Impact of noise-optimized virtual monoenergetic dual-energy computed tomography on image quality in patients with renal cell carcinoma. Issue 97 (December 2017)

• Record Type: Journal Article
• Authors: Martin, Simon S.; Wichmann, Julian L.; Pfeifer, Sophia; Leithner, Doris; Lenga, Lukas; Reynolds, Michael A.; D'Angelo, Tommaso; Hammerstingl, Renate; Gruber-Rouh, Tatjana; Vogl, Thomas J.; Albrecht, Moritz H.
• Is Part Of: European journal of radiology. Issue 97(2017)
• Page Start: 1
• Page End: 7
• Publication Date: 2017-12
• Subjects: Computed tomography -- Post-processing -- Renal cell carcinoma -- Image quality -- Oncology; Medical radiology -- Periodicals; Radiology -- Periodicals; Radiologie médicale -- Périodiques; Medical radiology; Periodicals; 616.075705
• DOI: 10.1016/j.ejrad.2017.10.008
• Languages: English
• ISSNs: 0720-048X

Abstract

Highlights: DECT enables post-processing of noise-optimized virtual monoenergetic images. VMI+ reconstructions at low-keV levels significantly improve image quality of RCC. Highest CNR and tumor-to-cortex ratios were observed for 40-keV VMI+ series. Highest scores for RCC lesion delineation were assigned for 40-keV VMI+. Abstract: Objective: The aim of this study was to evaluate the impact of a noise-optimized virtual monoenergetic imaging (VMI + ) reconstruction technique on image quality and lesion delineation in patients with renal cell carcinoma (RCC) undergoing abdominal dual-energy computed tomography (DECT). Materials and methods: Fifty-two patients (33 men; 61.5 ± 13.6 years) with RCC underwent contrast-enhanced DECT during the corticomedullary and nephrogenic phase of renal enhancement. DECT datasets were reconstructed with standard linearly-blended (M_0.6), as well as traditional virtual monoenergetic (VMI) and VMI+ algorithms in 10-keV increments from 40 to 100 keV. Contrast-to-noise (CNR) and tumor-to-cortex ratios for corticomedullary- and nephrogenic-phase images were objectively measured by a radiologist with 3 years of experience. Subjective image quality and RCC delineation were evaluated by three independent radiologists. Results: Greatest CNR values were found for 40-keV VMI+ series in both corticomedullary- (8.9 ± 4.9) and nephrogenic-phase (7.1 ± 4.6) images and were significantly higher compared to all other reconstructions ( P < 0.001). Furthermore, tumor-to-cortex ratios were highest for 40-keV nephrogenic-phase VMI+ (2.1 ± 3.5; P ≤ 0.016), followed by 50-keV and 60-keV VMI+ (2.0 ± 3.2 and 1.8 ± 2.8, respectively). Qualitative image quality scored highest for 50-keV VMI+ series in corticomedullary-phase reconstructions and 60-keV in nephrogenic-phase reconstructions ( P ≤ 0.031). Highest scores for lesion delineation were assigned for 40-keV VMI+ reconstructions ( P ≤ 0.074). Conclusion: Low-keV VMI+ reconstructions lead to improved image quality and lesion delineation of corticomedullary- and nephrogenic-phase DECT datasets in patients with RCC.