Presentation
Cyclic painful swelling of the right pelvic wall. History of cesarean section 8 years ago.
Patient Data
Ill-defined heterogeneously hypoechoic nodule of the right pelvic wall with irregular borders. No significant internal vascularity on the coulour Doppler.
Ill-defined deep subcutaneous soft tissue mass abutting the anterior margin of the right rectus abdominis muscle. It displays an isosignal to the muscles on T1, inhomogeneous high signal on T2 with central areas of high signal on T1/T1 fat sat and T2. The postcontrast sequences show moderate and heterogeneous enhancement. No extension to the underlying rectus abdominis muscle.
Small intramural leiomyoma (FIGO 4) is noted.
No ovarian or subperitoneal endometriosis.
Case Discussion
The clinical presentation, the ultrasound and CT features are most consistent with scar endometriosis.
Scar endometriosis occurs in a cesarian section scar. It can be located in the skin, subcutaneous tissue, rectus muscle/sheath, as well as intraperitoneally, or within the uterine scar. The reported incidence of scar endometriosis following cesarean section is about 0.03-0.6%.