Clinical and ultrasound examinations in assessing parametria in patients with deep infiltrating endometriosis: a multicentre prospective study

To assess the performance of both clinical rectovaginal and transvaginal ultrasound examinations in the diagnosis of parametrial infiltration in patients with endometriosis, using surgery as reference standard. This is a multicentre prospective study. Patients with suspected deep endometriosis at clinical examination or ultrasound and scheduled for surgery were included. The following parameters were evaluated at clinical and ultrasound examinations: ovary fixity, vesicovaginal space, anterior and lateral parametria, uterosacral ligaments, retrocervix, and rectovaginal space. A consensus on methodology to define the parametrium at ultrasound and surgery was obtained following multicentre multidisciplinary meetings. Sensitivity, specificity, accuracy, positive (LR+) and negative (LR-) likelihood ratio were calculated. 195 consecutive women were selected and 164 of them were included in the final analysis. Ultrasound had good to high specificity (>80%) for all parameters except for left lateral parametrium (78.8%). The sensitivity was good to high for right and left ovary fixity, uterosacral ligaments, retrocervix, rectovaginal space and low for anterior and lateral parametrium, vagina, bladder and bowel. Clinical rectovaginal examination had good to high specificity for left ovary fixity, anterior parametrium, right uterosacral ligament, retrocervix, and vagina; and low for right ovary fixity, lateral parametria, left uterosacral ligaments and rectovaginal space. Sensitivity was good for uterosacral ligaments and rectovaginal space and low for the remaining parameters. Ultrasound examination provided good specificity for all the parameters, but the sensitivity was low for anterior and lateral parametria. Clinical examination provided good specificity for anterior and posterior parameters, but the sensitivity was low.