Use of endoanal ultrasound in patients with rectovaginal fistulas

ACR Appropriateness Criteria® Anorectal Disease

This review summarizes the relevant literature for the selection of the initial imaging in 4 clinical scenarios in patients with suspected inflammatory disease or postoperative complication of the anorectum. These clinical scenarios include suspected perianal fistula or abscess; rectovesicular or rectovaginal fistula; proctitis or pouchitis; and suspected complication following proctectomy, coloproctectomy, or colectomy with a pouch or other anastomosis. The appropriateness of imaging modalities as they apply to each clinical scenario is rated as usually appropriate, may be appropriate, and usually not appropriate to assist the selection of the most appropriate imaging modality in the corresponding clinical scenarios of anorectal disease. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Ultrasound in the Diagnosis of Malignant Pelvic Fistulas: Sonographic Findings in Correlation with Computed Tomography Imaging

Even though ultrasound is an extensively used imaging modality, it has not been effectively utilized in the evaluation and diagnosis of malignant pelvic fistulas. In this study, we tried to correlate the accuracy of sonographic findings in identifying malignant fistulas with that of computed tomography (CT) imaging. Thirty-five patients with advanced pelvic malignancies were examined over a period of 2 y. Patients underwent CT of the abdomen and pelvis with intravenous and oral/rectal contrast followed by ultrasound of the abdomen. Sonographic examinations were performed using a standardized protocol with a full bladder. Real-time ultrasound images of the abdomen and pelvis in multiple planes were acquired and stored as both image files and audio-video interleaves (AVIs). On ultrasound, the majority of the fistulas were visualized either as a continuous hyper-echoic tract within a hypo-echoic neoplastic mass ("air contrast sign") or as multiple discontinuous hyper-echoic foci with "ring down" artifacts. The sensitivity and specificity of ultrasound in the detection of malignant fistulas were 72% (confidence interval [CI]: 52%-87%) and 66% (CI: 22%-95%), respectively. We also reviewed the literature and compared the sensitivities of ultrasound in the detection of various types of pelvic fistulas obtained in previous studies with those in the present study. Results suggest that although ultrasound cannot be used as a primary imaging modality for the detection of fistulas, it can provide the earliest clue to the presence of a malignant fistula.

Evaluation of genitourinary fistulas in pelvic malignancies with etiopathologic correlation: role of cross sectional imaging in detection and management

OBJECTIVE

Genitourinary fistulas in pelvic malignancies are abnormal communications occurring due to either locally advanced tumours invading the surrounding organs or post-therapeutic complications of malignancies. In this article we review and describe the role of cross-sectional imaging findings in the management of genitourinary fistulas in pelvic malignancies.

METHODS

A retrospective study, for the period January 2012 to December 2018, was undertaken in patients with pelvic malignancies having genitourinary fistulas. The cross-sectional (CT and MRI) imaging findings in various types of fistulas were reviewed and correlated with the primary malignancy and the underlying etiopathology.

RESULTS

Genitourinary fistulas were observed in 71 patients (6 males, 65 females). 11 types of fistulas were identified in carcinomas of cervix, rectum, ovary, urinary bladder, sigmoid colon, vault, endometrium and prostate. The commonest were rectovaginal and vesicovaginal fistulas. 13 patients had multiple fistulas. The sensitivity, specificity, positive and negative predictive values of CT and MRI are 98%, 100%, 66%, 98% and 95%, 25%, 88% and 50% respectively. Contrast-enhanced CT with oral and rectal contrast is more sensitive and specific than MRI in the evaluation of genitourinary fistulas.

CONCLUSION

Imaging findings significantly influence the management and outcome of genitourinary fistulas in pelvic malignancies. Contrast-enhanced CT is the imaging modality of choice in the evaluation of pelvic fistulas associated with malignancies and MRI is complimentary to it.

ADVANCES IN KNOWLEDGE

To our knowledge, this study is the first of its kind wherein the mean duration of occurrence of fistulas in pelvic malignancies is correlated with the underlying etiopathology.

Use of the Martius advancement flap for low rectovaginal fistulas

AIM

The percentage recurrence after any surgical treatment for low rectovaginal fistula (LRVF) is unacceptably high. The aim of this study was to evaluate the short- and long-term results of the Martius procedure in a carefully selected series of patients with a LRVF of at least 1 cm diameter who had had at least two previous surgeries or in the presence of chronically inflamed local tissues.

METHOD

Between January 2009 and April 2017, 24 patients with the abovementioned features were prospectively included in this study. Success was defined both as the absence of any subjective symptoms and the fistula, as confirmed by evaluation under anaesthesia. Postoperative complications were assessed using the Clavien-Dindo classification. Quality of life (SF-12 score), quality of sexual life [Female Sexual Function Index (FSFI) score] and continence [Cleveland Clinic Incontinence Score (CCIS)] were also determined pre- and postoperatively.

