Dual-energy CT with virtual monoenergetic images to improve the visualization of pancreatic supplying arteries: the normal anatomy and variations

Abstract

Background Pancreatic ductal adenocarcinoma (PDAC) remains a malignancy with poor prognosis, appropriate surgical resection and neoadjuvant therapy depend on the accurate identification of pancreatic supplying arteries. We aim to evaluate the ability of monoenergetic images (MEI [+]) of dual-energy CT (DECT) to improve the visualization of pancreatic supplying arteries compared to conventional polyenergetic images (PEI) and investigate the implications of vascular variation in pancreatic surgery and transarterial interventions. Results One hundred patients without pancreatic diseases underwent DECT examinations were retrospectively enrolled in this study. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) at 40-keV MEI (+) were significantly higher than those of PEI (p < 0.05). All subjective MEI (+) scores were significantly higher than those of PEI (p < 0.05). The visualization rates were significantly higher for posterior superior pancreaticoduodenal artery (PSPDA), anterior and posterior inferior pancreaticoduodenal artery (AIPDA, PIPDA), anterior and posterior pancreaticoduodenal arcade (APAC, PPAC), transverse and caudal pancreatic artery (TPA, PCA) at 40-keV MEI (+) than those of PEI (p < 0.05). However, there were no significant differences for visualizing anterior superior pancreaticoduodenal artery (ASPDA), inferior pancreaticoduodenal artery (IPDA), dorsal and magnificent pancreatic artery (DPA, MPA) between 40-keV MEI (+) and PEI (p > 0.05). Four types of variations were observed in the origin of DPA and three to five types in the origin of PSPDA, AIPDA and PIPDA. Conclusions 40-keV MEI (+) of DECT improves the visualization and objective and subjective image quality of pancreatic supplying arteries compared to PEI. Pancreatic supplying arteries have great variations, which has important implications for preoperative planning of technically challenging surgeries and transarterial interventions.

Dual-energy CT with virtual monoenergetic images and iodine maps improves tumor conspicuity in patients with pancreatic ductal adenocarcinoma

“…Moreover, an advanced modeled iterative reconstruction and tin pre-filtration for the high-kV tube were also employed to decrease the image noise. In addition, taking the SNR level into consideration is also necessary, although image noise is constantly implemented as an image quality indicator [ 13 ]. If the absolute noise level is clinically acceptable, increasing the SNR level could ensure the improvement of image quality.…”

“…Monoenergetic images (MEIs) acquired from different types of DECT (dual-source, rapid kV-switching, and dual-layer DECT) have been proven to improve tissue contrast [ 10 , 11 ]. MEI approximates the image derived from monoenergetic X-rays, in which iodine attenuation increases with the energy approaching the K-edge of iodine (33.2 keV) [ 12 , 13 ]. However, it is reported that due to the increased image noise at low keV levels, especially in abdominal examination, the clinical utility of MEI at < 70 keV is limited [ 5 , 14 ].…”

“…Recently, a third-generation dual-source DECT has been introduced to overcome this limitation, which allows for the reconstruction of monoenergetic image plus (MEI [+]) by using a noise-optimized monoenergetic algorithm [ 13 , 15 ]. Based on a spatial frequency-split recombination technique, both the higher-image contrast at lower energies and superior noise properties at higher energies are combined to optimize the image noise level [ 10 , 16 ].…”

Comparison of image quality of two versions of deep-learning image reconstruction algorithm on a rapid kV-switching CT: a phantom study

“…Our results showed a strong potential of the new version of DLSR to reduce the amount of iodine injected to the patients when using the 60 keV energy level. Indeed, several studies reported low iodine concentrations (lower than 5 mg/mL) measured for abdominal lesions [13][14][15][16][17][18][19]. The detection of these lesions is challenging, requiring higher iodine concentrations and/or radiation doses.…”

“…Among these developments, dualenergy CT (DECT) is of interest to optimise the amount of iodine injected [8][9][10]. Indeed, this technique offers a capacity to enhance the contrast of lesions using specific images such as virtual monoenergetic images (VMIs) [11][12][13][14] as compared to conventional CT images with single-energy (SECT). In addition, the use of iodine-specific images allows the radiologist to quantify the iodine concentration, which improves the characterisation of lesions in abdominal imaging [15][16][17][18][19].…”