1. Introduction.
2. Relevance.
3. Goals and Objectives.
4. The problem at the level of subject area.

4.1 Object of the study.
4.2 Methods of research.
4.3 Electrogastroenterogram.
4.4 Equipment for the study.

Researches of last years reveal the accurate tendency to increase in disease of digestive organs. In this connection there was an absolute must of constant improvement of available methods of diagnostics and also creation and working out of the new, earlier not used methods, to detect the disease in its early stages, to assess the extent of lesions, to supervise results of spent therapy.
Electrogastrogram: An electrogastrogram (EGG) is a graphic produced by an electrogastrograph, which records the electrical signals that travel through the stomach muscles and control the muscles' contractions. An electrogastroenterogram (or gastroenterogram) is a same procedure, at which write down electric signals not only from a stomach, but also from intestines.

These names are made of different parts: electro, because it is related to electrical activity, gastro, Greek for stomach, entero, Greek for intestines, gram, a Greek root meaning "to write".[12]

Electrogastrogram non-invasive, has no contraindications and is well tolerated by all patients. This allows examining even extremely heavy patients, both before the operation, and in the first hours of the postoperative period. Considering simplicity and availability of the methodology can be repeated numerous studies to assess the dynamics of the treatment process. Data obtained with electrogastrogram not contradict, and often are ahead of the results of X-ray and endoscopic studies, which showed a high sensitivity method for the diagnosis of motor disorders.

The aim of this work is to improve the timeliness and accuracy of diagnosis of diseases of gastrointestinal tract through the establishment of a moderns algorithms of processing electrogastroenterography signal.

To achieve the goal, it is necessary to solve such problems:

1.  Develop the technical means of registration electrogastroenterography signal;
2.  Develop a model electrogastroenterography signal for each of the gastrointestinal tract;
3.  Develop algorithms for determining the diseases of the gastrointestinal tract;
4.  Develop software implementing established models and algorithms.

To better understand how and why developing various diseases of the digestive system, must first understand its structure. Simplified description of the gastrointestinal tract:[11]

1. Esophagus: it is a long tube of muscle tissue in which the food moves from mouth to stomach.
2. Abdominal cavity below the diaphragm. Here are all the abdominal organs.
3. Stomach is in the upper abdomen. Here the food exposed to gastric juice and enzymes produced by gastric mucosa. Elements of food that are crushed to smaller components.
4. Esophageal sphincter:the valve which prevents the release of food mixed with acid back into the esophagus.
5. Porter : a small circular muscle at the outlet of the stomach. Controls the flow of food in the masses of the stomach small intestine (duodenum).
6. Small intestine the most important digestive organ man. The total length of small bowel adult 4.5-6 meters. In the small intestine are absorbed proteins, fats, carbohydrates, vitamins, minerals. Adopted by the department to allocate the three small bowel: duodenum (duodenum), jejunum (jejunum), iliac intestine (ileum).
7. В In the duodenal food delivered from the stomach, mixed with bile and pancreatic enzymes. Here is absorbed iron and calcium.
8. В In jejunum absorbed a large part of the food items. Jejunum from the inside is covered with a huge number of villi - thin tubes that increase the suction surface of the bowel. Chyme (food mass) is moving here in liquid form. Proteins, fats and carbohydrates from the villi and are absorbed through the bowel wall into the bloodstream.
9.  The last segment of small bowel: iliac intestine. Here comes the absorption lip soluble vitamins A, D, E, K, and other nutrients.
10. Ileotsekalny valve divides thin and thick intestines. Valve chyme passes from the small bowel to fat and prevents a return throw from the seed masses of bacteria in the large intestine almost sterile thin.
11. В In the large intestine of chyme arriving from the small bowel, gradually draw off the water and, thus, formed stools. Large intestine is home to huge quantities of bacteria (Escherichia coli, bifid bacteria, lacto bacteria), which are involved in the process of digestion.

Figure 1. General scheme of the digestive system of man.

Promotion of food to the digestive tract, the mechanical treatment, mixing with digestive juices is one of the important functions of the gastrointestinal tract. Doctors called the motor-function evacuative.

Food ball when swallowing esophagus comes in under the pressure and moving it through a rhythmic wave of reductions. Then, passing the esophageal-gastric passage (it is also called the lower esophageal sphincter), it enters the stomach.

In the stomach the food is mixed with a bundle of digestive juices and is machined through the peristaltic short cuts and slow long-term changes in tone. Upon completion of processing in the stomach the food in small portions with a period of about 20 seconds goes to the duodenum, where its further processing enzymes allocated pancreas and gall. And its movement is provided by peristaltic undulating cuts.

Then the food Became the original pulp, chyme, enters the jejunum further in iliac intestine where further digestion and absorption of nutrients. Further it is the way into the colon. Here, food is delayed a long time - up to 20 hours. There are three types of motor activity of colon cancer: a direct displacement of the mass, retrograde (reverse) to promote and rhythmic reductions in individual segments of intestine. Such complex behavior is fully intestine absorption of salt and water from the stool and regular bowel movement.

It is the coordinated work of the esophagus, stomach and intestine ensures proper digestion and that its coordination disorder underlie or are a consequence of many diseases of the digestive tract. And that is why on the motor-function evacuative need to know everything.

Currently, there are two groups of study motor-evacuative function gastrointestinal tract(GIT).

The first group includes methods to record contractile activity GIT by measuring the pressure inside of a division GIT using cylinders micro detector, radio pill open water perfusion catheters. Unfortunately, the introduction of a foreign body, which is any of the above sensors, resulting in irritation and body changes its motor activity.

