Siemens Healthcare's approach to delivering dose-neutral dual energy images obtained on SOMATOM computed tomography (CT) scanners using TwinBeam Dual Energy technology is now commercially available. With this availability, which affects the SOMATOM Definition Edge and SOMATOM Definition AS CT systems, Siemens sets the benchmark for acquiring single-source dual energy images in clinical routine. Dual energy imaging has gained momentum as a clinical imaging tool amid pressure to reduce the cost and frequency of medical imaging while increasing quality of care. With dual energy imaging, only one CT study is acquired, but the imaging data can be used in a variety of additional methods to improve clinical decision-making. Siemens' TwinBeam Dual Energy approach is unique in that it enables acquisition of this data without introducing additional radiation – a dose-neutral dual energy approach.
Dose-neutral dual energy imaging entails the examination of the same body region using two different energy levels. The resulting two datasets offer detailed information regarding 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 encountered significant drawbacks. In the past, single-source dual energy images acquired via 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, image quality is impaired 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-splitting innovation in dose-neutral dual energy
The innovative design of Siemens' TwinBeam Dual Energy technology enables a dose-neutral approach. Via a split filter within the X-ray tube, the X-ray beam is divided into two different energy spectra prior to reaching the patient. The result: simultaneous generation of dose-neutral dual energy images
"With the availability of TwinBeam Dual Energy technology on the SOMATOM Definition Edge and SOMATOM Definition AS systems, Siemens Healthcare provides the tools necessary for health care facilities to realize dose-neutral dual energy imaging in single-source CT," said Douglas Ryan, Vice President, CT Business Line, Siemens Healthcare North America. "This technique paves the way for dual energy's use in routine procedures and especially in challenging cases. Now, Siemens can increase diagnostic confidence while helping providers control healthcare costs."
