Right Lung Odd Lobe is an anatomic variant of the right lung, which is usually caused by an abnormality in the course of the odd vein. Normally, during the early development of the embryonic vasculature, the singular vein crosses the right lung cusp and anchors itself to the right mediastinum, above the root of the lung. However, if the normal movement of the saphenous vein is blocked, it presses the right lung apex downward. In this case, the singular vein and its associated pleura may become embedded in the right lung apex, and lung tissue develops around it. A deep downward fold, the cleft, is formed, which divides the upper lobe of the right lung into two parts, the medial part of which is the right lobe of the lung. It should be noted that the right lobe itself is usually asymptomatic and the clinical significance of its formation remains unclear. It is usually an occasional finding or is detected by chest X-ray or CT scan for other pathologies, and does not need to be treated if it is not associated with other pathologies.