Mid-Phase Hyperfluorescent Plaques Seen on Indocyanine Green Angiography in Patients with Central Serous Chorioretinopathy

Polydopamine based photothermal/photodynamic synchronous coating modified intraocular lens for efficient and safer posterior capsule opacification prevention

Posterior capsule opacification (PCO), as one of the most common late complications after intraocular lens (IOL) implantation in cataract surgery, seriously affects patients' postoperative vision and surgical satisfaction, and can only be treated by laser incision of the posterior capsule. Although drug eluting coating modification have been proved to inhibit PCO effectively, the complicated coating methods and the potential toxicity of the antiproliferative drugs hinders its actual application. In this study, an indocyanine green (ICG) loaded polydopamine (PDA) coating modified IOL (IP-IOL) was designed to prevented PCO. In vitro and in vivo studies have shown that IP-IOL can effectively eliminate lens epithelial cells and significantly reduce the degree of PCO. At the same time, it still has good imaging quality and optical properties. Furthermore, both the near-infrared irradiation and ICG loaded PDA coating modified IOLs have proved to possess high biological safety to eyes. Thus, with easy preparation and safer near-infrared irradiated photothermal/photodynamic synchronous properties, such ICG loaded PDA coating provides an effective yet easier and safer PCO prevention after IOL implantation.

Value and Significance of Hypofluorescent Lesions Seen on Late-Phase Indocyanine Green Angiography

Background and Purpose

The hypofluorescence of fundus lesions observed during the late phase of indocyanine green angiography (ICGA) in various diseases has often been overlooked or misinterpreted. This article explores the significance of fundus lesions that are initially isofluorescent during the early phase of ICGA but become hypofluorescent later in the examination.

Findings

Pathologies such as multiple evanescent white spot syndrome, acute posterior placoid syphilitic chorioretinitis, chronic central serous chorioretinopathy, choroidal hemangioma, and some fundus with drusen, present this phenomenon of late hypofluorescence.

Interpretation

The interpretation of ICGA images and the role of indocyanine green (ICG) uptake by the retinal pigment epithelium (RPE) in late fundus fluorescence is debated. Experimental evidence suggests that ICG accumulates progressively in the RPE after intravenous injection of the dye or after direct contact in vitro, making it a potential marker of RPE activity. Although the exact mechanisms of ICG diffusion through the choroid and its binding to the RPE require further investigation, the late hypofluorescence observed in certain ICGA diseases provides information on different modalities of RPE dysfunction.

Financial Disclosures

The author has no proprietary or commercial interest in any materials discussed in this article.

Identification of Structures Labeled by Indocyanine Green in the Rat Choroid and Retina Can Guide Interpretation of Indocyanine Green Angiography

Purpose

Indocyanine green (ICG) is an albumin and lipoprotein binding dye absorbing in the far red used in angiography to visualize choroidal vessels (ICG angiography [ICGA]). To guide interpretation, ICG transport in the choroid, RPE, and retina of rats was studied.

Methods

Two conditions were used: RPE/choroid organoculture, incubated for 45 minutes in DMEM medium, 1% fetal bovine serum containing 0.25 mg/mL ICG and RPE/choroid and neural retina flat-mounts at 1 and 6 hours after intravenous ICG injection. Early and late sequences of ICGA were recorded until 6 hours. Ultra-deep red confocal microscope was used to localize ICG in flat-mounts and immunohistochemistry was performed for caveolin-1, tryptase (mast cell marker), and tubulin β3 (a nerve marker).

Results

In the organoculture, ICG penetrated homogeneously in the cytoplasm and stained the membranes of the RPE. At 1 hour after intravenous injection, ICG appeared in fine granules in RPE, partly labeled with caveolin-1 and decreasing at 6 hours. At 1 hour and 6 hours, ICG was found in the retinal vessels, faintly in the inner retina, and in the photoreceptor outer segments at 6 hours. In the choroid, ICG colocalized with mast cells, immunostained with tryptase, and accumulated along the large tubulin β3-labeled nerve bundles. The hypothesis was raised on the interpretation of late ICGA infrared photography in case of transthyretin amyloidosis with neuropathy.

Conclusions

Beside being a vascular dye, ICG is transported from the vessels to the RPE toward the outer retina. It stains mast cells and large choroidal nerves. These observations could help the analysis of ICGA images.

