[Medical Q&A] Do lung lobes have “neighbors”?

Planner: Chinese Medical Association

Reviewer: Zhou Xin, Chief Physician, First People's Hospital, Shanghai Jiao Tong University School of Medicine

As we all know, the normal lung is divided into the left lung and the right lung. The left lung is divided into the upper lobe and the lower lobe, and the right lung is divided into the upper lobe, the middle lobe and the lower lobe. In fact, there is another structure between the lobes - the fissure. This anatomical term is very vivid. It is like the neighbor of the lobe, like a crack, separating the lung into different lobes.

There are two types of fissures: oblique fissures and horizontal fissures. Oblique fissures separate the upper lobe from the lower lobe of the left lung, and also separate the upper lobe and middle lobe from the lower lobe of the right lung; horizontal fissures only exist in the right lung, separating the upper lobe from the middle lobe of the right lung. The fissures are actually thin layers of tissue formed by the pleura. There are usually no large blood vessels and bronchi inside, but there are some small blood vessels and lymphatic vessels passing through. Each lobe separated by a fissure has its own set of blood vessels and bronchi, which can ensure efficient gas exchange. The fissures can reduce the spread of infection or damage. If one lobe is infected or damaged, the fissures can limit the scope of its impact and protect other lobes from being affected. In X-ray and CT examinations, the fissures appear as linear shadows, which help doctors identify the location and structure of different lobes. In lung surgery, the fissures are also important anatomical landmarks that can help surgeons accurately locate and remove diseased lobes and preserve healthy lung tissue.