Computer simulation of the impact of different dimensions of the stomach on the validity of electrogastrograms

Gastric Measurement

DOI: 10.1007/BF02522850

Cite this article as:
Mintchev, M.P. & Bowes, K.L. Med. Biol. Eng. Comput. (1998) 36: 7. doi:10.1007/BF02522850

Abstract

The impact of the dimensions of the stomach on cutaneous recordings of gastric electrical activity (GEA) has not been adequately studied. The stomach was represented as a truncated conoid in a spherical coordinate system. The gastric electric field was modelled using a previously described methodology. Electrical potentials were calculated from sets of points simulating standard cutaneous recordings. The frequency of the signals was maintained at 3 cycles min−1 (period of repetition: 20s), while the velocity of propagation of the depolarisation waves was reduced relative to the reduction in gastric dimensions. The signals were digitally contaminated with a random artificial artefact with a constant amplitude range of 0.2 mV, while the dimensions of the conoid (the circumferential radii and the length of the central axis) were decreased by factors of 1.5, two, four, six and eight. Simulated EGG signals were evaluated quantitatively. Simulated EGG records contaminated with random signals recorded from stomachs with decreasing dimensions exhibited non-linearly increasing standard deviations (p<0.001). Randomly contaminated EGGs calculated from stomachs with dimensions reduced four, six and eight times were abnormal according to previously established quantitative criteria. Computer modelling indicated that gastric dimensions can significantly influence the validity of EGGs. These findings could be particularly important in a paediatric electrogastrography.

Keywords

Electrogastrography Validity Computer modelling 

List of abbreviations

EGG

electrogastrography, electrogastrogram

ECG

electrocardiography, electrocardiogram

FHT

fast Hartley transform

GEA

gastric electrical activity

MF

mean frequency

pdf

probability density function

SD

standard deviation

T-F

time-frequency

cpm

cycles min−1

Copyright information

© IFMBE 1998

Authors and Affiliations

  1. 1.Department of SurgeryUniversity of AlbertaEdmonton
  2. 2.Department of Electrical EngineeringUniversity of CalgaryCanada

Personalised recommendations