Deep endometriosis invading the bowel constitutes a major challenge for the gynecologist. In addition to the greater impact on pain, the high incidence of surgical morbidity involved with bowel endometriosis poses a therapeutic dilemma for the surgeon. Intestinal involvement by deep endometriotic nodules has been estimated to occur in 8–12% of women with endometriosis. Individual and clinical factors, pre-operative morphologic characteristics from imaging, surgical considerations and impact on quality of life are critical variables that should be considered in determining the best therapeutic strategy for a patient with deep endometriosis involving the sigmoid and/or the rectum. Pre-operative planning is fundamental for defining the optimal therapeutic strategy; patient counseling of treatment options, and when surgery is indicated, involvement of a multidisciplinary surgical team is required. The PubMed and Cochrane database were searched for all original and review articles published in English, French and Italian, until June 2014. Search terms included ‘deep endometriosis’, ‘surgical and clinical approach’, ‘bowel disease’, ‘quality of life’, ‘management of deep endometriosis’. Special attention was paid to articles comparing features of discoid and segmental resection. The rationale for the best therapeutic options for patients with deep endometriosis has been shown and an evidence-based treatment algorithm for determining when and which surgical intervention may be required is proposed. In deciding the best treatment option for patients with deep endometriosis involving the sigmoid and rectum, it is important to understand how the different clinical factors and pre-operative morphologic imaging affect the algorithm. Surgery is not indicated in all patients with deep endometriosis, but, when surgery is chosen, a complete resection by the most appropriate surgical team is required in order to achieve the best patient outcome. In women with deep endometriosis, surgery is the therapy of choice for symptomatic patients when deep lesions do not improve with a medical treatment.

BACKGROUND Successful surgical treatment of deep bowel endometriosis depends on obtaining detailed information about the lesions, prior to the procedure. The objective of this study was to determine the capability of transvaginal ultrasonography with bowel preparation (TVUS-BP) to predict the presence of one or more rectosigmoid nodules and the deepest bowel layer affected by the disease.