Impact of three-dimensional endoanal ultrasound on the outcome of anal fistula surgery: a prospective cohort study.
OBJECTIVE
The aim of the study was to evaluate the impact of three-dimensional endoanal ultrasound (3D-EAUS) on postoperative outcome in patients with anal fistula.


METHODS
This prospective study compared clinical and functional outcomes of patients with and without preoperative 3D-EAUS examination 1 year after anal fistula surgery. Patients were prospectively followed and evaluated by a standardized protocol including physical examination, the Wexner Incontinence Score (WIS) and anorectal manometry, at baseline and 1 year after surgery.


RESULTS
A total of 196 patients were enrolled. There were no significant differences in demographic and operative parameters, except for operation time, between the two groups. At 1 year follow-up, the overall recurrence rates were 8.8% (9/102) in the 3D-EAUS group and 13.8% (13/94) in the examination under anaesthesia (EUA) group. In the subgroup of patients with complex fistulae, the recurrence rate was numerically lower in the 3D-EAUS group (12.8% vs 22.5%; P = 0.26). The WIS in the EUA group significantly worsened (0.35 ± 0.94 vs 1.07 ± 1.59; P = 0.003) with a decreased the number of fully continent patients (82.5% vs 55%; P = 0.008) while neither the WIS nor the proportion of fully continent patients changed in the 3D-EAUS group. Fewer patients in the 3D-EAUS group developed incontinence postoperatively (6.7% vs 33.3%; P = 0.012) and they had better maximum resting pressure and maximum squeeze pressure than the EUA group.


CONCLUSIONS
Preoperative use of 3D-EAUS had a favourable impact on the outcome of surgical treatment for anal fistulae, especially in those with complex anal fistula. It should be routinely used in the clinical setting.
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
J-H
JH
Ding
Department of Medicine, Second Artillery General Hospital, Beijing, China.
L-X
LX
Bi
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
K
K
Zhao
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
Y-Y
YY
Feng
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
J
J
Zhu
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
B
B
Zhang
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
S-H
SH
Yin
Department of Colorectal Surgery, Colorectal Disease Center of PLA, Beijing, China.
Y-J
YJ
Zhao
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D019160:Endosonography / Q000379:methods*; D005242:Fecal Incontinence / Q000209:etiology / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology; D011446:Prospective Studies; D012003:Rectal Fistula / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D012008:Recurrence; D016896:Treatment Outcome; D055815:Young Adult
Ultrasound; fistula; incontinence; recurrence