that has been demonstrated in numerous studies to exactly correspond to simultaneous recordings of the mucosa or serosa. Since it is much easier to perform, the cutaneous electrogastrography has been used most frequently. Several EGG signals may be recorded from various standardized positions on the abdominal wall, However for maximal accuracy and analysis it is important to select the one channel with the highest amplitude. Each channel usually consists of three Ag-AgCl electrodes. Recordings are made both fasting (usually 10-30 minutes) and after a stimulation meal (usually 30-60 minutes) with the patient lying quietly. The stimulation meal may vary but the most commonly used medium is room temperature water. Deviations from the normal frequency may be referred to as alterations in the gastric myoelectrical activity (GMA) or intestinal myoelectrical activity(IMA), These include: 1) bradygastria GMA, 2) tachygastria GMA, or 3) 3 cycle per minute hypernormal GMA or hyponormal GMA . In normal individuals the power of the electrical signals increases after the meal. In patients with abnormalities of stomach and/or gastrointestinal motility, the rhythm often is irregular or there is no post-stimulation meal increase in electrical power. Bradygastria, normogastria and tachygastria Terms bradygastria and tachygastria are used at the description of deviations of frequency of an electric signal from slow waves are initiated by pacemaker in the stomach from normal frequency of 3 cycles per minute. A bradygastria is defined, as decreased rate of myoelectrical activity in the stomach, as less than 2.5 cycles per minute for at least 1 minute. A tachygastria is defined, as increased rate of myoelectrical activity in the stomach, as more than 3.75 cycles per minute for at least 1 minute. A bradygastria and tachygastria may be associated with nausea, gastroparesis, irritable bowel syndrome, and functional dyspepsia. CPT and HCPCS codes for electrogastrography There are following Current Procedural Terminology (CPT) and Healthcare Common Procedure Coding System (HCPCS) codes (maintained by the American Medical Association) for cutaneous electrogastrography: Electrogastroenterography An electrogastroenterography (EGEG) is based that different organs of a GI tract give different frequency slow wave. EGEG electrodes are as much as possible removed from a stomach and an intestines—usually three electrodes are placed on the extremities. It allows to receive stabler and comparable results. Computer analysis An electrogastroenterography analysis program calculate P(i) – capacities of an electric signal separately from each of organ of GI tract in corresponding range of frequencies: where S(n) – spectral