Assessment of fundal accommodation in solid meal gastric emptying scintigraphy: a retrospective analysis

AIM: To investigate the feasibility of both quantitative and qualitative assessment of fundal accommodation during solid meal gastric emptying (SGE) scintigraphy. METHODS: SGE scintigraphy studies of 72 patients were retrospectively evaluated. Regions of interest (ROIs) were generated on the stomach at different times (0, 30 min, 1, 2, 3, and 4 h), and the corresponding retention percentages were calculated. Counts as geometric means from anterior and posterior ROIs over proximal stomach half and whole stomach at zero-time were used to calculate gastric fundal accommodation ratio (FAR). The radioactivity at the fundus was visually assessed at zero-time image to generate a four-point fundal accommodation visual score (1 = abnormal, 2 = probably abnormal, 3 = probably normal, and 4 = normal). RESULTS: Fifty patients had normal SGE, and 22 had delayed SGE. The mean FAR was 0.753 ± 0.151. The fundal accommodation visual score and the FAR were significantly moderately correlated (ρ = 0.455, P < 0.0001). Receiver operating characteristic curve analysis revealed a FAR cut-off value of 0.669 distinguishing normal from abnormal FAR (area under the curve = 0.873; P < 0.001) with 70% sensitivity and 92.3% specificity. A comparison of the fundal accommodation visual score and FAR revealed highly significant agreement (P < 0.0001). CONCLUSION: A fundal radioactivity to total stomach ratio of 0.669 at zero-time image was an appropriate threshold for detecting abnormal fundal accommodation. Given the high correlation between visual scoring and quantitative ratios, visual assessment may be regarded as a quick and dependable way to evaluate fundal accommodation.