Assessment of the choroidal structure in pregnant women in the first trimester

Evaluation of choroidal thickness and retinal nerve fiber layer thickness in Chinese pregnant women and healthy non-pregnant women

Purpose

To evaluate choroidal thickness and retinal nerve fiber layer (RNFL) thickness in different trimesters using enhanced depth imaging optical coherence tomography (EDI-OCT).

Methods

A prospective comparative study included 45 healthy pregnant women in the first trimester, 45 women in the second, 45 women in the third and 45 healthy non-pregnant women as the control group. Macular choroidal thickness was measured at three locations: The subfoveal, 1 ​mm temporal, and 1 ​mm nasal from the fovea with EDI-OCT. Peripapillary choroidal thickness (PPCT) and RNFL thickness parameters were automatically calculated by the Spectralis OCT.

Results

The subfoveal, temporal and nasal macular choroidal thickness were all significantly thicker in the second trimester, compared with those parameters in the first, the third trimesters and the control group (all P ​< ​0.05). The PPCT was significantly increased in the second trimeter compared with the control group at global, temporal, temporal inferior, nasal and nasal inferior positions (all P ​< ​0.05). The RNFL thickness was also significantly increased in pregnant women at nasal superior and nasal inferior quadrants (all P ​< ​0.05).

Conclusions

The choroidal thickness in pregnant women was found to be thicker than the control group, regardless of macular or optic disc location. Findings of RNFL thickening might indicate subclinical involvement of the central nervous system.

Quantitative analysis of choroidal morphology in preeclampsia during pregnancy according to retinal change

We sought to investigate changes in choroidal hemodynamics in preeclampsia according to presence of retinal change by quantitatively assessing choroidal vessels using optical coherence tomography (OCT). This retrospective study included 106 eyes (of 53 patients) with preeclampsia, including 70 eyes without retinal change in patients with preeclampsia (Group A), 22 eyes with retinal change in patients with preeclampsia (Group B), and 14 eyes of normal pregnant women (controls). Subfoveal choroidal thickness (SFCT) was measured on OCT B-scan images, and choroidal vessel densities (CVDs) were calculated using binarized OCT B-scan and en face images. Their values were then correlated with clinical parameters associated with preeclampsia. SFCT was greater in Group B compared to Group A or controls (354.32 ± 65.13 vs. 288 ± 55.68 or 277.21 ± 50.08, both P < 0.001). CVD on B-scan images was greater in Group B compared to Group A or controls (76.4 ± 4.9 vs. 73.7 ± 5.3 or 71.5 ± 5.1; both P ≤ 0.046). CVD on en face images was also greater in Group B compared to Group A or controls (64.7 ± 0.8 vs. 63.6 ± 1.5 or 63.3 ± 1.3; both P ≤ 0.001). SFCT and CVD positively correlated with each other (P ≤ 0.009) and were greater in patients with blurred vision and vaginal bleeding (P ≤ 0.020 for blurred vision and P ≤ 0.024 for vaginal bleeding). SFCT and CVDs were higher in preeclampsia patients with retinal change compared to those without retinal change or controls. Both SFCT and CVD showed association with blurred vision and vaginal bleeding.

IMI-The Dynamic Choroid: New Insights, Challenges, and Potential Significance for Human Myopia

The choroid is the richly vascular layer of the eye located between the sclera and Bruch's membrane. Early studies in animals, as well as more recent studies in humans, have demonstrated that the choroid is a dynamic, multifunctional structure, with its thickness directly and indirectly subject to modulation by a variety of physiologic and visual stimuli. In this review, the anatomy and function of the choroid are summarized and links between the choroid, eye growth regulation, and myopia, as demonstrated in animal models, discussed. Methods for quantifying choroidal thickness in the human eye and associated challenges are described, the literature examining choroidal changes in response to various visual stimuli and refractive error-related differences are summarized, and the potential implications of the latter for myopia are considered. This review also allowed for the reexamination of the hypothesis that short-term changes in choroidal thickness induced by pharmacologic, optical, or environmental stimuli are predictive of future long-term changes in axial elongation, and the speculation that short-term choroidal thickening can be used as a biomarker of treatment efficacy for myopia control therapies, with the general conclusion that current evidence is not sufficient.

