Transperineal versus hydrogen peroxide-enhanced endoanal ultrasonography in never operated and recurrent cryptogenic fistula-in-ano: a pilot study

Current imaging techniques for evaluation of fistula in ano: a review

Background

Fistula in ano is one of the common anorectal disorders which have a tendency to recur specially in complex cases usually due to missed or undetected sepsis at the time of examination or surgery. A correct identification of the primary source of crypt infection along with a complete understanding of the anatomical course of primary and secondary tracks and abscesses is a prerequisite for the successful management of fistula. Preoperative evaluation of fistula in ano using radio-imaging techniques provides a handy insight of fistula anatomy and helps in planning the appropriate treatment strategy. The objective of this article is to review the role of different radio-imaging techniques in the diagnosis and evaluation of fistula in ano along with their advantages and disadvantages over one another.

Main text

A comprehensive literature review was performed searching through the electronic databases as well as the standard textbooks of colorectal surgery. X-rays (plain radiographs and contrast fistulography), computed tomography (CT) scanning, anal endosonography, and magnetic resonance (MR) imaging are the modalities used for preoperative imaging of fistula in ano. Due to low accuracy, X-ray fistulography is not used now for fistula imaging. CT fistulography can be more accurate in cases associated with acute inflammations and abscesses and the fistulas related with inflammatory bowel disease. Anal endosonography and MRI are two of the mostly used and reliable imaging techniques for fistula in ano. Though the use of a 3D technology has improved the accuracy of anal endosonography, MRI is the preferred choice by many. However, various reports have depicted comparable accuracies for both MRI and anal endosonography showing both to be equally sensitive but MRI to be more specific. 3D endoanal ultrasound, on the other hand, is more rapid and can also be used intraoperatively to provide live imaging during surgical exploration.

Conclusion

Complex and recurrent fistula cases should undergo a preoperative imaging to reduce the chances of recurrence. MRI is recommended as the imaging modality of choice for such cases. 3D anal endosonography may however be a good option over MRI owing to its rapidity, availability, and potential of intraoperative assistance during surgery.

Advances in Perianal Disease Associated with Crohn's Disease-Evolving Approaches

Perianal diseases, common complications of Crohn's disease, are difficult to diagnose/manage. Patients with perianal Crohn's disease suffer from persistent pain and drainage, recurrent perianal sepsis, impaired quality of life, and financial burden. Conventional medical and surgical therapies carry risk of infection, myelosuppression, incontinence, disease recurrence. Although the phenotype of Crohn's disease has been extensively studied, reported outcomes are inconsistent. Endoanal ultrasonography is also becoming popular because of low cost and ability to acquire images in real time. Emerging management strategies for treatment including laser therapy, local injection of agents, use of hyperbaric oxygen, and stem cell therapy, have demonstrated efficacy.

Anoperineal lesions in Crohn's disease: French recommendations for clinical practice

BACKGROUND

Anoperineal lesion (APL) occurrence is a significant event in the evolution of Crohn's disease (CD). Management should involve a multidisciplinary approach combining the knowledge of the gastroenterologist, the colorectal surgeon and the radiologist who have appropriate experience in this area. Given the low level of evidence of available medical and surgical strategies, the aim of this work was to establish a French expert consensus on management of anal Crohn's disease. These recommendations were led under the aegis of the Société Nationale Française de Colo-Proctologie (SNFCP). They report a consensus on the management of perianal Crohn's disease lesions, including fistulas, ulceration and anorectal stenosis and propose an appropriate treatment strategy, as well as sphincter-preserving and multidisciplinary management.

METHODOLOGY

A panel of French gastroenterologists and colorectal surgeons with expertise in inflammatory bowel diseases reviewed the literature in order to provide practical management pathways for perianal CD. Analysis of the literature was made according to the recommendations of the Haute Autorité de Santé (HAS) to establish a level of proof for each publication and then to propose a rank of recommendation. When lack of factual data precluded ranking according to the HAS, proposals based on expert opinion were written. Therefore, once all the authors agreed on a consensual statement, it was then submitted to all the members of the SNFCP. As initial literature review stopped in December 2014, more recent European or international guidelines have been published since and were included in the analysis.

