New Version of Siemens’ Definition Edge Brings Dual Energy to Routine CT Imaging

  • New TwinBeam Dual Energy¹ for single-source CT enables simultaneous imaging at two different energy levels
  • Dual energy images available for immediate assessment
RSNA 2014: South Building, Hall A, Booth 1934

CHICAGO--()--With the new version of the SOMATOM Definition Edge CT system, which debuts at the 100th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA), Nov. 30-Dec. 5 in Chicago, Siemens Healthcare will establish the benchmark for acquiring single-source dual energy images in clinical routine. The innovative TwinBeam Dual Energy X-ray tube concept of the relaunched SOMATOM Definition Edge enables simultaneous imaging at two different energy levels for the first time in single-source computed tomography (CT).

In dual energy imaging, the same region of the body is examined using two different energy levels. The resulting two datasets offer more detailed information about tissue composition that extends beyond pure morphology. However, in cases where data have been acquired using fast kV-switching or dual layer detector technology, dual energy imaging has had significant drawbacks. In the past, single-source dual energy images acquired with these methods were excluded from routine clinical use because the X-ray tube did not emit the two energy spectra simultaneously, but rather in succession through rapid switching or spectral separation at the detector side. With kV-switching, the segmentation of the measuring points impairs image quality significantly due to the limited data per energy level. Also, increased X-ray doses are inevitable because the dose cannot be modulated to reduce radiation.

Beam split into two energy spectrums

The innovative tube design of Siemens’ new TwinBeam Dual Energy technology featured in the relaunched SOMATOM Definition Edge splits the X-ray beam into two different energy spectra prior to reaching the patient. The result: simultaneous generation of dual energy images. “With this technology, we are laying the groundwork for dual energy imaging in single-source computed tomography to be used in routine procedure,” says Walter Märzendorfer, CEO for Computed Tomography and Radiation Oncology at Siemens Healthcare.

Siemens’ approach to dual energy imaging technology in general offers tissue characterization that could be applicable in clinical situations like the evaluation of kidney stones to differentiate between uric acid and non-uric acid stones, which provides additional diagnostic information. Another example: When examining liver lesions, the material information contained in the dual energy imaging acquisition can indicate liver lesions, with information that is based on the determination of contrast uptake in the tumor (Iodine Maps).

The new version of the SOMATOM Definition Edge also can simplify the radiology workflow considerably. Unlike other single-source dual energy CT imaging, the Edge’s acquired dual energy datasets are preprocessed intelligently directly after acquisition. The datasets also can be sent automatically by the Edge to the picture archiving and communication system (PACS) with the aid of Siemens’ new Fast DE Results² technology.

Siemens employs a unique and efficient approach to acquiring TwinBeam Dual Energy image data, providing dose optimized protection. In addition, dose-reducing Siemens technologies can be used in combination with TwinBeam Dual Energy on the new version of the SOMATOM Definition Edge CT system, including ADMIRE (Advanced Modeled Iterative Reconstruction),³ the model-based iterative reconstruction procedure that Siemens released recently on the SOMATOM Force CT system. ADMIRE’s algorithms can reduce X-ray doses even further, achieving excellent image resolution and reduced pixel noise even at low doses.

Iterative metal artifact reduction

To further improve not only the quality of dual energy examinations but also conventional CT scans using the SOMATOM Definition Edge, Siemens is introducing iMAR4 – a new iterative algorithm for metal artifact reduction. With iMAR5, metal artifacts can be reduced. Installed SOMATOM Definition Edge and SOMATOM Definition AS+ CT scanners can be retrofitted with TwinBeam technology, iMAR and ADMIRE (in combination with the Stellar detector), enabling Siemens to deliver a complete solution that exceeds the expectations for low-dose high-quality CT imaging.

¹ TwinBeam Dual Energy is pending 510(k) clearance and is not yet commercially available in the United States.

² Fast DE Results is pending 510(k) clearance and is not yet commercially available in the United States.

³ In clinical practice, the use of ADMIRE may reduce CT patient dose depending on the clinical task, patient size, anatomical location, and clinical practice. A consultation with a radiologist and a physicist should be made to determine the appropriate dose to obtain diagnostic image quality for the particular clinical task.

4 iMAR is designed to yield images with a reduced level of metal artifacts compared to conventional reconstruction if the underlying CT data is distorted by metal being presented in the scanned object. The exact amount of metal artifact reduction and the corresponding improvement in image quality achievable depends on a number of factors, including composition and size of the metal part within the object, the patient size, anatomical location, and clinical practice. It is recommended to perform iMAR reconstruction in addition to conventional reconstruction.

5 iMAR is pending 510(k) clearance and is not yet commercially available in the United States.

Siemens AG (Berlin and Munich) is a global technology powerhouse that has stood for engineering excellence, innovation, quality, reliability and internationality for more than 165 years. The company is active in more than 200 countries, focusing on the areas of electrification, automation and digitalization. One of the world's largest producers of energy-efficient, resource-saving technologies, Siemens is No. 1 in offshore wind turbine construction, a leading supplier of combined cycle turbines for power generation, a major provider of power transmission solutions and a pioneer in infrastructure solutions as well as automation, drive and software solutions for industry. The company is also a leading provider of medical imaging equipment – such as computed tomography and magnetic resonance imaging systems – and a leader in laboratory diagnostics as well as clinical IT. In fiscal 2014, which ended on September 30, 2014, Siemens generated revenue from continuing operations of €71.9 billion and net income of €5.5 billion. At the end of September 2014, the company had around 357,000 employees worldwide. Further information is available on the Internet at


for Journalists
Siemens Healthcare
Jeff Bell, 610-448-1477


for Journalists
Siemens Healthcare
Jeff Bell, 610-448-1477