Reperfusion of the choriocapillaris observed using optical coherence tomography angiography in hypertensive choroidopathy

A CASE OF ELSCHNIG SPOTS OBSERVED USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY AFTER STENTING FOR INTERNAL CAROTID ARTERY DISSECTION

PURPOSE

We report the case of a 28-year-old man who developed Elschnig spots after stenting for an internal carotid artery dissection using optical coherence tomography angiography.

METHODS

This was a case report.

RESULTS

The patient developed a visual field defect in the left eye immediately after endovascular stenting for left internal carotid artery dissection. Fundus examination revealed white lesions and numerous mottled orange-red lesions in the posterior pole and midperiphery of the left eye. Indocyanine green angiography revealed mottled hypofluorescein areas in the early and late stages, coinciding with the orange-red lesions. Optical coherence tomography angiography showed flow void areas in the choriocapillaris layer, consistent with the orange-red lesions, which were diagnosed as Elschnig spots associated with choroidal circulatory failure. The spots disappeared approximately 2 months after surgery, and the flow void on optical coherence tomography angiography also disappeared.

CONCLUSION

We report a case of Elschnig spots associated with transient choroidal circulatory failure after stenting for internal carotid artery dissection. Optical coherence tomography angiography detected improved circulation at the level of the choriocapillaris with the disappearance of Elschnig spots.

Optical coherence tomography angiography assessment of retinochoroidal microcirculation differences in preeclampsia

BACKGROUND

To investigate microvascular changes in pregnant women with preeclampsia using optical coherence tomography angiography (OCTA) and compare the results with healthy pregnant and non-pregnant subjects.

METHODS

Superficial capillary plexus (SCP), deep capillary plexus (DCP) choriocapillaris (CC) vessel density (VD) and foveal avascular zone area (FAZ), retina, retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL) and the choroidal thickness were examined and compared in preeclamptic pregnant (group 1), healthy pregnant women (group 2) and non-pregnant, age-matched female controls (group 3). The correlations of the parameters with each other and with blood pressure were evaluated.

RESULTS

No significant difference was found between the groups when retinal, RNFL and GCL thickness values (p> 0.05). The choroidal thickness values were significantly lower in group 1 than in group 2 (p = 0.029). The central foveal VD of the SCP and DCP was significantly lower in group 1 compared to groups 2 and 3 (p = 0.03, p< 0.01 respectively). The mean VD of the SCP was significantly higher in groups 1 and 2 than in group 3 (p = 0.01). The FAZ area was statistically significantly lower in group 3 than in group 2 (p = 0.032). The CC VD was lower in group 3 compared to the other groups in all measurements (p < 0.01).The FAZ area was positively correlated with systolic blood pressure in group 1.

CONCLUSION

The use of OCTA, a non-invasive imaging technique, to assess the retinal microcirculation appears to have the potential to in the early diagnosis or follow up in preeclampsia before signs of hypertensive retinopathy.

Ocular microvascular alteration in patients with myocardial infarction-a new OCTA study

Myocardial infarction is defined as a sudden decrease or interruption in blood flow to the coronary arteries, causing ischemic necrosis of the corresponding cardiomyocytes. It is unclear whether systemic macrovascular alterations are associated with retinal microvascular changes. This study utilized optical coherence tomography angiography (OCTA) to compare variations in conjunctival vascular density and fundus retinal vessel density between patients with myocardial infarction (MI) and healthy controls. This study recruited 16 patients (32 eyes) with MI and 16 healthy controls (32 eyes). The superficial retinal layer (SRL), deep retinal layer (DRL) and conjunctival capillary plexus in each eye were evaluated by OCTA. Parameters measured included the density of the temporal conjunctival capillary, retinal microvascular (MIR) and macrovascular (MAR) alterations and total MIR (TMI). The microvascular density of each retinal region was evaluated by the hemisphere segmentation (SR, SL, IL, and IR), annular partition (C1, C2, C3, C4, C5 and C6), and modified early treatment of diabetic retinopathy study (R, S, L, and I) methods. In the macular area, the superficial and deep retinal microvascular densities displayed notable variations. In the superficial layers, the superficial TMI, superficial MIR, and superficial MAR, as well as densities in the SL, IL, S, L, C1, C2, C5 and C6 regions, were significantly lower in MI patients (p < 0.05 each). In the deep layers, the deep MIR and deep TMI), as well as densities in the SL, IL, L, C1, C2 and C6 regions were significantly lower in MI patients (p < 0.05 each). In contrast, the conjunctival microvascular density was significantly higher in MI patients than in healthy controls (p < 0.001). The microvascular densities measured in the deep and superficial retinal layers and in the conjunctiva differ in MI patients and healthy controls. OCTA is effective in detecting changes in the ocular microcirculation.

