Digital radiography has been growing by leaps and bounds. Demand in the U.S. jumped 41% in 2004, 32% the next year, and 25% the year after that. Then, suddenly, in 2007, the market flattened. So far this year, it has shown no signs of recovering.

Some vendors framed the change as reflecting an increasingly challenging marketplace. Many hospitals are strapped for cash and unable to swing the purchase of comparatively expensive DR products, said Aaron Ybarra, product manager for x-ray equipment at Toshiba America Medical Systems. M. Thomas Boon, president and CEO of Imaging Dynamics Company, laid much of the blame for the lackluster demand on fears of a pending recession.

But, as with so many things, one's assessment of the market will depend on how one looks at it. Penny Maier, director of marketing for Fujifilm Medical Systems USA, said the DR market last year showed continued strength, as vendors turned in results comparable to those of the previous record-setting year.

"We wouldn't have so many vendors in this market if it wasn't a viable one," Maier said.

The competitive nature of the market is good news for radiologists and the places they work. The price of the average DR unit has fallen 18% over the last four years, while the number of units sold to sites in the U.S. has more than doubled. Different configurations&emdash;for example, detectors based on amorphous silicon arrays versus a complementary metal oxide semiconductor (CMOS) or charge-coupled device (CCD)&emdash;command different prices. And increased volumes have driven down overall prices. But, lately, engineers have started thinking outside the DR box.

Companies such as SwissRay offer products that use a single detector to do table and upright scanning, rather than depending on the old standby of separate upright and table-mounted detectors. Detector supplier Trixell has come up with a wireless detector that can be positioned to take views not possible with a mounted sensor. Fuji has turned computed radiography into DR with machines that self-read CR phosphor plates, delivering performance comparable to traditional DR products.

Philips Healthcare has taken it a step further. The company has completely done away with the debate over CR versus DR systems by developing products that are designed to be configured with either or both technologies, depending on what the customer wants.