Growing bone densitometry market drives development of new platforms

HCFA reimbursement move slams peripheral studies

The dramatic surge of the U.S. bone densitometry market in 1996is helping to propel the development of new bone measurement systemsdesigned to ride the growth wave. The trend was evident at lastmonth's Radiological Society of North America meeting, where establishedbone measurement companies like Lunar and Hologic rolled out newproducts while new players like Fuji unveiled their entries intothe market.

New product introductions were found across a wide range of bonemeasurement technologies: Hologic and Lunar showed enhancementsto their high-end product lines; Norland Medical displayed a CT-likedensitometer; two makers of quantitative CT products, Image Analysisand IRIS, emphasized leaps forward in user productivity, whileanother, MindWays (formerly MindWaves) Software, displayed a 3-DQCT product; and CompuMed hoped to build on digital technologyto offer a tabletop x-ray device.

The big news over the long haul could be plans by Norland Medicalof Fort Atkinson, WI, to market a CT-like device for bone mineralanalysis. XCT 3000, which is already available in the PacificRim, Europe, Japan, and South America, generates a cross-sectionalimage of bone, similar to what is possible on a full-blown CTscanner.

The image quality is magnitudes less than that of CT scanners,but Lewis Harrold, Norland vice president of product development,said the image is still good enough to see the biomechanics ofthe leg and hip bone, potentially allowing evaluation of patientresponse to drug therapy.

Another possibility is for orthopedists to scan patients followingimplant surgery, since the implant can be differentiated frombone. The big advantage is that XCT 3000 is compact enough toput in a doctor's office. An application for marketing in theU.S. will be submitted to the Food and Drug Administration, althoughthe company declined to state when it plans to file. A smallerversion, XCT 2000, which is capable of scanning the forearm, hasbeen cleared by the FDA and is priced below $50,000.

Norland is best known for p-DEXA, a low-cost desktop peripheraldensitometry unit whose appeal to buyers took a hit in Novemberwhen the Health Care Financing Administration (HCFA), which administersMedicare, lowered the reimbursement for peripheral densitometry(densitometry at sites such as the forearm) from $124 per scanto $37.57. By comparison, reimbursement for axial (spine and hipbone measurement) slipped downward only a few dollars from $124to $121.16.

At the RSNA meeting, Norland dropped the price of its peripheralunits from $32,500 to $25,000. Despite the HCFA change, interestin these units has been strong and may get stronger, accordingto Harrold.

"The drop in reimbursement is mostly affecting p-DEXA andit is affecting it in a very positive way, because before (theannouncement of HCFA policy), the rules were unclear," hesaid. "Now HCFA has clearly said what it will reimburse."

Norland also hopes to buff its image as a provider of high-endsystems by eventually offering XCT 3000 globally, intending tocapitalize on interest in table-based systems.

New offerings from Lunar and Hologic. Market leaders Lunar andHologic have the advantage in the premium segment, however, becauseboth have reputations for high-end instruments. In its RSNA booth,Lunar unveiled a new high-performance bone densitometer, DPX-IQ,which can perform a scan in one minute (SCAN 12/4/96). The system,which should begin shipping in the first quarter of 1997, is optimizedfor clinical use, offering the potential of scanning 100 patientsper day. Prime among its advantages, in addition to speed, issoftware that simplifies data interpretation.

"We've taken what is a very complex report and narrowed itdown to just a few numbers—comparison to the young adult populationand to an age-matched population," said David Weissburg,market manager for densitometry at Madison, WI-based Lunar. "Thisway we can show the absolute score of bone density."

The reference is an aggregate drawn from more than a dozen differentstudies totaling some 3000 women, he said.

Hologic of Waltham, MA, also expanded the capabilities of itsproduct line with the introduction of QDR 4500 Elite, the company'snewest addition to the Acclaim series of table densitometers.

"This new model is building on the very strong technologycore of QDR 4500," said Wade Fox, Hologic director of marketing.

Elite offers a more powerful computer, enhanced graphics, anda high-quality printer, in combination with software that reduceseffort and promises increased productivity for users. The modulardesign of the system allows software upgrades as they become availablefrom the company. The installed base of QDR 4500 densitometerswill be able to upgrade in early 1997 to the Elite configurationfor about $8000.

CompuMed of Manhattan Beach, CA, wants to put a portable x-raydevice based on charge-coupled device (CCD) technology in physicians'offices. The filmless system, tentatively dubbed OsteoView, woulddigitally translate x-rays into bone mineral measurements basedon data regarding bones in the hand. The technology is being developedunder license with the University of Massachusetts, which holdsa patent on the use of CCDs for doing quantitative BMD measurements.