RESULTS

The mean follow-up was 42 ± 29 months (range 3-101 months). The overall success rate was 91.3% (22/24 patients). The median operation time was 50 min (range 45-70 min), and the median hospital stay was 3.5 days (range 3-5 days). No major complications occurred. Pre- and postoperative CCIS did not differ [1 (range 0-3.5)]. The postoperative SF-12 score improved both in terms of the physical (33.6 ± 7.2 vs 50.8 ± 7.8; P < 0.001) and mental (32.6 ± 6.7 vs 56.3 ± 7.8; P < 0.001) components. FSFI improved from 19.5 ± 6.6 to 24.4 ± 6.3 (P < 0.001).

CONCLUSION

The Martius procedure should be considered as the first-line method of treatment in carefully selected cases of LRVF.

The treatment of anal fistula: second ACPGBI Position Statement - 2018

It is over 10 years since the first ACPGBI Position Statement on the management of anal fistula was published in 2007. This second edition is the result of scrutiny of the literature published during this time; it updates the original Position Statement and reviews the published evidence surrounding treatments for anal fistula that have been developed since the original publication.

Utility of Endoanal Ultrasonography in Assessment of Primary and Recurrent Anal Fistulas and for Detection of Associated Anal Sphincter Defects

BACKGROUND

Tridimensional endoanal ultrasonography (3D-EAUS) has been used for the assessment of various anorectal lesions. Previous studies have reported good accuracy of 3D-EAUS in preoperative assessment of fistula-in-ano (FIA). This study aimed to assess the diagnostic utility of 3D-EAUS in preoperative evaluation of primary and recurrent FIA and its role in detection of associated anal sphincter (AS) defects.

PATIENTS AND METHODS

Prospectively collected data of patients with FIA who were investigated with 3D-EAUS were reviewed. The findings of EAUS were compared with the intraoperative findings, the reference standard, to find the degree of agreement regarding the position of the internal opening (IO) and primary tract (PT), and presence of secondary tracts using kappa (k) coefficient test. A subgroup analysis was performed to compare the accuracy and sensitivity of EAUS for primary and recurrent FIA.

RESULTS

Of the patients, 131 were included to the study. EAUS had an overall accuracy of 87, 88.5, and 89.5% in detection of IO, PT, and AS defects, respectively. There was very good concordance between the findings of EAUS and intraoperative findings for the investigated parameters (kappa = 0.748, 0.83, 0.935), respectively. Accuracy and sensitivity of EAUS in recurrent FIA were insignificantly lower than primary cases. EAUS detected occult AS defects in 5.3% of the patients studied.

CONCLUSION

The diagnostic utility of 3D-EAUS was comparable in primary and recurrent FIA. 3D-EAUS was able to detect symptomatic and occult AS defects with higher accuracy than clinical examination.

Genital and reproductive organ complications of Crohn disease: technical considerations as it relates to perianal disease, imaging features, and implications on management

OBJECTIVE

A relatively large proportion of patients with Crohn disease (CD) develop complications including abscess formation, stricture, and penetrating disease. A subset of patients will have genital and reproductive organ involvement of CD, resulting in significant morbidity. These special circumstances create unique management challenges that must be tailored to the activity, location, and extent of disease. Familiarity with the epidemiology, pathogenesis, imaging features, and treatment strategies for patients with genital CD can aid imaging diagnoses and guide appropriate patient management. The purpose of this study is to illustrate the spectrum of CD in the genital tract and reproductive organs and discuss the complex management strategies in these patients as it relates to imaging.

CONCLUSION

Given the impact on patient outcome and treatment planning, familiarity with the epidemiology, pathogenesis, imaging features, and treatment of patients with genital Crohn disease can aid radiologic diagnoses and guide appropriate patient management.

MRI in evaluation of perianal fistulae

BACKGROUND

Fistula is considered to be any abnormal passage which connects two epithelial surfaces. Parks' fistulae classification demonstrates the biggest practical significance and divides fistulae into: intersphincteric, transsphincteric, suprasphincteric and extrasphincteric. Etiology of perianal fistulae is most commonly linked with the inflammation of anal glands in Crohn's disease, tuberculosis, pelvic infections, pelvic malignant tumours, and with the radiotherapy. Diagnostic method options are: RTG fistulography, CT fistulography and magnetic resonance imaging (MRI) of pelvic organs.

PATIENTS AND METHODS

We have included 24 patients with perirectal fistulae in the prospective study. X-rays fistulography, CT fistulography, and then MRI of the pelvic cavity have been performed on all patients. Accuracy of each procedure in regards to the patients and the etiologic cause have been statistically determined.

