Perianal fistulas in Crohn’s disease: MRI diagnosis and surgical planning

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.     

MRI features of perianal fistulas: is there a difference between Crohn’s and non-Crohn’s patients?

Purpose

Though perianal fistulas are commonly seen in patients with Crohn’s disease, they can also be seen in patients without inflammatory bowel disease. The purpose of this study was to evaluate MR imaging differences of perianal fistulas in patients with and without Crohn’s disease.

Methods

Our retrospective search from January 2012 to December 2015 of the Radiology database for perianal fistula yielded 207 patients. Only patients with dedicated MR fistula protocol studies were included, whereas patients with previous anal surgery or anastomosis, anorectal tumors, and equivocal findings that could not be definitely assessed as a fistula were excluded. The following features were assessed: anatomic type of fistula (Parks Classification), luminal origin (hour clock position), anal verge distance, signs of acute inflammation, circumference of anus involved by inflammation, presence of rectal inflammation. and abscess.

Results

One hundred and twenty six of 207 patients met inclusion criteria. Of these, 96 (76.2%) had Crohn’s disease and 30 (23.8%) did not. The most common fistulas identified were transphincteric (38.5% of Crohn’s and 50% of non-Crohn’s) and intersphincteric (33.3% of Crohn’s and 35.4% of non-Crohn’s). An abscess was associated in 41 cases, 32 (33.3%) in the Crohn’s group and 9 (30.0%) in the non-Crohn’s group. Rectal inflammation was present in 29 patients with Crohn’s disease (29.2%) and in 2 without Crohn’s (6.7%). This finding was statistically significant (p = 0.0009).

Conclusions

Our study demonstrates that while both groups can have similar MR imaging features, accompanying rectal inflammation was more commonly seen in Crohn’s disease.

     

The comparison of CT fistulography and MR imaging of perianal fistulae with surgical findings: a case–control study

Purpose

The purpose of this study was to evaluate the diagnostic efficacies of CT fistulography and MRI, in the diagnostic work-up of perianal fistula patients.

Materials and methods

All 41 patients who were included in the study (36 males and 5 females, with an average age of 41 years) underwent CT fistulography and MRI examinations prior to surgery. The fistula characteristics obtained from these examinations were compared with the surgical findings. The comparative results were evaluated by means of the Kappa analysis method.

Results

CT fistulography predicted the correct perianal fistula classification in 30 (73.1%) of the 41 patients, whereas MRI correctly defined fistula classification in 38 (92.7%) of these patients (the K values were 0.621 and 0.896, respectively; with p < 0.001). CT fistulography depicted 29 secondary extensions in 16 patients, whereas MR imaging revealed 28 secondary extensions in 15 patients. A substantial agreement was found between surgical findings and two modalities (K value was 0.789 and 0.793 for CT fistulography and MRI, respectively, with a p value < 0.001). In terms of locations of internal openings, CT fistulography was able to detect the locations in 28 patients (68.2%), whereas MRI was more successful in this aspect, with a number of 35 patients (85.3%). Granulation tissues, inflammation and edema around the fistula, abscesses, and fistular wall fibrosis were also evaluated.

Conclusion

CT fistulography and MRI have different advantages in the diagnosis of perianal fistulas. A good command of knowledge concerning the issue may be a key factor in modality decision.

     

MRI characteristics of proctitis in Crohn’s disease on perianal MRI

Purpose

Multiple features have been described for assessing inflammation in Crohn’s disease (CD) in MR enterography, but have not been validated in perianal magnetic resonance imaging (MRI). Retrospectively, we studied which MRI features are valuable in assessing proctitis.

Materials and methods

CD patients (≥18 years) who underwent colonoscopy (reference standard) and perianal fistula MRI within 8 weeks were included. Seventeen MRI features were blindly scored by three observers and correlated to endoscopy (regression analysis). Reproducibility (multirater kappa, intraclass correlation coefficient) was determined for all three observer pairs. MRI features were considered relevant when significantly correlated to endoscopy for ≥2 observers, and reproducibility was ≥0.40 for ≥2 observer pairs.

