Researchers from Rochester, Minnesota, USA, determined the accuracy of endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) for evaluation of Crohn's disease perianal fistulas.
A total of 34 patients with suspected Crohn's disease perianal fistulas were prospectively enrolled in the study.
In this, EUS, MRI, and examination under anesthesia (EUA) were all compared.
Fistulas were classified according to Parks' criteria, and a consensus gold standard was determined for each patient.
|Accuracy of modalities:|
Exam under anesthesia: 91%
| Gastroenterology |
Acceptable accuracy was defined as agreement with the consensus gold standard for ≥85% of patients.
Three patients did not undergo MRI; 1 did not undergo EUS or EUA; and consensus could not be reached for 1.
Some 32 patients had 39 fistulas (20 trans-sphincteric, 5 extra-sphincteric, 6 recto-vaginal, 8 others) and 13 abscesses.
The accuracy of all 3 modalities was found to be ≥85%: EUS 29 of 32 (91%), MRI 26 of 30 (87%), and EUA 29 of 32 (91%).
Accuracy was 100% when any 2 tests were combined.
Author David A. Schwartz, of the Mayo Clinic, Rochester, concluded on behalf of the rest of his team, "EUS, MRI, and EUA are accurate tests for determining fistula anatomy in patients with perianal Crohn's disease.
"The optimal approach may be combining any 2 of the 3 methods."