Evidence for successful gastric perfusion computed tomography with low-radiation dose.

Objective: To investigate how the blood flow analysis changes by varying the radiation dose of gastric perfusion CT (PCT) and to prove that a low-radiation dose of PCT is feasible.

Methods: 5 Beagle dogs were used in a crossover study with 6 groups of varying radiation doses. Iodixanol was IV administered at 3.0 mL/s, and cine CT was performed for 120 seconds. Blood flow maps were obtained from the acquired images using the maximum slope method.

Results: Significant differences in blood flow were observed between 80 kV at 50 mA and 120 kV at 100 mA and between 80 kV at 100 mA and 120 kV at 100 mA. Visual noise from the low tube current technique was absent in all color maps.

Conclusions: In gastric PCT, blood flow was calculated to be lower with imaging at a low-radiation dose than at a high-radiation dose. By considering that blood flow values change depending on the radiation dose, it was indicated that a low-radiation dose of gastric PCT is feasible.

Clinical relevance: These preliminary findings may have clinical applications in ischemic or oncologic gastric disease noninvasively, at low-radiation doses, and in a short time in the future. Since the contrast medium dose for PCT is low, the diagnostic value of CT examinations can be further improved by performing both conventional CT examinations and PCT at the same time.