The current prevalence of superficial endometriosis is poorly understood, although it is the most common subtype of endometriosis. Moreover, its diagnosis is difficult, as the appearance and characteristics of the lesions it causes are not well known at the ultrasound level, so it is often necessary to perform a laparoscopy or histological study to confirm the diagnosis. This is why a group of researchers from several countries, including Dr Mª Angela Pascual and Dr Betlem Graupera, the Director of R&D and the Head of our Gynaecological Diagnostic Imaging Service (DGI), have carried out a prospective study to examine the lesions associated with this condition on the basis of images obtained by transvaginal ultrasound and to expand our current knowledge of their appearance and characteristics.

The study was conducted on 52 women with clinically suspected pelvic endometriosis who underwent preoperative transvaginal ultrasound and received a confirmed diagnosis of superficial endometriosis by laparoscopy. Women with deep endometriosis detected by ultrasound or laparoscopy were not included in the study.

The researchers observed that lesions caused by superficial endometriosis may appear as solitary lesions, multiple separate lesions and cluster lesions. They may also present associated hypoechogenic tissue, hyperechoic foci and/or velamentous adhesions). The lesion may be convex, protruding from the peritoneal surface, or may appear as a concave defect in the peritoneum. In general, most of the lesions had several of these characteristics.

The conclusion of the paper is that transvaginal ultrasound can be useful in diagnosing superficial endometriosis, and that the lesions have different ultrasound characteristics that can be described.