The nuclear medicine market is in a state of flux. Sales were unremarkable last year -- flat for gamma cameras, slightly up for PET/CT scanners -- but new technological advances and product introductions are generating interest as well as new users.
The nuclear medicine market is in a state of flux. Sales were unremarkable last year - flat for gamma cameras, slightly up for PET/CT scanners - but new technological advances and product introductions are generating interest as well as new users.
The gamma camera market in the U.S. was mixed in 2004. Revenues dropped to $355 million from $365 million in 2003, according to consolidated industry numbers. But the total number of units shipped increased slightly, from 1145 to 1165.
The most excitement occurred in markets for hybrid imaging technology, specifically PET/CT and SPECT/CT. The PET equipment market is being driven almost entirely by PET/CT sales, which rose only slightly from about $310 million in 2003 to $315 million in 2004. This was a marked slowdown from double-digit growth in 2003 over the previous year.
Developers of multislice SPECT/CT are now installing products at luminary sites. This move sparked industry speculation that these hybrids will make gamma cameras obsolete, much the way PET/CTs decimated the demand for stand-alone PET scanners.
Markus Lusser, vice president of Siemens Nuclear Medicine division, agreed that SPECT/CT will have an impact on gamma camera usage, but he questions how much.
"We're not expecting a dramatic flip, like the one we experienced with PET and PET/CT, where almost 100% of the market is now PET/CT sales," he said. "Something like that won't happen in the gamma camera world."
Lusser expects, however, that in one to three years between 15% and 25% of all gamma cameras sold will be some kind of SPECT/CT system.
"This is certainly an interesting trend, and the major vendors are all committed to SPECT/CT," he said. "We're already shipping SPECT/CT systems."
Siemens' multislice SPECT/CT family, the TruePoint Symbia, provides the option of combining a dual- or a six-slice CT with the company's e.cam dual-detector gamma camera.
Ian Farmer, senior vice president and general manager of Philips Medical System's nuclear medicine division, agreed that the most significant recent development in gamma cameras is the transition to SPECT/CT equipment. SPECT/CT provides attenuation correction that improves the quality of nuclear medicine scans, he said. CT used with the SPECT data localizes the tumor with functional information combined with the anatomic information.
"The excitement in the gamma camera market is the improved diagnostic quality you get from a SPECT/CT system, and that is what will drive the market," Farmer said.
He pointed out that this has important implications for oncology, specifically prostate cancer, as clinicians can localize tumors with ProstaScint.
"It has been very challenging to identify and localize the disease," he said. "SPECT/CT equipment allows you to diagnose and stage the cancer more effectively."
Farmer said SPECT/CT also shows great promise in cardiology.
"Clinicians can acquire perfusion data, to see where ischemia exists in the heart muscle, and then correlate that with CT angiography, to look at the artery and observe stenosis," he said. "Functional and anatomic information is correlated."
For the time being, however, SPECT/CT has barely had an impact on the gamma camera marketplace, as the vendors of multislice hybrids - Philips and Siemens - are just completing their first luminary installations. Nuclear medicine sales therefore hinge on dedicated gamma cameras, most of which are built around variable-angle detectors.
"Historically, variable angle has been the largest segment, but that is beginning to decline, as customers start to evaluate the type of technology they will buy in the future. They're now beginning to buy SPECT/CT systems," he said. "Meanwhile, the cardiology segment remains pretty healthy."
Currently, Philips promotes two configurations of its Precedence SPECT/CT system, which is combined with the multislice Brilliance CT platform: one with six slices (intended for oncology) and the other with 16 slices (designed for cardiology).
"If the customer chooses to buy the six-slice, we have a way to provide them with an onsite upgrade to 16 slices, if they choose to do that," Farmer said.
Philips has also upgraded its 16-slice Gemini PET/CT to support cardiovascular assessments as well as investigation of Alzheimer's disease.
GE Healthcare is also exploring multislice SPECT/CT, with installations of a prototype system at several sites around the world. In addition, the company is featuring a gamma camera called Infinia.
"This provides the option of adding the Hawkeye, which is the CT tube and the detector," said Ian Brown, the company's sales and marketing manager for SPECT/CT. "Its main area of use is localization."
For the private cardiology segment, GE offers a gamma camera called the Millennium Myosight.
Despite technological developments, including SPECT/CT, projected growth rates in the near term are expected to top out between 3% and 5%. Some of this growth will come from cardiology, which typically uses dual detectors fixed at a 90° angle. Demand for variable angle may slip, according to Farmer. But SPECT/CT will more than make up for this slippage.
"The marketplace is at a transition point, as customers are evaluating whether their next piece of equipment should be a replacement variable angle or a SPECT/CT," he said. "A large number are moving to SPECT/CT."
Like the rest of nuclear medicine, PET/CT is changing. IMV Medical Information Division reports that, in 2003, the number of PET/CT scanners and PET scanners installed were evenly split. Between 2004 and 2006, the percentage of PET systems will slip to just 10% of total sales in the U.S. PET/CT is proving valuable in treatment planning and disease management, as it can clearly localize a tumor or its spread.
"Hybrid imaging has gained widespread acceptance and garnered a growing interest in its potential for monitoring therapeutic delivery," said Patrick O'Day, global product manager for PET/CT at GE Healthcare.
The shift from PET to PET/CT is one of the most dramatic changes to affect the imaging community in decades. This change is only now entering its final stages, Lusser said.
"There has been a dramatic shift from dedicated PET to the hybrid scanners," he said. "Three years ago, we still had about 70% dedicated PET, and only 25% in the world were PET/CT. But the coin has flipped. Now there is a little less than 5% dedicated PET and 95% PET/CT. That is a clear indicator that the anatomic image coupled with the functional image is increasing clinical confidence in the ability to diagnose."
Use of this hybrid technology is expanding beyond oncology and into cardiology and neurology. Administratively, O'Day said, the market is being driven by expanded reimbursements and growing acceptance among healthcare insurers.