Ophthalmic artery Doppler as potential surrogate marker of angiogenic imbalance in near-term pregnancy.

OBJECTIVES

First, to evaluate whether the ratio of soluble fms-like tyrosine kinase-1 to placental growth factor (sFlt-1/PlGF) is associated with hemodynamic changes in ophthalmic artery (OA) Doppler in near-term pregnancy. Second, to assess the performance of OA Doppler to rule in and rule out angiogenic factor imbalance.

METHODS

This was a cross-sectional cohort study nested within the PE37 randomized controlled trial, involving nulliparous women recruited between January 2023 and January 2025 who underwent sFlt-1/PlGF ratio measurement between 35 + 0 and 36 + 6 weeks' gestation. We included a subsample of women who underwent OA Doppler evaluation, including measurement of OA peak systolic velocity (PSV) ratio and OA pulsatility index (PI), as well as assessment of mean arterial pressure (MAP) and mean uterine artery (UtA) PI. The operator was blinded to sFlt-1/PlGF ratio values. Trends in median values of OA and maternal-fetal Doppler parameters across sFlt-1/PlGF tertiles were analyzed using the Jonckheere-Terpstra test and quantile regression, adjusting for maternal body mass index, age and smoking status. The predictive performance of the OA-PSV ratio for sFlt-1/PlGF ratio ≥ 38 was evaluated using receiver-operating-characteristics-curve analysis.

RESULTS

We included 203 women, of whom 62, 71 and 70 were in the lowest, middle and highest tertiles of the sFlt-1/PlGF ratio, respectively. With increasing sFlt-1/PlGF ratio tertile, there was a significant increase in the OA-PSV ratio (median, 0.45 (interquartile range (IQR), 0.39-0.53) vs 0.48 (IQR, 0.41-0.58) vs 0.59 (IQR, 0.50-0.66); adjusted P < 0.001), a significant decrease in OA-PI (median, 2.20 (IQR, 1.92-2.61) vs 2.13 (IQR, 1.86-2.37) vs 1.86 (IQR, 1.60-2.26); adjusted P = 0.031) and a significant increase in MAP (median, 87.0 (IQR, 82.7-92.0) mmHg vs 88.7 (IQR, 83.7-93.7) mmHg vs 94.7 (IQR, 89.3-100.0) mmHg; adjusted P < 0.001). In contrast, no significant trend was observed in mean UtA-PI across sFlt-1/PlGF ratio tertiles. Among those individuals with an OA-PSV ratio < 0.61, 90.5% truly had a sFlt-1/PlGF ratio < 38, at a 15% false-positive rate.

CONCLUSIONS

This study provides new evidence of a significant association between the sFlt-1/PlGF ratio and OA Doppler parameters in near-term pregnancies, suggesting that OA Doppler indices, particularly the PSV ratio, reflect angiogenic imbalance. Given its non-invasive nature, accessibility and low cost, OA Doppler emerges as a promising surrogate tool for ruling out angiogenic imbalance. © 2026 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.