"induction theory: whereby shed endometrium releases substances that induce undifferentiated mesenchyme to form endometriotic tissue 2"
"lesions can vary in size from a few millimetres to several centimetres."
"Many professional groups and organisations recommend the term deep endometriosis over the older term deep infiltrating endometriosis (DIE)35-37, although the latter remains widely used 24,25,30."
"Many professional groups and organisations recommend the term deep endometriosis over the older term deep infiltrating endometriosis (DIE)35-37, although the latter remains widely used 24,25,30."
"most common location to see deep endometriosis on TV ultrasound"
"diagnostic criteria: multiple cysts with T1 hyperintensity OR one or more cysts with high T1 and shading on T2 1,19"
"Malignant transformation of endometriosis, most often of an endometrioma, is rare and usually progresses to endometrioid carcinoma or, less commonly, clear cell carcinoma. Although endometriosis is associated with an increased relative risk of ovarian cancer, the absolute risk is low, and the 2022 ESHRE guideline recommends against routine surveillance imaging or cancer screening beyond that of the general population 37."
Expected headings
"Symptoms"
"Examination findings"
"Location"
"Associations"
"Transabdominal ultrasound"
"Transvaginal ultrasound"
"Contrast-enhanced ultrasound (CEUS)"
"Limitations of MRI"
"Medical treatment"
"Surgery"
"Complications"
"The pathogenesis of endometriosis remains unclear and is subject to much debate; potential mechanisms include:"
"metastatic theory: transplantation of endometrial cells (via retrograde menstruation, lymphatic or vascular dissemination, iatrogenic implantation) with probable immune/hormonal/inflammatory mediators 8; supporting this theory is that ~75-90% of women have bloody peritoneal fluid during the perimenstrual period 9"
"the amount of pigment appears to increase with the age of the lesion: initially, they appear as white plaques, non-pigmented clear vesicles, or red petechiae or flame-like areas; as they age, the colour changes to bluish/brownish lesions - these are referred to as “powder burns”, representing haemolysed blood encased in fibrotic tissue 11"
"nodules on the serosal surface of the uterus may appear as solid, hypoechoic masses; these can be difficult to differentiate from fibroids"
"ureters: may appear dilated with deep endometriosis; dilatation of the ureter due to endometriosis is caused by stricture (from either extrinsic compression or intrinsic infiltration)"
"can be obliterated due to adhesions; should be assessed with the sliding sign (like the pouch of Douglas)"
"hypoechoic nodule with regular or irregular margins is seen within the peritoneal fat surrounding the uterosacral ligament; the lesion may be isolated or may be part of a larger nodule extending into the vagina or into other surrounding structures"
"nodules can be single or multifocal; a second or subsequent rectal lesions have been demonstrated to occur in 55% of cases 27"
"endometriotic implants with intestinal involvement present as an extraluminal growth from the serosa to the innermost layers, with preservation of the layered structure of the intestinal wall; these findings allow differentiation from intestinal neoplasia since the latter presents a growth from the mucosal layer towards the most external layers and is associated with loss of the layered structure of the intestinal wall"
"metastatic theory: transplantation of endometrial cells (via retrograde menstruation, lymphatic or vascular dissemination, iatrogenic implantation) with probable immune/hormonal/inflammatory mediators 8; supporting this theory is that ~75-90% of women have bloody peritoneal fluid during the perimenstrual period 9"
"invade adjacent structures, most commonly the uterosacral ligaments, torus uterinus, rectovaginal septum, posterior vaginal fornix, rectosigmoid and bladder wall 12"
"associated with adhesions, retraction and distortion of normal anatomy, including obliteration of the pouch of Douglas 35"
"the appearance of nodules can vary, including hypoechoic linear or spherical lesions, with or without regular contours, involving the muscularis (most common) or (sub)mucosa of the bladder"
"a discrete hypoechoic nodule in the vaginal wall which may be homogeneous or inhomogeneous, with or without large cystic areas, and there may or may not be cystic areas surrounding the nodule"
"inflammatory response due to repeated haemorrhage can lead to adhesions, strictures and bowel obstructions"
"abdominal wall and recesses (e.g. inguinal hernias / umbilical region - umbilical endometriosis)"
"The use of CEUS in deep pelvic endometriosis can be useful to assess the preservation of the layered structure of the intestinal wall (differentiating it from intestinal neoplasia), to define the extension and morphology of the implant, and to assess an extrinsic origin in cases of ureteric involvement (differentiating it from urothelial neoplasia). In cases of deep endometriosis compressing the ureter or causing hydronephrosis, CEUS can also help assess whether an enhancing lesion in the ureter has an intraluminal (as seen in urothelial neoplasms) or an extraluminal origin (as seen in endometriotic implants) 28."