RESULTS

MRI is recommended for complex secondary lesions, particularly after failure of previous medical and/or surgical treatments. For severe anal ulceration in Crohn's disease, maximal medical treatment with anti-TNF agent is recommended. After prolonged drainage of simple anal fistula by a flexible elastic loop or loosely tied seton, and after obtaining luminal and perineal remission by immunosuppressive therapy and/or anti-TNF agents, the surgical treatment options to be discussed are simple seton removal or injection of the fistula tract with biological glue. After prolonged loose-seton drainage of the complex anal fistula in Crohn's disease, and after obtaining luminal and perineal remission with anti-TNF ± immunosuppressive therapy, surgical treatment options are simple removal of seton and rectal advancement flap. Colostomy is indicated as a last option for severe APL, possibly associated with a proctectomy if there is refractory rectal involvement after failure of other medical and surgical treatments. The evaluation of anorectal stenosis of Crohn's disease (ARSCD) requires a physical examination, sometimes under anesthesia, plus endoscopy with biopsies and MRI to describe the stenosis itself, to identify associated inflammatory, infectious or dysplastic lesions, and to search for injury or fibrosis of the sphincter. Therapeutic strategy for ARSCD requires medical-surgical cooperation.

Sonographic appearance of anal cushions of hemorrhoids

AIM

To evaluate the diagnostic value of different sonographic methods in hemorrhoids.

METHODS

Forty-two healthy volunteers and sixty-two patients with grades I-IV hemorrhoids received two different sonographic examinations from January 2013 to January 2016 at the First and Second Hospitals of Xinjiang Medical University in a prospective way. We analyzed the ultrasonographic findings of these participants and evaluated the outcomes. Resected grades III and IV hemorrhoid tissues were pathologically examined. The concordance of ultrasonographic results with pathology results was assessed with the Cohen’s kappa coefficient.

RESULTS

All healthy volunteers and all patients had no particular complications related to sonography. There were no statistically significant differences between the participants regarding age (P = 0.5919), gender (P = 0.4183), and persistent symptoms (P > 0.8692). All healthy control participants had no special findings. However, 30 patients with hemorrhoids showed blood signals around the dentate line on ultrasonography. When grades I and II hemorrhoids were analyzed, there were no significant differences between transrectal ultrasound (TRUS), transperianal ultrasound (TPUS), and transvaginal ultrasound (TVUS) (P > 0.05). Grades III and IV hemorrhoids revealed blood flow with different directions which could be observed as a “mosaic pattern”. In patients with grades III and IV hemorrhoids, the number of patients with “mosaic pattern” as revealed by TRUS, TPUS and TVUS was 22, 12, and 4, respectively. Patients with grades III and IV disease presented with a pathologically abnormal cushion which usually appeared as a “mosaic pattern” in TPUS and an arteriovenous fistula in pathology. Subepithelial vessels of resected grades III and IV hemorrhoid tissues were manifested by obvious structural impairment and retrograde and ruptured changes of internal elastic lamina. Some parts of the Trietz’s muscle showed hypertrophy and distortion. Arteriovenous fistulas and venous dilatation were obvious in the anal cushion of hemorhoidal tissues. After pathological results with arteriovenous fistulas were taken as the standard reference, we evaluated the compatibility between the two methods according to the Cohen’s kappa co-efficiency calculation. The compatibility (Cohein kappa co-efficiency value) between “mosaic pattern” in the TPUS and arteriovenous fistula in pathology was very good (ĸ = 0.8939). When compared between different groups, TRUS presented the advantage that the mosaic pattern could be confirmed in more patients, especially for group A. There was a statistical difference when comparing group A with group B or C (P < 0.05 for both). There were obvious statistical differences between group A and group B with regard to the vessel diameter and blood flow velocity measured by TRUS (P < 0.05).

CONCLUSION

Patients with grades III and IV hemorrhoids present with a pathologically abnormal cushion which usually appears as a “mosaic pattern” in sonography, which is in accord with an arteriovenous fistula in pathology. There are clearly different hemorrhoid structures shown by sonography. “Mosaic pattern” may be a parameter for surgical indication of grades III and IV hemorrhoids.

