MR Imaging of Perianal Fistulas: A Review of Fundamentals, Complications, and Post-Therapy Imaging

MR imaging is the gold standard for diagnosis, providing detailed evaluation of perianal fistulas. MR imaging aids in detecting, classifying, and monitoring fistulas and guiding treatment. Detailed radiology reports, incorporating patient history and disease-specific considerations, are essential for effective management and improved clinical outcomes. This review overviews fundamental high-yield concepts to aid radiologists in interpreting MR imaging for perianal fistulas with multiple case examples.

Oncologic surgical complications: Imaging approach and characteristics

Cancer is a disease that has multisystemic facets in its diagnosis and management. The treatment of choice with curative intent in many sites is surgery for early disease, commonly combined with neoadjuvant or adjuvant treatment. Oncologic surgery can have both locoregional and systemic complications, occasionally accentuated by multimodality treatment. While complications are of concern in any surgical setting, they may have specific intricate implications in the care of a cancer patient. Diagnostic imaging provides a non-invasive means of detecting complications and communicating the findings to the rest of the team for decision-making. Clinical clues, site-specific considerations and visual characteristics can aid the radiologist in arriving at a diagnosis of a locoregional oncologic surgical complication. Knowledge of systemic or distant complications, their clinical and imaging characteristics is a must-know following oncologic surgery. This article as an educational narrative review addresses imaging approach and characteristics of oncologic surgical complications, by pairing clinical considerations and imaging aspects.

[Rectovaginal fistulas : Differentiated diagnostics and treatment]

Rectovaginal fistulas (RVF) represent less than 5% of anorectal fistulas. The classification of RVF is based on the localization (low vs. high) and the etiology. The most frequent causes of RVF are birth trauma, Crohn's disease, previous surgery and pelvic irradiation. In most cases a clinical diagnostic assessment is sufficient. Additionally, endosonography is a reliable tool to detect sphincter defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are reserved for special situations (e.g., RVF related to anastomotic leakage, after pelvic irradiation or associated with complex perianal fistulizing Crohn's disease). The surgical treatment is primarily oriented to the localization and etiology. Surgical techniques range from local procedures (e.g., endorectal advancement flap repair, transvaginal or transperineal closure) up to more invasive tissue interposition (e.g., bulbocavernosus muscle fat tissue flap or transposition of the gracilis muscle). In "high" RVF transabdominal approaches such as coloanal anastomosis, pull through procedures or omental interposition are indicated. All surgical procedures show high recurrence rates. Several operations are mostly necessary and a stoma creation is often required.

Current update on the role of endoanal ultrasound: a primer for radiologists

Endoanal ultrasound (EAUS) is a valuable imaging modality for the evaluation of anal and perianal pathologies. It provides detailed information about the anatomy and physiology of the anorectal region and has been used in pre-and post-operative settings of anorectal pathologies. EAUS is not only useful in the evaluation of benign pathologies but also in loco-regional staging of anal and rectal tumors. EAUS has several advantages over MRI, including reduced cost, better patient tolerance, and improved scope of application in patients with contraindications to MRI. Despite its benefits, EAUS is not widely performed in many centers across the globe. This article aims to educate radiologists, trainees, and surgeons about the indications, contraindications, patient preparation, imaging technique, and findings of EAUS. We will also highlight the technical difficulties, diagnostic challenges, and procedural complications encountered during EAUS, along with a comparative analysis of EAUS with other imaging approaches.

[Postoperative Imaging Findings of Colorectal Surgery: A Pictorial Essay]

Postoperative colorectal imaging studies play an important role in the detection of surgical complications and disease recurrence. In this pictorial essay, we briefly describe methods of surgery, imaging findings of their early and late complications, and postsurgical recurrence of cancer and inflammatory bowel disease.

Synchronous radiation-induced enterovesical and enterocervical fistulas in carcinoma of the uterine cervix

Radiation-induced fistulas (RIF) are uncommon therapeutic complications of radiotherapy in patients treated for carcinoma of the uterine cervix. Synchronous occurrence of enterocervical and enterovesical fistulas secondary to radiation is extremely rare and previously unreported in the literature. We report a case of synchronous enterovesical and enterocervical fistulas in a patient with carcinoma of the cervix treated using chemotherapy and radiation along with a brief overview of etiopathogenesis of RIF.

