title: Assessment of the post-prandial distribution of intragastric contents using an automated technique.
abstract: The distribution of intragastric contents has been studied using operator-dependent methods. We devised an automated technique for determining post-prandial intragastric distribution of radiolabeled meals, based on the calculation of the 'center of activity' (CA) of the radioactivity contained in the stomach in any given scintigraphic image. Twelve healthy volunteers and eleven functional dyspepsia (FD) patients ingested a liquid meal (320 mL, 450 kcal) labeled with (99m)Technetium-phytate. Images of the stomach were acquired every 5-10 min for 2 h, and counted to determine the percentage of total activity retained in the upper half of the stomach, as visually delineated. Each image was then processed using an algorithm for calculating a CA value representing the average of image-forming points corrected by pixel number. The relative CA position along the main longitudinal axis of the stomach, as defined by a digital 'skeletonizing' process, was expressed in a '0 to 1' scale. In the FD patients, the average of all CA determinations was significantly higher than in the controls (0.56, 0.30-0.80 versus 0.48, 0.33-0.68, p < 0.05) and correlated significantly with proximal stomach retention values assessed by a visual method (R = -0.64, p < 0.001). Assessing post-prandial intragastric distribution by a novel automated method is feasible and yields reliable data, while being much less operator dependent.
authors.affiliation: Departamento de Física e Matemática, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, SP 14040-901, Brazil.
authors.forename: Eder R
authors.initials: ER
authors.lastname: Moraes
authors.forename: Luiz E A
authors.initials: LE
authors.lastname: Troncon
authors.forename: José Ruver L
authors.initials: JR
authors.lastname: Herculano
authors.forename: Marie
authors.initials: M
authors.lastname: Secaf
authors.forename: Ricardo B
authors.initials: RB
authors.lastname: Oliveira
authors.forename: Oswaldo
authors.initials: O
authors.lastname: Baffa
mesh_terms: D000328:Adult; D000465:Algorithms; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005766:Gastrointestinal Contents / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D010833:Phytic Acid / Q000493:pharmacokinetics; D049268:Positron-Emission Tomography / Q000379:methods; D019518:Postprandial Period / Q000502:physiology*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D013270:Stomach / Q000000981:diagnostic imaging* / Q000502:physiology*
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C026177:technetium phytate; D010833:Phytic Acid