1. Introduction

Biofeedback has its application in gastroenterology as well. According to the definition of biofeedback indicated by Webster Dictionary," the technique of making unconscious or involuntary bodily processes (such as heartbeats or brain waves) perceptible to the senses (as by the use of an oscilloscope) in order to manipulate them by conscious mental control," few people would expect

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and eproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

the application of feedback in the gastrointestinal tract. If you look to the well-known French dictionary Larousse, one cannot easily understand the use of biofeedback by gastroenterologists:" Méthode de rééducation utilisant l'action du système nerveux sur les réactions physiologiques "(Method for reducation using the action of the nervous system on physiological recations). To our disappointment, the explicatory dictionary of our tongue mother, Romanian, simply ignores the word biofeedback, maximum it offers is only "feedback." According to these definitions, nonspecialists could believe that biofeedback is something for the patients with disorders of the nervous system. However, the gastrointestinal tract has its own nervous system as well, thus biofeedback should work also for the gastrointestinal system.

2. Technique of anorectal biofeedback

Figure 1. Laboratory for anorectal manometry and biofeedback.

Figure 2. Balloon used for anorectal biofeedback.

resolution device.

The performance of anorectal biofeedback requires the availability of a manometry laboratory [1, 9]. Figure 1 displays a room for gastrointestinal manometry which is useful also for anorectal anometry and biofeedback. The equipment needed for biofeedback is any good

Factors Predicting Failure in Anorectal Biofeedback http://dx.doi.org/10.5772/intechopen.76374 23

We started the procedure with water-perfused systems, using balloons. The balloons were inflated during the procedure and following anorectal manometry, asking the patient to expel the balloon. The patients were also looking to the screen to observe the pressure variations on the screen. Figure 2 shows the catheter and the balloon used for biofeedback. More recently, after finishing the investigations described here, we started working with a solid-state high-

The investigation of the anorectal function in patients with defecation disorders should be carried out in a dedicated room of the laboratory for gastrointestinal motility studies in conditions of

system of standard anorectal manometry or of high-resolution manometry (HRM).

Which is the segment of the gastrointestinal tract best suitable for the application of biofeedback? This is the anorectal segment, having important innervation and requiring a perfect correlation between the contraction and relaxation of its different components during defecation [1]. Defecation is a complex function and its deterioration may have very important impact on the quality of life of any patient with defecation disorders [2]. The application of the biofeedback for the correction of defecation disorders caused by the impairment of the anorectal segment of the digestive tract is called anorectal biofeedback.

The physiological signal triggering the biofeedback activity is represented by the pressure of the anorectum in relaxation and contraction. Thus, anorectal biofeedback relies on anorectal manometry. One can claim that anorectal biofeedback represents the field where anorectal manometry evolves from the diagnostic role to the therapeutic role [3]. The clinical conditions where anorectal biofeedback based on anorectal manometry is useful are represented by defecation disorders: anal incontinence and terminal constipation. Both may become severe conditions deteriorating the quality of life [4–7].

The anatomical and physiological background of the normal defecation relies on the integrity of the anorectal structure and function, and these may be influenced by general or systemic conditions or by local changes [8]. The retentions of the fecal bolus are a complex mechanism that involves the two anal sphincters as well as the 90 anorectal flexure. During defecation, the external anal sphincter is relaxing, the puborectal muscle is relaxing as well, and this leads to changes of the anorectal angle to 140; meanwhile, the abdominal wall muscles contract to increase the intraabdominal pressure. The anal canal is situated in the thickness of the perineum. Posterior to the anus are found in the levator ani muscles and laterally the ischioanal fossa is found. The anatomical relations of the anterior aspect of the anus are different in women and men. In woman, we found the vagina and in men the prostate.

The internal structure of the anal canal is covered by a mucosa formed from simple epithelium. At this level are present the vertical folds that form the anal columns. The inferior third of anal canal is covered by a stratified squamous epithelium that is continuous with the perineal skin. The external anal sphincter is formed from three circular striated muscles the surround the anal canal. The internal anal sphincter lies directly superiorly to the external sphincter. While the control of the external sphincter is voluntary, the internal one is controlled entirely involuntary. The innervations of the sphincter apparatus are realized through fibers from the lumbosacral plexus.
