Philips readies Gemini PET/CT for production later this year

Hybrid scanner's journey covers a lot of ground

Philips has begun taking orders for Gemini, a hybrid PET/CT system that splits into two parts, which allows single-modality scanning on either component. Shipments are scheduled to begin later this year.

Right now Gemini is the only hybrid PET/CT device that features such separable parts. The dual-ring configuration-one for CT, the other for PET-reduces patient discomfort about tight spaces, thanks to the tapered bores and a gap in the center, while the ability to separate the two rings offers practitioners flexibility in patient examination and scheduling.

The engineering challenges of creating such a system were formidable. But there is more to the story than just engineering. When the first production-line copy of this hybrid scanner rolls onto the shipping dock later this year, Gemini will have completed an R&D odyssey.

The journey began as a collaboration between two independent companies, Philips Medical Systems and ADAC Laboratories. Their first attempt debuted on the floor of the RSNA meeting in November 2000 bearing the logos of both companies. The system was remarkably different from the current configuration. The pieces, ADAC's Allegro PET scanner and Philips' CT Aura, were locked together. Executives at the two firms, which merged a month later when Philips acquired ADAC, soon decided Gemini was going in the wrong direction.

"We realized that the initial design was quite similar to competitive products being developed," said Josh Gurewitz, vice president of marketing for nuclear medicine and PET at Philips. "At the same time, we realized that the biggest issue with these hybrid devices was going to be patient acceptance."

A patient revolt in the mid-1990s against claustrophobic scanners inspired the design of open MRI devices. The hybrid PET/CT originally developed by Philips and ADAC was stuck in the old claustrophobic thinking, which was also evident in the hybrids being developed by competitors. Seeking wider patient acceptance and a way to distinguish its product from the rest of the pack, a Philips design team proposed the open and flexible design that now characterizes Gemini.

They initiated another change as well. To nurture the perception of a world-class offering, Gemini had to include a multislice scanner, not the single-slice CT Aura with which they'd been working, Gurewitz said. The means for achieving this evolution soon came to hand. In July 2001, Philips announced its intention to buy Marconi Medical Systems. As the Marconi acquisition moved toward completion, Philips began looking to replace the CT Aura. Marconi's MX8000 CT scanner was a natural choice.

"Once we started looking at their CT product line, it became clear that they had the right technology for us," Gurewitz said. "One of the reasons Philips was so interested in Marconi was because of its multislice technology. That gave us the missing piece of the equation. We knew that combining that with our Allegro dedicated PET system and an open design was going to be a winner."

One month after Philips finalized its deal to acquire Marconi Medical Systems-a very short time in the design world-Philips was ready with a multislice version of the hybrid PET/CT.

"All the right pieces came together at the right time," Gurewitz said.

The second unveiling of Gemini, which occurred at the 2001 RSNA meeting, was a watershed event for Philips. It demonstrated with hardware what top Philips executives had been saying since the company began its buying spree with ATL some three years earlier-that Philips, with its multiple modalities and broad-based R&D, could shape new products in novel and innovative ways.

"Gemini has taken a lot of twists and turns over the last 24 months, but the bottom line is that the acquisitions (of ADAC and Marconi) led to a significantly better product," Gurewitz said. "It will have higher patient acceptance and much more flexibility in the way it can be used, and we think this will help propel the PET/CT market to greater heights."

Like other hybrid devices, Gemini enables clinicians to perform CT procedures when the PET component is not required. Mechanical separation, which neither the GE Discovery nor Siemens Biograph can offer, also enables easy access to the patient for interventional procedures.

According to Gurewitz, the ability to perform either modality alone may prove important to buyers. Because CT is a high-throughput exam, it may go a long way toward paying for these systems over time.

"If you look at the PET volume in a lot of institutions, it's often not enough to keep a PET system busy nonstop," Gurewitz said. "To be able to move the PET away and use Gemini for just CT we think will be fairly important."

On the downside, both the Biograph and Discovery are shipping. Gemini is not. And PET reimbursement fees are in flux, although Philips executives believe they will stabilize at a level supportive of wide scale PET scanning.

Hybrid scanners such as Gemini will have a much more specialized market, however. During 2001, vendors booked about 50 units for sale to customers in the U.S., according to Gurewitz. Compared with sales of other types of products, this is a drop in the bucket. But he believes this year will mark a major upturn and the market could more than double over the next three to five years.

That's good news for Philips, whose novel design will set the company apart from its competitors. So far, interest in the system has been high, Gurewitz said. And this may be only the first step for Philips in bringing new ideas together within and outside of nuclear medicine.

"The synergies here are huge," Gurewitz said.