One of the things I teach young medical students is to recognise collapse of individual lobes of the lung on a Chest X-ray. The one lobe that I insist they know about is a common one – collapse of the left lower lobe. It is important to know the rules that tell you that it is there. By contrast the left upper lobe is difficult to detect when an important collapse has occurred, it is not common so I insist that the radiology registrars are able to recognise it. I tell them that in order to pass an exam, all medical students must know the lower lobe collapse, but registrars must also be able immediately to see an upper lobe collapse. The difficulty is that the left lower lobe, as it collapses, gets more and more dense, whereas because of different anatomy the upper lobe on that side becomes less dense and more difficult to see. I tell them that we are given a divine clue – the upper lobe as it collapses pulls the blood vessels out of place and makes a prominent bulge appear. If recognised, the bulge, or “knob” as I like to call it, gives you the diagnosis.
The X-ray in this image is from a person with a malignant cancer of the left upper lobe bronchus which has caused it to collapse. The “knob” can just be seen marked with an overlying pale blue ring.
I layered several images to achieve this scattered effect similar to an erupting volcano. A green leaf and a green plastic tank with lime splatters down the side were overlaid by the reflections in a polished orange tile, all using a Difference mode. The lime splatters were isolated, copied, textured and laid on top, then the X-ray was copied and inserted to allow more detail to shine through.