High frequency probe combined with end scan convex array intracavitary probe transperineal ultrasonography in diagnosing anal fistula / 中国医学影像技术

ABSTRACT

Objective: To explore the value of high frequency probe combined with end scan convex array probe transperineal ultrasonography for diagnosis of anal fistula. Methods: Data of 87 patients with anal fistula who underwent surgical treatment were retrospectively analyzed. All patients were examined with ultrasonography using 5-12 MHz linear array probe combining with palpation and visual examination for detection of external mouth and fistula before operation, also perineum ultrasound using 3-10 MHz end scan convex array probe for detection of internal mouth and typing and location of anal fistula. The consistency between results of ultrasound and surgical operation was analyzed. Results: Among 87 patients, 73 cases were diagnosed as simple anal fistula and 14 as complex anal fistula, with a total of 93 internal mouths, 101 fistula canals and 94 internal mouths were detected with surgical operation. Ultrasound correctly diagnosed anal fistula in 66 patients, missed anal fistula in 15 cases and misdiagnosed 6 cases, the coincidence rate of ultrasound and operation was 75.86% (66/87), the Kappa value was 0.344 (P<0.001).The accuracy of ultrasonography in diagnosing internal mouth, fistula canal and external mouth of anal fistula was 80.65% (75/93), 83.17% (84/101) and 87.23% (82/94), respectively, the Kappa value of consistency with operation results was 0.298, 0.407 and 0.626, respectively (all P<0.001). Conclusion: High frequency probe combined with end scan convex array probe transperineal ultrasonography is helpful to diagnosis of anal fistula.