Changes in Choroidal Thickness and Structure in Preeclampsia with Serous Retinal Detachment

Preeclampsia is a pregnancy-specific syndrome characterized by hypertension and proteinuria. We retrospectively investigated the clinical features, including choroidal layer thickness and luminal area to stromal area ratio, in a case series of preeclampsia with serous retinal detachment (SRD). The subjects were pregnant women with SRD during hospitalization for preeclampsia from October 2014 to June 2021. Based on medical records, affected eyes, time of onset, fundus examination findings, and subfoveal choroidal thickness (SCT), the choroidal layer thickness and choroidal vascular index (CVI) in each patient was examined. Thirteen eyes from seven patients (mean age 30.7 ± 4.7 years) were included in the study. In all cases, SRD improved without topical ocular treatment. The mean SCT at the initial visit was 424.4 ± 70.5 μm, and all patients had choroidal thickening, which significantly decreased to 286.0 ± 57.9 μm (p < 0.01) at the last visit. The mean choroidal inner layer was 162.7 ± 69.4 μm at the initial visit and 122.3 ± 35.5 μm at the final follow-up visit (p = 0.06), showing no significant difference; however, the mean choroidal outer layer was 261.7 ± 47.6 μm at the initial visit and 163.7 ± 37.1 μm at the final follow-up visit (p < 0.01), thus showing a significant decrease. The mean CVI was 67.2 ± 1.3% at the initial visit, yet it had significantly decreased to 65.4 ± 1.1% (p < 0.01) at the final follow-up visit. The findings of this study show that SRD with preeclampsia is associated with increased thickening of the choroidal outer layer, especially in the choroidal luminal area.

Vascular Choroidal Alterations in Uncomplicated Third-Trimester Pregnancy

(1) Purpose: To evaluate the anatomy and perfusion of choroidal substructures in third-trimester pregnant women using optical coherence tomography (OCT) and OCT angiography (OCTA) imaging. (2) Methods: In this cross-sectional study, women in their third trimester of uncomplicated pregnancy and non-pregnant age-matched women were recruited. Participants underwent enhanced depth imaging (EDI) OCT and OCTA. Subfoveal choroidal thickness (SFCT), as well as choroidal sublayer perfusion, were compared between groups. (3) Results: In total, 26 eyes of 26 pregnant and 26 eyes of 26 non-pregnant women were included. The median age in both groups was 29 years. The median SFCT was 332 (211–469) µm in the pregnant group and 371.5 (224–466) µm in the non-pregnant cohort (p = 0.018). The median choriocapillaris perfusion (CCP) was significantly lower in the pregnant group (46% vs. 48%, p = 0.039). Moreover, Haller’s layer perfusion correlated significantly with mean arterial pressure in non-pregnant women (CC = 0.430, p = 0.028) but not in pregnant ones (CC = 0.054, p = 0.792). (4) Conclusions: SFCT was found to be thinner and CCP was lower in third-trimester pregnant women. Hormonal changes during pregnancy and consecutive impacts on autoregulation of small choroidal vessels might play an important role. Therefore, altered choroidal measurements during third-trimester pregnancy should be carefully evaluated as, to some extent, it could be a normal physiological change.

Association between serum soluble fms-like tyrosine kinase-1 and the central choroidal thickness during pregnancy: a prospective study

Objective

To investigate the association between serum soluble fms-like tyrosine kinase-1 (sFlt-1) and the choroidal structure during the pregnancy.

Methods and analysis

This prospective study enrolled 24 eyes of 12 consecutive healthy pregnant women. Each participant was evaluated during the first, second and third trimester of pregnancy and the postpartum period. The central choroidal thickness (CCT) and Choroidal Vascular Index (CVI) were measured using enhanced depth-imaging optical coherence tomography. Moreover, serum sFlt-1 and vascular endothelial growth factor (VEGF) concentrations were measured manually using ELISA. The association between choroidal structural parameters and serum sFlt-1/VEGF was analysed using a linear mixed model.

Results

The CCT was significantly thicker in the second and third trimester than the postpartum period (p<0.05). In contrast, there was no significant difference in the CVI throughout pregnancy or the postpartum period. Serum sFlt-1 levels were significantly higher during pregnancy than the postpartum period (p<0.05), whereas the serum VEGF levels were significantly lower during pregnancy than the postpartum period (p<0.05). Furthermore, serum sFlt-1 levels were significantly associated with CCT throughout pregnancy (p=0.011, linear mixed model). On the contrary, sFlt-1 levels was not associated with the CVI during the pregnancy.

Conclusion

Our results suggest that serum sFlt-1 might have an influence on the choroidal thickness during the pregnancy.