RESULTS

29.16% of transphincteric fistulae have been found, followed by 25% of intersphincteric, 25% of recto-vaginal, 12.5% of extrasphincteric, and 8.33% of suprasphincteric. Abscess collections have been found in 16.6% patients. The most frequent etiologic cause of perianal fistulae was Crohn's disease in 37.5%, where the accuracy of classification of MRI was 100%, CT was 11% and X-rays 0%. Ulcerous colitis was the second cause, with 20.9% where the accuracy of MRI was 100%, while CT was 80% and X-rays was 0%. All other etiologic causes of fistulae were found in 41.6% patients.

CONCLUSIONS

MRI is a reliable diagnostic modality in the classification of perirectal fistulae and can be an excellent diagnostic guide for successful surgical interventions with the aim to reduce the number of recurrences. Its advantage is that fistulae and abscess are visible without the need to apply any contrast medium.

Are there predictors of outcome following rectovaginal fistula repair?

BACKGROUND

Rectovaginal fistula is a distressing condition for patients and for physicians who are continuously challenged in providing durable treatment options. The aim of this study is to assess the results of rectovaginal fistula repair and identify predictive factors for poor outcome.

METHODS

Retrospective analysis of patients who underwent rectovaginal fistula repair from 1988 to 2008 was performed. chi tests and logistical regression analysis were used to study treatment outcomes according to the following fistula characteristics: etiology, size, location, and number of prior attempts at fistula repair. In addition, patient factors such as age, body mass index, smoking history, comorbid condition of diabetes, use of steroid and immunosuppressive medications, number of prior vaginal deliveries, and presence of a diverting stoma were analyzed.

RESULTS

A total of 184 procedures were performed in 125 patients. Inflammatory bowel disease was the most common indication for surgery (45.6%), followed by obstetric injury (24%) and surgical trauma (16%). The mean duration of fistula presence was 31.2 months. The procedures performed included endorectal advancement flap (35.3%), gracilis muscle interposition (13.6%), seton placement (13.6%), and transperineal (8.7%) and transvaginal repair (8.1%). The overall success rate per procedure was 60%, with no difference in recurrence rates based on the type of repair. Patients with Crohn's disease had more recurrent fistulas (44.2% success per procedure; P < .01), although 78% eventually healed after an average of 1.8 procedures. Patients with obstetric injuries had an 89% success rate after an average of 1.3 procedures per patient, which is similar to the success rate for traumatic fistulas. Pouch vaginal fistulas had a 91% success rate after an average of 1.6 procedures per patient. The overall success rate per patient was 88% after multiple procedures with a mean follow-up of 16.3 months. Age, body mass index, diabetes, use of steroids and immunosuppressive agents, size and location of the fistula, number of vaginal deliveries, time interval between a recurrent episode and subsequent repair, and the presence of fecal diversion did not affect outcomes. The presence of Crohn's disease and a smoking history are strongly associated with rectovaginal fistula recurrence (P = .02).

CONCLUSIONS

Despite a relatively low initial success rate (60%), most rectovaginal fistulas can be successfully repaired with subsequent operations. Crohn's disease and smoking are associated with adverse outcomes.

Three-dimensional endoanal ultrasonographic assessment of an anal fistula with and without H2O2 enhancement

AIM: To evaluate the effectiveness of three-dimensional endoanal ultrasound (3D-EAUS) in the assessment of anal fistulae with and without H₂O₂ enhancement.

METHODS: Sixty-one patients (37 males, aged 17-74 years) with anal fistulae, which were not simple low types, were evaluated by physical examination and 3D-EAUS with and without enhancement. Fistula classification was determined with each modality and compared to operative findings as the reference standard.

RESULTS: The accuracy of 3D-EAUS was significantly higher than that of physical examination in detecting the primary tract (84.4% vs 68.7%, P = 0.037) and secondary extension (81.8% vs 62.1%, P = 0.01) and localizing the internal opening (84.2% vs 59.7%, P = 0.004). A contrast study with H₂O₂ detected several more fistula components including two primary suprasphincteric fistula tracks and one supralevator secondary extension, which were not detected on non-contrast study. However, there was no significant difference in accuracy between 3D-EAUS and H₂O₂-enhanced 3D-EAUS with respect to classification of the primary tract (84.4% vs 89.1%, P = 0.435) or secondary extension (81.8% vs 86.4%, P = 0.435) or localization of the internal opening (84.2% vs 89.5%, P = 0.406).

CONCLUSION: 3D-EAUS was highly reliable in the diagnosis of an anal fistula. H₂O₂ enhancement was helpful at times and selective use in difficult cases may be economical and reliable.

