Comparative clinical evaluation of combine three-dimensional anorectal ultrasound and high-frequency linear array ultrasound versus MRI for diagnosis and postoperative outcomes of anal fistula

To evaluate and compare the diagnostic accuracy and postoperative outcomes of combined 3D-TRUS and HF-LAU versus MRI in the management of anal fistula. A retrospective analysis was conducted on 200 patients with anal fistula. Patients were divided into two groups: 105 individuals in the control group, who underwent Magnetic Resonance Imaging (MRI), and 95 individuals in the observation group, who were assessed using both 3D-TRUS and HF-LAU. Pathologic findings served as the reference. Diagnostic performance, including sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve, was compared between the two groups. The combined 3D-TRUS and HF-LAU method demonstrated superior diagnostic accuracy compared to MRI, with significantly better sensitivity and specificity (P < 0.05), with AUCs of 0.95 versus 0.89, respectively. The observation group showed significantly shorter postoperative hospitalization and recovery times, as well as a lower complication rate (P < 0.05). Postoperative incontinence and fistula recurrence were notably lower in the observation group (P = 0.017). Inflammatory markers showed no significant differences between the two groups (P > 0.05). The combined 3D-TRUS and HF-LAU method demonstrated superior diagnostic accuracy for detecting anal fistulas compared to MRI, highlighting its potential as a non-invasive, cost-effective alternative to MRI in settings that require high diagnostic precision.