Endoanal ultrasound

Role of tridimensional endoanal ultrasound (3D-EAUS) in the preoperative assessment of perianal sepsis

PURPOSE

The aim of this study was to evaluate the accuracy of tridimensional endoanal ultrasound (3D-EAUS) in the diagnosis of perianal sepsis comparing the results with the surgical findings, considered as reference standard.

METHODS

From January 2009 to January 2013, all the patients referred for the assessment and treatment of perianal sepsis with suspected anorectal origin were enrolled in the study. All patients gave informed written consent. Prior to surgery, all the patients underwent anamnestic evaluation, clinical examination, and unenhanced and H2O2-enhanced 3D-EAUS. Surgery was performed by a colorectal surgeon blinded to the 3D-EAUS results.

RESULTS

A total of 212 patients with suspected perianal suppurations were assessed during the study period. In 12 patients, the H2O2-enhanced 3D-EAUS was not performed, and so, they were excluded from the study. Very good agreement between 3D-EAUS and examination under anesthesia (EUA) in the classification of primary fistula tracts (kappa = 0.93) and in the identification of fistula internal opening (kappa = 0.97) was found. There was a good concordance (kappa = 0.71) between 3D-EAUS and surgery in the detection of fistula secondary extensions. The overall sensitivity and specificity of 3D-EAUS in the diagnosis of perianal sepsis were 98.3 and 91.3% respectively.

CONCLUSION

3D-EAUS is a safe and reliable technique in the assessment of perianal sepsis. It may assist the surgeon in delineating the fistula tract anatomy and in determining the origin of sepsis, supporting the preoperative planning of definitive and appropriate surgical therapy.

Anorectal anatomy and imaging techniques

The rectum and anus are two anatomically complex organs with diverse pathologies. This article reviews the basic anatomy of the rectum and anus. In addition, it addresses the current radiographic techniques used to evaluate these structures, specifically ultrasound, magnetic resonance imaging, and defecography.

Incidence and clinical outcomes of intersphincteric abscesses diagnosed by anal ultrasonography in patients with crohn's disease

BACKGROUND

Intersphincteric abscesses have been reported as uncommon manifestations of perianal Crohn's disease (CD) in surgical series, and may be diagnosed earlier by means of anal ultrasonography. The aim of this study was to evaluate the incidence and outcomes of intersphincteric abscess in a prospective cohort of patients with CD referred for perianal symptoms.

METHODS

Of the 420 patients with CD attending our outpatient clinic over a period of 5 years, 55 (31 males, mean age 38 ± 13 years) underwent anal ultrasonography because of newly developed symptoms suggesting perianal disease; a clinical evaluation and perianal examination was performed on the same day.

RESULTS

An intersphincteric abscess was diagnosed in 23 (42%) of the 55 patients with perianal symptoms, for a total cumulative 5-year incidence of 5% (95% confidence interval [CI]: 3%-7%). During a median follow-up period of 23 months (range 6-53), four of these patients required surgery, four developed a perianal fistula or small ischiorectal abscess not requiring surgery, and 15 experienced a benign course. The patients with a benign course had a longer duration of CD at the time of onset of the perianal symptoms.

CONCLUSIONS

Intersphincteric abscesses frequently cause perianal symptoms in patients with CD, and their clinical outcomes vary from rapidly progressive inflammation to a benign self-limiting course. The favorable outcome observed in some patients supports a first-line conservative approach to the condition.

Radiologic evaluation of pelvic floor disorders

Several imaging modalities are available ranging from fluoroscopic techniques to ultrasonography and MRI for the evaluation of patients with pelvic floors disorders. High-resolution ultrasonography and MRI not only provide superior delineation of the pelvic floor anatomy but also reveal pathology and functional changes. This article focuses on standard imaging procedures including defecography, ultrasonography, and MRI and discusses its use in clinical practice by illustrating both normal and abnormal patterns.

Transperineal three-dimensional ultrasound in evaluating anal sphincter muscles

OBJECTIVES

To evaluate whether transperineal three-dimensional (3D) ultrasound can be used to depict normal anal sphincter anatomy and to measure the thickness of muscle layers and the anteroposterior length of the levator hiatus.

METHODS

The study included 22 normal nulliparous female volunteers. Transperineal 3D sonographic evaluation of the anal canal included assessment of sphincter shape, echogenicity, marginal definition and muscle thickness. Measurements of the thickness of the internal anal sphincter (IAS) and puborectalis muscle (PRM) were determined with the women at rest and during squeezing by two observers, and interobserver reliability was determined. The anteroposterior length of the levator hiatus at rest and during squeezing was measured.

RESULTS

The proximal end of the anal canal (towards the rectum) consisted of overlapping IAS and PRM, and the distal end (towards the anus) consisted of overlapping IAS and external anal sphincter (EAS). At the PRM level, the mean +/- SD IAS thickness was 2.3 +/- 0.5 mm at rest and 2.5 +/- 0.4 mm during squeezing, and at the mid-EAS level it was 2.9 +/- 0.5 mm at rest and 2.8 +/- 0.5 mm during squeezing. The PRM thickness was 6.5 +/- 1.0 mm at rest and 6.4 +/- 1.2 mm during squeezing. The difference in muscle thickness of the sphincter layers with the woman at rest and during squeezing was not significant. The anteroposterior length of the levator hiatus was 51.7 +/- 5.0 mm at rest and 47.4 +/- 4.1 mm during squeezing (P < 0.01).

CONCLUSION

Transperineal 3D ultrasound may be useful in evaluating the anatomy of the anal canal.