MRI of the ileal pouch

Ileal pouch surgery is the surgical gold standard treatment for patients with ulcerative colitis (UC) and familial adenomatous polyposis (FAP). However, ileal pouch surgery is a technically challenging procedure and is associated with high morbidity. Clinical presentations of pouch complications are often nonspecific but imaging can identify many of these complications and is essential in clinical management. This paper will focus on magnetic resonance imaging (MRI) of the ileal pouch, including recommended MRI protocol and approach to imaging interpretation with an emphasis on those ileal pouch complications particularly well evaluated with MRI.

Gynecological Fistulae-Has Anything Changed in the Diagnosis and Treatment over the Last Decade? A Narrative Literature Review

Gynecological fistulae are a rare but severe complication of radiation therapy, pelvic surgery, prolonged labor, cesarean deliveries, or inflammatory bowel diseases. A gynecological fistula is an abnormal pathway formed between the urinary and gynecological tract, most commonly located between the urinary bladder and vagina. Vesico-uterine and vesicovaginal fistulae are an important health issue, common in women of reproductive age in developing countries with limited access to obstetrical care. Various surgical techniques have been described for VVF repair, depending on the location, severity, and cause of the fistula and the surgeon's experience. The purpose of our review was to evaluate the present state of knowledge about the prevalence and treatment of gynecological fistulae. The PubMed scientific database was searched for original articles on the subject of gynecological fistulae that had been published between 2013 and 2023.

Post-Surgical Imaging Assessment in Rectal Cancer: Normal Findings and Complications

Rectal cancer (RC) is one of the deadliest malignancies worldwide. Surgery is the most common treatment for RC, performed in 63.2% of patients. The type of surgical approach chosen aims to achieve maximum residual function with the lowest risk of recurrence. The selection is made by a multidisciplinary team that assesses the characteristics of the patient and the tumor. Total mesorectal excision (TME), including both low anterior resection (LAR) and abdominoperineal resection (APR), is still the standard of care for RC. Radical surgery is burdened by a 31% rate of major complications (Clavien-Dindo grade 3-4), such as anastomotic leaks and a risk of a permanent stoma. In recent years, less-invasive techniques, such as local excision, have been tested. These additional procedures could mitigate the morbidity of rectal resection, while providing acceptable oncologic results. The "watch and wait" approach is not a globally accepted model of care but encouraging results on selected groups of patients make it a promising strategy. In this plethora of treatments, the radiologist is called upon to distinguish a physiological from a pathological postoperative finding. The aim of this narrative review is to identify the main post-surgical complications and the most effective imaging techniques.

Tumor-Bowel Fistula as a Rare Form of Recurrent Ovarian Cancer-Imaging and Treatment: Preliminary Report

BACKGROUND

The aim of this pilot study was to evaluate the value of imaging techniques, including computed tomography (CT) and magnetic resonance imaging (MRI), in the diagnosis of a tumor-bowel fistula as a rare form of epithelial ovarian cancer (EOC) relapse. We also performed an initial assessment of the effectiveness of the treatment of this form of relapse.

METHODS

The study group consisted of eight patients with suspected platinum-sensitive recurrence in the form of a tumor/bowel fistula. All patients finished their first line of chemotherapy and subsequently showed complete remission for 6 months or more. To qualify patients for further treatment, CT and MRI were performed, which suggested the presence of a fistula between the recurrent tumor and intestine. DESKTOP study criteria were used to qualify patients for secondary cytoreduction. Second-line chemotherapy was given after secondary debulking.

RESULTS

In all patients, fistulas formed between the tumor and large bowel. On CT, the fistulas were indirectly visible. In all cases, the fistula was visible on MR images, which showed hypointensity on the T2 and T1 post-contrast sequences but did not show restricted diffusion on the diffusion-weighted imaging (DWI) sequence. Patients who were qualified for the study underwent secondary debulking with bowel resection. In all eight cases, the fistula between the tumor and surrounding organs was confirmed. During surgery, seven intestinal anastomoses and one colostomy were performed. No residual macroscopic tumor remained in seven cases (resection R0-87.5%). The progression-free survival (PFS) was 8.4-22.6 months (median 13.4). In the group with cytoreduction R0, the median PFS was 15.5 months (12-22).

CONCLUSION

In patients with suspected EOC recurrence with clinically suspected fistula, CT scan is not sufficient. In CT, the presence of a fistula is suspected based on indirect symptoms. MRI, as a method with much greater tissue resolution, confirms the diagnosis. In addition, MRI can identify the point of the tumor/bowel junction. This is especially true with a large infiltration covering several intestinal parts. Bowel resection with simultaneous anastomosis is a good and safe solution for these patients. However, appropriate qualification for the procedure is necessary, which will allow for surgery without residual macroscopic disease (R0 surgery). Due to the small number of cases, our results cannot be generalized. We treat them as a hypothesis that can be verified in a larger study.

