Department of Radiology, University Hospital Freiburg, Hugstetter Straße 55, 79106 Freiburg, Germany.
Obes Surg. 2011 Jan;21(1):95-101. doi: 10.1007/s11695-010-0317-6.
Laparoscopic sleeve gastrectomy (LSG) is generally considered a restrictive procedure. However, studies with nuclear medicine techniques have demonstrated that gastric motility changes occur following LSG. These motility changes could represent complementary mechanisms of weight loss. Therefore, we analyzed the stomach motility before and after LSG by means of dynamic MRI.
In this prospective pilot study, five female patients with a mean BMI of 51.6 kg/m(2) underwent MRI 1 day before LSG and 6 days and 6 months after LSG. Dynamic steady-state free precession sequences were used to analyze the gastric motility after ingestion of 500 ml water with a temporal resolution of 0.86 s. Axial image stacks were also repeatedly acquired to determine the intragastric fluid volume over time.
Mean excess body mass index loss was 60.6% after 6 months. Dynamic analysis showed that antral propulsive peristalsis was preserved immediately after surgery and during follow-up, but fold speed increased significantly from 2.7 mm/s before LSG to 4.4 mm/s after 6 months. The sleeve itself remained without recognizable peristalsis in three patients and showed only uncoordinated or passive motion in two patients. Consequently, the fluid transport through the sleeve was markedly delayed, whereas the antrum showed accelerated propulsion with the emptying half-time decreasing from 16.5 min preoperatively to 7.9 min 6 months after surgery.
Owing to the LSG procedure, the stomach is functionally divided into a sleeve without propulsive peristalsis and an accelerated antrum. Accelerated emptying seems to be caused by faster peristaltic folds.
腹腔镜袖状胃切除术（LSG）通常被认为是一种限制型手术。然而，采用核医学技术的研究表明，LSG 后胃动力发生变化。这些动力变化可能代表了减肥的补充机制。因此，我们通过动态 MRI 分析 LSG 前后的胃动力。
在这项前瞻性试点研究中，5 名平均 BMI 为 51.6 kg/m2 的女性患者在 LSG 前 1 天、6 天和 6 个月后接受 MRI 检查。使用动态稳态自由进动序列分析在摄入 500 毫升水后胃动力，时间分辨率为 0.86 秒。还重复采集轴向图像堆栈以确定随时间变化的胃内液体量。
6 个月后平均超重体重指数损失 60.6%。动态分析显示，LSG 后和随访期间，胃窦推进性蠕动得以保留，但折叠速度从 LSG 前的 2.7 mm/s 显著增加到 6 个月后的 4.4 mm/s。在 3 名患者中，套管本身没有可识别的蠕动，而在另外 2 名患者中，套管仅表现出不协调或被动运动。因此，套管内的液体输送明显延迟，而胃窦显示出加速推进，排空半衰期从术前 16.5 分钟缩短到术后 6 个月的 7.9 分钟。
由于 LSG 手术，胃在功能上被分为无推进蠕动的套管和加速的胃窦。加速排空似乎是由更快的蠕动折叠引起的。
