Accuracy of hydrogen peroxide enhanced endoanal ultrasonography in assessment of the internal opening of an anal fistula complex

A Simple Protocol to Effectively Manage Anal Fistulas with No Obvious Internal Opening

Purpose

In some anal fistulas, the internal/primary opening cannot be located even after examination and assessment on MRI or transrectal ultrasound. The efficacy of a simple new protocol to manage such therapeutically challenging fistulas was tested.

Patients and Methods

All anal fistula patients operated consecutively over 7 years were included in the study. A simple two-step protocol was followed for fistulas in which the internal opening was not locatable after clinical examination and MRI assessment. First, the MRI was reassessed. The site where the fistula was closest to the internal sphincter was noted. It was assumed that the internal-opening was located at that position and the fistula was treated accordingly. Second, in horseshoe anal fistulas with no apparent internal opening, it was assumed that the internal opening was located in the midline. Low fistulas were treated by fistulotomy and high fistulas by a sphincter-sparing procedure. Incontinence was evaluated by objective incontinence scores (Vaizey scores).

Results

A total of 757 patients were operated (median follow-up-33 months). Of these, 57 patients were excluded due to short or inadequate follow-up. In 154/700 (22%) patients, the internal opening could not be located while in 546/700 (78%), the internal opening was found. Both the groups were similar in all parameters. In the "internal-opening found" group, the fistula healed completely in 486/546 (89%) and in the 'internal-opening not found group', the fistula healed in 140/156 (90.9%) (p=1.01). The objective continence scores did not change significantly after surgery in both the groups.

Conclusion

This new protocol seems effective as a high cure rate could be achieved in 'internal-opening not found' fistulas which was comparable to fistula healing in the 'internal-opening found' group.

Updates on the diagnostic tools for evaluation of pelvic floor disorders

PURPOSE OF REVIEW

Pelvic floor disorders are common and cause significant morbidity for women. Recent advances in the evaluation of women with pelvic floor dysfunction have improved diagnostic accuracy and, with the development and use of validated patient-reported outcomes, has improved measurement of outcomes important to patients. We describe recent advances in the evaluation and measurement of pelvic floor disorders (PFDs).

RECENT FINDINGS

We describe recent developments in pelvic floor assessment of women with pelvic floor dysfunction.

SUMMARY

Complex integration of multiple anatomic structures and their function are necessary for pelvic floor function. Although the pillars of a complete assessment are a thorough history and physical exam, diagnostic tools can aid in fleshing out the correct and complete analysis of the patient suffering from PFDs.

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.

Peroxide-enhanced endoanal ultrasound in preoperative assessment of complex fistula-in-ano

BACKGROUND

In complex fistula-in-ano, preoperative imaging can help identify secondary tracts and abscesses that can be missed, leading to recurrence. We evaluated hydrogen peroxide-enhanced endoanal ultrasound (PEEUS) in the characterization of fistula compared with standard clinical and operative assessment.

METHODS

Patients with complex fistula-in-ano treated between February 2008 and May 2009 at our institution were prospectively evaluated by PEEUS with recording of the preoperative clinical examination and intraoperative details of the fistula. Of the 135 patients with fistula-in-ano, 68 met the inclusion criteria for complex fistula-in-ano. Correlation of clinical findings and PEEUS to the gold standard intraoperative findings was assessed in characterizing the fistula. The percent agreement between the clinical and PEEUS findings against the gold standard was derived, and the kappa statistic for agreement was determined.

RESULTS

The mean age of the cohort was 42.54 ± 10.86 years. The fistula tracts were curvilinear, high, and transsphincteric in 16 (23.53%), 8 (11.76%), and 42 (61.76%) patients, respectively. Secondary tracts and associated abscess cavities were seen in 28 (33.82%) and 35 (51.47%) patients, respectively. PEEUS correlated better than clinical examination with regard to site (92.65 vs 79.41%; p < 0.001) and course (91.18 vs 77.94%; p < 0.001) of secondary tract and associated abscesses (89.71 vs 80.88%; p = 0.02). There was a trend of better correlation of PEEUS compared to clinical examination in classifying the primary tract as per Park's system (88.24 vs 79.41%; p = 0.06), but it did not reach statistical significance. PEEUS and clinical examination were comparable in correlation of the level of the primary tract (kappa: 0.86 vs 0.78; p = 0.22) and the site of internal opening (kappa: 0.97 vs 0.89; p = 0.22). The operative decision was changed in 13 (19.12%) subjects based on PEEUS findings.

CONCLUSIONS

PEEUS is a feasible and efficient tool in the routine preoperative assessment of complex fistula-in-ano.

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.

Anography: a technique for determining the location of the internal opening in perianal fistula

AIM

Anography is a radiological investigation for fistula-in-ano that identifies the primary fistula track through the internal opening. The efficacy of anography as a radiological method of identifying the location of the internal opening was investigated.

METHOD

A retrospective study of 50 patients with a clinical diagnosis of fistula-in-ano of criptoglandular aetiology was performed. During anography, the location of the internal opening was recorded with respect to the quadrant of anal canal and distance from the anal verge. These data were compared with the findings during examination under anaesthesia (EUA), which was used as the gold standard for the identification of the internal opening.