Current applications of transperineal ultrasound in gastroenterology

Transperineal ultrasound is an inexpensive, safe and painless technique that dynamically and non-invasively evaluates the anorectal area. It has multiple indications, mainly in urology, gynaecology, surgery and gastroenterology, with increased use in the last decade. It is performed with conventional probes, positioned directly above the anus, and may capture images of the anal canal, rectum, puborectalis muscle (posterior compartment), vagina, uterus, (central compartment), urethra and urinary bladder (anterior compartment). Evacuatory disorders and pelvic floor dysfunction, like rectoceles, enteroceles, rectoanal intussusception, pelvic floor dyssynergy can be diagnosed using this technique. It makes a dynamic evaluation of the interaction between pelvic viscera and pelvic floor musculature, with images obtained at rest, straining and sustained squeezing. This technique is an accurate examination for detecting, classifying and following of perianal inflammatory disease. It can also be used to sonographically guide drainage of deep pelvic abscesses, mainly in patients who cannot undergo conventional drainage. Transperineal ultrasound correctly evaluates sphincters in patients with fecal incontinence, postpartum and also following surgical repair of obstetric tears. There are also some studies referring to its role in anal stenosis, for the measurement of the anal cushions in haemorrhoids and in chronic anal pain.

Transperineal ultrasonography for evaluation of the perianal fistula and abscess in pediatric Crohn disease: preliminary study

PURPOSE

To assess the feasibility and effectiveness of transperineal ultrasonography (TPUS) for the evaluation of perianal Crohn disease (PCD) in pediatric patients.

METHODS

Between September 2010 and August 2013, 64 TPUS examinations were performed in 43 patients (34 males and 9 females; mean age±standard deviation, 13.3±2.4 years; age range, 6 to 17 years) to evaluate PCD. The pain severity, location, and activity of perianal fistula, the presence of an abscess, and anal canal hyperemia were retrospectively evaluated. Spearman rank correlation analysis was performed to assess the relationship between the severity of the pain and the fistula activity, the presence of an abscess, and anal canal hyperemia.

RESULTS

All examinations were successfully performed. Thirty-nine examinations (60.9%) were performed without any pain experienced by the patient, 19 examinations (29.7%) with mild pain, five examinations (7.8%) with moderate pain, and one examination (1.6%) with severe pain. The pain severity was correlated with the fistula activity (P<0.01). An anterior fistula location was more common than a posterior location. Active fistulas and abscesses were identified during 30 examinations (46.9%) and 12 examinations (18.8%), respectively. Anal canal hyperemia was identified in 31 examinations (48.4%).

CONCLUSION

TPUS with a color Doppler study is useful for visualizing a perianal fistula or abscess and for assessing its inflammatory activity in pediatric Crohn patients.

Transperineal perineal ultrasound versus magnetic resonance imaging in the assessment of perianal Crohn's disease

BACKGROUND

To assess the accuracy of transperineal ultrasound (TPUS), in comparison with magnetic resonance imaging (MRI), in classifying perianal Crohn's disease (CD) according to Parks' classification and the American Gastroenterological Association criteria.

METHODS

Fifty-nine consecutive patients with confirmed or suspected perianal CD underwent TPUS and MRI within 10 days. An independent expert surgical evaluation, which took into account proctological and MRI findings, was used as the gold standard. Fistulae and perianal disease were classified according to Parks' classification and American Gastroenterological Association criteria, respectively.

RESULTS

Forty-six patients showed 64 fistulae (9 intersphincteric, 34 transsphincteric, 2 suprasphincteric, 9 extrasphincteric, and 10 anovaginal) and 23 abscesses were also found. Fifty-one of 54 perianal fistulae (per-lesion sensitivity: 94.4%) and 9 of 10 anovaginal fistulae (sensitivity: 90.0%) were detected and 58 were correctly classified by TPUS (sensitivity: 90.6%; positive predictive value: 93.4%). Overall, TPUS correctly detected and classified the fistulae in 89% of patients and the agreement for classifying perianal fistulae between TPUS and MRI was excellent (K value: 0.783). In contrast, 11 of 23 abscesses were correctly diagnosed by TPUS (sensitivity: 47.8%); although 14 abscesses were diagnosed by TPUS, only 11 were confirmed by MRI (positive predictive value: 78.6%). Overall, TPUS correctly detected and classified fistulae and associated abscesses in 67.3% of patients. Agreement between MRI and TPUS in discriminating simple (15) and complex (29) perianal disease was fairly good (K value: 0.57).

