Ralf W. Bauer MD, Presenter: Research Consultant, Siemens AG Speakers Bureau, Siemens AG

Freia Fessler, Abstract Co-Author: Nothing to Disclose

Julian Lukas Wichmann MD, Abstract Co-Author: Nothing to Disclose

Thomas Henzler MD, Abstract Co-Author: Nothing to Disclose

Josef Matthias Kerl MD, Abstract Co-Author: Research Consultant, Siemens AG Speakers Bureau, Siemens AG

Claudia Frellesen, Abstract Co-Author: Nothing to Disclose

Thomas Lehnert MD, Abstract Co-Author: Nothing to Disclose

Moritz Kaup, Abstract Co-Author: Nothing to Disclose

Jan-Erik Scholtz MD, Abstract Co-Author: Nothing to Disclose

Thomas Josef Vogl MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate a novel mono-energetic reconstruction algorithm with improved noise reduction for dual-energy CT of the pancreas.

71 patients with suspected pancreatic carcinoma underwent second- or third-generation dual-source dual-energy CT with arterial phase. Images were reconstructed as virtual 120 kV series (M_0.6) by linearly blending the spectral information of the high and low kV dataset and with the available standard mono-energetic application at a virtual mono-chromatic image impression at 40 keV and 55 keV. Additional image series were reconstructed with the novel “mono-energetic plus” application promising improved noise reduction (40+ and 55+). Image quality was compared between all series with respect to noise, signal of healthy pancreatic tissue and tumor tissue, SNR and pancreas-to-lesion contrast (CNR).

32 carcinomas were detected. Compared to the standard M_0.6 series signal of healthy pancreas tissue was significantly higher for all mono-energetic reconstructed images ( M_0.6: 92 HU; 40: 280 HU; 40+: 290 HU; 55: 166 HU; 55+: 167 HU). With the standard mono-energetic algorithm, noise gradually increased with lower energies (55: 21 HU; 40: 37 HU), while the novel “mono-energetic plus” algorithm was able to keep the noise at a constantly low level similar to and not significantly different from the M_0.6 series (8 HU for 55+ and 40+; 9 HU for M_0.6). Consequently, SNR of the pancreas was significantly superior in the 40+ and 55+ than in the 40 and 55 standard series (40.1 and 23.1 vs. 10.1 and 8.8) and outperformed the M_0.6 series (10.9). Likewise, pancreas-to-lesion contrast was highest in the 40+ series (16.4) followed by the 55+ series (7.1) and thus significantly higher than in any of the other series (M_0.6: 4; 40: 3.3; 50: 2.5).

A novel noise-optimized algorithm for reconstruction of mono-energetic images from second- and third-generation dual-source dual-energy CT data can significantly improve image quality in the diagnosis of pancreatic carcinoma.

The challenging diagnosis of small pancreatic adenocarcinoma with faint tumor-to-lesion contrast may be enhanced with this dedicated processing of dual-energy CT data, being vital for the patient.

Bauer, R, Fessler, F, Wichmann, J, Henzler, T, Kerl, J, Frellesen, C, Lehnert, T, Kaup, M, Scholtz, J, Vogl, T, A Noise-optimized Mono-energetic Reconstruction Algorithm Enhances the Conspicuity of Pancreatic Adenocarcinomas on Dual-Source Dual-Energy CT.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14006371.html