The second group includes electrophysiological methods based on the relationship of electricity and refractive activity GIT. They include a registration biopotentsial to fixed on the walls of the electrodes, the so-called direct electrogastroenterogram or register biopotentsial with skin electrodes, fixed to the abdomen or extremities - an indirect or peripheral electrogastroenterogram.

Naturally, the need for implantation of electrodes limits the use of direct electrogastroenterogram in clinical practice. Peripheral electrogastroenterogram being not invasive, does not require any intrusion into the human body, is well tolerated by all patients. This allows examining even extremely heavy patients before the operation, and in the early hours of the postoperative period.

Electrogastroenterogram: method of study to evaluate the bioelectrical activity of the stomach, duodenum and other divisions GIT. It is based on registration of changes in electrical potential from the GIT. [8]

In the quiescent state of smooth muscle cells, and cells of the heart muscle or skeletal muscle, resting membrane potential are due to concentration gradient of ions across the cell membrane. Periodic changes in membrane potential known as slow waves or transmembrane building peace. A transmembrane potential of resting understand potential difference between intra-and extracellular environment in the absence of changes in electrical activity. The value of transmembrane capacities ranging from 20 to 90 mV. The slow electrical waves are a periodic depolarization and repolarization phases of smooth muscle cell membranes. In the stomach, slow waves are generated miogennym peysmeykerom, located in gastric body. The slow waves occur with a constant for each department GIT frequency. As we have seen a number of researchers in the intestine, there is proximal-distal gradient of frequency of slow waves, the maximum frequency observed in the duodenum and the primary department jejunum rectum, in a distal direction frequency decreases. It is important to note that the frequency of electrical slow wave determines the maximum possible reductions in the frequency of smooth muscles of the gastrointestinal tract. The experiment revealed that out of bioelectrical activity of the digestive gastrointestinal tract is characterized by phases of relative calm and the phases of enhanced activity (starvation peristaltic activity).
The slow waves by themselves do not cause muscle contraction. Reduction of smooth muscle tissue occurs when you are on a plateau of slow waves of fast electrical oscillations, action potentials (AP). Action potentials are a relatively rapid change in membrane potential, which is closely related to the level of capacity at rest and the amplitude of electrical slow waves, and reflect a local decrease in muscle fibers. Single cause tonic decrease in PD, PD group are rhythmic contractions. The strength of reduction of muscle fiber is proportional to the number of DD in the group. The slow wave is created in the muscles of the potential close to the threshold of activation, which enables the emergence of PD with a consequent reduction of muscle fibers. With the lack of depolarization of cell membrane PD fade, with a high depolarization can initiate propagating slow wave. However, some authors believe that the decrease in muscle fiber possible, and in the absence of peak potentials. At the same time recorded minimum in amplitude reduction of ulcer sites, the relevant basic electrical rhythm.The mechanism of generation of electrical slow waves is stable. They are little changed under the influence of acetylcholine, atropine, adrenaline, morphine, histamine, cocaine, nicotine. However, all these substances are definitely affect the appearance of the peak potentials and a reduction in smooth muscle.
In the early 20 th century, the researchers measured the electrical activity of smooth muscle cells. To do this, use as intracellular or extracellular means of allocating the signal. At the present time to determine the bioelectrical activity of the gastrointestinal tract using direct methods with the implanted electrode and indirect methods, based on registration of changes in electrical potential gastro-intestinal tract of the body surface. Direct techniques allow more accurate assessment of the motor-evacuative function of the intestine studied, as it allows to record action potentials. However, invasiveness method imposes some restrictions on its use. Indirect method biopotentsial has several advantages over direct. He no invasive, has no contraindications, a measure bioelectric activity of all divisions GIT. Electrogastroenterogram indirect method allows to register only change the slow waves. However, as mentioned above, slow waves do not cause muscle contraction intestine, resulting in not fully reflect the motor-evacuative activities intestine. Nevertheless, studies have shown that rates of change between the slow waves, and DD has a high correlation. This relationship so close and reliable than the intense peak power and motor activity of the body. With reductions in active and appears to packs DD states and increasing the amplitude of slow waves. Register биоэлектрического building was carried out from the surface of the skin in the stomach. Currently, this method of allocating the signals commonly used in our clinics, as well as abroad. Negative features of this method is the inability to assess the bioelectric activity of various departments GIT.
Thanks to the work of rib VG, a method of peripheral electrogastroenterogram in which the registration signal various divisions GIT made from limbs. The ability of this method is due to constant frequency of smooth muscle cuts in various departments GIT. To register the electrical activity of the various divisions GIT using highly bandwidth amplifiers with low frequency (0 to 1 Hz), with a strengthening of the DC, thus eliminating noise being made in high-frequency signal capacities of other bodies. Scheduled spectrogram, and the digital data obtained after processing the signal level of electrical activity of the stomach and duodenum, iliac, and colon, the rhythm of cuts and coordinating the work of neighboring departments GIT. Frequency reductions GIT various divisions, as was shown in a number of works are stable parameter. The boundaries of these frequency intervals are shown in the table.

Modern instrumentation used for diagnostics and research, provide admission and registration of signals from skin electrodes for a period of 1 hour to 24 hours, as well as storage, processing and document submission of the information obtained. Installed filter device simultaneously to evaluate the electrical activity of gastric, duodenum, jejunum, small intestine, and colon, in the frequency range 0,01-0,25 Hz.

Figure 2. Electrogastroenterograph EGEG-01K

Gastroscan-HEV:

Figure 3. "Gastroscan HEV" - computer-based instrumentation to monitor both pH and electrical activity GIT

Figure 4. Portable apparatus for electrogastroenterogram "Digitrapper EGG".

Next page →
-up-