The choroidal nervous system: a link between mineralocorticoid receptor and pachychoroid

Central serous chorioretinopathy (CSCR) belongs to the pachychoroid spectrum, a pathological phenotype of the choroidal vasculature, in which blood flow is under the choroidal nervous system (ChNS) regulation. The pathogenesis of CSCR is multifactorial, with the most recognised risk factor being intake of glucocorticoids, which activate both the gluco- and the mineralocorticoid (MR) receptors. As MR over-activation is pathogenic in the retina and choroid, it could mediate the pathogenic effects of glucocorticoids in CSCR. But the role of MR signalling in pachychoroid is unknown and whether it affects the ChNS has not been explored. Using anatomo-neurochemical characterisation of the ChNS in rodents and humans, we discovered that beside innervation of arteries, choroidal veins and choriocapillaris are also innervated, suggesting that the entire choroidal vasculature is under neural control. The numerous synapses together with calcitonin gene-related peptide (CGRP) vesicles juxtaposed to choroidal macrophages indicate a neuro-immune crosstalk. Using ultrastructural approaches, we show that transgenic mice overexpressing human MR, display a pachychoroid-like phenotype, with signs of choroidal neuropathy including myelin abnormalities, accumulation and enlargement of mitochondria and nerves vacuolization. Transcriptomic analysis of the RPE/choroid complex in the transgenic mice reveals regulation of corticoids target genes, known to intervene in nerve pathophysiology, such as Lcn2, rdas1/dexras1, S100a8 and S100a9, rabphilin 3a (Rph3a), secretogranin (Scg2) and Kinesin Family Member 5A (Kif5a). Genes belonging to pathways related to vasculature development, hypoxia, epithelial cell apoptosis, epithelial mesenchymal transition, and inflammation, support the pachychoroid phenotype and highlight downstream molecular targets. Hypotheses on the imaging phenotype of pachychoroid in humans are put forward in the light of these new data. Our results provide evidence that MR overactivation causes a choroidal neuropathy that could explain the pachychoroid phenotype found in transgenic mice overexpressing human MR. In patients with pachychoroid and CSCR in which systemic dysautonomia has been demonstrated, MR-induced choroidal neuropathy could be the missing link between corticoids and pachychoroid.

[Central serous chorioretinopathy: A review]

The central serous chorioretinopathy (CSCR) is characterized by serous retinal detachments SRD associated with one or several retinal pigment epithelium detachments/irregularities (PEDs). The choroid is thickened with dilated choroidal veins and choroidal hyperpermeability suggesting an underlying choroidopathy. CSCR belongs to the pachychoroid spectrum. CSCR affects mostly middle-aged men and the main risk factor is the corticosteroid intake. In most cases, the subretinal detachment resolves spontaneously with a good visual prognosis. However, recurrent or chronic form of the disease can lead to irreversible retinal damage and decreased visual acuity. Laser on an extra foveal leak point or half dose/half fluence photodynamic therapy are the first-line treatment options.

INDOCYANINE GREEN ANGIOGRAPHY OF TYPE 1 MACULAR NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION AND CENTRAL SEROUS CHORIORETINOPATHY REVEALS DIFFERENT DISEASE MECHANISMS

PURPOSE

To assess the rate of late phase hyperfluorescent plaque (LPHP) in Type 1 macular neovascularization (MNV) in central serous chorioretinopathy (CSCR) and age-related macular degeneration (AMD) and to evaluate its prognostic value.

METHODS

Retrospective study including Type 1 MNV in AMD and CSCR, from 2012 to 2020. Eyes with a late indocyanine green angiography image (>20 minutes) and clear visualization of MNV on optical coherence tomography angiography (OCTA) were included. Quantitative and qualitative parameters on optical coherence tomography and best-corrected visual acuity were recorded at baseline and after three monthly antivascular endothelial growth factor injections.

RESULTS

Eighty-three eyes were included, 35 with CSCR and 48 with AMD. Patients in the CSCR group were significantly younger than in the AMD group (61.3 ± 10.4 vs. 80.2 ± 6.8 years, respectively, P < 0.001), predominantly male (68.6% CSCR vs. 35.4% AMD; P = 0.003), and with a thicker choroid (379 ± 93.3 µ m vs. 204.2 ± 93.2 µ m; P < 0.001). Type 1 MNV in CSCR showed fewer LPHP compared with AMD (31.4% vs. 77.1%; P < 0.001). The baseline visual acuity was lower in patients with LPHP (0.37 ± 0.22 vs. 0.27 ± 0.28 logarithm of the minimum angle of resolution, P = 0.03). On multivariate analysis, AMD was associated with the presence of LPHP ( P < 0.001). No significant difference in the response to antivascular endothelial growth factor was observed.

