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.

Sciatica: An Extremely Rare Complication of the Perianal Abscess.

BACKGROUND: Sciatica has been classically described as pain in the back and hip with radiation in the leg along the distribution of the sciatic nerve, secondary to compression or irritation of the sciatic nerve. Spinal abnormality being the most common etiology, is one of the most common indications for MRI of the lumbosacral spine. Here we describe imaging findings secondary to a supralevator perianal abscess causing irritation of the sciatic nerve, which was diagnosed on MRI of the lumbosacral spine. CASE REPORT: A 47-year-old male patient presented to the emergency department with severe acute pain in the right hip and right leg which was aggravated by limb movement. Clinically, a possibility of sciatica was suggested and MRI of the lumbosacral spine was ordered. The MRI did not reveal any abnormality in the lumbosacral spine; however, on STIR coronal images, a right perianal abscess with air pockets was seen. The perianal abscess was extending above the levator ani muscle with and was seen tracking along the sciatic nerve, explaining pain along the distribution of the sciatic nerve. The abscess was surgically drained, followed by an antibiotic course. The patient was symptomatically better post-surgery. Post-operative scan done 3 days later revealed significant resolution of the infra- and supralevator perianal abscess. The patient was discharged from hospital on post-operative day 3 on oral antibiotics for 7 days. On 15th post-operative day, the patient was clinically completely asymptomatic with good healing of the perianal surgical wound. CONCLUSIONS: Extra-spinal causes are rare and most often overlooked in patients with sciatica. While assessing patients with sciatica, extra-spinal causes for the radiation of pain along the distribution of the sciatic nerve should always be looked for if abnormalities in the MRI of the lumbar spine are not found. Inclusion of STIR sequences in the imaging of the lumbosacral spine, more often than not, helps to identify the extra-spinal cause of sciatica when MRI of the lumbosacral spine does not reveal any abnormality.

Magnetic Resonance Imaging (MRI) Characterization of Perianal Fistulous Disease in a Rural Based Tertiary Hospital of North India.

BACKGROUND: To diagnose and characterize the perianal fistulous disease using Magnetic resonance imaging (MRI) in a hilly and rural area of North India. MATERIAL/METHODS: This prospective hospital based study was conducted for a period of one year from April 2014 to April 2015 in the departments of Radiodiagnosis and Surgery of our institute. A total of 50 consecutive patients presenting with perianal fistulous disease fulfilling the inclusion and exclusion criteria were included in the study and taken up for MRI. The perianal fistulae were classified according to St James University hospital classification and tracks were assessed with regard to anatomical plane, length, ramifications, abscess formation, enteric communication, external cutaneous opening, enhancement and suprasphincteric extension. Surgical correlation was done in 31 patients who opted for surgical treatment. Rest of the 19 patients preferred alternative medicine for treatment or chose to postpone their surgery. RESULTS: The disease was much more prevalent in males in comparison to females with male to female ratio of 24:1. Grade 4 was the most common type of fistula (34%) while Grade 5 was the least common type (4%).MRI showed a high sensitivity of 93.7% and positive predictive value (PPV) of 96.7% when correlated with surgical findings. A substantial number of patients (38%) preferred alternative medicine or non surgical form of treatment. CONCLUSIONS: MRI is a very sensitive modality for the evaluation of perianal fistula. In our study group, the disease predominantly affected middle aged men. Ramifications and abscesses were commonly seen, affecting nearly half of the patients and majority of the patients had active fistulous tracks with posteriorly located enteric opening. Overall, transsphincteric fistulae were most common. Significant number of patients avoided surgery or showed preference for non surgical treatment.

A retrospective analysis of 93 cases with anorectal abscess in a rural state hospital.

OBJECTIVE: Anorectal abscess is a clinical condition frequently encountered in daily surgical practice and recurrences may occur despite treatment with adequate incision and drainage. The primary aim of this study was to analyze the variables that may have resulted in recurrent anorectal abscess, retrospectively. MATERIAL AND METHODS: Ninety-three patients out of 149 patients who underwent surgery for anorectal abscess at our center between 2011-2012 were included in this study. Data regarding age, gender, presence of recurrence, time to recurrence, abscess type, presence of fistula, fistula type, drain usage, length of hospital stay and follow-up duration were retrospectively recorded. RESULTS: Patients were divided into two groups: the recurrence group and the treatment group. Eleven patients (11.8%) had a recurrence and the median time to recurrence was 3 months. None of the variables evaluated were found to be significantly associated with the presence of recurrence. CONCLUSION: Variables such as age, gender, type of abscess, presence of fistula or drain usage were not associated with the development of recurrence in patients who underwent incision and drainage of an anorectal abscess.

Ulceración perianal: Dos casos de una rara manifestación de tuberculosis extrapulmonar / Perianal tuberculosis: Report of two cases

Perianal tuberculosis is an uncommon variant of extra pulmonary tuberculosis and mimics other common perianal conditions. We report two patients with perianal tuberculosis. An 82-year-old male presenting with purulent perianal discharge and weight loss. A pelvic magnetic resonance imaging showed a low trans sphincteric anorectal fistula with abscess formation. A fistulectomy was performed and the pathological study showed a granulomatous-tuberculous chronic inflammation. Mycobacteria were recovered from gastric contents. A 48-year-old male with the same symptoms. An ulcerated lesion in the anal region was biopsied, disclosing a granulomatous inflammatory process with Ziehl-Nielsen stainable organisms.