CONCLUSIONS

TPUS is a simple and accurate diagnostic method for classifying perianal fistulae in CD and could be used for the preliminary assessment and follow-up of perianal CD.

Transperineal ultrasonography in perianal Crohn's disease and recurrent cryptogenic fistula-in-ano

AIM

Successful anal fistula care is aided by specialized imaging accurately defining the site of the internal opening and fistula type. Imaging techniques are complementary, designed to answer specific anatomical questions. There are limited data concerning the clinical value of transperineal ultrasound (TP-US) in both cryptogenic fistula-in-ano and perianal Crohn's disease (PACD). The aim of the study was to assess the accuracy of TP-US compared with operative findings in patients with perirectal sepsis.

METHOD

Patients with recurrent cryptogenic anal fistula and PACD referred for sonography were examined using TP-US by a single examiner blinded to the operative results. Fistulae were categorized by the Parks classification predicting the site of the internal fistula opening. Ancillary horseshoe collections, abscesses and secondary tracks were defined.

RESULTS

Fourteen patients with PACD and 27 patients with recurrent cryptogenic fistula-in-ano were analysed with comparative images and operative data. Correlation of fistula type for cryptogenic and PACD patients respectively was 23/27 (85.2%) and 12/14 (85.7%), with a correlative internal opening site (when found at surgery) of 16/22 (72.3%) and 12/14 (85.7%). Misclassification of fistula type in cryptogenic cases occurred in the presence of ancillary abscesses with associated acoustic shadowing. In PACD patients, TP-US was used when anal stenosis precluded endoanal ultrasonography, assisting in the diagnosis of recto-vaginal fistulae.

CONCLUSION

TP-US is a useful complementary technique to assess fistula-in-ano and has special advantage when there is anal canal distortion, complex fistula type or suspicion of a recto-vaginal fistula.

Transperineal ultrasonography as a complementary diagnostic tool in identifying acute perianal sepsis

BACKGROUND

Successful anal fistula care in complex cases can be assisted by specialized imaging which accurately defines the site of the internal fistula opening and the fistula type. There are currently limited data concerning the clinical indications for and accuracy of transperineal ultrasound (TP-US) in acute perianal sepsis. The aims of this study were to compare the anatomical interpretation of TP-US images with magnetic resonance imaging (MRI) and surgical findings in an unselected patient cohort presenting with acute perianal sepsis.

METHODS

Sixty-seven consecutive patients with acute anorectal sepsis referred from the surgical department were examined using TP-US and Gadolinium-enhanced MRI with both examiners blinded to the surgical results. Fistulae were categorized by the Parks' classification of fistula type.

RESULTS

Thirty-six abscesses were detected by MRI, 38 by TP-US and 30 by surgical examination. Operatively discordant cases showed only ischiorectal panniculitis. TP-US was more accurate in the diagnosis of superficial sepsis and MRI in the diagnosis of deep-seated perirectal infection. TP-US and MRI show concordance with operative findings in fistula diagnosis with a tendency for TP-US to overdiagnose trans-sphincteric fistulae and MRI to over diagnose extra-sphincteric fistulae. Comparison of TP-US with MRI showed good agreement for perianal abscess diagnosis (τ = 0.82) and for fistula diagnosis (τ = 0.68). For fistulae, TP-US showed moderate agreement with surgery (τ = 0.43) with only fair agreement between MRI and surgery (τ = 0.29).

CONCLUSIONS

Transperineal ultrasound complements other imaging modalities in the anatomical diagnosis of acute perianal abscesses and fistulae. It has specific advantages over other techniques and is accurate in the detection of superficially located perirectal sepsis showing concordance with MRI and surgical findings.

Ultrasonographic assessment of patients referred with chronic anal pain to a tertiary referral centre

BACKGROUND

Chronic anal pain is relatively common as a presentation to specialist physicians and surgeons. Currently, it is regarded as a functional disorder upon the exclusion of occult intersphincteric sepsis. Our study assessed an unselected cohort of patients presenting with chronic previously undiagnosed anal pain using routine ultrasonography.

