# Efficacy evaluation of ultrasound-derived fat fraction in predicting of the severity of women with polycystic ovary syndrome and obesity

## TL;DR

This study shows that ultrasound-derived fat fraction (UDFF) can help predict the severity of polycystic ovary syndrome in obese women.

## Contribution

The study introduces UDFF as a novel ultrasound-based index for evaluating PCOS severity in obese women.

## Key findings

- Women with PCOS and obesity had significantly higher UDFF values compared to controls.
- UDFF correlated with glucose-lipid metabolism, sex hormones, ovarian morphology, and blood flow parameters.
- A multivariate model using UDFF and other factors achieved an AUC of 0.913 in predicting PCOS severity.

## Abstract

To investigate the feasibility of ultrasound-derived fat fraction (UDFF) as an evaluation index for obese women with polycystic ovary syndrome (PCOS).

A total of 103 Women with PCOS and obesity (case group) and 108 Women without PCOS but with obesity (control group) were enrolled. All participants underwent transvaginal three-dimensional ultrasound examination on the 7th day of their menstrual cycle. General data, biochemical parameters, sex hormones, ovarian volume, follicle count, ultrasound blood flow indices, hepatic UDFF, and shear wave velocity (SWV) were collected from both groups. Comparisons were made between the case group and the control group regarding UDFF, SWV, ovarian morphological indices, ovarian stromal blood flow parameters, clinical characteristics, serum biochemical indices, and sex hormone levels. Logistic regression analysis was used to identify risk factors for the case group, and Spearman correlation analysis was performed to assess the correlations between UDFF and various variables.

Compared with the control group, Women with PCOS and obesity had significantly higher values of the UDFF, Quantity of follicle, Luteinizing Hormone (LH), LH/FSH ratio, Estradiol (E2), Peak Systolic Velocity (PSV) of ovarian stromal arteries, End Diastolic Velocity (EDV) of ovarian stromal arteries, vascularization index (VI),(Vascularity Index, VI: Reflecting the richness of blood vessels within the detection area, it is a core parameter for assessing the level of angiogenesis using power Doppler ultrasound;) blood flow index (FI),(Flow Index, FI: It reflects the average intensity of blood flow signals within the detection area and has a certain correlation with blood flow velocity and volume;)vascularization-flow index (VFI),(Vascular Flow Index, VFI: By combining the comprehensive indicators of VI and FI, the vascular richness and blood perfusion intensity of the detection area can be comprehensively evaluated) Low-Density Lipoprotein (LDL), abdominal circumference, Triglyceride (TG), fasting blood glucose and Homeostatic model assessment-insulin resistance (HOMA-IR) (all P < 0.05). In contrast, Women with PCOS and obesity showed significantly lower SWV, Follicle-Stimulating Hormone (FSH),Resistance Index (RI),(Resistance Index, RI: The calculation formula is (systolic peak flow velocity—end diastolic flow velocity)/systolic peak flow velocity;) Pulsatility Index (PI)(Pulsatility Index, PI: The calculation formula is (systolic peak velocity—end diastolic velocity)/mean velocity.) (all P < 0.05). Logistic regression analysis revealed that SWV, VFI, UDFF, RI, and LDL were independent risk factors for Women with PCOS and obesity. The ROC curve showed that the area under the curve (AUC) of the multivariate model was 0.913. Spearman correlation analysis indicated that UDFF was correlated with SWV, ovarian morphological indices, ovarian stromal blood flow parameters, clinical characteristics, serum biochemical indices, and sex hormone levels.

Women with PCOS and obesity have higher UDFF values than the control group. UDFF is correlated with glucose-lipid metabolism, sex hormone indices, ovarian morphology, and hemodynamic parameters, suggesting that UDFF can predict the severity of PCOS to a certain extent.