Abstract
Impaired fundic accommodation (FA) limits fundic relaxation and ability to act as a reservoir for food. Assessing intragastric meal distribution (IMD) during gastric emptying scintigraphy (GES) allows for a simple measure of FA. Goals: 1) Evaluate nuclear medicine and radiology physician trained readers’ visual assessment of FA from solid-meal GES; 2) Develop software to quantify GES intragastric meal distribution (IMD); 3) Correlate symptoms of gastroparesis with IMD and GE. Methods: After training to achieve consensus interpretation of GES FA, 4 readers interpreted FA in 148 GES studies from normal volunteers and patients. Mixture distribution and Kappa agreement analysis assessed reader consistency and agreement of scoring of FA. Semi-automated software quantified IMD (ratio of gastric counts in the proximal stomach to total stomach) at 0, 1, 2, 4 hrs postprandially. ROC analysis was performed to optimize diagnosis of abnormal IMD0 (IMD at 0 min) with impaired FA. IMD0, GES, water loading test and symptoms were then compared in 177 patients with symptoms of gastroparesis. Results: Reader pairwise weighted Kappas visual assessment of FA averaged 0.43 (moderate agreement) for normal vs impaired FA. Readers achieved 84.0 % consensus and 85.8% reproducibility in assessing impaired FA. IMD0 based on division of the stomach into proximal and distal halves averaged 0.809±0.083 (SD) for normal FA compared to 0.447±0.132 (p<0.01) for impaired FA. Optimal cutoff for IMD0 based on ROC analysis was 0.568 to discriminate normal versus impaired FA (sensitivity 86.7%, specificity 91.7%). Of 177 patients with symptoms of gastroparesis, 129 (72.9%) had delayed GE; 25 (14.1%) had abnormal IMD0. Low IMD0 (impaired FA) was associated with increased early satiety (P = 0.02). Conclusion: FA can be assessed visually during routine GES with moderate agreement and high reader consistency. Visual and quantitative assessment of FA during GES can yield additional information on gastric motility to help explain patient symptoms.
- Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.