Inferior Orientation of the Colored Medial Segment of the Right Lung

Description

Seen from an inferior orientation, the right lung is presented with emphasis on the colored medial bronchopulmonary segment of the middle lobe (segmentum mediale, S5). The segment lies anteromedially within the middle lobe, bounded superiorly by the horizontal fissure and separated posteriorly and inferiorly from the lower lobe by the oblique fissure, while its medial surface faces the mediastinum. Along the medial contour, you would expect the cardiac impression and adjacent mediastinal pleura to define the concavity, with the diaphragmatic surface forming the broad inferior base. Small segment. Clear borders. Segment-level anatomy matters when you plan or interpret limited lung resection. The medial segment is supplied by the segmental bronchus B5 and its accompanying segmental pulmonary artery branch (A5), and it drains via segmental veins that often run within the intersegmental planes, a relationship surgeons respect during VATS middle lobectomy and S5 segmentectomy to limit air leak and preserve venous drainage of neighboring segments. Middle lobe disease also localizes differently than lower lobe pathology, and the S4/S5 region is a familiar site for recurrent atelectasis and infection in right middle lobe syndrome when the middle lobe bronchus is narrowed by lymphadenopathy or inflammation. Use this plate in thoracic anatomy teaching to reinforce bronchopulmonary segmentation, fissural anatomy, and the mediastinal versus diaphragmatic surfaces of the right lung, and in surgical texts or CME modules covering segmentectomy planning and intraoperative orientation from the diaphragmatic side. It also fits radiology instruction when correlating segmental distribution on axial CT with operative segment maps. Anatomical accuracy verified by SciePro's Medical Advisory Board.