Ophthalmic artery Doppler at 35-37 weeks' gestation in pregnancies with small or growth-restricted fetuses

Ultrasound Evaluation of the Changes of Ophthalmic Artery Doppler and Optic Nerve Sheath in Pregnant Women With FGR

OBJECTIVES

This study aimed to compare changes in ultrasonic Doppler parameters, particularly the peak ratio (PR) of the ophthalmic artery (OA) and optic nerve sheath diameter (ONSD), in pregnancies complicated by fetal growth restriction (FGR). Furthermore, it sought to evaluate differences in these parameters across various subgroups and analyze the cut-off value of PR for predicting delivery within 1 week in pregnancies complicated by FGR.

METHODS

A total of 62 pregnant women in the mid-to-late stages of gestation were enrolled, comprising 31 participants in the FGR group and 31 in the control group. The general conditions, pregnancy outcomes, Doppler parameters of the OA, and ONSD were compared between the two groups. Comparative analysis was performed to investigate differences in OA Doppler parameters and ONSD across FGR subgroups. The predictive value of PR for delivery within 1 week was assessed using the area under the receiver operating characteristic curve.

RESULTS

The PR of the OA was significantly elevated in the FGR group compared to the control group, demonstrating a statistically significant difference. The threshold PR value for predicting delivery within 1 week was 0.565, with a sensitivity of 0.88 and a specificity of 0.58.

CONCLUSIONS

The PR value of the OA in pregnant women with FGR is significantly increased and may serve as a reliable predictor for pregnancies complicated by FGR.

Ophthalmic Artery Doppler as a Predictor of Adverse Neonatal Outcomes in Women With Preeclampsia

OBJECTIVE

This study aimed to evaluate the association between ophthalmic artery (OA) Doppler indices and adverse neonatal outcomes in women with pregnancies complicated by preeclampsia (PE).

METHODS

A prospective cross-sectional study involving 110 pregnant women who were diagnosed with PE in the first 24 h of hospitalization was conducted at three hospitals in southeastern Brazil from April 2020 to December 2022. The ophthalmic parameters analyzed were the resistance index (RI), pulsatility index (PI), first peak systolic velocity (PSV1), second peak systolic velocity (PSV2), ratio of PSV2 to PSV1 (PSV ratio or the peak ratio [PR]), and end-diastolic velocity (EDV). The outcome measures were neonatal death (during hospitalization), neonatal intensive care unit (ICU) admission, gestational age at delivery < 32 weeks, birth weight < 1500 g, birth weight < 10th percentile, the presence of comorbidities associated with prematurity, the use of invasive mechanical ventilation, an Apgar score at the 5th minute < 7.0, and signs of neurological impairment.

RESULTS

Pregnant women with severe features of PE showed higher values of systolic (152.8 ± 20.7 vs. 136.3 ± 11.9, p = 0.000) and diastolic (98.1 ± 12.8 vs. 88.1 ± 10.8, p = 0.000) blood pressure values and lower gestational age at admission (31.5 ± 3.8 vs. 33.7 ± 4.3, p = 0.009) than PE without severe features. No significant differences were found between the mean values of the OA Doppler indices when comparing the presence or absence of neonatal outcomes in the women with PE.

CONCLUSIONS

OA Doppler, while valuable for the prediction, diagnosis, and evaluation of adverse maternal outcomes, does not independently predict adverse neonatal outcomes in women with severe features of PE.

Constructing small for gestational age prediction models: A retrospective machine learning study

OBJECTIVE

To develop machine learning prediction models for small for gestational age with baseline characteristics and biochemical tests of various pregnancy stages individually and collectively and compare predictive performance.

STUDY DESIGN

This retrospective study included singleton pregnancies with infants born between May 2018 and March 2023. Small for gestational age was defined as a birth weight below the 10th percentile according to the Intergrowth-21st fetal growth standards. The pregnancy data were categorized into four datasets at different gestational time points (14 and 28 weeks and admission). The LightGBM framework was utilized to assess the variable importance by employing a five-fold cross-validation. RandomizedSearchCV and sequential feature selection were applied to estimate the optimal number of features. Seven machine learning algorithms were used to develop prediction models, with an 8:2 ratio for training and testing. The model performance was evaluated using receiver operating characteristic curve analysis and sensitivity at a false positive rate of 10 %.