Andrew Lisiecki, CompuMed vice president of technology, believesthat OsteoView could be a commercial product in about a year.The company offers an absorptiometry system that generates OsteoGrams,radiographs of the hand that are interpreted by its partner Merck,which is using the technology to promote its osteoporosis drugFosamax (SCAN 9/13/95).

"With (the desktop) OsteoView system, the exam could be donein the physician's office in a relatively short period of timewith results immediately available," Lisiecki said.

CompuMed last month also announced a technology development agreementwith Varian Associates of Palo Alto, CA, in which CompuMed willdevelop a new generation of x-ray densitometers based on Varian'samorphous silicon digital detectors. CompuMed will receive exclusiveworldwide marketing rights to the detectors for appendicular bonemass measurement and automated arthritis detection. CompuMed isscheduled to receive a pre-510(k) detector evaluation kit earlythis year.

QCT vendors branch out. Another company developing a cost-effectivebone measurement device is Image Analysis of Columbia, KY. Thevendor is working on a desktop bone densitometer that presidentBen Arnold hopes will be in clinical trials within six months.

"It is a modification of the x-ray source, the detector,and the calibration method that is different from conventionalDEXA devices, allowing me to build a device that is significantlyless expensive to manufacture," Arnold said.

No other details about the product are available, except thatits list price will likely be less than $40,000.

The development of such a product will be a major change in directionfor the company. Image Analysis has been the standard-bearer ofquantitative CT since the company's introduction nearly a decadeago of a phantom-based system that allows bone analysis on standardCT scanners. Calcium hydroxyapatite reference samples are positionedwith the patient in the region of interest (ROI) of the CT scan.Data coming off the CT are interpreted by software to isolatebone mineral densitometry (BMD) measurements of trabecular bone.

At the RSNA meeting, Image Analysis unveiled a new version ofthe analysis portion of the system, with highly automated softwarerunning on a Sun Microsystems workstation. The software, whichhas been patented by the company, automatically locates the ROI,calculates the measurements, and generates a color-coded report.

"We have taken keystrokes out of the operation, put in error-checkingroutines, put in quality assurance measurements, and made it veryeasy for the operator to use," Arnold said.

Image Analysis technology has been marketed by GE for severalyears, but at the RSNA conference GE chose to highlight the productat its booth for the first time, recognizing not only the growinginterest in BMD but also the sophistication of the new Image Analysisproduct.

Like Image Analysis, IRIS (Institute for Radiological Image Sciences)offers a QCT product, but one that does not require the use ofa phantom. At the RSNA show, the company highlighted the DICOMcompatibility of its PC-based PC/QCT product, which is licensedfor sale by Picker International. The new capability allows thePC to pull data directly off an Ethernet network, rather thanhaving to download data from the scanner to a diskette.

"They can just basically push the images to the PC and whenthere is a slow period, the technologist can go over and processthe reports," said Steve Dyer, a radiological physicist atIRIS, which is based in Frederick, MD.

Another quantitative CT product is QCT PRO, which seeks to exploitCT's ability to provide 3-D data sets. The software, developedby MindWays Software of South San Francisco, CA, runs on a PC,yet has the power to do 3-D serial image registration, which promisesto reduce patient repositioning errors. BMD measurements of thehip, spine, and other sites can be performed using either 2-Dor 3-D data sets.

"Working with a 3-D data set, it gives you the equivalentof 1-mm resolution in all dimensions, as opposed to the conventionalQCT type of technique where you take a single image and you hopethat the patient hasn't moved from the time that you do your scoutview," said Christopher Cann, one of the developers of theQCT software at MindWays.

The software also has the potential to be applied to new QCT applications,including coronary artery calcification analysis.

"There is a scoring system (for calcification) and we havedone some work in terms of trying to develop that further,"Cann said. "That is a work-in-progress."

Data for this type of analysis are currently found only on ImatronUltrafast CT scanners.

Finally, Fuji Medical Systems USA of Stamford, CT, got into thebone densitometry act at the RSNA meeting with a modificationof its FCR computed radiography reader. FCR DX-A consists of softwarethat can be added to an FCR workstation for bone densitometryapplications. Fuji's CR plates can be used with any x-ray system,enabling clinicians to conduct bone densitometry without havingto buy a dedicated system. FCR DX-A is being tested overseas,and U.S. marketing will begin when the system has 510(k) clearance,according to the company.