Evaluation of choroidal thickness and choroidal vascularity index during pregnancy

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.

Choroidal vascularity index in thyroid-associated ophthalmopathy

OBJECTIVE

To investigate the choroidal vascularity index (CVI) in patients with thyroid-associated ophthalmopathy (TAO) and its relationship with clinical features and clinical activity score METHODS: Right eyes of 53 patients with TAO and 53 healthy subjects were scanned for subfoveal choroidal thickness (SFCT), CVI, choroid-stromal area (C-SA), choroid-luminal area (C-LA), choroidal stromal index (CSI), choroid-stromal-to-luminal-area ratio, and CVI and CSI within the central 1500 µm of the macula (CVI₁₅₀₀ and CSI₁₅₀₀) by enhanced-depth imaging optical coherence tomography. The results of the TAO group and the healthy controls were compared.

RESULTS

The SFCT was significantly greater in the TAO group than in the control group (p = 0.02). The values of C-LA, C-SA, and total choroidal area (TCA) in the TAO group were significantly higher than those in the control group (p = 0.01, p = 0.04, and p = 0.01, respectively). The increases in SFCT, C-LA, C-SA, and TCA were 12.1%, 12.2%, 16.2%, and 13.6%, respectively. There was no statistically significant difference between the groups for CVI, CSI, CVI₁₅₀₀, CSI₁₅₀₀, and choroid-stromal-to-luminal-area ratio (p > 0.05). CVI₁₅₀₀ and CSI₁₅₀₀ have displayed a statistically significant correlation with exophthalmometry and clinical activity score (p < 0.05).

CONCLUSION

The alterations in stromal and vascular structures are proportionally similar in TAO; thus CVI may not be affected significantly. However, CVI₁₅₀₀ and CSI₁₅₀₀ may be associated with disease activity. The choroidal thickening in TAO may be the result not only of vascular mechanisms but also by an increase in stromal contents.