RESULTS

The sensitivity of anography for identifying a patent internal opening was 91% and specificity 100%. There was complete agreement between anography reports and findings at EUA regarding the quadrant of anal canal in which the internal opening was located. In more than 90% of patients, the internal opening was found at EUA within 1 cm from the site described on anography.

CONCLUSION

Anography is an accurate test for predicting the exact quadrant of the anal canal in which the internal opening is located, as well as the distance of the internal opening from the anal verge. This inexpensive and simple radiological investigation should be the test of first choice in the evaluation of patients with fistula-in-ano when difficulty is anticipated in identifying the internal opening.

[Comparison of hydrogen peroxide-enhanced ultrasound with surgery in the diagnosis of perianal fistulas]

PURPOSE

To evaluate the usefulness of hydrogen peroxide-enhanced ultrasound (H(2)O(2)) in the preoperative assessment of perianal fistulas and to compare these results with unenhanced ultrasound findings.

METHODS

All patients with surgically confirmed perianal fistula who underwent preoperative enhanced and unenhanced ultrasound were included. We compared enhanced and unenhanced ultrasound findings with surgical results (chi(2) and McNemar tests).

RESULTS

A total of 44 surgically treated patients were analysed. Hydrogen peroxide-enhanced ultrasound correctly identified primary fistula tracks in 34 patients (sensitivity of 77%), 100% of abscesses and the internal opening in 29 out of 37 identified with surgery (sensitivity of 78% and specificity of 70%). The use of hydrogen peroxide provided additional information to the ultrasound performed without the use of contrast enhancement in 32 of the 44 patients (73%). H(2)O(2) increased the number of fistula tracts correctly detected (77% vs 45%; p<0.003), particularly suprasphincteric fistulas, as well as internal openings (78% vs 22%; p<0.001) and secondary tracks (70% vs 0%). Additional detection of fistula tracks after H(2)O(2) injection was higher in patients with previous surgery (68% vs 35%; p<0.05).

CONCLUSIONS

Hydrogen peroxide-enhanced ultrasound shows good agreement compared with surgical findings in the assessment of perianal fistulas. H(2)O(2) improves conventional ultrasound results, increasing the detection of fistula tracks and internal openings, and also providing additional information, particularly in previously operated patients.

Comparison of accuracy of physical examination and endoanal ultrasonography for preoperative assessment in patients with acute and chronic anal fistula

BACKGROUND

This study was undertaken to evaluate the accuracy of endoanal ultrasonography for preoperative assessment of anal fistula, with special reference to the difference between acute and chronic fistula.

METHODS

The subjects comprised 401 patients treated for acute or chronic anorectal sepsis of cryptoglandular origin during the period January through December 2005. All patients underwent physical examination and endoanal ultrasonography. Agreement between the physical and endosonographic findings and the definitive surgical findings were evaluated with special reference to classification of the primary tract and horseshoe extension and localization of the internal opening. The difference in accuracy of endosonographic assessment between acute and chronic fistula was also evaluated.

RESULTS

The accuracy of endoanal ultrasonography was significantly higher than that of physical examination in detecting the primary tract (88.8% vs. 85.0%, p=0.0287) and horseshoe extension (85.7% vs. 58.7%, p<0.0001) and in localizing the internal opening (85.5% vs. 69.1%, p<0.0001). Furthermore, localization of the internal opening by endosonography was significantly more accurate in chronic fistula than in acute fistula (89.5 % vs. 76.8%, p<0.0001), although the accuracy in detecting the primary tract and horseshoe extension was not significantly different.

CONCLUSIONS

Endoanal ultrasonography is reliable and useful for preoperative assessment of anal fistula, particularly for detecting horseshoe extension and localizing the internal opening. Endosonographic assessment provides clearer depiction of the internal opening during periods of quiescence than during the period of abscess formation. For patients with acute anorectal sepsis, initial surgical drainage and subsequent fistula surgery, rather than one-stage fistula surgery, may be advisable to avoid misidentification of the internal opening.

Prognostic value of endoanal ultrasound for fistula-in-ano: a retrospective analysis

PURPOSE

This study was designed to assess whether preoperative endoanal ultrasound plays a prognostic role in the surgical outcome of anal fistula.

METHODS

A retrospective review was conducted at a single institution.

RESULTS

Sixty-nine patients underwent 83 studies. Indications for endoanal ultrasound included complex fistulas and tracts, multiple external openings, recurrent fistulas, and/or failed previous surgical intervention. Mean age was 51.7 years. Fifty-three patients (77 percent) were men. Mean duration of symptoms was 3.1 years. Forty-nine patients (71 percent) had undergone previous surgical intervention to eradicate sepsis or fistula. Sixty patients (87 percent) underwent surgical interventions and were divided into two groups: Group A (73.3 percent), concordance with ultrasound findings; and Group B (26.7 percent), nonconcordance. Mean follow-up in the surgical group was 15.6 months. Measured outcome was total number of operations per patient and failure rate of primary surgical intervention. No difference was noted in mean total number of operations between Group A (1.57) and Group B (1.69) (P = 0.71). There was a statistically nonsignificant trend toward a higher failure rate of the primary intervention in the nonconcordance group [failure rate 18.2 percent in Group A vs. 25 percent in Group B (P = 0.72)].

CONCLUSIONS

The findings and accuracy of preoperative endoanal ultrasound did not influence postoperative outcome.