Results

Perianal MRI of 58 CD patients were included. Wall thickness, rectal mural fat, creeping fat, and size of mesorectal lymph nodes showed a significant correlation with endoscopy for ≥2 observers (p = 0.000–0.023, p = 0.011–0.172, p = 0.007–0.011 and p = 0.000–0.005, respectively) with a kappa/intraclass correlation coefficient of ≥0.60 for ≥2 observer pairs. Perimural T2 signal and perimural enhancement significantly correlated to endoscopy (all p values ≤0.05) for all three observers and the reproducibility was ≥0.40 for ≥2 observer pairs. Mural T2 signal and degree and pattern of T1 enhancement showed significant correlation to endoscopy for two observers, but with poor to moderate reproducibility.

Conclusion

Wall thickness, mural fat, and mesorectal features (perimural T2 signal, perimural enhancement, creeping fat, and size of mesorectal lymph nodes) had significant correlation to endoscopy and were reproducible in diagnosing proctitis. Some established luminal features in MRE were considered not useful.

     

Prostate MRI–TRUS fusion biopsy: a review of the state of the art procedure

Abdominal Radiology - Prostate cancer is the fourth most common cancer and population-based screening programmes are being increasingly adopted worldwide. Screening-positive patients undergo...     

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.     

PET-CT detection of abdominal recurrence of ovarian cancer: radiologic–surgical correlation

The diagnosis of recurrent ovarian cancer can be difficult on cross-sectional imaging, and variable sensitivities and specificities have been reported for positron emission tomography (PET). Combined functional and anatomic imaging with PET plus computed tomography (CT) potentially allows for improved detection of tumor masses. We investigated the sensitivity, specificity, and accuracy of PET-CT for the diagnosis of recurrent ovarian cancer. Sixteen women with previously treated ovarian cancer underwent imaging on a combined PET-CT scanner followed by surgery to assess for possible recurrent disease. The fused PET-CT images were retrospectively reviewed for recurrent disease, and the results of PET-CT were compared with the operative notes. Eleven of the 16 patients had recurrent disease at surgery. The sensitivity, specificity, and accuracy of PET-CT for disease detection on a per-patient basis were 72.7%, 40%, and 62.5%, respectively. For cases of malignant adenopathy (n = 7), 100% were detected on PET-CT. For peritoneal lesions no larger than 1 cm (n = 23), 13% were detected on PET-CT. For peritoneal lesions larger than 1 cm (n = 8), 50% were detected on PET-CT. The sensitivity of PET-CT for recurrent ovarian cancer is moderate in patients with low volume disease. A trial involving a larger number of patients with a spectrum of disease volumes is necessary to determine the impact of PET-CT in clinical practice.     

MRI of the heart: promises fulfilled?

Cardiac magnetic resonance imaging (MRI) has established itself as an important noninvasive method of evaluating a wide array of cardiovascular diseases. Despite these successes, questions remain about whether cardiac MRI is the best way to evaluate patients with complex cardiac conditions in whom more traditional diagnostic techniques have been inconclusive. We review the most important current applications of MRI in heart failure, ischemic heart disease, and myocardial disease.     

Multidetector CT enterography of focal small bowel lesions: a radiological–pathological correlation

Abdominal Radiology - Focal small bowel lesions present a diagnostic challenge for both the radiologist and gastroenterologist. Both the detection and characterization of small bowel masses have...     

