Ultrasound and PCOS

Abstract

Polycystic ovary syndrome (PCOS) is a common medical entity affecting up to 10 % of women of reproductive age. Until 2003, when polycystic ovarian morphology was included, the diagnosis of PCOS was based on the presence of clinical or laboratory evidence of hyperandrogenemia and chronic oligo- or anovulation. Despite the name of the syndrome, the polycystic ovarian morphology was not considered pathognomonic for the diagnosis. During the Consensus Workshop in Rotterdam, the sonographic evidence of polycystic morphology was recognized as equal diagnostic criterion of the syndrome and was further defined and simplified into the presence of either 12 or more follicles of 2-9 mm of diameter or an increased ovarian volume of more than 10 cm3. Thereafter, the technical refinement of the ultrasound equipment, the introduction of three-dimensional imaging, the rise of four distinct phenotypes of the syndrome, the connection of PCOS with metabolic disturbances and infertility implications, the results of well-designed studies, and, finally, the inherent trend for improvement of the clinical practice brought to the surface the necessity to fine-tune the definition of polycystic ovarian morphology. In this direction, there have been proposals to modify the threshold in the number of the antral follicles and the ovarian volume, according to the results of subsequent studies. Other researchers supported the role of three-dimensional screening as it provides better spatial perception and, consequently, more accurate follicle count. Additionally, 3D ultrasound offers the possibility to assess the degree of stromal echogenicity and vascularization that could be important features of the syndrome in combination with the peripheral distribution of the follicles. The substitution of ultrasound examination by anti-Mullerian hormone (AMH) measurement has also been proposed as a more precise method of evaluation of the ovarian function and reserve, especially in cases of controlled ovarian stimulation. All these controversies have been proven creative and will lead to a promising future of the ultrasound imaging in the diagnosis, definition, and treatment of the clinical manifestations of PCOS as acne, anovulation, and most importantly infertility.