle. And if we take a posterior view of the apices of the lungs, they’ll have a vertebral level relative to C7, the vertebra prominens. The distance above the clavicle is about 2.5 cm, which would be equivalent to 1 inch. The inferior limits of the lungs are going to depend along which line of axis we’re looking at or viewing. And we will describe three axes. One will be midclavicular. One will be on the lateral side of the thoracic wall, midaxillary. And then posteriorly, we’ll have one that runs along either side of the vertebral column and that’ll be a paravertebral vertical axis. If we start with the midclavicular, going to midaxillary, going to the paravertebral, the inferior limits of the right lung and the left lung will be at rib 6, midclavicular, midaxillary. The lung will extend down to rib 8 and then posteriorly, the inferior limit of the right lung and the left lung will extend down to the level of your 10th rib. So, it’s 6, 8, 10.