Kai Roman Laukamp1,2,3, Vivian Ho1,2, Verena Carola Obmann1,2,4, Karin Herrmann1,2, Amit Gupta1,2, Jan Borggrefe3, Simon Lennartz3, Nils Große Hokamp1,2,3, Nikhil Ramaiya1,2. 1. University Hospitals Cleveland Medical Center, Department of Radiology, Cleveland, OH, USA. 2. Case Western Reserve University, Department of Radiology, Cleveland, OH, USA. 3. Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany. 4. Institute of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Bern, Switzerland.
Abstract
BACKGROUND: In abdominal imaging, contrast-enhanced computed tomography (CT) examinations are most commonly applied; however, unenhanced examinations are still needed for several clinical questions but require additional scanning and radiation exposure. PURPOSE: To evaluate accuracy of virtual non-contrast (VNC) from arterial and venous phase spectral-detector CT (SDCT) scans compared to true-unenhanced (TNC) images for the evaluation of liver parenchyma and vessels. MATERIAL AND METHODS: A total of 25 patients undergoing triphasic SDCT examinations were included. VNC was reconstructed from arterial and venous phases and compared to TNC images. Quantitative image analysis was performed by region of interest (ROI)-based assessment of mean and SD of attenuation (HU) in each liver segment, spleen, portal vein, common hepatic artery, and abdominal aorta. Subjectively, iodine subtraction and diagnostic assessment were rated on 5-point Likert scales. RESULTS: Attenuation and image noise measured in the liver from VNC were not significantly different from TNC (TNC: 54.6 ± 10.8 HU, VNC arterial phase: 55.7 ± 10.8 HU; VNC venous phase: 58.3 ± 10.0 HU; P > 0.05). VNC also showed accurate results regarding attenuation and image noise for spleen, portal vein, and abdominal aorta. Only iodine subtraction in the common hepatic artery in the arterial phase was insufficient which was confirmed by the subjective reading. Apart from that, subjective reading showed accurate iodine subtraction and comparable diagnostic assessment. CONCLUSION: VNC from the arterial and venous phases were very similar to TNC yielding mostly negligible differences in attenuation, image noise, and diagnostic utility. Inadequate iodine subtraction occurred in hepatic arteries in the arterial phase.
BACKGROUND: In abdominal imaging, contrast-enhanced computed tomography (CT) examinations are most commonly applied; however, unenhanced examinations are still needed for several clinical questions but require additional scanning and radiation exposure. PURPOSE: To evaluate accuracy of virtual non-contrast (VNC) from arterial and venous phase spectral-detector CT (SDCT) scans compared to true-unenhanced (TNC) images for the evaluation of liver parenchyma and vessels. MATERIAL AND METHODS: A total of 25 patients undergoing triphasic SDCT examinations were included. VNC was reconstructed from arterial and venous phases and compared to TNC images. Quantitative image analysis was performed by region of interest (ROI)-based assessment of mean and SD of attenuation (HU) in each liver segment, spleen, portal vein, common hepatic artery, and abdominal aorta. Subjectively, iodine subtraction and diagnostic assessment were rated on 5-point Likert scales. RESULTS: Attenuation and image noise measured in the liver from VNC were not significantly different from TNC (TNC: 54.6 ± 10.8 HU, VNC arterial phase: 55.7 ± 10.8 HU; VNC venous phase: 58.3 ± 10.0 HU; P > 0.05). VNC also showed accurate results regarding attenuation and image noise for spleen, portal vein, and abdominal aorta. Only iodine subtraction in the common hepatic artery in the arterial phase was insufficient which was confirmed by the subjective reading. Apart from that, subjective reading showed accurate iodine subtraction and comparable diagnostic assessment. CONCLUSION: VNC from the arterial and venous phases were very similar to TNC yielding mostly negligible differences in attenuation, image noise, and diagnostic utility. Inadequate iodine subtraction occurred in hepatic arteries in the arterial phase.
Authors: Amit Gupta; Verena Carola Obmann; Michelle Jordan; Simon Lennartz; Markus Michael Obmann; Nils Große Hokamp; David Zopfs; Lenhard Pennig; Gina Fürtjes; Nikhil Ramaiya; Robert Gilkeson; Kai Roman Laukamp Journal: Quant Imaging Med Surg Date: 2021-01
Authors: Simon Lennartz; Kai Roman Laukamp; Yasmeen Tandon; Michelle Jordan; Nils Große Hokamp; David Zopfs; Lenhard Pennig; Markus Obmann; Robert C Gilkeson; Karin A Herrmann; Nikhil Ramaiya; Amit Gupta Journal: Abdom Radiol (NY) Date: 2021-03-14
Authors: Christoph Stern; Dimitri N Graf; Samy Bouaicha; Karl Wieser; Andrea B Rosskopf; Reto Sutter Journal: Skeletal Radiol Date: 2022-02-11 Impact factor: 2.128
Authors: Jasmin A Holz; Hatem Alkadhi; Kai R Laukamp; Simon Lennartz; Carola Heneweer; Michael Püsken; Thorsten Persigehl; David Maintz; Nils Große Hokamp Journal: Sci Rep Date: 2020-12-09 Impact factor: 4.379
Authors: Julius Henning Niehoff; Matthias Michael Woeltjen; Kai Roman Laukamp; Jan Borggrefe; Jan Robert Kroeger Journal: Diagnostics (Basel) Date: 2021-12-16