title: Three-dimensional ultrasound features of the polycystic ovary and the effect of different phenotypic expressions on these parameters.
abstract: BACKGROUND
  The aim of this study was to quantify the three-dimensional (3D) ultrasound characteristics of ovaries in Caucasian women with polycystic ovarian syndrome (PCOS) and to examine if these values differed between different phenotypic forms.
  
  
  METHODS
  3D pelvic ultrasound was performed in 40 women with PCOS and in 40 controls. Total ovarian volume, stromal volume and echogenicity and antral follicle count (AFC) were measured and ovarian blood flow was quantified using both 3D power Doppler and two-dimensional pulsed-wave Doppler.
  
  
  RESULTS
  Women with PCOS had a higher AFC (median 16.3 versus 5.5 per ovary, P < 0.001) and ovarian volume (12.56 versus 5.66 ml, P < 0.001). Stromal volume (10.79 versus 4.69 ml, P < 0.001) and stromal vascularization (VI: 3.85 versus 2.79%, P < 0.001; VFI: 1.27 versus 0.85, P < 0.001) were also increased in women with PCOS. There were no significant differences in stromal echogenicity or pulsed-wave Doppler indices between women with PCOS and the controls. Among the women with PCOS, ovarian vascularity was significantly higher in 30 women who were hirsute compared with normoandrogenic women (FI: 33.94 versus 29.30, P < 0.05) and in 14 women with PCOS who were of normal weight compared with obese women (VI: 4.51 versus 3.25%, P < 0.05; VFI: 1.56 versus 1.22, P < 0.05).
  
  
  CONCLUSIONS
  Based on 3D ultrasound, women with PCOS have an increased stromal volume and vascularity. Stromal vascularity is significantly higher in women with PCOS who are hirsute and of normal weight.
authors.affiliation: Department of Obstetrics and Gynaecology, The Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China. lampomui@cuhk.edu.hk
authors.forename: Po M
authors.initials: PM
authors.lastname: Lam
authors.forename: Ian R
authors.initials: IR
authors.lastname: Johnson
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Raine-Fenning
mesh_terms: D000328:Adult; D001835:Body Weight; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007247:Infertility, Female / Q000000981:diagnostic imaging*; D015588:Observer Variation; D010053:Ovary / Q000098:blood supply / Q000000981:diagnostic imaging*; D010641:Phenotype; D011085:Polycystic Ovary Syndrome / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D018608:Ultrasonography, Doppler / Q000379:methods* / Q000706:statistics & numerical data