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Ophthalmic artery Doppler: reference values in low-risk pregnant women
Ladina Campana-Rüegg1,2, Martina Hofmann3,4, Julia Wawrla-Zepf3,4
1Department of Obstetrics, University Hospital Zurich, Frauenklinikstrasse 10, 8091, Zurich, Switzerland. ladina.campana-rueegg@usz.ch.
Insights
Ophthalmic artery (OA) Doppler indices, specifically the peak ratio (PR), provide stable reference values throughout pregnancy in low-risk women. These findings support OA-Doppler
Area of Science:
- Obstetrics and Gynecology
- Vascular Ultrasound
- Fetal Medicine
Background:
- Preeclampsia (PE) involves vasoconstriction, leading to altered ophthalmic artery (OA) waveforms.
- The second systolic peak (P2) and peak ratio (PR = P2/P1) of OA Doppler show promise in PE prediction and diagnosis.
- Establishing reference values for OA-Doppler indices in low-risk pregnancies is crucial for clinical application.
Purpose of the Study:
- To determine reference values for OA-Doppler indices (P1, P2, PR) during the 1st, 2nd, and 3rd trimesters, and at term.
- To assess the stability of these OA-Doppler indices in a low-risk, ethnically diverse European pregnant population.
Main Methods:
- Prospective single-center cohort study (2020-2024) including 255 healthy pregnant women.
- Exclusion of high-risk pregnancies or those developing PE.
- OA Doppler measurements performed at 4 gestational intervals: 11-14, 20-24, 30-34 GW, and term.
Main Results:
- The study included 255 women of diverse European ethnicity (62% Caucasian).
- The average peak ratio (PR) across all intervals was 0.56.
- No significant differences in PR were observed between the four gestational intervals or between the right and left eyes.
Conclusions:
- This study provides systolic OA-Doppler reference values for low-risk pregnant women in a diverse European population.
- OA-Doppler reference values, particularly PR, remain stable across different pregnancy stages.
- These stable reference values may facilitate future research into OA-Doppler's role in PE prediction and diagnosis.
Introduction:
Ophthalmic artery (OA) Doppler has been described as an independent parameter in predicting preeclampsia (PE). Considering that vasoconstriction occurs in the pathogenesis of PE and causes increased pulse wave reflection, it is not surprising that OA waveform changes appear in PE. It was found that of these waveform changes, the 2nd systolic peak (P2) and the peak ratio [PR = P2/P1 (P1 = 1st systolic peak)] showed the best performance in prediction and complementary diagnosis of PE. The aim of this study was to determine reference values for OA-Doppler indices in the 1st, 2nd, and 3rd trimesters and at term in low-risk pregnant women of a mixed European population.
Materials/Methods:
This is a prospective single-center cohort study conducted from 2020 to 2024. Only healthy pregnant women who gave informed consent were included. Women at high risk for PE or who developed PE were excluded. OA Doppler was performed according to a strict protocol at 4 distinct gestational-week (GW) intervals: 11-14 GW, 20-24 GW, 30-34 GW, and at term. The following systolic waveform parameters were focused on: P1, P2, and PR. Reference values were generated for these waveform parameters for these study intervals in the 1st, 2nd, and 3rd trimesters and at term.
Results:
A total of 255 women were included in this study. Of these, 62% were Caucasian, 7% Asian, 8% Afro-Caribbean, and 33% mixed or of unknown ethnicity. In this population, the PR averaged over the study intervals was 0.56, with no significant differences between the 4 study intervals or between the right and left eyes.
Conclusion:
This study presents systolic OA-Doppler reference values in low-risk pregnant women of an ethnically diverse European tertiary-care obstetric population. OA-Doppler reference values are stable throughout the four selected time points in pregnancy. These findings may pave the way for further investigations on OA-Doppler values as a predictive and diagnostic tool for PE.
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Pre-Procedural Guidelines for Doppler Ultrasound Blood Pressure Assessment:
Preparation of Equipment:
01:15Assessment of blood pressure in brachial artery(one-step method)
Prepare for the Procedure:
01:10Pre-Procedural Guidelines for Assessing Blood Pressure
01:21Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
01:23Assessment of blood pressure in brachial artery(two-step method)
01:28Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.