Comparison of contrast-enhanced fat-suppressed T1-3D-VIBE and T1-TSE MRI in evaluating anal fistula

OBJECTIVE

To evaluate the accuracy of contrast-enhanced (CE) fat-suppressed three-dimensional (3D) T1-weighted imaging with volumetric interpolated breath-hold examination (FS-T1-3D-VIBE) and fat-suppressed T1-weighted turbo spin echo (FS-T1-TSE) sequence in characteristics of anal fistula.

METHODS

One hundred and two patients underwent perianal CE-MRI examination on a 3T scanner including FS-T1-3D-VIBE and FS-T1-TSE sequences before surgery. The performance of each sequence was evaluated in terms of fistula classification, clarity of internal opening, number and position of internal openings including the distance between internal opening and anal verge, presence of secondary tracts and blind-ending sinus tracts. MRI findings were compared with surgical findings. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of fistula, gluteus maximus, and subcutaneous fat were compared between CE FS-T1-TSE and CE FS-T1-3D-VIBE.

RESULTS

Compared with CE FS-T1-TSE, CE FS-T1-3D-VIBE displayed more accurate in secondary tract, lithotomy position of the internal opening and the distance between internal opening and anal verge (P < 0.05). CE FS-T1-3D-VIBE was found superior to CE FS-T1-TSE in the clarity of the internal openings and in the diagnostic accuracy of blind-ending sinus tracts and complex fistulas in Standard Practice Task Force classification (P < 0.05). CE FS-T1-3D-VIBE achieved higher SNRs and CNRs in fistula and gluteus maximus than CE FS-T1-TSE (P ≤ 0.001).

CONCLUSION

CE-MRI of FS-T1-3D-VIBE might be a more valuable noninvasive technique than FS-T1-TSE to evaluate the anal fistula on evaluating the lithotomy position of internal opening, distance between internal opening and anal verge, clarity of internal opening, secondary tract, blind-ending sinus tract and classification of the complex fistula. The trial registration number for this prospective trial was Chi-TR1800020206 and the trial registration date was December 20, 2018.

Surgical treatment of deep-lying ano-/rectovaginal fistulas using a de-epithelialized “Singapore flap” (pudendal thigh flap)

Background

Rectovaginal fistulas represent 5% of all anorectal fistulas. For affected women, this pathology is associated with a reduction in quality of life (QoL) and self-esteem. Most commonly used methods of surgical closure have high recurrence rates or permanent perineal complaints, which in turn lead to negative effects on QoL and self-esteem. A fistula closure, using the “de-epithelialized Singapore flap” (SF), can be a good alternative therapy strategy.

Method

Our retrospective case series processes the long-term results of seven patients who were operated on for ano-/rectovaginal fistula using the SF. All patients underwent surgery at the University Hospital Graz, between May 2012 and July 2015. The data of the surgical follow-up examinations were collected and an additional telephone survey was carried out. The procedure is presented based on a structured description. All procedures were performed jointly by the Department of General Surgery and the Department of Plastic Surgery.

Results

The average age of the seven patients was 46.14 years (23–72 a). Five patients had a total of 12 previous operations with frustrating results. Of the seven patients treated, six had a permanent fistula closure (85.7%). The results of the telephone survey (n = 6) showed a high level of patient satisfaction (100%), and an improvement in QoL (83.3%), through our surgical method. In our cohort, neither urinary nor fecal incontinence occurred.

Conclusion

The treatment of an ano-/rectovaginal fistula using the “de-epithelialized pudendal thigh flap” (Singapore flap) is a promising treatment alternative. In particular, patients who have had previous proctological interventions show a benefit from this procedure.

Trans-vaginal repair of recurrent rectovaginal fistula with interposition of BIO-A Tissue Reinforcement

Rectovaginal fistulas (RVFs) represent the majority of all symptomatic leakages after anterior and low anterior resection in women. Conservative management is useful in paucisymptomatic patients with small fistulas but is usually unsuccessful in all other cases. The surgical strategies are various and heavily dependent on the type and extent of anatomic involvement. We present a case of a 51-year-old female with a multi-recurrent rectovaginal fistula that occurred since a laparoscopic sigmoidectomy was performed for a complicated diverticular disease in May 2015. An attempt to close the fistula was undertaken three times. In July 2019, a transvaginal repair was performed with interposition in the rectovaginal septum of GORE^® BIO-A^® Tissue Reinforcement. The postoperative course was uneventful. There was no recurrence and functional outcome was good at 24-months follow-up. Rectovaginal fistula can be successfully treated using the interposition of a GORE^® BIO-A^® Tissue Reinforcement with significant economic savings and good functional outcomes even through a transvaginal approach. It represents a therapeutic option for an otherwise difficult-to-treat complex fistula.

Female Pelvic Fistulae

Female pelvic fistulae are a pathologic connection between the urinary or gastrointestinal tract and the genital tract. Although this condition has been present for millennia, successful surgical treatments have only been described for the past few hundred years. In developed nations, the most common cause of genitourinary fistulae is benign gynecologic surgery, but worldwide it is obstetric trauma. Fistulae management is rooted in surgical intervention with the highest probability of success associated with the first repair.

Rectovaginal Fistula Repair 1 Year Later: Lessons Learned

INTRODUCTION

Rectovaginal (RV) fistulas are notoriously difficult to treat. Various methods for repair exist, and refinements in techniques can lead to "successful" outcomes. Review of the literature demonstrates that outcomes studies are scarce and mostly limited to comments on closure rate. We have experienced "success" in our own series with 100% closure rate, regardless of fistula etiology and comorbidities (radiation, inflammation, etc). However, long-term outcomes, including various complications and quality of life changes, have previously been underreported.

METHODS

Critical analysis of various outcomes after fistula repair in 14 patients was performed. Patients were surveyed and interviewed with regard to problems before and after fistula repair to obtain objective data focusing on their experience and outcomes. Conclusions are based on physician assessment and patient surveys 1 year after fistula repair and at least 6 months after ostomy reversal and are discussed within the context of data from the literature.

RESULTS

Overall satisfaction rate after repairs was high. All patients would undergo attempt at repair again regardless of complications or functional changes (not present before repair). After repair, sexual dyspareunia affected 5 patients (36%); however, most abstained from sexual activity when their RV fistula became apparent. No patient admitted to dyspareunia before the development of their RV fistula. Anal sphincter and defecation function, as well as stool continence, were judged by surgeons and patients uniformly as adequate. However, 3 patients (21%) complained of intermittent problems with urination. A new/different type of pain affected 2 of 4 patients with Crohn disease. One of these patients subsequently developed a new postsphincteric RV fistula. Another patient noted new intermittent vaginal discharge after ostomy reversal, and magnetic resonance imaging suggested a residual fistula, which was not seen on follow-up sigmoidoscopy and "Blue Dye Test."

CONCLUSIONS

We previously reported on algorithms for repair and refinements in techniques for "successful" repair of RV fistulas with zero recurrence rate. Long-term follow-up indicates, however, that although the overall satisfaction rate after surgery is high, true "success," defined as permanent fistula closure, is not necessarily problem free. Long-term morbidity and the management of other unique sequelae and problems are underreported.

Imaging of the Vagina: Spectrum of Disease with Emphasis on MRI Appearance

The vagina is a median fibromuscular structure of the female reproductive system that extends from the vulva inferiorly to the uterine cervix superiorly. As most vaginal lesions are detected at gynecologic examination, imaging performed for nongynecologic indications can frequently cause concomitant vaginal pathologic conditions to be overlooked. The vagina is often underevaluated at routinely performed pelvic transvaginal US because of a narrow scan area and probe positioning. MRI has progressively become the imaging method of choice for vaginal pathologic conditions, as it provides excellent soft-tissue detail with unparalleled delineation of the complex pelvic floor anatomy and helps establish a diagnosis for most vaginal diseases. It is important that radiologists use a focused approach toward understanding and correctly recognizing different vaginal entities that may otherwise go unnoticed. In this case-based review, the authors discuss the key imaging features of wide-ranging vaginal pathologic conditions, with emphasis on appearance at MRI. Knowledge of vaginal anatomy and embryology is helpful in evaluating congenital anomalies at imaging. Often seen incidentally, vaginal inflammation can cause diagnostic confusion. Because of its central location in the pelvis, the vagina can form fistulas to the urinary bladder, colon, rectum, or anus. Vaginal masses can be neoplastic and nonneoplastic and include a myriad of benign and malignant conditions, some of which have characteristic imaging features. Therapeutic and nontherapeutic vaginal foreign bodies include pessaries, vaginal mesh, and packing that can be seen with or without associated complications. Online supplemental material is available for this article. ^©RSNA, 2021.

Postoperative complications of colorectal cancer

Colorectal cancer is the third most common cancer, and surgery is the most common treatment. Several surgical options are available, but each is associated with a range of potential complications. The timely and efficient identification of these complications is vital for effective clinical management of these patients in order to minimise their morbidity and mortality. This review aims to describe the range of commonly performed surgical treatments for colorectal surgery. In addition, frequent post-surgical complications are explored with investigative options explained and illustrated.

Changing Paradigms in the Management of Acute Uncomplicated Diverticulitis

Left-sided colonic diverticulitis is a common condition with significant morbidity and health care costs in Western countries. Acute uncomplicated diverticulitis which is characterized by the absence of organ dysfunction, abscesses, fistula, or perforations accounts for around 80% of the cases. In the last decades, several traditional paradigms in the management of acute uncomplicated diverticulitis have been replaced by evidence-based routines. This review provides a comprehensive evidence-based and clinical-oriented overview of up-to-date diagnostics with computer tomography, non-antibiotic treatment, outpatient treatment, and surgical strategies as well as follow-up of patients with acute uncomplicated diverticulitis.

Allogeneic expanded adipose-derived stem cells in the treatment of rectovaginal fistulas in Crohn's disease

AIM

Crohn's disease (CD)-related rectovaginal fistulas (RVFs) are rare, challenging to treat and associated with a high morbidity. Due to a significant lack of data, we aimed to analyse the safety and feasibility of allogeneic adipose-derived stem cells (ASCs) in the treatment of CD-related RVF.

METHOD

Four consecutive patients with CD-related RVF underwent treatment with expanded allogeneic ASCs extracted from a healthy donor in a tertiary referral centre in 2019. None of the patients had an intestinal diversion at the time of the treatment. Follow-up was performed 6 months postoperatively.

RESULTS

The median operation time was 45 min with a median hospital stay of 3 days. No intra-operative complications occurred. Three patients (75%) developed recurrent RVF after a median follow-up of 19 days. Two patients required surgical treatment including loose seton drainage due to discharge and pain. One patient developed recurrence of symptoms after 10 days, but refused further surgical therapy. Only one patient (25%) showed healing of the RVF, with re-epithelialization of both the vaginal and rectal opening and absence of clinical symptoms.

CONCLUSION

Expanded allogeneic ASC therapy represents a novel safe treatment option for CD-associated RVF. Although efficacy appears limited, further controlled studies are required to draw robust conclusions.

Rectovaginal Fistulas Secondary to Obstetrical Injury

Rectovaginal fistula (RVF), defined as any abnormal connection between the rectum and the vagina, is a complex and debilitating condition. RVF can occur for a variety of reasons, but frequently develops following obstetric injury. Patients with suspected RVF require thorough evaluation, including history and physical examination, imaging, and objective evaluation of the anal sphincter complex. Prior to attempting repair, sepsis must be controlled and the tract allowed to mature over a period of 3 to 6 months. All repair techniques involve reestablishing a healthy, well-vascularized rectovaginal septum, either through reconstruction with local tissue or tissue transfer via a pedicled flap. The selection of a specific repair technique is determined by the level of the fistula tract and the status of the anal sphincter. Despite best efforts, recurrence is common and should be discussed with patients prior to repair. As the ultimate goal of RVF repair is to minimize symptoms and maximize quality of life, patients should help to direct their own care based on the risks and benefits of available treatment options.

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.

Recto-vaginal fistulas: A case series

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Falandry and Martius’ techniques were used firstly for vesico-vaginal fistulas with satisfying long-term functional results.

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The same techniques are feasible and safe for rectovaginal fistula repair.

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In this case series, patients had an improvement of their self-image and health-related quality of life.

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Temporary colostomy is recommended before this reconstructive surgery.

Introduction

Rectovaginal fistula (RVF) is defined as an abnormal communication between the anterior wall of the rectum and the posterior wall of the vagina. Many surgical techniques have been described in the treatment of RVF. However, none has proved its superiority. The aim of the study was to evaluate the functional results of surgical treatment of RVF using Martius and Falandry techniques in order to assess the feasibility and the efficacy of these techniques which were first described for vesico-vaginal fistulas.

Methods

The study was a retrospective case series conducted in a single centre: Department of general surgery at Ibn Sina University Hospital in Rabat. We included patients with rectovaginal fistula consecutively recruited from 2011 to 2014. 10 patients developed RVF after surgery for rectal cancer (9 cases), uterine cancer (1 case). One patient had RVF for ano-rectal malformation. Colostomy was performed before the treatment of fistula in 9 cases (82 %). They underwent surgical treatment using Falandry (8 patients) and Martius techniques (3 patients) performed by an experienced urologist surgeon.

Results

No postoperative complications were recorded. Time to discharge was postoperative day 3–4. There was a complete disappearance of RVF in 8 patients (72.7 % of cases), relapse in 2 cases (18 %), and failure in one case (9%). The average follow-up was 12.6 +/-10 months. Functionally, no long-term cases of fecal incontinence or dyspareunia were noted.

Conclusion

The choice of surgical technique in the treatment of RVF remains difficult because of poor literature data and absence of consensus. RVF repair results either by Martius or Falandry techniques are encouraging with low morbidity.

Elucidating vaginal fistulas on CT and MRI

Vaginal fistulas (VF) represent abnormal communications between the vagina and either the distal portion of the digestive system or the lower urinary tract, but lack an accepted classification and standardised terminology. Regardless of the underlying cause, these uncommon disorders result in profound physical, psychological, sexual and social distress to the patients.Since diagnosis of VF is challenging at gynaecologic examination, ano-proctoscopy and urethro-cystoscopy, imaging is crucial to confirm the fistula, to visualise its site, course and involved organ, and to characterise the underlying disease. The traditional conventional radiographic studies provided limited cross-sectional information and are nowadays largely replaced by CT and MRI studies.Aiming to provide radiologists with an increased familiarity with VF, this pictorial paper summarises their clinical features, pathogenesis and therapeutic approach, and presents the appropriate CT and MRI acquisition and interpretation techniques that vary according to the anatomic site and termination of the fistula. The current role of state-of-the art CT and MRI is presented with examples regarding both entero- (involving the colon, rectum and anus) and urinary (connecting the bladder, distal ureter or urethra) VF. The resulting combined anatomic and functional cross-sectional information is crucial to allow a correct therapeutic choice and surgical planning.

Minimally invasive treatment of mid-low rectovaginal fistula: a transanal endoscopic surgery study

BACKGROUND

Treatment of rectovaginal fistulas (RVFs) is extremely difficult. No standard surgical procedure is accepted worldwide. The aim of this article was to evaluate a minimally invasive procedure for the repair of mid-low rectovaginal fistula.

METHODS

This is a retrospective review of 17 patients who underwent minimally invasive surgery for the repair of mid-low rectovaginal fistulas (located in the lower or middle one-third of the vaginal wall) at our center between August 2016 and October 2018. The anal approach was adopted for 12 patients: 6 patients were treated directly by rectal mucosal advancement flap (RMAF) with transanal endoscopic surgery (TES), while the other 6 patients underwent initial TES exploration followed by RMAF procedure under direct vision. The vaginal approach was adopted for 5 patients: 3 patients were treated under TES directly and the other 2 were treated under direct vision after initial TES exploration. A total of 9 (52.94%) patients received diverting ileostomy-5 anal approach patients and 4 vaginal approach patients.

RESULTS

Median age of the patients was 46 years (range 10-76 years), and median BMI was 21.9 (range 17.9-28.1). Median operative time was 75 min (range 60-120 min), and median duration of postoperative hospital stay was 8 days (range 6-15 days). Recurrence was seen in 3/12 anal approach patients vs. 0/5 vaginal approach patients. Both the median preoperative and the median postoperative Wexner score were 0 (range 0-2). The median follow-up time was 8 months (range 2-24). No severe complications occurred in any patient.

CONCLUSION

The TES procedure for the treatment of mid-low rectovaginal fistulas avoids any incision of the abdomen and perineal area and appears to be a safe and feasible procedure. This minimally invasive technique is still evolving and is likely to gain wide acceptance in the near future.

Perianal sepsis: surgical perspective and practical MRI reporting for radiologists

This article describes the development of a structured MRI reporting template and diagrammatic worksheet for perianal sepsis through collaboration between radiologists and colorectal surgeons at our institution, and the rationale behind each component of the worksheet. Benefits of this reporting worksheet include optimizing communication of key imaging findings that have a real impact on patient management, less time spent on reporting the study, and easier comparison between studies. We illustrate the utility of the report template with case studies. We summarize the current surgical approaches to perianal sepsis to help radiologists focus on reporting the findings relevant to surgical planning.