# Unraveling the Enigma of Post-sleeve Differential Liquid Tolerance: A Time-Resolved MRI Study

## TL;DR

This study uses MRI to show that water and juice tolerance improves six months after sleeve gastrectomy, with changes in stomach motility patterns.

## Contribution

The study introduces time-resolved MRI to analyze post-sleeve gastrectomy fluid tolerance and gastric motility dynamics.

## Key findings

- Water tolerance improved significantly six months after surgery, while juice tolerance remained better.
- MRI showed improved gastric motility, including increased antral contraction height and velocity.
- Early wave contraction height differed significantly between water and juice tolerance.

## Abstract

Laparoscopic sleeve gastrectomy is one of the restrictive bariatric procedures that often impair food and fluid tolerance and negatively impact quality of life as it affects patients’ weight loss, hospital stay, and lifestyle.

The objective of this study was to evaluate water and juice tolerance after LSG using dynamic magnetic resonance imaging (MRI) of the stomach to determine the relationship between fluid tolerance and gastric motility.

The prospective cohort study enrolled 17 adult subjects of both sexes, with a body mass index (BMI) greater than 40 kg/m2 without comorbidities or 35 kg/m2 with comorbidities, who underwent LSG. Patients were monitored for water and juice tolerance, and dynamic MRI imaging for gastric motility patterns was obtained at one and six months postoperatively.

More than half of participants (58.8%) reported difficulty tolerating water, while 5.9% of participants expressed early difficulty tolerating juice. After six months, water tolerance improved significantly. Compared to early dynamic MRI, late MRI gastric motility patterns revealed an improvement trend in the form of a significant decrease in antral frequency and an increase in antral velocity, sleeve transit, and contraction height for both water and juice (p < 0.001). Among patients with improved water tolerance (6 patients), late MRI findings were significantly improved compared to their early MRI findings (p < 0.001). Patients’ early wave contraction height was significantly different between water and juice at early and late imaging (p < 0.001).

Time-resolved gastric MRI is a useful tool to explain the roots of post-LSG differential liquid tolerance. The gastric antrum is the only coordinated and functionally motile part of the gastric sleeve. An overall significantly improved motility pattern trend was achieved by the end of the study, with the increase in antral contraction height being the most consistent component of that trend. Water tolerance improves significantly 6 months after LSG but remains worse than juice tolerance.