DEXA firms confer on standards

Four leading suppliers of dual-energy x-ray absorptiometry (DEXA)systems have agreed to cooperate in an effort to develop standardsand adopt phantom technology that will allow cross-calibrationof their DEXA equipment. The move is unusual in the typicallydog-eat-dog bone densitometry market.

Russell Nord, Norland's director of R&D, brought the companiesand interested clinicians together at the 1990 Radiological Societyof North America meeting in November, said Joel Blank, vice presidentof marketing for Norland.

While no concrete steps toward standardization were taken atthat meeting, the firms agreed to continue the negotiations. Asecond meeting will be held next month in Bad Reichenhall, Germany,during the 8th International Workshop on Bone Densitometry, Blancsaid.

The densitometry firms in the group include Norland, Lunarand Hologic from the U.S., and Sopha from France.

"We are attempting to formalize this task force into astandards group with its own identity, and then let this groupevolve into the organization that develops standards for bonedensitometry," Blank said.

Norland has suggested that a whole-body phantom it has developedmight be used as a standard for the industry. Others, however,might be more inclined to use a phantom built by a third party.An attempt was made two years ago to use a phantom made by RadiationMeasurements (RMI), but Hologic rejected it, said Richard B. Mazess,chairman and president of Lunar.

Standardization will be helpful to some users who like to compareabsolute numbers from the different machines, Mazess said. Cross-comparisonsare possible today, however, since all the vendors provide resultsof exams on young normal patients measured on same machine, hesaid.

"For example, a person who is 10% below young normal ona Lunar machine is going to be 10% below young normal on a Hologicor Norland system," Mazess said.

What would be more helpful to clinicians is to have all vendorsuse one calibration system, he said. This would be difficult toaccomplish, however, because the DEXA systems do not determineregions of interest for spinal and other exams in a consistentfashion across vendors, he said.

BRIEFLY NOTED:

• GE Medical has apparently changed its policy of usingonly a 3M laser imaging protocol with its new scanner digitalprinter ports (SCAN 2/27/91). Kodak and GE have signed an agreementthat enables GE customers to order the Kodak laser printer alongwith their scanners, said Catherine M. Burzik, manager of imageand information management for Kodak.

"Prior to this (agreement), we were not on a list of laserprinters that could be bought with GE modalities," she toldSCAN.

GE sales representatives will receive a commission on the Kodaklaser printer sales, Burzik said.