Low-dose whole organ CT perfusion of the pancreas: preliminary study

To investigate the feasibility of low-dose whole pancreas CT perfusion in the clinical practice.

Sixty-one patients suspected pancreatic disease underwent low-dose whole pancreas CT perfusion scan (by body weight, group A: 70 kV, 120 mAs; group B: 80 kV, 100 mAs) and the individualized pancreas scan. Forty-six patients were enrolled. Perfusion characteristics, such as, blood flow, blood volume and permeability, were analyzed. The effective radiation dose of the whole pancreas CT perfusion and the total CT scan protocol were recorded. CT findings were histologically confirmed by surgical intervention or diagnostic puncture.

Of the 46 cases, 33 were pancreatic adenocarcinoma, 5 were solid-pseudo-papillary tumors of pancreas, 8 cases of pancreatic endocrine tumors on the perfusion study. There was significant interobserver agreement on the measurement of normal pancreatic CT perfusion parameters of group A (n = 28)and group B (n = 18), respectively (p > 0.05). For the normal pancreas, there was no significant difference on CT perfusion parameters between group A and group B (p > 0.05). There were significant differences on blood flow as well as blood volume between the pancreatic adenocarcinomas and the normal pancreas (p < 0.001), whereas no difference on the permeability (p > 0.05). The time to peak of the normal pancreas is 28.94 ± 4.37 s (range from 24 to 38 s). Different pancreatic tumors had different types of time attenuation curve (TAC). TACs were different between pancreatic adenocarcinomas and normal pancreas. The effective radiation dose of the whole pancreas CT perfusion of Group A and Group B were 3.60 and 4.88 mSv (DLP 246 and 325 mGy cm), respectively, and the total radiation dose was around 8.01-16.22 mSv.

Low-dose whole pancreatic CT perfusion can effectively reduce radiation dose, and provide the best phase for the individualized pancreas scan, which has great value in the clinical practice.