Fistulas in malignant gynecologic disease: etiology, imaging, and management

A fistula that occurs in association with a malignancy of the female reproductive tract may be caused by a primary or recurrent tumor or may be a complication of surgery or radiation therapy. Identification of the cause, complexity, and location of a fistula is essential for optimal management planning. Radiologic imaging, particularly with computed tomography and magnetic resonance techniques, is invaluable for the assessment of gynecologic fistulas and may help direct the clinician toward the most appropriate management pathway. The modality and technique selected for the initial imaging evaluation depend largely on the clinical history and manifestations. However, imaging with a combination of techniques often is required for accurate diagnosis and effective treatment planning. Radiologists should be familiar with suggestive clinical signs and symptoms as well as with the characteristic appearances of rectovaginal, vesicovaginal, ureterovaginal, enterovesical, enterocutaneous, and other pelvic fistulas at multimodality imaging.

Rectovaginal fistula: a new approach by stapled transanal rectal resection

Many surgical procedures have been developed to repair rectovaginal fistulas even if no "procedure of choice" is reported. The authors report a case of relatively uncommon, complex, medium-high post-obstetric rectovaginal fistula without sphincteral lesions and treated with a novel tailored technique. Our innovative surgical management consisted of preparing the neck of the fistula inside the vagina and folding it into the rectum so as to enclose the fistula within two semicontinuous sutures (stapled transanal rectal resection); no fecal diversion was performed. Postoperative follow-up at 9 months showed no recurrence of the fistula.

Endoanal ultrasonography in establishing the diagnosis of fecal incontinence

Visualisation of the rectum, rectoanal junction and adjacent structures is very demanding and challenging both with technical and medical side. Local staging of rectal and anal tumor and perianal neoplasm by conventional and sibgle slice CT or by barium enema study is not so valuable. These methods can not visualise fistulous communication in inflamatory bowel diseases and have not any role in evaluation of fecal incontinence. During last decade, endoscopic ultrasound and magnetic resonance imaging have been recognised as methods of choice in establishing diagnosis of rectal, perirectal, anal and perianal diseases. The aim of this article is to review the possibilities of endoanal ultrasound in evaluation of fecal incontinence.

Magnetic resonance fistulography for the demonstration of anovaginal fistula: an alternative imaging technique?

Anovaginal fistulae (AVF) are frequently seen in patients with inflammatory bowel disease, especially in Crohn disease with active colonic inflammation. Herein, we report a 21-year-old woman with Crohn disease suffering from vaginal discharge and anal pain. Although clinical presentation was very suggestive of AVF, physical examination and colonoscopy were inconclusive. We used an alternative technique and performed magnetic resonance fistulography by applying rectal contrast for the demonstration of AVF.

Endoanal ultrasound evaluation of anorectal diseases and disorders: technique, indications, results and limitations

Imaging of the rectum, anorectal junction and surrounding tissues is both difficult and technically challenging. CT and conventional barium studies offer limited information in local staging of rectal and perirectal neoplasms, anal carcinomas and extension perianal fistulas in patients with inflamamatory bowel disease, or in evaluating patients with fecal incontinence. During past decade, sonography and MR imaging have resulted in significant improvement in the imaging of rectal and perirectal and anal and perianal disease. The aim of this article is to review possibility of the EAUS in the evaluation both normal anal anatomy and anorectal disease and disorders (anal carcinoma, sphincter defects, anal fistulas, perianal abscesses and other pathological conditions).

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.

Endosonographic imaging of anorectal diseases

OBJECTIVE

The normal sonographic anatomy of the anorectum, sonographic findings of anorectal diseases, and indications and limitations of endosonography compared with magnetic resonance imaging are reviewed. Methods. Endosonographic imaging was performed with a Siemens (Erlangen, Germany) FI 400 ultrasound scanner with an end-fire 7.5-MHz biplane endorectal probe and a B-K Medical (Sandhoften, Denmark) scanner with an 1850 axial-type side-fire 5.0- to 10.0-MHz rotating endoscopic probe.

RESULTS

Rectal carcinoma appears on endorectal sonography as a low-echogenicity lesion that abruptly interrupts the normal sequence of layers. The internal anal sphincter is seen very clearly on endoanal sonography, and it is easy to appreciate atrophy and small tears of this sphincter. Endoanal sonography cannot accurately show thinning of the external anal sphincter. Peroxide-enhanced endoanal sonography is especially useful for patients with recurrent perianal fistulas in whom scarring should be distinguished from recurrent fistulas and detection of the internal opening. However, sonography does not provide an adequate deep and global display of all adjacent pelvic and perineal spaces.