Unilateral hypertensive choroidopathy as a sole manifestation in malignant hypertension: optical coherence tomography angiography findings-case report

BACKGROUND

We present a case of hypertensive choroidopathy due to malignant hypertension with exudative retinal detachment as a sole finding. We use OCT- angiography for initial diagnosis and report findings from extensive follow up.

CASE PRESENTATION

A 51-year-old female with no past medical history, presented to our clinic with painless loss of vision in her left eye. Fundus examination revealed only exudative retinal detachment in her left eye that was confirmed with Optical Coherence Tomography. Fluorescein angiography showed hyperfluorescent spots with leakage in late phases. OCTA manifested a focal dark area in the choriocapillaris slab corresponding to flow signal voids, signifying regions of non-perfusion. Her blood pressure was 220/120 mmHG. Complete blood work -up failed to reveal any other possible etiology. During follow-up period of 9 months blood pressure normalized, patient regained visual function and choriocapillaris perfusion was completely restored.

DISCUSSIONS AND CONCLUSIONS

Hypertensive choroidopathy with exudative retinal detachment can be the only sign of malignant hypertension and no pre-existing history of a systemic disease is required in order to become apparent. OCTA reveals areas of non-perfusion at choriocapillaris level, proving that it is an essential tool in the diagnosis and follow up of patients with hypertensive choroidopathy. Finally, we propose that early diagnosis prevents permanent damage of the RPE and leads to complete choroidal remodeling and better visual outcomes.

UNILATERAL CHEMOSIS, BULLOUS SEROUS RETINAL DETACHMENT, AND PRESUMED BACILLARY LAYER DETACHMENT IN SEVERE PREECLAMPSIA

BACKGROUND/PURPOSE

To report a case of unilateral chemosis, serous retinal detachment (SRD), and presumed bacillary layer detachment in pregnancy.

METHODS

Clinical examination and multimodal imaging findings were reviewed and analyzed.

RESULTS

A 17-year-old female patient with severe preeclampsia was found to have unilateral chemosis and bullous SRD. Postpartum optical coherence tomography revealed thickened choroid and presumed bacillary layer detachment. Two weeks later, chemosis and SRD resolved, leaving behind mottled hyperpigmentation, drusen, and subretinal drusenoid deposits.

CONCLUSION

The combination of chemosis and SRD in preeclampsia is exceedingly, rare and it has never previously been reported to occur unilaterally. With delivery, visual acuity, chemosis, choroidal thickness, and SRD all normalize.

Diminished choroidal blood flow in hypertensive and preeclamptic third trimester pregnancies using optical coherence tomography angiography

PURPOSE

The aim of this study was to compare choroidal adjusted flow index (AFI) in healthy, hypertensive & preeclamptic pregnancies using optical coherence tomography angiography (OCTA).

METHODS

In this prospective study, healthy, hypertensive & preeclamptic third trimester pregnant women underwent OCTA imaging. 3x3 & 6x6 mm choriocapillaris slabs were exported and the parafoveal area was marked by two concentric ETDRS circles at 1 & 3 mm, centered on the foveal avascular zone. Parafoveal AFI was calculated as a parameter of choroidal blood flow.

RESULTS

Fifteen eyes of fifteen women per group were recruited (45 eyes). AFI was significantly lower in the preeclamptic compared to the healthy & hypertensive groups (Tukey HSD: <0.001 in both groups on 3x3 mm, and 0.02 & 0.04 in 6x6 mm scans), and in the hypertensive compared to the healthy group (0.005 & 0.03 in 3x3 & 6x6 mm scans respectively).

CONCLUSIONS

Pregnancies complicated with preeclampsia revealed the lowest choroidal blood flow on OCTA followed by pregnancies with systemic hypertension compared to healthy pregnancies. We provide in-vivo documentation of choroidal ischemia, highlighting its culpability in hypertensive and preeclamptic retinochoroidal pathology, and the possibility of utilizing choroidal blood flow on OCTA as a precursor for disease progression.