Posterior pelvic floor disorders: a prospective comparison using introital ultrasound and colpocystodefecography

OBJECTIVE

To compare introital ultrasound with colpocystodefecography (CCD) in quantifying the anorectal angle and in the diagnosis of posterior pelvic floor disorders.

METHODS

Forty-three consecutive women with functional impairment of the posterior pelvic floor were enrolled after a clinical evaluation. Using both CCD and introital ultrasound examination, the anorectal angle was measured during squeezing to evaluate the strength of voluntary muscle contraction and during straining to assess pelvic floor relaxation. Rectocele depth and the presence of intussusception were assessed. The performance of CCD and that of introital ultrasound were compared.

RESULTS

Good concordance was obtained between introital ultrasound and CCD. The intraclass correlation coefficient was 0.82 (95% CI, 0.69-0.89) for measurement of the anorectal angle during squeezing and 0.67 (95% CI, 0.47-0.81) during straining. Rectoceles > 4 cm on CCD were detected by introital ultrasound in 100% of cases, and there was 91% agreement for rectal intussusception. Cohen's kappa index was moderate for rectocele assessment (0.41, P < 0.01) and excellent for intussusception (0.91, P < 0.001). It was also noted that introital ultrasound could be used to detect pelvic floor dyssynergia.

CONCLUSIONS

Introital ultrasound is a simple, accurate, non-invasive method with which to assess anorectal dynamics.

[Descending perineum in women]

Physiopathological and clinical interpretation of the descending perineum as described by A. Parks in 1970 remains difficult. This review is based on the literature between 1966 and 2004. The observed symptoms are more often due to associated lesions. The descending perineum on X-ray is not always symptomatic. Colpocystography shows the descent of the perineum and pelvic disorders from the anterior and middle parts of the perineum whereas defecography seems to provide a better diagnosis of dyschesia due to posterior damage (such as rectocele or endo-anal intussusception). The first step of treatment is reeducation and medical treatment because there is no consensus for surgical therapy. Soft sacrocolpopexy by the abdominal approach with three meshes, one under the bladder, one in front of and one behind the rectum can be proposed for complete descending perineum. Transanal rectal resection by staple could be useful when the descending perineum is only associated with a rectocele and/or an intra-anal intussusception.

The use of intra-operative endo-anal ultrasound in perianal disease

INTRODUCTION

Endoanal ultrasound (EAUS) has demonstrated high sensitivity and specificity for the structural imaging of anorectal pathology. This study prospectively assessed the impact of intra-operative EAUS on the surgical management of perianal disease.

METHODS

EAUS was performed prior to and after examination under anaesthesia (EUA) in a consecutive series of patients with perianal disease. The impact of EAUS on the surgery performed was identified.

RESULTS

Forty-three procedures have been performed in 38 patients (21 male, 17 female; mean age 42.7 years, range 6-76 years) over a three year period. Pathologies encountered were fistula-in-ano (42%), fissure-in-ano (26%), complicated perianal sepsis (16%) and carcinoma (5%). No specific abnormality was identified in 5 symptomatic patients (12%). Four patients with fissures had undergone previous sphincterotomy. In 22 cases (51.2%) the EAUS findings affected the surgical management (extent of muscle above a fistula 9 cases, extent of sphincterotomy 7 cases, site of sepsis identified 2 cases, exclusion of sepsis 2 cases, assessment of cancer resectability 1 case, biopsy of intersphincteric lesion 1 case).

CONCLUSION

Intra-operative EAUS accurately identifies perianal disease and influences the surgical procedure performed. While not essential, it is a useful adjunct especially in recurrent perianal sepsis, undiagnosed anorectal pain and anal fissure.

Valor actual de la ecografía endoanal en el diagnóstico de la enfermedad proctológica benigna

Endoanal ultrasound is undoubtedly one of the major advances that has taken place in the evaluation of anorectal disease and pelvic floor disorders in the last decade. The main indications for endoanal ultrasound are evaluation of the morphology of the sphincteric apparatus in patients with fecal incontinence, the localization of perianal abscesses and fistulas, the staging of anal cancer and follow-up of squamous cell carcinoma after conservative treatment, and the study and morphological confirmation of lateral internal sphincterotomy in patients with fissure-in-ano, amongst others. In this article we review the main indications and use of endoanal ultrasound in the diagnosis of benign proctological disease.

Updated recommendations on ultrasonography in urogynecology

Ultrasound is a supplementary, indispensable diagnostic procedure in urogynecology; perineal, introital, and endoanal ultrasound are the most recommended techniques. The position and mobility of the bladder neck can be demonstrated. In patients undergoing diagnostic work-up for urge symptoms, ultrasound occasionally demonstrates urethral diverticula, leiomyomas, and cysts in the vaginal wall. These findings will lead to further diagnostic assessment. The same applies to the demonstration of bladder diverticula, foreign bodies in the bladder, and bullous edema. With endoanal ultrasound, different parts of the sphincter ani muscle can be evaluated. Recommendations for the standardized use of urogenital ultrasound are given.

Clinical presentation, imaging, and staging of anal cancer

Perianal symptoms are common, and benign anorectal conditions have clinical features not too dissimilar to those associated with anal canal carcinoma. To avoid delayed diagnosis, physicians need to be cognizant of the possibility of anal canal carcinoma, which can be effectively treated with chemoradiation therapy without the need for mutilating surgery. Appropriate imaging studies should be obtained for accurate staging of the disease and for follow-up examinations after definitive treatment.