2024 年 44 巻 3 号 p. 101-108
Objective/Background
Previous reports have suggested that breath-hold (BH) three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) provides additional value with respiratory-gated 3D MRCP. Although these methods have been reported to suppress “respiratory artifacts,” the influence of gastrointestinal peristalsis around the target organs is not mentioned. On the other hand, the autonomic nervous system has been reported to affect gastrointestinal peristalsis. There are also reports that BH imaging influences venous blood flow through its involvement with the autonomic nervous system. We examined the effects of BH imaging on gastrointestinal peristalsis.
Methods
Seven healthy volunteers provided informed consent for our study. Gastrointestinal peristalsis was measured using cine magnetic resonance imaging (MRI) with two-dimensional (2D) FIESTA. Cine MRI data were analyzed using the normalized interframe difference method in MATLAB, focusing on the duodenum and gastric body. Three respiratory patterns—free breathing (FB) with assumed respiratory gating, BH at maximum inspiration (Insp-BH), and BH at maximum expiration (Exp-BH)—were employed. Hemodynamic changes resulting from BH methods were evaluated using 2D phase contrast, targeting the inferior vena cava (IVC). The blood flow signal (BFS) was examined for all phases of each respiratory pattern. Statistical analysis used one-way ANOVA.
Results
Peristaltic variation in the duodenum showed no significant differences among FB (2.03±0.86), Exp-BH (1.32±0.63), and Insp-BH (1.20±0.91). In the gastric body, no significant differences were observed between FB and Exp-BH or between Exp-BH and Insp-BH. However, a significant difference emerged between FB and Insp-BH (p<0.05). Regarding BFS, significant differences in IVC were noted between Exp-BH and Insp-BH, as well as between FB and Insp-BH (both p<0.01). Meanwhile, no significant difference was found between FB and Exp-BH.
Conclusions
Our study suggests that Insp-BH reduces venous blood flow and suppresses the influence of peristaltic variation.