METHODS

All patients referred to a tertiary gastroenterology service between January 2005 and January 2008 with a diagnosis of chronic anal pain (>3 months duration with no clinical anorectal signs) underwent endoanal and static and dynamic transperineal ultrasound to assess for the frequency and pattern of occult intersphincteric sepsis.

RESULTS

Of 1,580 patients referred, there were 146 presenting with chronic anal pain as a main symptom. Of these, 37 (25.3%) had intersphincteric sepsis (ISS) diagnosed with ultrasound examination with 17 undergoing evaluable surgery. There was a male preponderance (70.3%) with the diagnosis being made in 46% of cases after 6 months of symptoms and with 80.8% having posteriorly located sepsis. This occurred on a background of 62% having previous acute proctological conditions. There was complete ultrasonographic and operative concordance with 15 becoming asymptomatic after surgery at a mean follow-up of 6 months.

CONCLUSION

Occult intersphincteric sepsis is not uncommon and is diagnosed using routine ultrasonography at the time of clinical presentation. Endoanal and transperineal ultrasound is recommended as part of the investigative armamentarium to exclude categorization as functional anorectal pain. This is currently not part of the Rome III coding for such a diagnosis suggesting a revision of these diagnostic criteria for the ultimate diagnosis of functional proctalgia.

Endoanal ultrasound in benign anorectal disorders: clinical relevance and possibilities

Endoanal ultrasound is a well-established technique used to evaluate benign anorectal disorders. The technique is easy to perform, has a short learning curve and causes very little discomfort. Reconstruction of 3D images is possible. The clinical indications for endoanal ultrasound in benign anorectal diseases are fecal incontinence and peri-anal fistula. Sphincter defects can be depicted with precision and correlate perfectly with surgical findings. Furthermore, an impression of sphincter atrophy can be established. With perianal fistula the tracts can be visualized. Introducing hydrogen peroxide via the external fistula opening improves imaging. Endoanal ultrasound and MRI have comparable results in diagnosing anorectal disorders.

The role of transperineal ultrasonography in the assessment of the internal opening of cryptogenic anal fistula

PURPOSE

The aim of this study was to assess the reliability of transperineal ultrasonography (TPUS) in the pre-operative identification of the internal opening of anal fistulas compared to conventional proctological examination and operative findings.

METHODS

Forty-three patients with anal fistula were assessed by TPUS with and without the use of hydrogen-peroxide injection (E-TPUS) in an attempt to identify the internal opening. Results were compared to preoperative conventional examination and operative findings.

RESULTS

Operative assessment showed an anterior internal opening in 29 patients (67.4%) and a posterior opening in 14 (32.6%). Compared to the operative findings, the agreement rate for the identification of the internal opening was 74.4% for physical examination alone, 93.0% for TPUS and 90.7% for E-TPUS. Physical examination was less accurate in detecting the internal opening than both TPUS (p=0.014) and E-TPUS (p=0.026).

CONCLUSIONS

TPUS and E-TPUS are superior to physical examination in the identification of internal openings in anal fistulas. Hydrogen peroxide injection does not provide additional advantages.

Imaging of perianal Crohn's disease

Perianal fistulas and abscesses are common complications of Crohn's disease, affecting up to 50% of patients during their disease course. Accurate diagnosis and classification of perianal disease is crucial before and during treatment to plan an adequate approach for each patient and to avoid irreversible functional consequences. Although examination under anaesthesia has been considered the gold standard for diagnosis and classification of Crohn's disease perianal fistulas, taken alone it does not have perfect accuracy, stressing the need for concomitant or alternative, non-invasive, methods of evaluation. In this context, imaging modalities assessed for diagnosis, classification and monitoring of Crohn's disease perianal fistulas include pelvic magnetic resonance imaging, anorectal endoscopic ultrasonography, transcutaneous perianal ultrasound, fistulography and computed tomography. In particular, magnetic resonance imaging and endoscopic ultrasonography findings have shown the best accuracy, and the ability to influence therapeutic management of these patients. For transcutaneous perianal ultrasound too, good preliminary data have been reported. This paper reviews the available data on imaging methods for the management of perianal Crohn's disease.