CONCLUSIONS

Endosonography can accurately stage primary rectal tumors and assess the internal anal sphincter. Peroxide-enhanced 3-dimensional imaging can increase the utility of endoanal sonography in detection and characterization of perianal fistulas and planning of optimal therapy. However, magnetic resonance imaging can be used a complementary modality to endosonography, especially for evaluation of external anal sphincter atrophy and deep pelvic inflammation.

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.

Laparoscopic repair of high rectovaginal fistula: is it technically feasible?

BACKGROUND

Rectovaginal fistula (RVF) is an epithelium-lined communication between the rectum and vagina. Most RVFs are acquired, the most common cause being obstetric trauma. Most of the high RVFs are repaired by conventional open surgery. Laparoscopic repair of RVF is rare and so far only one report is available in the literature.

METHODS

We present a case of high RVF repaired by laparoscopy. 56-year-old female who had a high RVF following laparoscopic assisted vaginal hysterectomy was successfully operated laparoscopically. Here we describe the operative technique and briefly review the literature.

RESULTS

The postoperative period of the patient was uneventful and after a follow up of 6 months no recurrence was found.

CONCLUSION

Laparoscopic repair of high RVF is feasible in selected patients but would require proper identification of tissue planes and good laparoscopic suturing technique.

Transperineal repair of obstetric-related anovaginal fistula

BACKGROUND

To describe an operative technique for the repair of anovaginal fistulae secondary to obstetric injury and to assess its functional outcome and patient satisfaction.

METHODS

An operative repair involving division of the anovaginal fistula, closure of rectal and vaginal walls, anterior levatoplasty and overlapping sphincteroplasty is described. Postoperative complications and recurrence were recorded. A telephone interview was carried out to assess the functional outcome and the satisfaction score.

RESULTS

Seven consecutive patients had a repair of an obstetric-related anovaginal fistula. Their mean age was 34 years (range: 22-72). They had a mean duration of symptoms of 14 months (range: 1.5-54). Four patients did not have any previous repair and no stoma was necessary in any of the seven patients. There was no significant postoperative complication and only one recurrence. Telephone interviews were conducted for six patients and one was lost to follow-up. The mean follow-up period was 24 months (11-35). The Wexner's continence score improved from a mean preoperative score of 13.4 to a mean postoperative score of 5.6. With satisfaction scores ranging from +3 to -3 (+3 indicating complete satisfaction and -3 indicating complete dissatisfaction), five patients scored 1 and one scored 0.

CONCLUSION

This technique is straightforward and effective in healing obstetric-related anovaginal fistula. It achieves improved continence and reasonable satisfaction.

Endoanal and endorectal ultrasound: applications in colorectal surgery

Endoanal and endorectal ultrasound have an important role in colorectal surgery. They can be applied in the management of faecal incontinence, rectal tumours and inflammatory perianal conditions. In faecal incontinence, anal ultrasound will confirm the presence or absence of sphincter defects. This will direct any operative intervention such as direct sphincter repair. Ultrasound in rectal cancer allows staging of the tumour by assessing the depth of invasion through the bowel wall and involvement of mesenteric nodes. Such staging might influence the choice of operation and determine which patients might benefit from preoperative chemotherapy and radiotherapy. Ultrasound has a particular role in recurrent and complex anal fistula and perianal sepsis. Preoperative and perioperative planning with accurate delineation of fistula tracts, extensions and sphincter involvement might help prevent recurrence and impaired continence from sphincter damage after surgery. Correct interpretation of ultrasound images requires training and experience so that the results can be properly correlated with the clinical situation.

Surgeon-performed ultrasound: endorectal ultrasound

Endorectal (ERUS) and endoanal (EAUS) ultrasound imaging is increasingly being performed by surgeons in the office and outpatient setting for the assessment of both benign and malignant disease. Multiple studies have demonstrated the accuracy of these modalities in identifying pertinent anatomy and anatomic abnormalities. The ultrasound is easily tolerated by most patients, and is easily performed with minimal preparation on the patient's part. The ability of the surgeon to perform and interpret this straight forward diagnostic procedure allows for the simplification of the diagnostic process and a more rapid determination of treatment options for the patient.

Fistulas of the Genitourinary Tract: A Radiologic Review

Fistulas of the genitourinary tract have diverse anatomic locations, causes, and clinical features. They can involve the upper urinary tract (kidney, ureter), the lower urinary tract (bladder, urethra), or the female reproductive tract (vagina, uterus). Causes include infection, inflammatory disease, neoplasms, congenital conditions, trauma, and iatrogenic injury. Diagnosis of genitourinary tract fistulas usually requires radiologic studies performed with fluoroscopic or cross-sectional modalities. Fistulography is the most direct means of visualizing a fistula and should be considered when feasible (eg, cutaneous fistulas). Intravenous urography and pyelography or ureterography are mainstays of investigation of the upper tract. Likewise, voiding cystourethrography and urethrography are central to study of the lower tract. Cross-sectional techniques, in particular computed tomography, are increasingly useful for diagnosis and are considered the primary test in some cases. Radiologists should be familiar with the radiologic features of genitourinary tract fistulas for accurate diagnosis and treatment planning. Management approaches depend on the type of fistula, the degree of morbidity, and the overall functional status of the patient and vary from conservative observation to aggressive surgical repair.

