Aims and objectives
Perianal fistulas represent a common inflammatory condition of the anal canal and perianal tissues.
Most of these fistulas occur due to idiopathic inflammation of the cryptogenic glands in the anal mucosa.
Less common causes include Crohn’s disease,
child birth related trauma or radiotherapy.
MRI allows the direct visualization of the fistulous tract,
its site and the extent of the fistula - and its abscess - in relation to the anal sphincters and levator ani muscle.
This has further improved the surgical outcome for these patients....
Methods and materials
Patients' Selection:
This prospective study included 38 patients with a total of 45 perianal fistulas and abscesses.
Inclusion criteria: Any patient with suspected perianal fistula or abscess,
eGFR ≥ 60 ml/min/1.73m2 and no contra-indication to IV gadolinium contrast or to MRI.
Exclusion criteria: Patients with contra-indication to gadolinium contrast or MRI,
e.g.
claustrophobia.
Patients with perianal abscesses who refused surgery - despite being indicated - were excluded from the study to avoid causing bias to the ADC analysis.
The decision of surgery was based solely...
Results
Demographic Analysis:
The study included 38 patients,
35 were males and 3 were females.
Mean age was 37 ± 8.9 years old with a range of 24 – 60 years of age.
The total number of perianal fistulas and abscess was 45.
These included 30 fistulas and 15 abscesses.
The sites of these fistulas/abscesses were inter-sphincteric (n = 25,
55.6%),
trans-sphincteric (n = 11,
24.4%) and extra-sphincteric (n = 9,
20%).
According to St.
James’s University Hospital classification,
there were 21 grade 1 fistulas,
4...
Conclusion
We concluded that DWI alone was not superior to T2W regarding the visibility of perianal fistulas and abscesses.
Although T2W evaluation detected higher number of fistulas,
yet this didn’t reach significant level.
The best performance was for combined DWI and T2W evaluation,
although it wasn’t significantly higher than either sequence alone.
We believe that DWI is better used as part of the entire MRI study,
i.e.
it should not replace T2W sequence.
We were able to confirm that DWI may be used as an alternative...
References
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