Diagnosis of a variant of Mayer–Rokitansky–Kuster–Hauser syndrome: useful MRI findings

Mayer–Rokitansky–Kuster–Hauser (MRKH) syndrome consists of vaginal aplasia associated with other müllerian duct abnormalities. Its penetrance varies, as does the involvement of other organ systems. Type I MRKU syndrome is characterized by an isolated absence of the proximal two thirds of the vagina, whereas type II is marked by other malformations which include vertebral, cardiac, urologic (upper tract), and otologic anomalies. In both types, the extent of vaginal aplasia varies, ranging from virtually absent to a length much more inferior than the normal one (2–5 cm). MRKU syndrome usually remains undetected until the patient presents with primary amenorrhea despite normal female sexual development. It is important to underline the fact that this syndrome is the second most common cause of primary amenorrhea. Although this condition has psychologically devastating consequences, its anatomical defects can be surgically treated. In fact, following diagnosis, surgery allows patients to have normal sexual function while reproduction may be possible if assisted techniques are performed.     

TRUS–MRI image registration: a paradigm shift in the diagnosis of significant prostate cancer

Accuracy of multiparametric MRI has greatly improved the ability of localizing tumor foci of prostate cancer. This property can be used to perform a TRUS–MR image registration, new technological advance, which allows for an overlay of an MRI onto a TRUS image to target a prostate biopsy toward a suspicious area Three types of registration have been developed: cognitive-based, sensor-based, and organ-based registration. Cognitive registration consists of aiming a suspicious area during biopsy with the knowledge of the lesion location identified on multiparametric MRI. Sensor-based registration consists of tracking in real time the TRUS probe with a magnetic device, achieving a global positioning system which overlays in real-time prostate image on both modalities. Its main limitation is that it does not take into account prostate and patient motion during biopsy. Two systems (Artemis and Uronav) have been developed to partially circumvent this drawback. Organ-based registration (Koelis) does not aim to track the TRUS probe, but the prostate itself to compute in a 3D acquisition the TRUS prostate shape, allowing for a registration with the corresponding 3D MRI shape. This system is not limited by prostate/patient motion and allows for a deformation of the organ during registration. Pros and cons of each technique and the rationale for a targeted biopsy only policy are discussed.     

Patients’ awareness of the surgical risks of smoking: Implications for supporting smoking cessation

Objective

To describe the smoking patterns of patients receiving elective surgery and their knowledge about the benefits of smoking cessation to inform and strengthen support for patients to quit smoking in order to optimize surgical outcomes.

Design

Patients who had elective surgery were screened for smoking status, and eligible patients completed a telephone survey.

Setting

Two regional hospitals in northern British Columbia.

Participants

Of 1722 patients screened, 373 reported smoking before surgery. Of these, 161 (59.0% women) completed a telephone survey.

Main outcome measures

Patient smoking cessation, knowledge of the perioperative risks of smoking, use of resources, and health care provider advice and assistance.

Results

Participants included 66 men and 95 women (mean [SD] age of 51.9 [14.0] years). In total, 7.5% of these patients quit smoking in the 8 weeks before their surgeries, although an additional 38.8% reduced their smoking. Only about half of the patients surveyed were aware that continuing to smoke increased their surgical risks. Further, only half of the patients surveyed reported being advised to quit before their surgeries by a health care professional. Few were using the provincial resources available to support smoking cessation (eg, QuitNow), and 39.6% were unaware of the provincial program to cover the cost of smoking cessation aids (eg, nicotine gum or patches), yet 62.7% of respondents were thinking about quitting smoking.

Conclusion

Many surgical patients in northern British Columbia who smoked were unaware of the perioperative risks of smoking and the cessation support available to them. An opportunity exists for all health care professionals to encourage more patients to quit in order to optimize their surgical outcomes.     