Comparison of contrast-enhanced with non-contrast endosonography in the diagnostics of anal fistulas

The objective of this paper is to compare the accuracy of standard, non-contrast endosonography (EAS) with contrast-enhanced endosonography (CE-EAS) in the diagnosis of anal fistulas. The group consisted of 126 patients (mean age: 43.1 years) with the clinical diagnosis of anal fistula. For anal endosonography, a Bruel & Kjaer unit with a 7.0-MHz transducer was used with a 3% solution of hydrogen peroxide as the contrast agent (1, 2, 3). In each case, EAS and CE-EAS diagnoses of the type and complexity of anal fistula, as well as the location of the internal opening, were determined. Results showed that CE-EAS was significantly more accurate in diagnosing the type of anal fistulas than NC-EAS (97 vs. 94%, respectively; P=02275), and in differentiating simple from complex tracks (92 vs. 75%, respectively; P<0.00001). CE-EAS was much more accurate in patients with recurrent fistulas (57 vs. 92%, respectively; P<0.00006), whereas in a subgroup of primary tracks, both methods were of comparable accuracy. Sensitivities of CE-EAS and EAS for internal opening were 89 and 65%, respectively. The conclusion of this paper is that CE-EAS significantly increases the accuracy of standard non-contrast EAS and is especially beneficial for the differentiation between simple and complex tracks.

Perianal Crohn's disease

BACKGROUND

The management of perianal Crohn's disease is difficult. A wide variety of treatment options exist although few are evidence based.

METHODS

A search was conducted using the National Library of Medicine for articles on perianal Crohn's disease and its incidence, classification, assessment and management.

RESULTS AND CONCLUSION

Perianal Crohn's disease can manifest as skin tags, ulcers, fissures, abscesses, fistulas or stenoses. Improved radiological imaging with endoanal anal ultrasonography and magnetic resonance imaging has improved its assessment and may be used to predict outcome after surgery. Many treatment options exist. During acute complications they are generally aimed at resolving the immediate problem and limiting damage to anal and perianal tissues; this may be a 'bridge' to definitive treatment. The likelihood of success of definitive treatment must be weighed against the risk of complications, especially faecal incontinence.

Anovaginal Fistulas: Evaluation with Endoanal MR Imaging

PURPOSE

To evaluate endoanal magnetic resonance (MR) imaging in the assessment of anovaginal fistulas and associated findings.

MATERIALS AND METHODS

In a retrospective descriptive study, two radiologists systematically reviewed MR findings in 20 patients with a clinically proved anovaginal fistula and looked for the main fistula tract, the internal opening in the anal canal and/or vagina, secondary fistula tracts, abscesses within the rectovaginal septum, and sphincter damage. Interobserver variability was calculated, and clinical records were searched for possible underlying causes that could explain the complexity of anovaginal fistulas. The kappa value was calculated. Patients with or without a complex anovaginal fistula were compared in regard to the presence of any underlying disease or condition. Statistical significance was calculated with the Fisher exact test.

RESULTS

In all 20 patients, anovaginal fistulas were identified on T2-weighted MR images as predominantly high-signal-intensity linear abnormalities extending between the anal canal and the vagina. In all patients, the fistulas were typically located in the sagittal plane, and the mean distance from the anal verge to the fistula was 25.0 mm (range, 13-32 mm). The internal opening in the anal canal was detected in all patients. The internal opening in the vagina was detected in 19 (95%) patients. In seven (35%) patients, an anovaginal fistula with an additional abnormality was found and included an abscess within the rectovaginal septum (n = 1), a perianal fistula (n = 3), and a perianal fistula in combination with an abscess (n = 3). Defects of the external anal sphincter were present in three (15%) patients. There was complete agreement between observers for all items on endoanal MR images, except for the presence of secondary fistula extensions (agreement, 90%; kappa, 0.74). History of obstetric trauma, pelvic floor surgery, or Crohn disease was present in 10 (50%) patients. Of these patients, six (60%) had a complex anovaginal fistula and four (40%) had a simple anovaginal fistula. In the remaining 10 patients without relevant medical history, one (10%) had a complex anovaginal fistula. This difference tended toward statistical significance (P =.057).

