MR Defecography, a Diagnostic Test to Evaluate the Pelvic Floor Motion in Patients with Dyssynergic Defecation after Biofeedback Therapy

Abstract

Background: Dyssynergic defecation is a major cause of chronic functional constipation as a common digestive complaint. We clinically evaluated the effects of biofeedback therapy on the pelvic floor motion indices through magnetic resonance (MR) defecography, quality of life and depression in patients with dyssynergic defecation. Methods: In this clinical trial study, among patients referring to the Colorectal Clinic of Hazrat Rasoul Hospital, 22 subjects were randomly assigned into two equal groups (n= 11) to receive either standard only or biofeedback and standard therapy. Dynamic changes of the pelvic floor were measured by MR defecography. During the simulated defecation, two MR defecography dynamic indices including abnormal anorectal angle change and perineal descent were measured before and after treatment. The effects of biofeedback therapy on patients’ symptoms, quality of life and severity of depression were assessed and compared with the standard therapy. Statistical analysis was carried out using independent _t-test and Mann-Whitney test. Results: Paradox index (p< 0.001), perineal descent index (p< 0.001), depression (p< 0.1), physical function (p< 0.001), vitality (p< 0.001) and role emotion (p< 0.001) significantly improved in the biofeedback therapy group in contrast to the standard therapy SDT group. Conclusion: Biofeedback therapy appears to be effective in improving symptoms of functional constipation and dysfunction of pelvic floor motion as well as patient’s quality of life and depression state. MR defecography is able to show the changes in dynamic indices of the pelvic floor through biofeedback therapy.

Accurate Differentiation of Dyssynergic Defecation Patients from Normal Subjects Based on Abnormal Anorectal Angle in MR Defecography

“…Asking the patients contracting the pelvic floor muscles for 12 s. Then have a rest for12 s. Finally strain, till the occurrence of defecation [11].…”

“…The changes from rest to straining were measured as "(ARA at straining)-(ARA at rest)" [13]. In this measurement, the decline of "ARA" defined as "Paradox Index" [11].…”

“…Hence, the strain could occur more easily and forcefully [21]. In addition if the procedures of MR defecography had been imposed a true sitting position with unusual circumstances that bothers the patients, so this imaging is not taken in a real physiologic defecation condition [22]. For as much as the aim in evaluation of the dysfunction of pelvic floor is getting right diagnosis to plan a suitable treatment [23].…”

“…There laxation of the pelvic floor muscles and opening up of the "ARA" in defecation is a learned response which occurs unconsciously and cannot be influenced by gravity (sitting position) [6,22]. Besides, while the exam was done completely in the same position and condition for all subjects (healthy or patient), MRI could significantly detect healthy from patient subjects by ARA index.…”

“…In patient with dyssynergic pattern, MR defecography can show "ARA" get closed and absence of the pelvic floor descending in defecation as illustrated in (Figure 2). There are rare studies on assessing the value of MR defecography in diagnosing of differentiating "dyssynergic defecation" pattern in patients vice versa healthy subjects [11]. This study aimed at investigating sensitive and specific parameters of MR defecography for identifying patients from healthy subjects.…”