Vascularity of the urethra in continent women using colour doppler high-frequency endovaginal ultrasonography

OBJECTIVES: To assess the urethral vascularity in continent women using colour doppler high frequency endovaginal ultrasonography (EVUS). METHODS: We recruited 61 continent women attending gynaecology clinics between July and October 2009. Exclusion criteria included symptoms of urinary incontinence, voiding dysfunction, pelvic organ prolapse or urinary tract infection. The participants underwent EVUS using high frequency (9-12 MHz) biplane transducer (type 8848 BK Medical), according to a standardised protocol. Colour Doppler US was performed in sagittal plane and in transverse plane at the level of the mid-urethra. Ten seconds video files were recorded and following vascular parameters: flow velocity (V(mix)), area of the vessels (A(mix)), intensity of vascularity (I(mix)), pulsatility index (PI(mix)) and resistance index (RI(mix)) was evaluated. RESULTS: There were 30 nulliparous (49.2%) women and 31 multiparous women (50.8%) with a mean (±SD) age of 32 (±4) and 46 (±6) years respectively. Significant impairment of vascularity was observed in multiparous patients as compared to nulliparous and was reflected by increased values of RI(mix) (p < 0.001) and PI(mix) (p < 0.001), and decreased values of V(mix) (p < 0.001), A(mix) (p < 0.001), I(mix) (p < 0.001) in axial and midsagittal sections of the midurethra. A significant decrease of mean value ± SD of I(mix)- from 0.02 ± 0.02 in nulliparous to 0.005 ± 0.01 in multiparous was observed. Cronbach alpha, used to assess vascular correlations and parity demonstrated a reduction when expressed only for vascular parameters, indicating that number of deliveries is an important factor while assessing urethral vascularity. CONCLUSIONS: Compared to continent nulliparous women, continent multiparous women demonstrated a significant reduction in the vascularity parameters in all measured variables when parity was accounted for. ADVANCES IN KNOWLEDGE: This study provides the basis for further research in assessing urethral vascularity in women.