CONCLUSION

Endoanal MR imaging allows evaluation of anovaginal fistulas and additional abnormalities, such as abscesses within the rectovaginal septum, secondary perianal fistula tracts, and sphincter damage.

Rectovaginal fistula

Rectovaginal fistulas present a distressing problem for the patient and a challenge for the treating physician. Successful management must take into consideration the etiology of the fistula and the health of both the rectum and the patient. Obstetrical fistulas can be treated successfully by local approaches transanally or transvaginally. Episioproctotomy may be considered if there is an associated sphincter defect. Crohn's related fistulas usually require proctectomy if the rectum is severely involved. Local repair can be considered in instances where the rectum is relatively healthy and local sepsis has been controlled. Radiation-induced fistulas may be secondary to cancer recurrence, which must be excluded. If the patient is not a candidate for a radical resectional approach, fecal diversion alone should be performed.

Reliability of endosonography in evaluation of anal fistulae and abscesses

OBJECTIVE

To assess the reliability of anal endosonography (AES) in the diagnosis of anal fistulae and abscesses.

MATERIAL AND METHODS

86 patients with different types of anal fistulae and abscesses were prospectively examined with a 7.0 MHz transducer. Type of anal fistulae, differentiation between simple and complex tracts, and location of their internal openings were defined. In 66 cases with permeable external opening, hydrogen peroxide solution was introduced into the fistula tract. Reliability of AES was defined after surgical treatment of all cases.

RESULTS

74 anal fistulae, including 43 transsphincteric, 11 intersphincteric, 6 suprasphincteric, 3 superficial, and 11 ano-vaginal were found on AES. 27 fistulae were complex, and 47 simple fistulae. In 10 patients a coexisting abscess was found; the remaining 12 abscesses were without any fistula. Surgery confirmed the type of anal fistula in 64 patients (86.5%), and location of internal openings in 60 cases (81.1%). All abscesses were confirmed.

CONCLUSION

AES showed high accuracy in diagnosing anal fistulae and abscesses.

Acquired gastrointestinal fistulas: classification, etiologies, and imaging evaluation

Fistulas are abnormal communications between two epithelial-lined surfaces. Gastrointestinal fistulas encompass all such connections that involve the alimentary tract, and they can be congenital or acquired in nature. This review focuses on acquired gastrointestinal fistulas. Development of an acquired gastrointestinal fistula can greatly affect patient outcome, yet the clinical manifestations are often protean in nature and the etiology, elusive. Imaging plays an important role in the detection and management of acquired gastrointestinal fistulas. The more routine use of cross-sectional imaging (especially computed tomography and magnetic resonance imaging) has altered the standard sequence of radiologic evaluation for possible fistulas, but fluoroscopic studies remain a valuable complement, especially for confirming and defining the anomalous communications. In this review, a classification scheme for gastrointestinal fistulas is provided, major causes are discussed, and individual fistula types are elaborated with an emphasis on contemporary imaging approaches.

Anovaginal and rectovaginal fistulas: endoluminal sonography versus endoluminal MR imaging

OBJECTIVE

The exact location of anovaginal and rectovaginal fistulas cannot be determined by physical examination and conventional techniques. The objective of our study was to compare the accuracy of endoluminal sonography and endoluminal MR imaging in revealing the location of anovaginal and rectovaginal fistulas.

MATERIALS AND METHODS

Nineteen consecutive patients (age range, 28-56 years; median age, 39 years) with clinical indications of an anovaginal or rectovaginal fistula were included in our retrospective study. Endoluminal sonography was performed using a 7.5-MHz transducer. Endoluminal MR imaging was performed at 0.5 T for 10 patients and 1.5 T for nine patients; axial T2-weighted gradient-echo, coronal and sagittal T2-weighted turbo spin-echo (0.5 T), or axial and radial T2-weighted turbo spin-echo and axial T2-weighted fat saturated turbo spin-echo (1.5 T) images were obtained. For a variety of reasons, surgery of the fistula was not attempted in six of these 19 patients. The imaging findings were compared with the findings obtained during surgery in the remaining 13 patients.

RESULTS

In 12 of the 13 patients, the fistula was found during surgery: seven of the fistulas were anovaginal, and five were rectovaginal. Findings of endoluminal sonography were true-positive in 11 patients, true-negative in one, and false-negative in one. Findings of endoluminal MR imaging were true-positive in 11 patients, false-negative in one, and false-positive in one. Positive predictive value for endoluminal sonography and endoluminal MR imaging were 100% and 92%, respectively. Imaging findings for anal sphincter defects were comparable.

CONCLUSION

Endoluminal sonography and endoluminal MR imaging have comparable positive predictive values in revealing the location of anovaginal and rectovaginal fistulas.

