The explosive growth of PET machines.

In year 2001, there were only one PET scanner in greater Montreal area. Today, there are seven--five in public hospitals, and two in private clinics. Why the explosive growth? Cost, of course. As PET/CT combined scanner got introduced to the market, the scanning time required for each patient cuts in half. The availability of CT images also provided much better anatomical reference for the PET images, which provide functional information. Of course, the installation of specially designed medical cyclotron doesn't hurt either. As turn-key devices, medical cyclotrons produce FDG's needed by PET scanner.

This growth of PET scanners makes me think about the growing popularity of digital SLR cameras. Yep, not much similarity between the two devices, but similar economic principle. As price of digital SLR cameras dropped below $1000, they became popular. As popularity grows, manufacturers ramped up production, and further reduces prices. Of course, this in turn causes more people to buy something that was reserved for serious hobbyists. The end result is a huge growth in total dollar amount of dSLR's sold. Same thing in PET/CT scanners. As costs per patient drop, the increase in number of scans more than make up for it. The end result is a fast growing segment of the industry.

Unlike pure research, the cost per patient will always be a deciding factor in health care.