Dual-energy CT to differentiate gallbladder polyps: cholesterol versus adenomatous

Dual-energy computed tomography (DE-CT) scans were acquired to identify cholesterol and adenomatous gallbladder (GB) polyps, which have not been well evaluated before surgery.

To evaluate the DE-CT findings of GB polyps 1.0-2.0 cm in size and differentiate between cholesterol and adenomatous polyps.

Forty-six patients with GB polyps were surgically treated from December 2017 to December 2019 and divided into two groups according to their postoperative pathologic results: a cholesterol group with 26 patients and an adenomatous group with 20 patients. All of these patients underwent DE-CT imaging with tube voltages of 80 kVp and 140 kVp within two weeks before surgery. Mean attenuation values were measured for every GB polyp at 80/140 kVp and at 40/140 keV. The mean attenuation value changes between 140 kVp and 80 kVp (MAVC_{140-80 kVp}) and mean attenuation value changes between 100 keV and 40 keV (MAVC_{100-40 keV}) were calculated.

The CT image parameters of all 46 patients with GB polyps were analyzed. There were significant differences in MAVC_{140-80 kVp} and MAVC_{100-40 keV} between cholesterol and adenomatous polyps (P <0.05); these values were positive for cholesterol polyps and negative for adenomatous polyps.

The unique energy spectrum information provided by DE-CT scans is helpful in differentiating between cholesterol and adenomatous polyps 1.0-2.0 cm in size.