Artificially colored 3D rendering of a high resolution computed tomography of a normal thorax of a 37 year old man who presented with unspecific breathing problems, published with written informed consent. The anterior thoracic wall, the airways and the pulmonary vessels anterior to the root of the lung have been digitally removed in order to visualize the different levels of the pulmonary circulation. Markings:

• Pulmonary arteries: blue
• Pumonary veins (and also the abdominal wall): red
• The mediastinum: yellow
• The diaphragm: violet