Hellp syndrome-related hypertensive chorioretinopathy: A multimodal imaging and optical coherence tomography angiography (OCTA) study

INTRODUCTION

Pregnancy may be associated to unique retinal disorders and is associated to worsening of retinal disease that also occurs in non-pregnant females. We report a case of chorioretinopathy caused by pre-eclampsia associated to HELLP (Hemolysis-Elevated-Liver enzymes and Low Platelet count) syndrome.

METHODS

Multimodal Imaging features of HELLP syndrome-related hypertensive chorioretinopathy including retinography, Spectral Domain-Optical Coherence Tomography (SD-OCT), Fluorescein angiography (FA), Indocyanine-green angiography (ICG) along with OCT-angiography (OCTA) are presented and discussed.

RESULTS

Multimodal imaging and OCTA show both retinal and choroidal involvement by HELLP syndrome, resolved after hypertension treatment.

CONCLUSIONS

Multimodal imaging is useful to study HELLP syndrome-related hypertensive chorioretinopathy. Moreover, OCTA is a new technology able to study and follow the circulatory status of the choriocapillaris during the disease.

Malignant Hypertension and the Role of Ophthalmologists: A Review Article

Malignant hypertension (MHT) is a sudden and severe increase in systemic blood pressure (BP) associated with advanced bilateral retinopathy. It comes under a broader term, called hypertensive emergency, where an acute rise in BP results in end-organ damage. The condition usually requires hospital admission and intensive care management. Although there are lots of sophisticated machines and laboratory tests present to diagnose various organ damage, the role of ophthalmologists will still be at the top. A record of the acute rise of BP to a defining level and simple ophthalmoscopy with high clinical suspicion can save a patient’s life and preserve target organ function by timely referral. So, every ophthalmologist should be aware of this dangerous condition. In this review, we have tried to compile all the current knowledge regarding malignant hypertension that an ophthalmologist may require in day-to-day practice.

Relationship between the sFlt-1/PlGF ratio and the optical coherence tomographic features of chorioretina in patients with preeclampsia

This study aimed to evaluate the correlation between ophthalmologic factors and the serologic indicator soluble fms-like tyrosine kinase 1 (sFlt-1): placental growth factor (PlGF) ratio in patients with preeclampsia using optical coherence tomography (OCT) and OCT angiography (OCT-A). A total of 52 pregnant patients (104 eyes) diagnosed with preeclampsia were recruited during their hospital stay. The associations between the sFlt-1/PlGF ratio and chorioretinal measurements, including the choroidal thickness (CT), foveal avascular zone, vascular density, and ganglion cell layer+ were evaluated. Central and nasal subfield CT of the left eye (p = 0.039; p = 0.010) and nasal subfield CT of the right eye (p = 0.042) were lower in the high sFlt-1/PlGF ratio group (≥38). Pearson’s correlation test showed a negative correlation between the sFlt-1/PlGF ratio and central subfield CT; however, this was not statistically significant (p = 0.648). Linear regression analysis revealed a significant association between the sFlt-1/PlGF ratio and central subfield CT (β coefficient, -6.66; p = 0.01) and between sFlt-1 and central subfield CT (β coefficient, -5.65; p = 0.00). Thus, an increase in the sFlt-1/PlGF ratio resulted in a decrease in central subfield CT.

Visualising the choriocapillaris: Histology, imaging modalities and clinical research - A review

The choriocapillaris plays a considerable role in the normal physiology of the eye as well as in various diseases. Assessing the changes in the choriocapillaris can therefore provide important information about normal ageing and pathogenesis of visual impairment, and even some systemic diseases. In vivo imaging of the choriocapillaris has evolved from non-depth resolved, dye-based angiography to advanced, high-resolution optical coherence tomography angiography (OCTA). However, the intricate microvascular networks within the choriocapillaris are still beyond the resolving limits of most OCTA instruments. Knowledge of histology, meticulous image acquisition methods, recognition of artefact and post-acquisition processing techniques are necessary for optimising OCTA choriocapillaris images. Qualitative and quantitative analyses of the choriocapillaris provide clinical information in age-related macular degeneration (AMD), diabetic retinopathy (DR), pathologic myopia and central serous chorioretinopathy (CSC). Furthermore, studies have revealed choriocapillaris changes in posterior uveitis that are correlated with treatment outcome and have important prognostic significance. In addition to retinal diseases, choriocapillaris changes have been observed in systemic vascular diseases and complications associated with pregnancy.