RESULTS

We included data of 4,394 women with singleton pregnancies, including 148 (3.4%) small for gestational age infants. Women delivering small for gestational age infants exhibited significantly shorter stature and lower fundal height and abdominal circumference at admission. Maternal height, age, and pre-pregnancy weight consistently ranked among the top 20 features in prediction models with any dataset. The models incorporated variables of admission stage have strong predictive performance with the area under the curves exceeding 0.8. The prediction model developed with variables of admission stage yielded the best performance, achieving an area under the curve of 0.85 and a sensitivity of 73% at the false positive rate of 10%.

CONCLUSIONS

By machine learning, various pregnancy stages' prediction models for small for gestational age showed good predictive performance, and the predictive value of variables at each pregnancy stage was fully explored. The prediction model with the best performance was established with variables of admission stage and emphasized the significance of prenatal physical examinations.

Ophthalmic artery Doppler in women with hypertensive disorders of pregnancy: relationship to blood pressure control and renal dysfunction at 6-9 weeks postnatally

OBJECTIVES

To examine the postnatal course of ophthalmic artery (OA) Doppler in women with hypertensive disorders of pregnancy (HDP) and to evaluate the correlation between OA Doppler parameters and poor postnatal blood pressure control and renal dysfunction at 2-3 weeks and 6-9 weeks postnatally.

METHODS

This was a prospective cohort study of women with a singleton pregnancy and HDP seen at a tertiary pregnancy hypertension clinic between 2019 and 2021. Three visits were included: Visit 1, the last visit to the antenatal hypertension clinic within 2 weeks prior to delivery; Visit 2, at 2-3 weeks postnatally; and Visit 3, at 6-9 weeks postnatally. At each visit, maternal demographic characteristics, medical history, blood pressure and OA Doppler were obtained. In addition, fetal growth and fetal Dopplers were examined antenatally and, at 6-9 weeks postnatally, estimated glomerular filtration rate and proteinuria were quantified. Study participants were divided into four hypertension groups, according to longitudinal changes in blood pressure at the three visits. For the postnatal visits, hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg and/or diastolic blood pressure (DBP) ≥ 90 mmHg in the absence of antihypertensive medication, and SBP ≥ 130 mmHg and/or DBP ≥ 80 mmHg whilst taking antihypertensives. Group 1 was hypertensive at all three visits; Group 2 was hypertensive at Visits 1 and 2 but normotensive at Visit 3; Group 3 was hypertensive at Visits 1 and 3 but normotensive at Visit 2; and Group 4 was hypertensive at Visit 1 but normotensive at Visits 2 and 3. The longitudinal changes in mean arterial pressure (MAP), peak systolic velocity (PSV) 1, PSV2 and the ratio of PSV2/PSV1 over the three timepoints were examined by a repeated-measures, multilevel, linear mixed-effects analysis, controlling for maternal age, weight at presentation and use of antihypertensive medication. In addition, we examined the longitudinal change in OA Doppler parameters in women with different degrees of postnatal blood pressure control and in those with and those without renal dysfunction at 6-9 weeks postnatally.

RESULTS

A total of 108 women were recruited to the study, of whom 86 had new-onset hypertension and 22 had chronic hypertension. When controlling for maternal age, weight at presentation and use of antihypertensive medication, a significant decline in log10 MAP (P < 0.001), log10 PSV1 (P < 0.001) and log10 PSV2 (P = 0.01) was seen between Visits 1 and 3. Log10 PSVR did not change with time. When assessing OA Doppler against hypertension group, log10 PSV1 and log10 PSV2 did not differ between the hypertension groups, whilst Group 4 had a lower log10 PSVR compared with Group 1 (P < 0.01), Group 2 (P = 0.03) and Group 3 (P < 0.01). At 6-9 weeks postnatally, log10 PSVR was lower in those without compared to those with renal dysfunction (-0.021, P = 0.01), whilst log10 MAP, log10 PSV1 and log10 PSV2 values did not differ. Log10 PSVR did not change with time and remained at -0.12 (95% CI, -0.13 to -0.11) across the three visits.

CONCLUSIONS

In women with HDP, the OA-PSVR was significantly higher in those with labile or persistently raised blood pressure postnatally compared to women whose blood pressure normalized. Similarly, the OA-PSVR at 6-9 weeks postnatally was significantly higher in women with renal dysfunction vs those without dysfunction. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Ophthalmic artery Doppler and biomarkers of impaired placentation at 36 weeks' gestation in pregnancies with small fetuses

OBJECTIVES

First, to compare ophthalmic artery peak systolic velocity (PSV) ratio and biomarkers of impaired placentation at 36 weeks' gestation in women who delivered a small-for-gestational-age (SGA) or growth-restricted (FGR) neonate, in the absence of hypertensive disorder, with those of women who developed pre-eclampsia (PE) or gestational hypertension (GH) and of women unaffected by SGA, FGR, PE or GH. Second, to examine the associations of PSV ratio, uterine artery pulsatility index (UtA-PI), placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) with birth-weight Z-score or percentile.

