Scar endometriosis is a term given to endometriosis occurring in a Caesarian section scar. It can be located at the skin, subcutaneous tissue, rectus muscle/sheath, intraperitoneally, or in the uterine myometrium (within uterine scar).
The reported incidence of abdominal scar endometriosis following Cesarean section the incidence is 0.03-0.6% 6.
Patients may complain of tenderness to palpation and a raised, unsightly hypertrophic scar. Most patients have cyclical pain (up to 70%) 5. The pain is usually intermittent and associated with the patient's menstrual cycle but it may be constant in nature. Some reports state that even as low as 20% of the patients exhibited cyclical symptoms. The overlying skin may be hyper-pigmented due to deposition of haemosiderin. Some patients may be asymptomatic 4.
It is thought to be caused by implantation of endometrial stem cells at the surgical site at the time of uterine surgery.
For general imaging features of endometriosis: refer to the parent article.
Sonographic features are not specific. A subcutaneous nodule having relatively irregular borders, a heterogeneous echotexture with internal scattered hyperechoic echoes surrounded by a hyperechoic ring of variable width, and vascularity may be present. Occasionally cystic changes may be present 6.
Well defined soft tissue nodule with heterogenous post-contrast enhancement and streakiness in the surrounding tissue.
Is the most sensitive imaging modality. Often accurately locates the lesion in relation to a previous C section scar, with signal characteristics similar to that of background endometriosis.
- 1. Gajjar KB, Mahendru AA, Khaled MA. Caesarean scar endometriosis presenting as an acute abdomen: a case report and review of literature. Arch. Gynecol. Obstet. 2008;277 (2): 167-9. doi:10.1007/s00404-007-0431-4 - Pubmed citation
- 2. Wolf GC, Kopecky KK. MR imaging of endometriosis arising in cesarean section scar. J Comput Assist Tomogr. 13 (1): 150-2. - Pubmed citation
- 3. Balleyguier C, Chapron C, Chopin N et-al. Abdominal wall and surgical scar endometriosis: results of magnetic resonance imaging. Gynecol. Obstet. Invest. 2003;55 (4): 220-4. doi:10.1159/000072078 - Pubmed citation
- 4. Gidwaney R, Badler RL, Yam BL et-al. Endometriosis of abdominal and pelvic wall scars: multimodality imaging findings, pathologic correlation, and radiologic mimics. Radiographics. 2012;32 (7): 2031-43. doi:10.1148/rg.327125024 - Pubmed citation
- 5. Ozel L, Sagiroglu J, Unal A et-al. Abdominal wall endometriosis in the cesarean section surgical scar: a potential diagnostic pitfall. J. Obstet. Gynaecol. Res. 2012;38 (3): 526-30. doi:10.1111/j.1447-0756.2011.01739.x - Pubmed citation
- 6. Hensen JH, Van breda vriesman AC, Puylaert JB. Abdominal wall endometriosis: clinical presentation and imaging features with emphasis on sonography. AJR Am J Roentgenol. 2006;186 (3): 616-20. doi:10.2214/AJR.04.1619 - Pubmed citation
- 7. Danielpour PJ, Layke JC, Durie N et-al. Scar endometriosis - a rare cause for a painful scar: A case report and review of the literature. Can J Plast Surg. 2011;18 (1): 19-20. Free text at pubmed - Pubmed citation