Generating New CT Slice Images with Angiographic C-arm System DynaCT -- MEDICA - World Forum for Medicine


Siemens AG, Medical Solutions

Generating New CT Slice Images with Angiographic C-arm System DynaCT

Siemens Medical Solutions introduced DynaCT for the first time in Europe at the ECR (European Congress of Radiology) March, 4th - 8th, 2005 in Vienna, Austria. This new application enables users of angiographic C-arm systems to create soft tissue images based on the principles of CT. These CT like images allow soft tissue differentiation that enables, for instance, detection of intracranial hemorrhages and visualization of the brain tissue. This in turn supports decision making during interventions. It is all made possible by modern flat detector (FD) technology from Siemens.

Angiographic C-arm systems are designed to generate projection images. For several years, rotational angiography and their corresponding reconstruction methods have been able to generate and visualize 3D volumes from these projection images. This method, established in hospitals, was developed to display high contrast image content (bones, vessels with contrast agent, etc.). In combination with the flat detector, DynaCT now enables soft tissue differentiation. Clinical images, comparable to those generated by a CT scanner, can display organs, vessels or hemorrhages.

These new views using an angiography system open many new applications in neuroradiology, as well as abdominal or oncological interventions. Applications range from the visualization of vascular systems, with the ability to detect hemorrhages and changes in size, to support for drainage procedures, as well as tumor embolization and ablation. In many cases, computed tomography was previously used in these cases for imaging. With DynaCT, repositioning the patient from the angiography suite to a computed tomography facility is eliminated, which, in fact, was performed rarely because of the difficulty and increased risk. The time required often was enough to rule out the use of such measures.

Generating slice images at the C-arm system is extremely easy: the physician rotates the C-arm in a circle about the patient and performs a number of acquisitions in accordance with the protocol. Subsequently, images are reconstructed in the same manner as with a CT system and sent to the angiography system monitor. Within three minutes, the physician receives the results in the form of slice images, which can display objects of up to 10 HU (Hounsfield units) difference and 10 mm in size. Cranial hemorrhages, ventricles and cranial structures can be detected in these slice images. Additionally, tumors can be differentiated from healthy tissue.

Dr. Hideyuki Takano, the first to implement DynaCT in a clinical situation at the Chiba Cancer Center at Chiba/Japan requires the highest level of information possible from an imaging system to have an optimum decision-making basis to ensure fast and safe treatment for patients in cancer interventions. He underscores his requirements succinctly: "We could see the unexpected performance of DynaCT. In the near future it will be an indispensable function in the interventional field."

For Dr. Norbert Gaus, head of the Angiography, Fluoroscopic and Radiographic Systems product group at Siemens Medical Solutions, Dyna CT is the result of consistent use of flat detector technology: "DynaCT is a successful example of how we use our technological advantage to benefit our customers. The customer sees us as a leader in innovation. With the flat detector, we were motivated to view this technology as more than just a replacement for the image intensifier. Our developers consistently investigated what was possible with flat detectors. Generating slice images at the C-arm is certainly a milestone in interventional radiology.”

DynaCT is suited for use with all Siemens angiography systems with flat detectors. While the application is available with Axiom Artis dFA in a monoplane system, the physician can use DynaCT in a biplane system (Axiom Artis dBA) as well as a ceiling-mounted system (Axiom Artis dTA DynaCT). Artis systems that are already installed can be upgraded. DynaCT has FDA clearance for the USA.

Siemens Medical Solutions is one of the world's largest suppliers to the healthcare industry.The company is known for bringing together innovative medical technologies, healthcare information systems, management consulting, and support services, to help customers achieve tangible, sustainable, clinical and financial outcomes. From imaging systems for diagnosis, to therapy equipment for treatment, to patient monitors to hearing instruments and beyond, Siemens innovations contribute to the health and well-being of people across the globe, while improving operational efficiencies and optimizing workflow in hospitals, clinics, home health agencies, and doctors' offices. Employing approximately 31,000 people worldwide and operating in more than 120 countries, Siemens Medical Solutions reported sales of 7.07 billion EUR, orders of 8.12 billion EUR and group profit of 1,05 billion EUR for fiscal 2004.

Further information can be found under: