Preoperative MR imaging of anal fistulas: Does it really help the surgeon?

Endoscopic therapy in inflammatory bowel diseases (with videos)

Endoscopic therapies are important modalities in the treatment of IBD, adjunct to medical and surgical approaches. These therapeutic techniques are particularly useful in the management of IBD-associated or IBD surgery–associated strictures, fistulas, and sinuses and colitis-associated neoplasia. Although the main focus of endoscopic therapies in IBD has been on balloon stricture dilation and ablation of adenoma-like lesions, new endoscopic approaches are emerging, including needle-knife stricturotomy, needle-knife sinusotomy, endoscopic stent placement, and fistula tract injection. Risk management of endoscopy-associated adverse events is also evolving. The application of endoscopic techniques in novel ways in the treatment of IBD is just beginning and will likely expand rapidly in the near future.

Preoperative mapping of fistula-in-ano: a new three-dimensional MRI-based modelling technique

AIM

We aimed to develop an intuitive, interactive, three-dimensional (3D) MRI modelling technique to produce a 3D image of fistula-in-ano.

METHOD

The 3D model was created from standard two-dimensional (2D) MRI sequences to produce an image that is anatomically correct. Individual muscle and soft-tissue layers were extracted from T1-weighted sequences and fistula pathology from short TI inversion recovery (STIR) sequences, to produce two separate volumes. These were then fused using postprocessing software (Vitrea Workstation version 6.3) to generate a 3D model.

RESULTS

The final 3D model was incorporated into a PDF file that has an integrated computer aided design (CAD) viewer, allowing the surgeon to rotate it in any direction during preoperative planning or whilst in theatre.

CONCLUSION

As an adjunct to 2D MRI images and the associated radiology report, this model communicates the fistula anatomy to the clinician more clearly and should be particularly useful in complex cases.

Imaging techniques and combined medical and surgical treatment of perianal Crohn's disease

Crohn's disease is a chronic inflammatory disease which may involve any segment of the gastrointestinal tract, most frequently the terminal ileum, the large intestine, and the perianal region. The symptoms of perianal Crohn's disease include skin disorders, hemorrhoids, anal ulcers, anorectal stenosis, perianal abscesses and fistulas, rectovaginal fistulas and carcinoma of the perianal region. The perianal manifestations of Crohn's disease cause great discomfort to the patient and are among the most difficult aspects to treat. Management of perianal disease requires a combination of different imaging modalities and a close cooperation between gastroenterologists and dedicated surgeons.

Magnetic resonance enterography in Crohn's disease: a guide to common imaging manifestations for the IBD physician

Patients with Crohn's disease (CD) frequently require cross-sectional imaging. Magnetic resonance enterography (MRE) is an accurate tool for assessment of bowel disease and of various complications of CD. The lack of non-ionizing radiation exposure is an important advantage of this imaging modality. Familiarity with common and pathognomonic imaging features of CD is essential for every clinician that is involved in inflammatory bowel disease (IBD) patients' care. This review is aimed to describe the indications for performing MRE in CD, essentials of MRE techniques and typical radiological findings in patients with CD to aid the IBD doctor in daily practice.

CT imaging with fistulography for perianal fistula: does it really help the surgeon?

OBJECTIVE

To prospectively evaluate the relative accuracy of computed tomography (CT) fistulography for preoperative assessment of fistula in ano.

MATERIALS AND METHODS

Ethical committee approval and informed consent were obtained. A total of 22 patients (15 male and 7 female, age 21-58 years) who were suspected of having fistula in ano underwent preoperative CT fistulography (CTF). The CT images of 0.6 mm were obtained respectively before and after fistulography; contrast-enhanced CT scan was also performed in 22 patients. CTF images were evaluated by two expert radiologists to assess the fistulas in the following respects: (a) the volume-rendered imaging; (b) the extensions of active inflammatory tissue; (c) the internal opening and external opening; (d) the hidden areas of tract or abscess; and (e) the deep abscess adjacent to fistula. CT findings in 18 patients were compared with surgical findings or exam under anesthesia.

RESULTS

The CTF findings in 18 cases were basically in accordance with the surgical findings and/or examination findings under anesthesia. Both coronal and transverse planes were useful in assessing the location and direction of tracts or abscesses. Complicated spatial information within the perianal soft tissue about the fistula with secondary ramifications or abscesses can be easily demonstrated to the surgeons. Contrast-enhanced images were useful in assessing the inflammatory lesion activity and infiltrated area.

CONCLUSION

CTF exquisitely depicts the perianal anatomy and shows the fistulous tracks with their associated ramifications, enables selection of the most appropriate surgical treatment, and therefore minimizes all chances of recurrence.

Imaging techniques for assessment of inflammatory bowel disease: joint ECCO and ESGAR evidence-based consensus guidelines

The management of patients with IBD requires evaluation with objective tools, both at the time of diagnosis and throughout the course of the disease, to determine the location, extension, activity and severity of inflammatory lesions, as well as, the potential existence of complications. Whereas endoscopy is a well-established and uniformly performed diagnostic examination, the implementation of radiologic techniques for assessment of IBD is still heterogeneous; variations in technical aspects and the degrees of experience and preferences exist across countries in Europe. ECCO and ESGAR scientific societies jointly elaborated a consensus to establish standards for imaging in IBD using magnetic resonance imaging, computed tomography, ultrasonography, and including also other radiologic procedures such as conventional radiology or nuclear medicine examinations for different clinical situations that include general principles, upper GI tract, colon and rectum, perineum, liver and biliary tract, emergency situation, and the postoperative setting. The statements and general recommendations of this consensus are based on the highest level of evidence available, but significant gaps remain in certain areas such as the comparison of diagnostic accuracy between different techniques, the value for therapeutic monitoring, and the prognostic implications of particular findings.

Surgical treatment of anorectal crohn disease

Crohn disease involves the perineum and rectum in approximately one-third of patients. Symptoms can range from mild, including skin tags and hemorrhoids, to unremitting and severe, requiring a proctectomy in a small, but significant, portion. Fistula-in-ano and perineal sepsis are the most frequent manifestation seen on presentation. Careful diagnosis, including magnetic resonance imaging or endorectal ultrasound with examination under anesthesia and aggressive medical management, usually with a tumor necrosis factor-alpha, is critical to success. Several options for definitive surgical repair are discussed, including fistulotomy, fibrin glue, anal fistula plug, endorectal advancement flap, and ligation of intersphincteric fistula tract procedure. All suffer from decreased efficacy in patients with Crohn disease. In the presence of active proctitis or perineal disease, no surgical therapy other than drainage of abscesses and loose seton placement is recommended, as iatrogenic injury and poor wound healing are common in that scenario.

A pictorial review of the impact of adding diffusion-weighted MR imaging to other MR sequences for assessment of anal fistulae

The purpose of this article was to review the utility of diffusion-weighted MR imaging (DWI) findings in anal fistulae compared to other sequences, and to become familiar with the wide variety of DWI findings of this entity. DWI is useful for evaluating anal fistulae because it makes it possible to detect small lesions and many lesions at the same time, show the spread of the lesions, and assess the degree of inflammation, and it can be useful when following up anal fistulae.

[3.0T MRI with a high resolution protocol for the study of benign disease of the anus and rectum. Part 2: Anorectal inflammatory disease. Postsurgical anatomy and complications after treatment]

Benign anorectal disease comprises a broad group of processes with very diverse origins; these processes may be congenital or acquired as well as inflammatory or tumor related. However, benign anorectal disease has received less attention in the scientific literature than malignant disease. In this second part of this image-based review of benign anorectal disease, we describe the most common inflammatory and fistulous diseases, the postsurgical anatomy, and complications that can occur after surgical treatment or radiotherapy for anorectal disease.

The evaluation and treatment of Crohn perianal fistulae: EUA, EUS, MRI, and other imaging modalities

Perianal fistulizing disease is a common complication of CD that requires a multidisciplinary collaboration between gastroenterology, surgery, and radiology professionals for successful assessment and treatment. Optimal success comes from a combined medical and surgical approach to treat the fistulizing disease (see Fig. 1). Unfortunately, even with a variety of surgical options, a subset of patients require permanent fecal diversion and/or proctectomy to successfully treat their disease. Further studies (likely requiring large, multicenter trials) of novel medical and surgical treatments are still warranted to formulate optimal management of this complex condition.

MR imaging evaluation of perianal fistulas: spectrum of imaging features

Perianal fistulization is an inflammatory condition that affects the region around the anal canal, causing significant morbidity and often requiring repeated surgical treatments due to its high tendency to recur. To adopt the best surgical strategy and avoid recurrences, it is necessary to obtain precise radiologic information about the location of the fistulous track and the affected pelvic structures. Until recently, imaging techniques played a limited role in evaluation of perianal fistulas. However, magnetic resonance (MR) imaging now provides more precise information on the anatomy of the anal canal, the anal sphincter complex, and the relationships of the fistula to the pelvic floor structures and the plane of the levator ani muscle. MR imaging allows precise definition of the fistulous track and identification of secondary fistulas or abscesses. It provides accurate information for appropriate surgical treatment, decreasing the incidence of recurrence and allowing side effects such as fecal incontinence to be avoided. Radiologists should be familiar with the anatomic and pathologic findings of perianal fistulas and classify them using the St James's University Hospital MR imaging-based grading system.

Managing Perianal Crohn’s Disease

Perianal Crohn’s Disease (CD) is a significant cause of morbidity in CD patients. Accurate identification of perianal involvement requires advanced imaging techniques in addition to physical exam. Treatment of the disease is aimed at improving both the perianal and intestinal manifestations. Proper treatment depends upon the severity of the disease and combines current medical and surgical therapies to maximize response. The ability to improve perianal disease has grown significantly since the introduction of anti-TNF agents which are now a mainstay of treatment along with antibiotics and immunomodulators. New experimental therapies are limited by lack of research to support their use.

Magnetic resonance fistulogram demonstration of urethrovesicovaginal fistula in a case of müllerian agenesis due to traumatic urethral coitus

Vesicovaginal fistula is not uncommon in women of childbearing age, and can occur due to a multitude of causes, the chief ones being infection and neoplasia. An extensive PUBMED search yielded only a few reports describing causation of such a lesion due to traumatic urethral coitus. The classic method to demonstrate such fistulas is by direct contrast-enhanced fistulography. Herein we report a case of urethrovesicovaginal fistula with müllerian agenesis caused by traumatic urethral coitus, as demonstrated using indirect magnetic resonance fistulography.

MRI in evaluation of perianal fistula

This essay illustrates the usefulness of MRI in evaluating perianal fistulas, a common disease, notorious for recurrence if not assessed and treated adequately. MRI exquisitely depicts the perianal anatomy and shows the fistulous tracks and their associated ramifications and abscesses. It thus provides an excellent preoperative understanding of the disease, enabling selection of the most appropriate surgical treatment and therefore minimising all chances of recurrence.

MRI in Crohn's disease--current and future clinical applications

Crohn's disease is a chronic, disabling disease that, over time, can lead to irreversible bowel damage. MRI can be used to diagnose and assess the activity, severity and complications of Crohn's disease; however, the role of MRI in therapeutic monitoring of changes in disease-related intestinal damage is still to be defined. Objective, validated MRI-based scores have been developed to assess the activity of Crohn's disease; these indices are based on the extent and severity of intestinal inflammation, postoperative recurrence and perianal disease. MRI is accurate, safe, reproducible and can allow repeated evaluations of patients without radiation exposure. Evidence that MRI might be valuable in the therapeutic monitoring of patients with Crohn's disease is increasing and, in combination with endoscopy and surgical history, this imaging technique could enable clinicians to assess Crohn's-disease-related intestinal damage. MRI could, therefore, have a crucial role in a future 'damage-driven' treatment paradigm--in which imaging is used to monitor intestinal damage and medication use is targeted to prevent the accumulation of further damage. This damage-driven therapeutic approach could potentially change the course of Crohn's disease.

MRI in Crohn's disease--current and future clinical applications

Crohn's disease is a chronic, disabling disease that, over time, can lead to irreversible bowel damage. MRI can be used to diagnose and assess the activity, severity and complications of Crohn's disease; however, the role of MRI in therapeutic monitoring of changes in disease-related intestinal damage is still to be defined. Objective, validated MRI-based scores have been developed to assess the activity of Crohn's disease; these indices are based on the extent and severity of intestinal inflammation, postoperative recurrence and perianal disease. MRI is accurate, safe, reproducible and can allow repeated evaluations of patients without radiation exposure. Evidence that MRI might be valuable in the therapeutic monitoring of patients with Crohn's disease is increasing and, in combination with endoscopy and surgical history, this imaging technique could enable clinicians to assess Crohn's-disease-related intestinal damage. MRI could, therefore, have a crucial role in a future 'damage-driven' treatment paradigm--in which imaging is used to monitor intestinal damage and medication use is targeted to prevent the accumulation of further damage. This damage-driven therapeutic approach could potentially change the course of Crohn's disease.

Gastroenterology review and perspective: the role of cross-sectional imaging in evaluating bowel damage in Crohn disease

OBJECTIVE

This article will review the performance and limitations of cross-sectional imaging methods to detect and display critical features of Crohn disease (CD)-related bowel damage, including stenosis and penetrating complications (i.e., fistula, abscess). International efforts to incorporate cross-sectional imaging findings along with endoscopic and surgical findings to create a global bowel damage score over the length of the gastrointestinal tract are summarized along with the rationale for these efforts.

CONCLUSION

The first digestive damage score, the Lémann score, will incorporate surgical history, endoscopic findings, and imaging findings of stenosis and penetrating complications to provide a global assessment of CD-related destruction of the gastrointestinal tract. It is anticipated that the score will permit better understanding of the impact of modern therapeutics on the natural history of CD. Because CT is a technique that involves ionizing radiation and accuracy of ultrasound is highly related to CD location, MRI is proposed as first choice for nonemergent follow-up of CD patients.

Diffusion-weighted MRI for evaluating perianal fistula activity: feasibility study

PURPOSE

To assess the feasibility of using diffusion-weighted magnetic resonance (MR) imaging (DWI) for evaluating perianal fistula activity.

MATERIALS AND METHODS

This study retrospectively assessed 24 patients with clinically suspected perianal fistula who underwent a total of 28 MR examinations after conservative treatment with antibiotics. DWI was performed at 1.5 T, using b-values of 0 and 1000 s/mm(2). Apparent diffusion coefficient (ADC) maps were created and ADCs of the lesions were measured. Lesions were classified into two groups based on the need for surgery and surgical findings: positive inflammation activity (PIA) and negative inflammation activity (NIA). ADCs of both groups were compared using an unpaired t-test, and Receiver Operating Characteristic (ROC) analysis was performed.

RESULTS

The ADC (in 10(-3) mm(2)/s) of the PIA group (0.908±0.171) was significantly lower (P=0.0019) than that of the NIA group (1.124±0.244). The area under the ROC curve was 0.749. An optimal cut-off ADC of 1.109 yielded a sensitivity of 95.7%, a specificity of 50%, a positive predictive value of 71%, and a negative predictive value of 90%.

CONCLUSION

DWI is a feasible method for evaluating perianal fistula activity. The diagnostic performance of this technique should be established in future, larger prospective studies.

MRI in perianal fistulae

MRI has become the method of choice for evaluating perianal fistulae due to its ability to display the anatomy of the sphincter muscles orthogonally, with good contrast resolution. In this article we give an outline of the classification of perianal fistulae and present a pictorial assay of sphincter anatomy and the MRI findings in perianal fistulae. This study is based on a retrospective analysis of 43 patients with a clinical diagnosis of perianal fistula. MRI revealed a total of 44 fistulae in 35 patients; eight patients had only perianal sinuses.

New concepts in intestinal imaging for inflammatory bowel diseases

In the last decade, multiple imaging technologies have been developed that improve visualization of the mucosal, mural, and perienteric inflammation associated with inflammatory bowel diseases. Whereas these technologies have traditionally been used to detect and stage suspected enteric inflammation, we review new, emerging roles in detecting clinically occult inflammation (in asymptomatic patients) and inflammatory complications, predicting response prior to therapy, assessing response after therapy, and enteric healing. We compare the relative performance of these technologies in detecting inflammation, focusing on their advantages and disadvantages and how they might complement each other. We also discuss their potential benefits for patients and clinical trials, reviewing technologic developments and areas of research that could provide important insights into the pathophysiology of inflammatory bowel diseases-related enteric inflammation.

Three-dimensional endoanal ultrasonography in daily proctological practice

Three-dimensional endoanal ultrasonography (3D-EAUS) provides unequalled quality in terms of the anatomical image of the anal canal and sphincter complex. In less than one minute it produces a three-dimensional "cube" that can be manipulated in all spatial dimensions, then archived. In just a few years it has become a new gold standard exploration in proctology. In addition to image quality, 3D-EAUS has the advantage of being easily and rapidly performed, well-tolerated and moderate in cost. For anal incontinence, 3D-EAUS contributes to the identification of sphincter defects. The anatomy of the sphincters can be evaluated spatially. Simple scoring systems with good reproducibility and readily applicable in routine practice can be used to evaluate the "damaged" sphincter volume. For the management of anoperineal suppurations, 3D-EAUS provides information on the fistulous track(s) and on potential collections. These data are crucial as the choice of treatment and its efficacy depend on accurate topographic assessment of the suppuration and the state of the sphincter apparatus.

Role of magnetic resonance imaging in evaluation of the activity of perianal Crohn's disease

AIM

To evaluate the diagnostic ability of contrast-enhanced Magnetic Resonance Imaging (MRI) in assessment of the activity of perianal fistulas in Crohn's disease (CD) patients, compared to clinical data.

MATERIALS AND METHODS

Fifty CD patients (25 men; mean[SD] age: 40.4[12.6] years) with known or suspected perianal fistulas underwent perianal space MRI. Radiological activity of disease was measured as the percentage increase (PI) of ROI values of fistulas in relation to ROI values of healthy local fat, after contrast administration. Clinical activity of disease was defined according to Perianal Disease Activity Index (PDAI) and Fistula Drainage Assessment (FDA).

RESULTS

Forty-two patients presented perianal disease at MRI (55 fistulas identified). An association between both fistula's PI and PDAI (Pearson's coefficient 0.512, p<0.0001) and between PI and FDA (p=0.003) was demonstrated. Areas under ROC curves of PI values in relation to PDAI and FDA were respectively 0.876 [95%CI=(0.743-1.00), p<0.001] and 0.784 [95%CI=(0.588-0.980), p=0.003]. A cut-off value of PI, calculated on these preliminary data, correctly classified more than 90% of fistulas.

CONCLUSIONS

Contrast-enhanced MRI with PI calculation offered practical information about activity of perianal fistulas and might be helpful in providing a comprehensive evaluation of CD perianal disease.

Anorectal Crohn's disease

Crohn's disease manifests with perianal or rectal symptoms in approximately one-third of patients, and is associated with a more aggressive natural history. Due to the chronic relapsing nature of the disease, surgery has been traditionally avoided. However, combined medical and surgical intervention when treating perianal fistulae has been shown to offer the best chance for success. Endoanal ultrasound examination or pelvic magnetic resonance imaging should be done in conjunction with an examination under anesthesia to characterize the disease. Any abscess should be drained and setons placed if there is active rectal inflammation or complex fistulae. Antibiotics and immunosuppressive therapy (especially with infliximab) should also be initiated. Simple fistulae can be treated surgically by fistulotomy or anal fistula plug. Complex fistulae can be closed with either an anal fistula plug or covered with flaps. Up to 20% of patients anorectal Crohn's disease require proctectomy for persistent and disabling disease.

Novel diagnostic and prognostic modalities in inflammatory bowel disease

Inflammatory bowel disease remains a complex disease with variable clinical presentations and often nonspecific symptoms. Physicians must rely on diagnostic tools for clarification of disease diagnosis and for guiding management of patients with established disease. Advances in radiologic imaging modalities facilitate early and accurate detection of luminal disease and extraluminal complications. The introduction and dissemination of small bowel capsule endoscopy and double-balloon enteroscopy permit detailed visualization and sampling of the mucosa throughout the entire bowel. Serologic biomarkers are evolving as a valuable tool to clarify diagnosis and stratify patients by disease phenotypes and patterns of behavior. Neutrophil-derived fecal biomarkers are emerging as useful surrogate markers of intestinal inflammation with the potential for a variety of clinical applications, but their application to clinical management has not yet been clarified.

Novel diagnostic and prognostic modalities in inflammatory bowel disease

Inflammatory bowel disease remains a complex disease with variable clinical presentations and often nonspecific symptoms. Physicians must rely on diagnostic tools for clarification of disease diagnosis and for guiding management of patients with established disease. Advances in radiologic imaging modalities facilitate early and accurate detection of luminal disease and extraluminal complications. The introduction and dissemination of small bowel capsule endoscopy and double-balloon enteroscopy permit detailed visualization and sampling of the mucosa throughout the entire bowel. Serologic biomarkers are evolving as a valuable tool to clarify diagnosis and stratify patients by disease phenotypes and patterns of behavior. Neutrophil-derived fecal biomarkers are emerging as useful surrogate markers of intestinal inflammation with the potential for a variety of clinical applications, but their application to clinical management has not yet been clarified.

Editorial: Imaging and the treatment of Crohn's perianal fistulas: to see is to believe

Fistulizing Crohn's disease is associated with significant morbidity. Although treatment has improved over the last decade, there is still considerable room for improvement. One possible method to improve outcomes is to use advanced imaging techniques, such as endoscopic ultrasound (EUS) or magnetic resonance imaging (MRI), to help guide treatment. In this issue, Ng et al. show again the disconnect between cessation of drainage and the actual deep healing that can be appreciated using these imaging techniques. The authors used MRI to help guide the decision on when to alter medical therapy and were able to identify a subset of patients who could discontinue infliximab. Other authors over the last 5-10 years have also shown the benefit of EUS and MRI in these patients. The time has come for us to not only embrace these imaging modalities as valid end points for clinical trials but more importantly as a means to improve outcomes for our patients with fistulizing Crohn's disease.

Imaging of perianal fistulas

Perianal fistulas, cryptoglandular or Crohn's disease-related, have a tendency to recur. Recurrence usually is owing to missed infection during surgery for cryptoglandular fistulas or insufficient response to medical treatment in Crohn's disease. It is now recognized that preoperative imaging (endoanal ultrasound and magnetic resonance imaging) can help to identify extensions that otherwise would be missed during surgery and therefore prevent recurrence. For medical therapy, the extent of the disease and the presence of abscesses are identified with imaging and therapy response can be monitored. The purpose of this review is to give an up-to-date overview of the anal anatomy, classification of perianal fistulas, and the role of imaging modalities in the management of patients with perianal fistulas.

Emerging treatments for complex perianal fistula in Crohn’s disease

Complex perianal fistulas have a negative impact on the quality of life of sufferers and should be treated. Correct diagnosis, characterization and classification of the fistulas are essential to optimize treatment. Nevertheless, in the case of patients whose fistulas are associated with Crohn’s disease, complete closure is particularly difficult to achieve. Systemic medical treatments (antibiotics, thiopurines and other immunomodulatory agents, and, more recently, anti-tumor necrosis factor-α agents such as infliximab) have been tried with varying degrees of success. Combined medical (including infliximab) and less aggressive surgical therapy (drainage and seton placement) offer the best outcomes in complex Crohn’s fistulas while more aggressive surgical procedures such as fistulotomy or fistulectomy may increase the risk of incontinence. This review will focus on emerging novel treatments for perianal disease in Crohn’s patients. These include locally applied infliximab or tacrolimus, fistula plugs, instillation of fibrin glue and the use of adult expanded adipose-derived stem cell injection. More well-designed controlled studies are required to confirm the effectiveness of these emerging treatments.

What every gastroenterologist needs to know about common anorectal disorders

Anorectal complaints are very common and are caused by a variety of mostly benign anorectal disorders. Many anorectal conditions may be successfully treated by primary care physicians in the outpatient setting, but patients tend not to seek medical attention due to embarrassment or fear of cancer. As a result, patients frequently present with advanced disease after experiencing significant decreases in quality of life. A number of patients with anorectal complaints are referred to gastroenterologists. However, gastroenterologists’ knowledge and experience in approaching these conditions may not be sufficient. This article can serve as a guide to gastroenterologists to recognize, evaluate, and manage medically or non-surgically common benign anorectal disorders, and to identify when surgical referrals are most prudent. A review of the current literature is performed to evaluate comprehensive clinical pearls and management guidelines for each topic. Topics reviewed include hemorrhoids, anal fissures, anorectal fistulas and abscesses, and pruritus ani.

[Progress in diagnostics of anorectal disorders. Part II: radiology]

Diagnostics and therapy of anorectal disorders remain a surgical question. In close cooperation between different departments (radiology and gastroenterology, urology and gynecology, dermatology and psychology), the role of radiologic imaging is of growing importance. Exact knowledge of functional anatomy and precise clinical examination constitute the basis of the according therapeutic strategies. In this context radiology has contributed decisively. Developments in imaging techniques, e.g. dynamic MRI, highly contributed to better understanding of complex functional pelvic floor disorders. The combination of nanotechnology and high-resolution imaging allows precise staging, especially in rectal cancer. Furthermore, advances in virtual colonoscopy could lead to widely acceptable and patient-friendly screening for colorectal malignancies.

Optimal methods for staging rectal cancer

At present, several modalities exist for the preoperative staging of rectal lesions, including computed tomography (CT), body coil or endorectal coil magnetic resonance imaging (MRI), endoscopic ultrasonography (EUS) done by rigid or flexible probes, and positron emission tomography (PET). Staging accuracy for CT ranges from 53% to 94% for T-stage accuracy and from 54% to 70% for N-stage accuracy. Improved CT accuracy is observed at higher disease stages. Body coil MRI has shown T- and N-stage accuracy ranging from 59% to 95% and 39% to 95%, respectively. Endorectal coil MRI has shown improved T- and N-stage accuracy, with rates of 66% to 91% and 72% to 79%, respectively. The development of phased-array MRI, combining high spatial resolution with a larger field of view, offers promise to improve on these rates. EUS, considered the current gold standard, has shown T-stage accuracy ranging from 75% to 95%, with N-stage accuracy ranging from 65% to 80%. Flexible EUS probes have the advantage of being able to access and sample iliac nodes. Recent studies also suggest that three-dimensional EUS may provide greater accuracy than conventional two-dimensional EUS. Limited studies exist on the use of PET in primary tumor staging. PET may upstage disease in 8% to 24% of patients and has also been used in posttreatment restaging and surveillance. Postradiation edema, necrosis, and fibrosis seem to decrease restaging accuracy in all modalities. This article reviews the current literature about the staging accuracy of the various modalities and suggests a staging algorithm for rectal cancer.

Indications for body MRI Part II: retroperitoneum, intestines and pelvis

In this article an overview is given of the present knowledge of whole body MRI, MRI of the retroperitoneum, intestines and pelvis. Recommendations are based on current literature and clinical applications in daily routine focusing on efficacy rather than cost considerations. The contribution and complementary role of MRI relative to those of its competing modalities was the most important endpoint assessed. Perfusion and functional information, as well as specific contrast agents in the area of the pelvis are still considered research indications.

Diagnostics of inflammatory bowel disease

The diagnosis of inflammatory bowel disease (IBD) with its 2 main subforms, Crohn's disease and ulcerative colitis, is based on clinical, endoscopic, radiologic, and histologic criteria. This paradigm remains unchanged despite the advent of new molecular technologies for the examination of serum proteins and genetic sequences, respectively. The main innovations in diagnostic technologies include the development of more sophisticated endoscopic and noninvasive imaging techniques with the aim of improving the identification of complications, in particular malignant diseases associated with IBD. The future will see further progress in the identification of genetic susceptibility factors and of protein biomarkers and their use to describe the molecular epidemiology of IBD. It can be expected that future diagnostic algorithms will include molecular parameters to detect early disease or guide therapies by predicting the individual course of disease.

Imaging of perianal Crohn's disease

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

Utility of magnetic resonance imaging in anorectal disease

Imaging of both benign and malignant anorectal diseases has traditionally posed a challenge to clinicians, and as a result history and physical exam have been relied on heavily. CT scanning and endorectal ultrasound have become popular in assessment of anatomy and staging of tumors, but have limitations. Magnetic resonance imaging (MRI) has the capability to fill in the gaps left open by more conventional imaging modalities and continues to be promising as the definitive imaging technique in the pelvis, especially with advancement of emerging technologies in this field. A comprehensive review of this topic has been undertaken. Anorectal disease is divided into three broad categories: cancer, fistula/abscess, and pelvic floor disorders. A review of the literature is performed to evaluate the use of MRI and other imaging modalities in these three areas. Preoperative imaging is useful in the evaluation of all three areas of anorectal disease. MRI is an effective tool in delineating anatomy and, when correlating with the specific clinical scenario, is an effective adjunct in clinical decision-making in order to optimize outcome. MRI continues to be a promising and novel approach to imaging various afflictions of the anorectum and the pelvic floor. Its role is more well-established in some areas than in others, and there are still significant limitations. As technology advances, MRI will shed more light on a complex anatomical area.

Infliximab in the treatment of Crohn's disease

The recent introduction of infliximab, a chimeric monoclonal antibody against tumor necrosis factor-alpha, has greatly modified the treatment of Crohn's disease (CD). Data from the literature show encouraging results after intravenous infusion both for closure of intestinal or perianal fistulas and for induction and maintenance of remission in patients with moderate to severe intestinal disease unresponsive to other treatments. However, some contraindications such as fibrostenosing CD and sepsis have been identified. In addition, the data on long-term outcomes and safety is still limited. Our initial experience showed that in selected cases local injection of infliximab is effective in the treatment of complex perianal disease offering the possibility of using such treatment even in small bowel obstructing disease with minimal systemic effects. This paper analyzes the state of the use of both intravenous and local injection of infliximab in patients with CD.

The patient with persistent perianal fistulae

The management of patients with persistent perianal fistulae depends on thorough evaluation by clinical history and examination, assessment of intestinal disease and assessment of perianal disease. The main therapeutic options are medical and surgical treatment and their appropriate integration is essential for the optimal management of the patients. Medical treatment includes antibiotics, azathioprine or 6-mercaptopurine, infliximab and tacrolimus or cyclosporine. Surgical treatment includes fistulotomy, placement of setons, endorectal advancement flaps, fecal diversion and proctectomy. Fistula recurrence often occurs, possibly due to early discontinuation of medication or premature removal of setons. Using anorectal endoscopic ultrasound or magnetic resonance imaging to guide therapy, the healing rates of perianal fistula can be increased. In persistent complex perianal fistulae where medical treatment initially fails, examination under anaesthesia and placement of non-cutting setons, when necessary, combined with medical treatment results in higher healing rates.

Magnetic resonance imaging of the ischiorectal fossa: spectrum of disease

OBJECTIVE

Pelvic magnetic resonance imaging (MRI) studies are widely used to assess the rectum, anal canal, and their environment. The purpose of this article is to review the current role of MRI in the evaluation of diseases involving the ischiorectal fossa and their imaging features.

CONCLUSIONS

The radiologist plays an essential role in the evaluation of some conditions typically located in this space and of other conditions that occasionally involve this area or invade the ischioanal space. The accurate assessment of these diseases that MRI provides further cements its role as the primary technique for the evaluation of pelvic pathology.

Perianal fistulas in Crohn's disease: MRI diagnosis and surgical planning: MRI in fistulazing perianal Crohn's disease

Crohn's disease is a chronic, transmural inflammatory process of the gastrointestinal tract. It often affects the colon with the perianal area. The most common intestinal manifestations include external and/or internal fistulas and abscesses. Assessment of the activity of perianal fistulas in the course of Crohn's disease seems to be an important factor influencing therapeutic approach. Fistula's activity is evaluated by such methods as magnetic resonance imaging, anal ultrasound and examination under anaesthesia. Usefulness of imaging methods in the diagnosis of fistulas still remains to be defined.MRI is used to present a wide spectrum of perianal fistulazing Crohn's disease. Additionally, it is an important instrument revealing location, extent and severity of inflammation. It is also very helpful to detect clinically silent sepsis related to small, local inflammation. The most common method used in MR imaging to assess topography of a fistula's track, is Parks' classification.Clinical indications to MRI may include follow-up studies of a diagnosed disease, classification of fistulas' subtypes in the course of Crohn's disease, determination of the extent of fistulas' tracts and spread of an inflammatory process what can guide surgical procedures.

Long-term outcome following mucosal advancement flap for high perianal fistulas and fistulotomy for low perianal fistulas: recurrent perianal fistulas: failure of treatment or recurrent patient disease?

BACKGROUND

In this study, we determined the long-term outcome of perianal fistulas treated with mucosal advancement flap (MF) or fistulotomy (FT).

METHODS

One hundred three patients with perianal fistulas were treated by MF for high fistulas or FT for low fistulas and were retrospectively assessed by case-note review and examined at the out-patient clinic. The localization and time of recurrence of the fistula were recorded.

RESULTS

Forty-one patients [median follow-up of 72 months (range 48-99)] were treated by an MF, and 62 patients [median follow up of 75 months (range 48-99)] were treated by FT. After 12, 48, and 72 months, the fistula had recurred in 9 (22%), 26 (63%), and 26 (63%) patients of the MF group and in 4 (7%), 16 (26%), and 24 (39%) patients of the FT group, respectively. Eighteen (69%) of the recurrences in the MF group and ten (33%) of the FT group occurred within 24 months after surgery (p=0.01). Four (15%) of the recurrences in the MF group and 13 (54%) of the recurrences in the FT group were present in a different localization (p=0.007).

CONCLUSION

The success rate of both FT and MF techniques decreases with time. Recurrence appears to be caused by failure of treatment and by recurrent patient disease.

Infliximab in fistulizing Crohn's disease

The treatment of fistulizing CD has evolved greatly in the last 15 years, largely caused by improvements in medical therapy. Tables 2 and 3 summarize all published controlled and uncontrolled trials of immunomodulator and biologic therapy for the treatment of Crohn's fistulae. The advent of immunomodulators and anti-TNF-alpha agents has transformed the treatment of Crohn's fistulae from almost exclusively surgical to placing a much larger emphasis on medical therapy, either as initial therapy alone, with surgery reserved for refractory cases, or in combination with surgery from the start. For this reason, surgeons and gastroenterologists must work in concert to provide the best care for each patient. Proper fistula management also relies heavily on accurate diagnosis, especially defining the anatomy of the fistula, ascertaining whether abscess formation is present, and determining the location and extent of intestinal inflammation.