Table 2 MR imaging findings of PID. DWI diffusion-weighted imaging, ADC apparent diffusion coefficient
| Tubo-ovarian disease | Morphology | T2 | T1 | Gd–T1 | DWI | ADC | Differential diagnoses |
|---|---|---|---|---|---|---|---|
| Hydrosalpinx | Fluid filled thin-walled tubular structure |
 High |
 Low |
 No enhancement |
 Low |
 No restriction | - Multilocular cystic adnexal masses |
| Haematosalpinx | Dilated fallopian tube filled with blood products |
 Intermediate with dark thick rim, possible “shading sign” in endometriosis |
 High |
 Slight enhancement of the tubaric wall |
 High |
 Restriction |
- Endometriosis - Ectopic Pregnancy - Adnexal torsion - Trauma - Malignancy |
| Acute salpingitis | Swollen fallopian tube with intramural inflammation |
 Wall thickening of the distended tube |
 Low |
 Wall enhancement |
 High signal of the wall |
 Restriction of the wall | |
| Pyosalpinx | Bilateral, serpiginous or tubular structure with purulent content and possible fluid-debris levels |
 Iso-hyperintense |
 Variable |
 Enhancement of the thickened wall |
 High |
 Restriction | |
| Tubo-ovarian abscess | Loss of the normal adnexal structure, formation of a solid-cystic pus-filled inflammatory mass |
 Heterogeneous high signal |
 Heterogeneous low signal |
 Septal and thick rim mucosal enhancement |
 High signal of the wall, septa and purulent content |
 Restriction of the wall, septa and purulent content |
- Ovarian carcinoma - Primary fallopian tube carcinoma |