Is anorectal endosonography valuable in dyschesia?

Abstract

Aims: Dyschesia can be provoked by inappropriate defecation movements. The aim of this prospective study was to demonstrate dysfunction of the anal sphincter and/or the musculus (m.) puborectalis in patients with dyschesia using anorectal endosonography. Methods: Twenty consecutive patients with a medical history of dyschesia and a control group of 20 healthy subjects underwent linear anorectal endosonography (Toshiba models IUV 5060 and PVL-625 RT). In both groups, the dimensions of the anal sphincter and the m. puborectalis were measured at rest, and during voluntary squeezing and straining. Statistical analysis was performed within and between the two groups. Results: The anal sphincter became paradoxically shorter and/or thicker during straining (versus the resting state) in 85% of patients but in only 35% of control subjects. Changes in sphincter length were statistically significantly different (p<0.01, χ 2 test) in patients compared with control subjects. The m. puborectalis became paradoxically shorter and/or thicker during straining in 80% of patients but in only 30% of controls. Both the changes in length and thickness of the m. puborectalis were significantly different (p<0.01, χ 2 test) in patients versus control subjects. Conclusions: Linear anorectal endosonography demonstrated incomplete or even absent relaxation of the anal sphincter and the m. puborectalis during a defecation movement in the majority of our patients with dyschesia. This study highlights the value of this elegant ultrasonographic technique in the diagnosis of "pelvic floor dyssynergia" or "anismus". C onstipation is one of the most common gastrointestinal problems in Western Europe. Among other criteria, constipation is defined as less than three bowel movements per week for at least 12 weeks over one year.1 Dyschesia is an entity characterised mainly by difficult evacuation of stools, forced straining during defecation, and a sensation of incomplete evacuation after defecation. Although not specific for dyssynergia, a need for manual disimpaction or support of the pelvic floor can exist during defecation. Defecation frequency can be normal.The aetiology of dyschesia can be divided into two groups. Organic aetiological factors (tumours, etc.) need to be differentiated from functional disorders. The most prevalent functional cause of dyschesia is pelvic floor dyssynergia where the patient does not sufficiently relax and sometimes even paradoxically contracts the pelvic floor muscles (anal sphincter and musculus (m.) puborectalis) during straining to defecate. 2-8To demonstrate insufficient relaxation of the anal sphincter and m. puborectalis during defecation, a manometric and/or electromyographic study of these pelvic floor muscles can be performed.Anorectal endosonography was introduced by John Wild in 1949. 9 The technique has continuously been improved since then. Flexible as well as rigid echoprobes can now be used to visualise the rectal wall and other pelvic floor structures. Two types of acoustic windows are used. Accurate...

Dynamic MR assessment of the anorectal angle and puborectalis muscle in pediatric patients with anismus: Technique and feasibility

“…The preliminary results of the present study indicate that any radiological evidence of paradoxical contraction of the pelvic-floor muscle and acute angulation of the anorectal angle during straining identified by dynamic MRI in the supine position would suffice to differentiate normal from abnormal defecation dynamics. It is noteworthy that ARM and anorectal endosonography also require the patient to adopt a leftlateral position (1,18,22).…”

Is dynamic two-dimensional anal ultrasonography useful in the assessment of anismus? A comparison with manometry

“…In an assessment of patients with anismus, Van Outryve et al (29) used linear transrectal sonography to measure muscle length and thickness at rest and during straining and found statistically significant differences. Brusciano et al (7) used 2-D endosonography to identify anismus in patients with obstructed defecation and concluded that during straining differences of less than 0.5 cm between the internal border of the PR and the transducer are suggestive of anismus.…”

“…Once identified and quantified, anatomical and functional changes can be correlated with clinical symptoms and proctological findings (6) . Defecography, manometry, electromyography and, more recently, dynamic magnetic resonance scanning and dynamic anorectal ultrasonography, have all been used to diagnose patients with pelvic floor dysfunctions (1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,20,21,22,23,24,26,27,28,29,30) . Advances in ultrasound technology includes the development of the three-dimensional (3D) anorectal transducer and allows to clearly visualize the anatomic configuration of the anal canal in multiplane images (27) but the twodimensional (2D) ultrasound can be useful in the diagnosis of anorectal disease (7,10,24) .…”

“…It is characterized by symptoms of obstructed defecation associated with paradoxical contraction of the pelvic floor muscles (25) . Dynamic endosonography has become an important diagnostic tool in anismus patients as it allows to visualize the anal sphincters both at rest and during straining (1,2,7,20,21,22,23,24,29) . Recently, Murad-Regadas et al (23) described a novel technique for the assessment of anismus using dynamic two-dimensional anal ultrasonography (2D-DAUS) with satisfactory results when compared to dynamic threedimensional anal ultrasonography (3D-DAUS).…”

Ecodefecografia tridimensional dinâmica: nova técnica para avaliação da Síndrome da Defecação Obstruída (SDO)

“…Tem sido demonstrada a aplicação da ultrasonografia dinâmica [9][10][11][12] e a ressonância nuclear magnética dinâmica [13][14][15] na avaliação da Síndrome da Defecação Obstruída (SDO), com resultados bastante satisfatórios. As técnicas desenvolvidas com a ultrasonografia dinâmica utilizam tipos diferentes de transdutores.…”