Endosonography of anal canal diseases

Anal endosonography became a valuable imaging method for diagnosis of anal diseases because of its accessibility, relative simplicity of performance, and low cost. It is used most often to detect anal sphincter defects, to classify anal fistulas and perianal abscesses, and to stage anal tumors. This review presents a normal anatomy of the anal canal, examination technique, and normal endosonographic anatomy of anal sphincters. The endosonographic findings of anal sepsis, malignancy, trauma, abnormalities in Crohn disease, and ulcerative colitis, as well as the role for anal endosonography among other imaging modalities, are discussed.

Contrast-enhanced endosonography for the diagnosis of anal and anovaginal fistulas

PURPOSE

We assessed whether contrast-enhanced anal endosonography (AES) with hydrogen peroxide improves the identification of anal fistulas and their internal openings compared with non-contrast AES.

METHODS

The study group comprised 12 patients who had various types of anal fistulas with visible external openings. AES was performed before and about 15 seconds after injection of 1 ml of 3% hydrogen peroxide into the fistula tract through the external opening.

RESULTS

Both contrast and non-contrast AES revealed 7 transsphincteric, 2 intersphincteric, 1 suprasphincteric, and 2 anovaginal fistulas. Simple tracts were found in 8 cases and complex tracts in 4 cases on non-contrast AES. Contrast-enhanced AES revealed 9 simple and 3 complex fistulas. One fistula that appeared complex on the non-contrast study appeared simple after contrast agent administration. Contrast-enhanced AES demonstrated more internal openings than non-contrast AES did. Surgery confirmed 11 of the fistulas; an internal opening could not be located surgically for the other tract.

CONCLUSIONS

Contrast-enhanced AES appears to be superior to non-contrast AES in the preoperative assessment of anal and anovaginal fistulas and in demonstrating and locating their internal openings.

Vaginal reconstruction/fistulae

Vaginal reconstruction is required in congenital absence of the vagina in the paediatric population and in patients with surgical (anterior exenteration) or traumatic loss of the vagina. Although vaginal agenesis is rare, its description and attempts at replacement vaginoplasty date back to antiquity. Different forms of vaginal reconstruction are described, including the use of split-thickness or full-thickness grafts, amnion, peritoneum or bowel. Experience with bowel segments for vaginoplasty, with few complications and high success rates, have expanded the indications for this technique, rendering it of great importance in the field of vaginal reconstruction, especially when large bowel segments are utilized. Most vaginal fistulae occur after gynaecological surgery. There is a multitude of established techniques for closure of vaginal fistulae with comparable success rates, and two different approaches (vaginal or abdominal) may be used. Preferable for complicated or recurrent fistulae is the abdominal approach because a well vascularized pedicled omentum majus flap can be interposed. Postirradiation fistulae, although rare, represent a challenge for the reconstructive surgeon. Fistula excision and closure fails in a high percentage of patients, and in cases of additional bladder and vaginal shrinkage urinary continence can only be achieved by urinary diversion.

Manometric squeeze pressure difference parallels functional outcome after overlapping sphincter reconstruction

PURPOSE

This study was designed to evaluate the effectiveness of overlapping anal sphincter reconstruction and to determine the manometric parameters that correlate with a successful functional outcome.

METHODS

A retrospective review of patients who had undergone overlapping sphincter reconstruction for anal incontinence from 1988 to 1999 was undertaken. Only patients with preoperative and six-months-postoperative anal manometry were included in this study. Standard statistical tests were used to compare pre- and postoperative findings.

RESULTS

A total of 52 overlapping sphincter reconstructions were performed on 49 patients (46 females). The mean age was 44 (+/- standard error, 15.8; range, 20-81) years, with follow-up at six months. Forty-two patients had a history of complicated vaginal delivery (episiotomies, tears, forceps delivery); 36 patients had a history of anal or perineal surgery; and two patients had perianal Crohn's disease. Nine patients (17 percent) had undergone prior sphincter repair. Incontinence grade improved in 37 patients (71 percent), and complete continence returned in 21 patients (40 percent). The presence of a rectovaginal fistula, postoperative complications, previous sphincter repair, and increase in pudendal nerve terminal motor latency did not affect functional outcome (P = not significant). Patients older than 50 years had a better functional outcome than their younger counterparts after sphincter repair (P = 0.02). Although mean maximal squeeze pressure and mean anal sphincter length increased significantly after sphincter reconstruction (P = 0.0006 and 0.004, respectively), only squeeze pressure difference correlated with functional outcome (r = 0.37; P = 0.007).

CONCLUSIONS

Overlapping sphincter reconstruction improved anal function in the majority of patients. The most important factor in the return to normal sphincter function is an increase in squeeze pressure.