hi let's talk about the surfaces and gross features of the lungs the lungs are bilaterally
paired organs there is a right and a left lung and let's divide the two there and i've given you both
costal and mediastinal views but let's discuss how we can differentiate right versus left and
the answer is quite simple the right lung has a middle lobe and associated
with in association with it the left lung does not so let's continue our grid here
right and left costal and mediastinal surface so um
both left and right lungs have apices and the apex of the lung is
oriented superiorly towards the cupula at the the root of the neck so that's the the portion of the
lung that is aimed towards the cervical portion of the parietal pleura um there are also costal
surfaces which are everything that we can see in this superior row here the costal surfaces are
facing outwards towards the costal pleura there's a mediastinal surface the mediastinal surface
is facing towards the mediastinal pleura and we can always identify that because that is where the
hilum can be found and then finally the diaphragmatic surface is probably best
viewed from the mediastinal surface we can see that that is a very richly concave surface that
is going to align with the concavities i'm sorry the convexities of the cupili of the diaphragm
now each lung on its mediastinal surface is going to have a hilum and that hilum is going
to contain a root of the lung and each root of the lung is going to contain bronchi here we can
see the uh the primary bronchus has been uh cut at this point um over here there is the bronchus
there are also pulmonary arteries i'll be doing these in blue to denote that the heart conducts
oxygen poor blood from the right ventricle out via the pulmonary trunk pulmonary arteries
to the uh the capillary beds of the alveoli um you can see that pulmonary artery there these are in
very close association with the tracheobronchial tree and then each lung also has two pulmonary
veins which i'll be outlining in red here to denote the oxygen-rich blood which is flowing back
to the left atrium to be distributed through systemic circulation now each lung has a number of
lobes and so the right lung has three lobes there is a superior also called the upper lobe
the middle and then an inferior also known as the lower lobe whereas the left lung
only has a superior and an inferior these lobes are separated from one another by fissures and
these fissures are lined by the visceral pleura so separating superior from inferior lobes are
oblique fissures and on the right lung it will also separate the inferior lobe from the middle
so oblique fissures run obliquely that's helpful these are also known as the major fissures
and then on the right lung there is also a a horizontal fissure called the minor fissure
and then finally unique to the left lung is the cardiac notch the cardiac notch
accommodates the apex of the heart and at the inferior border of the cardiac notch
we have this tongue-like projection called the lingula so there's the cardiac notch
and there is the lingula of the left lung so we've discussed the various surfaces
and fissures and lobes
and gross structures of the right and left lungs thank you very much for your time