thoracoscopy

noun

tho·​ra·​cos·​co·​py ˌthōr-ə-ˈkäs-kə-pē, ˌthȯr- 

plural thoracoscopies

: examination of the chest and especially the pleural cavity by means of a thoracoscope

… specializes in thoracoscopy, which permits examination of the lungs or other parts in the chest cavity without making a large incision.

—The Tampa Tribune

called also pleuroscopy