A federal district judge in Santa Ana, CA, has issued a preliminary injunction prohibiting General Electric from making, using or selling computed tomography bone mineral calibration phantoms. The phantoms are the subject of a patent infringement suit filed by Image Analysis of Irvine, CA.
Both Image Analysis and GE sell quantitative CT products for which the phantom is central, said Ben A. Arnold, president and founder of the smaller company.
QCT packages consist of the calibration phantom and accompanying software, which runs on either the CT scanner or a separate personal computer. Image Analysis has patents for both the phantom and software. No suit has been filed on the software patents, although the company is investigating that option, Arnold said.
The QCT systems are offered as add-ons to installed CT scanners. They sell for about $15,000, in contrast to $70,000 to $110,000 for stand-alone dual energy x-ray absorptiometry (DEXA) densitometers. QCT offers diagnostic advantages over DEXA in its ability to differentiate osteoporotic from normal subjects. The technique is also more reimbursable than DEXA, Arnold said.
"A CT scanner is a great imaging machine, but the numbers it produces are not reliable in that they are not calibrated against some standard. The calibration phantom is equivalent to bone and shaped and designed so that it can be put in the beam with the patient. The measurements in the calibration phantom are then cross-calibrated against the bone in the patient," Arnold said.
Image Analysis was formed in 1984 and introduced its QCT system in 1985. GE launched its QCT product two years later. The scanner vendor had an advantage in selling the system to its own CT user base, Arnold said.
"When GE offered the product, it was a major blow to our activity," he said.
GE is not the only scanner vendor selling QCT. Siemens also has a product, but no litigation has been filed against the German vendor. Siemens may have sold over 500 systems in Europe alone. Image Analysis has sold 700 QCT packages worldwide, while GE may have sold between 300 and 400 systems, Arnold said.
With about 5000 installed CT scanners in each of the three major imaging markets of the U.S., Europe and Japan, the potential market for QCT sales has barely been tapped, he said.