METHODS

This was a prospective observational study of women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, UtA-PI, PlGF and sFlt-1. Values of PSV ratio, UtA-PI, PlGF and sFlt-1 were converted to multiples of the median (MoM) or delta values. Median MoM or deltas of these biomarkers in the SGA, FGR, PE and GH groups were compared with those in the unaffected group. Regression analysis was used to examine the relationship of PSV ratio delta, UtA-PI MoM, PlGF MoM and sFlt-1 MoM with birth-weight Z-score, after exclusion of PE and GH cases.

RESULTS

The study population of 9033 pregnancies included 7696 (85.2%) that were not affected by FGR, SGA, PE or GH, 182 (2.0%) complicated by FGR in the absence of PE or GH, 698 (7.7%) with SGA in the absence of FGR, PE or GH, 236 (2.6%) with PE and 221 (2.4%) with GH. Compared with unaffected pregnancies, in the FGR and SGA groups, the PSV ratio delta and sFlt-1 MoM were increased and PlGF MoM was decreased; UtA-PI MoM was increased in the FGR group but not the SGA group. The magnitude of the changes in biomarker values relative to the unaffected group was smaller in the FGR and SGA groups than that in the PE and GH groups. In non-hypertensive pregnancies, there were significant inverse associations of PSV ratio delta and UtA-PI MoM with birth-weight Z-score, such that the values were increased in small babies and decreased in large babies. There was a quadratic relationship between PlGF MoM and birth-weight Z-score, with low PlGF levels in small babies and high PlGF levels in large babies. There was no significant association between sFlt-1 MoM and birth-weight Z-score.

CONCLUSIONS

Ophthalmic artery PSV ratio, reflective of peripheral vascular resistance, and UtA-PI, PlGF and sFlt-1, biomarkers of impaired placentation, are altered in pregnancies complicated by hypertensive disorder and, to a lesser extent, in non-hypertensive pregnancies delivering a SGA or FGR neonate. The associations between the biomarkers and birth-weight Z-score suggest the presence of a continuous physiological relationship between fetal size and peripheral vascular resistance and placentation, rather than a dichotomous relationship of high peripheral resistance and impaired placentation in small compared to non-small fetuses. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Ophthalmic artery Doppler at 19-23 weeks' gestation in pregnancies that deliver small-for-gestational-age neonates

OBJECTIVES

First, to explore hemodynamic differences between pregnancies delivering a small-for-gestational-age (SGA) neonate in the absence of hypertensive disorders and those that develop pre-eclampsia (PE) or gestational hypertension (GH), by comparing the ophthalmic artery peak systolic velocity (PSV) ratio and first (PSV1) and second (PSV2) PSV at 19-23 weeks' gestation, and second, to compare these pregnancies for markers of placental perfusion and function.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination for assessment of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, PSV1, PSV2, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and serum placental growth factor (PlGF). The values of PSV ratio, PSV1, PSV2, MAP, UtA-PI and PlGF were converted to multiples of the median (MoM) or deltas. Mean MoMs or deltas of these biomarkers in the SGA, PE and GH groups were compared with those in the unaffected group. The definition of SGA was birth weight below the 10^th percentile in the absence of PE or GH.

RESULTS

The study population of 5214 pregnancies contained 4375 (83.9%) that were unaffected by SGA, PE or GH, 563 (10.8%) complicated by SGA, 157 (3.0%) with PE and 119 (2.3%) with GH. There were three main findings of the study. First, in the SGA, PE and GH groups, compared with unaffected pregnancies, the PSV ratio delta, PSV2 MoM, MAP MoM and UtA-PI MoM were increased and PlGF MoM was decreased; however, the magnitude of most changes was smaller in the SGA group than in PE and GH groups. Second, in the PE and GH groups, but not in the SGA group, PSV1 MoM was increased. Third, in general, in the pathological pregnancies, the magnitude of deviation of biomarkers from unaffected pregnancies was greater for those delivering at < 37 than at ≥ 37 weeks' gestation.

CONCLUSION

In mid-gestation, pregnancies that subsequently develop hypertensive disorders and those delivering a SGA neonate, compared with unaffected pregnancies, have abnormal uteroplacental measurements and increased maternal ophthalmic artery PSV ratio. These data suggest similar pathophysiology in the two conditions, with evidence of placental dysfunction and increased peripheral vascular resistance, but the magnitude of abnormalities is greater in hypertensive disorders. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.