Clinical implementation of contrast-enhanced four-dimensional dual-energy computed tomography for target delineation of pancreatic cancer.
BACKGROUND AND PURPOSE
The accurate delineation of pancreatic tumor with respiratory motion is challenging. This study demonstrates the application of contrast-enhanced four-dimensional dual-energy computed tomography (CE-4D-DECT) for tumor delineation and assesses the objective and subjective image quality.


MATERIAL AND METHODS
Twelve patients underwent CE-4D-DECT, and quantitative spectral analysis was performed on the resulting virtual monochromatic images (VMI) to determine the optimal VMI (O-VMI) with the highest contrast-to-noise ratio (CNR). The objective value of the CNR between pancreatic parenchyma and tumor, and the subjective measurement with five-point scale were compared between O-VMI, standard VMI (S-VMI, 77 keV) and single energy CT (SECT, 120 kVp).


RESULTS
The CNR was the highest in the VMI at 60 keV, and the corresponding CNR in the O-VMI (3.4) was significantly higher (p < 0.05) than that in the S-VMI (2.4) and the SECT (2.7). The overall mean subjective measurements among 4 radiation oncologists were higher for the O-VMI over the S-VMI and SECT with respect to overall image quality (4.0, 3.3 and 3.7, respectively), tumor enhancement (3.4, 2.6 and 3.2, respectively), and vessel delineation (4.2, 3.6 and 4.2, respectively).


CONCLUSIONS
The O-VMI derived from the CE-4D-DECT demonstrated its superiority over the S-VMI and SECT in depicting pancreatic tumor.
['Ohira|Shingo|S|', 'Wada|Kentaro|K|', 'Hirata|Takero|T|', 'Kanayama|Naoyuki|N|', 'Ikawa|Toshiki|T|', 'Karino|Tsukasa|T|', 'Nitta|Yuya|Y|', 'Isono|Masaru|M|', 'Ueda|Yoshihiro|Y|', 'Miyazaki|Masayoshi|M|', 'Koizumi|Masahiko|M|', 'Teshima|Teruki|T|']
D000368:Aged D000369:Aged, 80 and over D005260:Female D056973:Four-Dimensional Computed Tomography D006801:Humans D008297:Male D008875:Middle Aged D010190:Pancreatic Neoplasms D011857:Radiographic Image Interpretation, Computer-Assisted D015900:Radiography, Dual-Energy Scanned Projection D012189:Retrospective Studies D059629:Signal-To-Noise Ratio
Pancreatic cancer 4DCT Contrast enhanced Dual energy