Choriocapillaris: Fundamentals and advancements

The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.

Chorioretinal Alterations Induced by Preeclampsia

Hypertension during pregnancy, which is essentially a microvascular disease that destroys the end-organ microcirculation, should not be underestimated, as it could lead to organ failure in the kidneys, lungs, and brain. Preassessment of the microcirculatory state through systematic observation of the fundus has been proven to be noninvasive and feasible. Although hypertension in preeclampsia patients will resolve after childbirth, the sticking point is determining the best termination moment. Early diagnosis and treatment can prevent long-term ocular complications and cardiovascular risks for pregnant women in the future. In order to adjust the treatment strategy through more sensitive and precise fundus changes, we comprehensively summarized the common structural changes in the fundus in preeclampsia patients, including changes in the blood vessels, choroid, and retina, as well as the application of quantitative observation for chorioretinal alterations in recent years.

Evaluation of the Choroid in Women with Uncomplicated Pregnancy

Purpose

To study the choroid in uncomplicated pregnant women using advanced optical coherence tomography (OCT) imaging and analysis.

Methods

Women with uncomplicated pregnancy in the third trimester (>28 weeks gestational age) and age-matched nonpregnant women were enrolled in this prospective study. All subjects underwent spectral-domain OCT with enhanced depth imaging mode and spectral-domain optical coherent tomography angiography (OCTA). Main outcomes were subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), and choriocapillaris flow deficits (CC FD).

Results

Twenty-two eyes of 12 uncomplicated pregnant women and 23 eyes of 15 nonpregnant, female controls were included. The mean age was 32.27 ± 6.96 years for the pregnant group and 30.08 ± 5.49 years for control group (P > 0.05). Mean SFCT was 238.70 ± 82.96 µm in the pregnant group, and 277.40 ± 61.79 µm in the control group. CVI was 67.58% ± 2.45% in the pregnant group and 67.31% ± 2.62% in the control group. The CC FD% was 54.06 ± 3.95 in the pregnant group, and 55.02 ± 3.78 in the control group. There was no significant difference between the pregnant and control groups (P > 0.05) in SFCT, CVI or CC FD.

Conclusions

Although extensive hemodynamic changes occurred with pregnancy, choroidal measurements by OCT and OCTA demonstrated no differences in uncomplicated third-trimester pregnant women compared with nonpregnant controls.

Translational Relevance

The unaltered choroid in uncomplicated third-trimester pregnancy we described allows clinicians to determine whether abnormal choroidal measurements could be used as a biomarker for complications of pregnancy.

A Review of Hypertensive Retinopathy and Chorioretinopathy

Hypertensive retinopathy and choroidopathy have important short- and long-term implications on patients' overall health and mortality. Eye care professionals should be familiar with the severity staging of these entities and be able to readily recognize and refer patients who are in need of systemic blood pressure control. This paper will review the diagnosis, staging, treatment, and long-term implications for vision and mortality of patients with hypertensive retinopathy and choroidopathy.

Optical coherence tomography angiography-derived flow density: a review of the influencing factors

Research interest in the possibility of quantifying macular and optic nerve head perfusion through optical coherence tomography angiography (OCTA) is rapidly advancing. Numerous scientific trials have furthered our understanding of the capabilities and the limitations of this novel technology, while applying OCTA to various ocular pathologies. In recent years, different parameters such as age, gender, intraocular pressure, spherical equivalent, physical activity, systemic diseases, and medication have been shown to have a significant impact on quantitative OCTA metrics. Since OCTA is likely to remain a "hot topic" in the near future, it is crucial to be aware of influencing factors in order to ensure correct interpretation of imaging results. This article reviews the factors currently known to influence flow density (FD) as measured by OCTA in healthy eyes.

