Siemens unveils interventional robot at RSNA 2007

The mechanical precision seemed otherworldly - at the very least, out of place - as Siemens Medical Solutions' Artis zeego executed one interventional pirouette after another. It turned, then twisted, raised, then lowered, its C-arm mounted x-ray tube and solid-state detector during its debut demonstration at RSNA.

The offspring of a novel marriage between industrial robotics and advanced C-arm technology, Zeego features a robot arm that would be at home on an automotive assembly line but is new to an interventional suite.

"It is comparable to what people may know from the car industry, when you look at welding robots," said Claus Grill, vice president of angiography, cardiac, and x-ray systems for Siemens Medical Solutions.

Advanced robotics allow Artis zeego to place its center of rotation anywhere in a sphere around the patient. This enables complex movements such as tilted table scans in the peripherals. Software keeps the robot arm a safe distance away from the patient and table.

In clinical use at two U.S. sites, zeego's precision translates into angulations and projections that can be reproduced time and again. The onlookers on the RSNA exhibit floor took in a performance as entertaining as it was instructive.

The robotic arm turned and twisted the single-plane imaging chain, adjusting the isocenter as though to fit the procedure or height of the physician. It spun the C-arm as if to acquire data volumes that, when reconstructed using DynaCT, would produce results comparable to those of some CT systems, according to company executives. Once its job was done, zeego parked the C-arm near the top of the exhibit.

Although the work-in-progress system is restricted to investigational use, Artis zeego began operating the second week of November at St. Luke's Episcopal Hospital in Houston and at the University of Virginia Health System in Charlottesville. Luminaries at those facilities report that the multiaxis robot arm allows virtually unrestricted C-arm positioning, according to Siemens. The system can provide cross-sectional imaging that cannot be achieved with traditional C-arm systems.

Large-volume syngo DynaCT visualizes the whole abdomen or the entire liver, an advantage when performing chemoembolization and biopsies. Neurointerventional procedures are made easier with views of the skull and the neck as well as expanded views of the spine, said Tom Truesdell, Siemens director of product marketing.

"Two separate volumes can be acquired - one on either side of the isocenter - and reconstructed into a larger volume," Truesdell said. "So it allows the whole abdomen or the whole chest to be seen, from the spine on up through the soft tissues."

The multiaxis arm makes zeego the most versatile member of Siemens' new Artis zee family of interventional systems. The other five in the family rely on conventional floor-mounted, ceiling-mounted, multipurpose, biplane (one small and one large detector), and biplane twin (two large detectors) configurations. These were seen previously in the Axiom Artis systems that are now exiting the Siemens line-up.

Turning the Axiom Artis into the Artis zee is an advanced imaging chain designed to acquire and process data into detailed 2D and 3D images. Shared by the family are intuitive, menu-driven workflows that streamline procedures and system movements as well as ergonomic tableside controls.

Two applications - syngo iPilot and iGuide - differentiate the zee family from its Axiom predecessor. Syngo iPilot speeds the precise navigation of catheters, using 3D reconstructions superimposed onto live 2D fluoroscopy as well as 2D roadmaps or digital subtraction angiography. This provides real-time updates of C-arm and table movements along with zoom and source-to-image distance changes.

"You give the user a 3D impression that you can fade in and fade out during the procedure, making it easier to know if the guide wire has to go anterior, posterior, or whatever direction," Grill said. "That is available in real-time and at tableside."

Syngo iGuide assists in needle-based procedures, which had begun shifting to CT-guided interventions but now can be reclaimed by the zee interventional suite guided by syngo DynaCT.