Analysis of surface geometry of the human stomach using real-time 3-D ultrasonography in vivo.

The objective of this study was to develop an analytical method to describe the three-dimensional (3-D) geometry of the gastric antrum, gastric fundus and the whole stomach. The Fourier series method was used to simulate the organ surface geometry obtained from a 3-D ultrasound system. Data generated from eight antrums and three whole stomachs, at pressures of approximately 7 cm H(2)O, were used for lumen curvature calculations. The principal curvatures spatial distributions were non-homogeneous in the gastric antrum, gastric fundus and the stomach due to their complex geometry. The maximum longitudinal principal curvature in the antrum, fundus and total stomach were, respectively, 0.460 +/- 0.066, 0.583 +/- 0.087 and 1.123 +/- 0.328, whereas the maximum circumferential curvature were 1.192 +/- 0.090, 3.649 +/- 1.574 and 8.444 +/- 3.424, respectively. The present study provides an analytical tool for characterizing the complex 3-D geometry of an organ-like the human stomach reconstructed by clinical imaging modalities. Providing an average tension for the stomach does not reflect the large variation in tension throughout the stomach wall.