2002 The British Institute of Radiology
K LAKHANI, MSc, 2A M SEIFALIAN, MSc, PhD, 3W U ATIOMO, MD, MRCOG and 3 P HARDIMAN, MD, FRCOG
Ultrasound Department, X-Ray, North Middlesex Hospital, Sterling Way, Edmonton, London N18 1QX and University Department of Surgery and 3UniversityDepartment of Obstetrics and Gynaecology, Royal Free and University College Medical School, Pond Street, London NW3 2PF, UK
Abstract. Transvaginal ultrasound is currently the gold standard for diagnosing polycystic ovaries. The results of studies using ultrasound suggest a prevalence in young women of at least 20%. Between 5% and 10% of these women with polycystic ovaries shown on ultrasound willhave the classical symptoms of polycystic ovary syndrome such as infertility, amenorrhoea or signs of hirsutism and obesity, as originally described by Stein and Leventhal in 1935. However, the signiﬁcance of polycystic ovaries in asymptomatic women is still under investigation, as is the role of Doppler (pulsed and colour) and three-dimensional ultrasound. Ultrasound has also contributed to ourunderstanding of the local and systemic haemodynamic changes associated with polycystic ovaries, although the relationship of these changes to morbidity and mortality is unknown. The condition now known as polycystic ovarian syndrome (PCOS) was ﬁrst described by Stein and Leventhal in 1935  as comprising amenorrhoea, hirsutism, obesity and sclerotic ovaries. It is one of the most common humanendocrinopathies, affecting 5–10% of women of reproductive age . The diagnosis of PCOS was previously based on a combination of clinical and endocrine features, including raised serum concentrations of luteinizing hormone (LH), testosterone (T) and androstenedione and reduced levels of sex hormone binding globulin [3, 4]. With the introduction of pelvic ultrasound in the 1980s, non-invasiveassessment of ovarian morphology became possible. Ultrasound studies have demonstrated that approximately 20% of young women have polycystic ovaries (PCO) [5, 6], of whom around 25–70% have symptoms of infertility, menstrual irregularity or hirsutism, consistent with the diagnosis of PCOS [2, 5, 6]. However, the ﬁnding of PCO on ultrasound does not per se warrant such a diagnosis. More recently, highfrequency transvaginal ultrasound (TVS) has superseded transabdominal (TA) real-time scanning in the diagnosis of PCO because of its superior resolution, whilst three-dimensional (3D) imaging and colour Doppler blood ﬂow studies have allowed detailed evaluation of the stroma. The aim of this review article is to address the development of diagnostic ultrasound criteria of PCO with
Received 11 June2001 and in revised form 25 September 2001, accepted 16 October 2001. The British Journal of Radiology, January 2002
successive advances in ultrasound technology and to identify its salient associations.
Developments in ultrasound imaging
With advances in technology, in particular that of TVS, ultrasound has replaced laparotomy and X-ray pelvic pneumogynaecography in the diagnosis of PCO [7,8]. The static B-scanners of the mid 1960s allowed visualization of ovarian enlargement as well as of cysts measuring greater than 1 cm in diameter . The poor resolution of the ultrasound equipment used in the early 1970s permitted visualization of the ovarian outline only, and the diagnosis of PCO was based upon increased maximum length (.4.0 cm). However, the use of a single dimension maylead to false positive results when the full bladder compresses the ovary, or false negative results when the ovaries are spherical in shape. In fact PCO tend to be more spherical in shape so that the sphericity index (expressed as ovarian width to ovarian length ratio) is greater than 0.7 in PCO. A decreased uterine width to ovarian length ratio of greater than 1.0 has also been reported in the...