Recto-vaginal deep infiltrating endometriosis (DIE) is defined by the presence of endometrial tissue, muscle hyperplasia and fibrosis of more than 5 mm in depth located on the rectovaginal septum. The most common described DIE locations are uterosacral ligaments, rectosigmoid, the vagina and the bladder. Often patients with DIE report symptoms such as chronic pelvic pain, dysmenorrhea and dyspareunia. The presence of DIE in the vagina is rare, accounting for 5-10% of cases of endometriosis. The etiology is attributed to endometrial tissue metaplasia of group of cells of the recto-vaginal septum.
Vaginal endometriosis is classified as superficial and deep. Superficial vaginal endometriotic implants are usually located in the vaginal fornix and have no association with DIE of the recto-vaginal septum. Deep vaginal endometriosis is more common; it is usually associated with endometriosis of the recto-vaginal septum and appears as nodule or polyp in the posterior vaginal fornix between the insertion of the uterosacral ligaments. The nodules may have cystic areas of brownish or bluish color due to the presence of retained blood components. This type of lesions usually goes unnoticed during hysteroscopy.
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