Cost–benefit analysis of percutaneous interventional radiological procedures in cancer patients

 The goal of this work was to evaluate the costs and benefits of percutaneous interventional radiological procedures (PIRP) in terminal cancer patients, from the perspective of the Radiodiagnostics Department. The subjects were 225 patients who underwent different kinds of treatments, such as placement of endovenous or urinary stents, percutaneous gastrostomy, alcoholization of metastatic disease, celiac plexus block, tumor embolization, and inferior vena caval filter. We retrospectively analyzed the consequences in terms of survival, quality of life and cost ratios and found that this study fully justifies the use of interventional radiology in palliative oncology: 60% and 40% of the patients, respectively, were still alive at 1 month and 3 months; the additional cost of PIRP procedures is low (<12%) compared with the total cost of hospitalization. Published online: 22 July 1999     

Ovariohysterectomy in the rat: a model of surgical pain for evaluation of pre-emptive analgesia?

Ovariohysterectomy in the rat led to the induction of abdominal postures and referred mechanical allodynia in the hind paws. The latter was differentiated into static and dynamic subtypes. The abdominal postures were present up to 4-5 h, whilst the two types of allodynia lasted for at least 2 days. A single administration of morphine 30 min before surgery dose-dependently (0.1-3 mg/kg, s.c.) blocked the development of abdominal postures and the two types of mechanical allodynia. The highest dose of morphine almost completely blocked these responses. The duration of action of 3 mg/kg morphine was short and similar (1.5-2 h) when administered either before or after surgery. However, multiple administrations of morphine (0.5 h before, and 0.5 and 2 h after surgery) blocked the development of abdominal postures and both allodynias for up to 2 days. In contrast, administration of three doses of morphine (3 mg/kg) in a similar dosing regime but starting 24 h after surgery, only blocked the two types of allodynia for 4 h. These data indicate the importance of blocking the induction phase of surgical pain and support the concept of pre-emptive analgesia. It is suggested that the ovariohysterectomy model should prove to be useful for studying mechanisms and designing novel therapeutic strategies for the treatment of post-operative pain.     

Diffusion-weighted MRI and PET–CT in the follow up of chronic periaortitis

Aim of the present study is to compare magnetic resonance imaging (MRI) and positron emission tomography (PET) parameters in the follow up of chronic periaortitis (CP), with a focus on changes in the apparent diffusion coefficient (ADC) and standardized uptake values (SUV). 127 patients with CP were treated in our urology between 2007 and 2017. We identified 14 patients with parallel abdominal MRI and PET–CT examinations before therapy and in the follow up resulting in a total of 56 examinations. Relative contrast uptake and diffusion-weighted MRI parameters were compared to SUV in the corresponding PET–CT examinationsand laboratory infection markers. All examined MRI and PET–CT parameters showed significant changes between basis and follow-up examinations. Median ADC values increased significantly (p?<?0.001) in the follow up. SUVmax and the other MR parameter (contrast uptake, DWI-signal) declined significantly. We observed a strong negative correlation between ADC and SUVmax (rho: ??0.61; p?<?0.001). In addition, we found an inverse correlation of ADC with the inflammation markers ESR (rho: ??0.64; p?<?0.001) and CRP (rho: ??0.54; p?=?0.001). MRI and PET–CT showed comparable results in the individual follow up of CP and compared to laboratory inflammation markers. Our data support MRI as first imaging modality due to absent radiation and the necessity of repetitive follow-up examinations in patients with CP.     

Functional MRI of the human amygdala?

In view of an increasing number of publications that deal with functional mapping of the human amygdala using blood oxygenation-level-dependent (BOLD) magnetic resonance imaging, we reevaluated the underlying image quality of T2*-weighted echoplanar imaging (EPI) and fast low angle shot (FLASH) sequences at 2.0-T with regard to susceptibility-induced signal losses and geometric distortions. Apart from the timing of the gradient echoes, the degree of susceptibility influences is controlled by the image voxel size. Whereas published amygdala studies report voxel sizes ranging from 22 to 125 microl, the present results suggest that reliable imaging of the amygdala with BOLD sensitivity requires voxel sizes of 4 to 8 microl or less. Preferentially, acquisitions should be performed with a coronal section orientation. Although high-resolution BOLD MRI is at the expense of temporal resolution and volume coverage, it seems to provide the only solution to this physical problem.