A comparison of endoscopic ultrasound, magnetic resonance imaging, and exam under anesthesia for evaluation of Crohn's perianal fistulas.
OBJECTIVE
To determine accuracy of endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) for evaluation of Crohn's disease perianal fistulas.


METHODS
Thirty-four patients with suspected Crohn's disease perianal fistulas were prospectively enrolled in a blinded study comparing EUS, MRI, and examination under anesthesia (EUA). Fistulas were classified according to Parks' criteria, and a consensus gold standard was determined for each patient. Acceptable accuracy was defined as agreement with the consensus gold standard for > or =85% of patients.


RESULTS
Three patients did not undergo MRI; 1 did not undergo EUS or EUA; and consensus could not be reached for 1. Thirty-two 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 > or =85%: EUS 29 of 32 (91%, confidence interval [CI] 75%-98%), MRI 26 of 30 (87%, CI 69%-96%), and EUA 29 of 32 (91%, CI 75%-98%). Accuracy was 100% when any 2 tests were combined.


CONCLUSIONS
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.
Schwartz
D A
DA
The Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Wiersema
M J
MJ
Dudiak
K M
KM
Fletcher
J G
JG
Clain
J E
JE
Tremaine
W J
WJ
Zinsmeister
A R
AR
Norton
I D
ID
Boardman
L A
LA
Devine
R M
RM
Wolff
B G
BG
Young-Fadok
T M
TM
Diehl
N N
NN
Pemberton
J H
JH
Sandborn
W J
WJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000758:Anesthesia; D003424:Crohn Disease / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000473:pathology; D011446:Prospective Studies; D012003:Rectal Fistula / Q000175:diagnosis* / Q000601:surgery; D012007:Rectum / Q000000981:diagnostic imaging; D014463:Ultrasonography