Predictive Value of Ultrasound Imaging for Diagnosis and Surgery of Deep Endometriosis: A Systematic Review.

OBJECTIVE: To calculate the predictive value and thus the clinical usefulness of transvaginal ultrasound (US) imaging for the management of deep endometriosis, knowing that the positive predictive value (PPV) varies with the prevalence and probably with the volume and location of the disease. DATA SOURCES: After registration on PROSPERO (CRD42022366323), PubMed was searched for all reports describing the diagnostic accuracy of US imaging for deep endometriosis published between January 1, 2000, and October 20, 2022. METHODS OF STUDY SELECTION: The 536 articles on "endometriosis AND US And diagnosis" were hand searched, and 30 reports describing sensitivity and specificity of deep endometriosis were found. Besides sensitivity and specificity, the prevalence, localization, and size of deep endometriosis lesions were collected. TABULATION, INTEGRATION, AND RESULTS: Prevalences of deep endometriosis were reported only twice as 12% and 32% by ultrasonographers. In women undergoing surgery, prevalences vary between 40% and 100% because of the variable inclusion criteria. Specificity is higher than sensitivity for all locations: rectovaginal (97% [86-100] vs 74% [31-95], p = .0002), rectosigmoid (97% [63-100] vs 88% [37-97], p = .0082), vesicouterine (100% [97-100] vs 63% [22-100], p = .0021), and uterosacrals (91% [77-99] vs 68% [18-83], p = .0005). Notwithstanding improved equipment, accuracy did not vary over the last 20 years. Sensitivities or specificities have not been stratified by the size of the lesion, and thus, the lower detection limits are not known. In the absence of blinding, the usefulness for surgery could not be established. CONCLUSION: The reported sensitivities and specificities of transvaginal US are not only those of imaging but include symptoms and clinical examinations. In referral centers, the reported PPVs are high (94%-100%) given that prevalences are >10% and specificities are >95%. However, the extrapolation of the clinical use before surgical interventions should be considered with care, given that PPVs for smaller lesions and the lower detection limit are unknown and surgeons were not blinded to US results.

Pathogenesis Based Diagnosis and Treatment of Endometriosis.

Understanding the pathophysiology of endometriosis is changing our diagnosis and treatment. Endometriosis lesions are clones of specific cells, with variable characteristics as aromatase activity and progesterone resistance. Therefore the GE theory postulates GE incidents to start endometriosis, which thus is different from implanted endometrium. The subsequent growth in the specific environment of the peritoneal cavity is associated with angiogenesis, inflammation, immunologic changes and bleeding in the lesions causing fibrosis. Fibrosis will stop the growth and lesions look burnt out. The pain caused by endometriosis lesions is variable: some lesions are not painful while other lesions cause neuroinflammation at distance up to 28 mm. Diagnosis of endometriosis is made by laparoscopy, following an experience guided clinical decision, based on history, symptoms, clinical exam and imaging. Biochemical markers are not useful. For deep endometriosis, imaging is important before surgery, notwithstanding rather poor predictive values when confidence limits, the prevalence of the disease and the absence of stratification of lesions by size, localization and depth of infiltration, are considered. Surgery of endometriosis is based on recognition and excision. Since the surrounding fibrosis belongs to the body with limited infiltration by endometriosis, a rim of fibrosis can be left without safety margins. For deep endometriosis, this results in a conservative excision eventually with discoid excision or short bowel resections. For cystic ovarian endometriosis superficial destruction, if complete, should be sufficient. Understanding pathophysiology is important for the discussion of early intervention during adolescence. Considering neuroinflammation at distance, the indication to explore large somatic nerves should be reconsidered. Also, medical therapy of endometriosis has to be reconsidered since the variability of lesions results in a variable response, some lesions not requiring estrogens for growth and some being progesterone resistant. If the onset of endometriosis is driven by oxidative stress from retrograde menstruation and the peritoneal microbiome, medical therapy could prevent new lesions and becomes indicated after surgery.