Microvascular contributions to age-related macular degeneration (AMD): from mechanisms of choriocapillaris aging to novel interventions

Aging of the microcirculatory network plays a central role in the pathogenesis of a wide range of age-related diseases, from heart failure to Alzheimer's disease. In the eye, changes in the choroid and choroidal microcirculation (choriocapillaris) also occur with age, and these changes can play a critical role in the pathogenesis of age-related macular degeneration (AMD). In order to develop novel treatments for amelioration of choriocapillaris aging and prevention of AMD, it is essential to understand the cellular and functional changes that occur in the choroid and choriocapillaris during aging. In this review, recent advances in in vivo analysis of choroidal structure and function in AMD patients and patients at risk for AMD are discussed. The pathophysiological roles of fundamental cellular and molecular mechanisms of aging including oxidative stress, mitochondrial dysfunction, and impaired resistance to molecular stressors in the choriocapillaris are also considered in terms of their contribution to the pathogenesis of AMD. The pathogenic roles of cardiovascular risk factors that exacerbate microvascular aging processes, such as smoking, hypertension, and obesity as they relate to AMD and choroid and choriocapillaris changes in patients with these cardiovascular risk factors, are also discussed. Finally, future directions and opportunities to develop novel interventions to prevent/delay AMD by targeting fundamental cellular and molecular aging processes are presented.

Optical coherence tomography angiography findings in preeclampsia

OBJECTIVES

To investigate vascular density analysis in the superficial (SCP) and deep capillary plexus (DCP), foveal avascular zone (FAZ), peripapillary vascular density analysis (PPCVD), and peripapillary retinal nerve fiber thickness analysis (PPRNFL) using optical coherence tomography angiography (OCTA) in pregnant women with preeclampsia and to compare the obtained values with healthy pregnant and nonpregnant healthy individuals.

METHODS

A total of 98 pregnant women (55 had preeclampsia, 43 were healthy pregnant women) and 38 healthy nonpregnant women of reproductive age were included in the study. The patients were divided into three groups. Group 1 consisted of pregnant women with preeclampsia, group 2 comprised healthy pregnant women without preeclampsia, and group 3 consisted of healthy women who were not pregnant. All participants underwent a comprehensive ophthalmologic examination including OCTA.

RESULTS

Superficial foveal density (SFD) and deep foveal density (DFD) were lower in group 1 than in group 3 (p = 0.033, p = 0.041, respectively). Deep parafoveal density (DPD), deep temporal density (DTD), and deep superior density (DSD) values were lower in group 1 than in group 2 and group 3 (p = 0.001). PPRNFL superior and mean values were higher in group 1 and group 2 than in group 3 (p = 0.022, p = 0.029, respectively). The mean superior and inferior RPCVD values were significantly higher in group 1 than in group 2 and group 3 (p = 0.001, p = 0.043, and p = 0.001, respectively).

CONCLUSIONS

In preeclampsia, OCTA shows changes in the microvascular structure of the retina, even without retinopathy findings on biomicroscopy examination.

Age-dependent Changes in the Macular Choriocapillaris of Normal Eyes Imaged With Swept-Source Optical Coherence Tomography Angiography

PURPOSE

Swept-source optical coherence tomography angiography (SS-OCTA) was used to measure the age-dependent changes in macular choriocapillaris (CC) flow deficits (FDs) in normal eyes.

DESIGN

A prospective, cross-sectional study.

METHODS

Subjects with normal eyes ranging in age from their 20s to their 80s were imaged using a 100-kHz SS-OCTA instrument (PLEX Elite 9000, Carl Zeiss Meditec, Dublin, California, USA). Both 3 × 3-mm and 6 × 6-mm scans were used to image the macular CC. Visualization of the CC and quantification of FDs were performed using a previously validated algorithm. The percentage of FDs (FD%) in the central 1-mm circle (C₁), 1.5-mm rim (R_1.5), and 2.5-mm circle (C_2.5) from the 3 × 3-mm and 6 × 6-mm scans and FD% in the 2.5-mm rim (R_2.5) and 5-mm circle (C₅) from the 6 × 6-mm scans were measured and correlated with age and axial length.

RESULTS

A total of 164 subjects were enrolled, with at least 10 subjects from each decade of life. No meaningful correlations were found between FD% and axial length (|r| < 0.30). FD% in all fields increased with increasing age (all r > 0.50; all P < .001); however, the greatest increases were found in the central macula C₁ regions and the smallest increases in the peripheral macula R_2.5 regions.

CONCLUSIONS

In normal aging, the FD% increased with age across the central 5 mm of the macula, but the greatest increase was found in the central 1-mm region of the macula.