Table 5 Comparison of diagnostic efficacy in both direct and indirect fistulography in the detection of primary tract, secondary tract internal orifice and secondary abscess collection
MRI imaging finding | Direct fistulography (%) | Indirect fistulography (%) |
|---|---|---|
Primary tract | ||
Sensitivity | 97.1 | 97.1 |
PPV | 94.3 | 91.7 |
Accuracy | 91.9 | 89.2 |
Secondary tract | ||
Sensitivity | 91.6 | 75 |
Specificity | 100.0 | 92.3 |
PPV | 100.0 | 81.8 |
NPV | 96.3 | 88.8 |
Accuracy | 97.37 | 86.8 |
Abscess collection | ||
Sensitivity | 60.0 | 100.0 |
Specificity | 100.0 | 100.0 |
PPV | 100.0 | 100.0 |
NPV | 87.1 | 100.0 |
Accuracy | 89.2 | 100.0 |
Internal orifices | ||
Sensitivity | 97.6 | 90.7 |
PPV | 95.3 | 95.1 |
Accuracy | 93.3 | 86.6 |