The Calcium Score is "A number reflecting the degree and extent of calcium deposits in the walls of the coronary arteries, as demonstrated by cardiac computed tomography." So yes, an actual area in your LAD.

(CT imaging is sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior.)

http://www.radiologyinfo.org/en/inf...g=ct_calscoring

With my usual critical eye to medical procedures, I do wonder how the skill of the radiologist may impact the score, but also know that many image tests are now first "read" by a computer. When calcium is detected in a slice, likely its size, location and thickness is measured by computer for its degree and extent. The radiologist will then recheck those areas of calcium, but as you can see in samples, it appears those bright white spots would be hard to miss and simple to measure accurately by computer. Compare these to the 3D computer assisted diagnostic mammograms I discuss yearly with a chief radiologist....these seem easier to read to my completely untrained eye.