CONCLUSION

Leakage of macromolecules from MNV and accumulation in the retinal pigment epithelium and/or in the stroma imaged by the LPHP is less common in eyes with Type 1 MNV in CSCR than in AMD. Late phase indocyanine green angiography imaging offers an insight into the metabolism of the dye and the environment surrounding the neovascular membrane.

Ten-year follow-up and sequential evaluation of multifocal retinal pigment epithelium abnormalities in central serous chorioretinopathy

PURPOSE

The study aims to analyze the 10-year outcomes in "simple" and "complex" central serous chorioretinopathy (CSCR) and to evaluate the longitudinal changes in multifocal retinal pigment epithelium (RPE) alterations.

METHODS

This was a retrospective, multicentric, longitudinal, observational study in patients with a diagnosis of CSCR. Visual acuity outcomes and recurrence characteristics of simple and complex were analyzed. Changes in number of foci of RPE alterations from baseline to last visit were evaluated.

RESULTS

Out of 235 eyes screened, the study included 67 eyes of 39 patients (32 males and 7 females) with CSCR (12 simple and 55 complex CSCR). A total of 17 (29.9%) eyes had a unifocal RPE alteration, while the remaining 50 had multifocal RPE alterations at baseline. In eyes with complex CSCR, the 10-year visual acuity was significantly worse (p < 0.001), more number of eyes required treatment (p = 0.03), higher number of RPE alterations were present at baseline and last follow-up (p < 0.001 for both), and number of recurrences were higher (p < 0.001), than simple CSCR. Focal collections of RPE alterations and leakage site corresponded to mid-phase hyper-fluorescent plaques (MPHP) in all eyes. On multivariate regression analysis, a larger area of RPE alteration was associated with a worser 10-year visual acuity (p = 0.004) and complex CSCR was associated with higher number of recurrence (p = 0.005).

CONCLUSION

A different course of disease progression was seen in simple and complex CSCR. An evolution in foci of RPE alterations was seen, from a simple area of MPHP, to focal RPE alterations and finally to leakage.

Morphometric analyses in patients treated with subthreshold laser photocoagulation for central serous chorioretinopathy

BACKGROUND AND OBJECTIVE

To analyze changes in selected parameters in optical coherence tomography (OCT) after subthreshold laser coagulation (ST-LP) in patients with central serous chorioretinopathy (CSCR).

MATERIALS AND METHODS

Fifty-four eyes of 49 patients with CSCR were included in the study. Each patient underwent therapy with ST-LP with a frequency-doubled Neodym-YAG Laser and OCT imaging. In OCT the thickness of the central subfield, cube volume, average cube thickness, volume under the ETDRS grid, and average thickness under the ETDRS grid were collected.

RESULTS

Decreases in total OCT volume and central retinal subfield thickness were statistically significant (p < 0.05). Possible correlations were observed between visual acuity at V3 (3 months after ST-LP) and Baseline and between central retinal subfield thickness at V1 (4 weeks after ST-LP) and visual acuity at BL.

CONCLUSION

A decrease in retinal thickness and retinal volume could be shown after ST-LP. Central retinal subfield thickness measured by OCT could be a more sensitive measure than mean retinal thickness or macular volume for early detection of disease recurrence occurring in some patients 3 months after ST-LP.

Modified low-dose second window indocyanine green technique improves near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection: A randomized control trial

Objective

Conventional second window indocyanine green (SWIG) technique has been widely attempted in near-infrared fluorescence (NIRF) imaging for intraoperative navigation of tumor radical resection. Nevertheless, the overuse of indocyanine green (ICG) led to an increased risk of drug lethal allergy and high medical cost. This prospective study was to explore clinical application of modified low-dose SWIG technique in guiding dermatofibrosarcoma protuberans (DFSPs) radical resection.

Method

Patients with DFSPs were randomly assigned to control and experimental group. The ICG was injected intravenously 24 h before surgery, at a dose of 3.5 mg/kg in the control group and 25 mg/patient in the experiment group, respectively. Intraoperative NIRF imaging included serial views of gross tumor, tumor bed and cross-sectional specimen.

Results

Although NIRF imaging of gross tumor and tumor bed in the experimental group demonstrated similar sensitivity and negative predictive value, the specificity and positive predictive value were obviously higher compared to control group. The tumor-to-background ratios of cross-sectional specimens in the experimental group was significantly higher than in the control group (P = 0.000). Data in both groups displayed that there was a positive correlation of tumor size in cross-sections between integrated histopathologic photomicrographs and NIRF imaging of specimen views (P = 0.000). NIRF imaging of cross-sectional specimens had a significant decrease in time cost, and an increase in the ability of examining more surgical margins (P = 0.000).

Conclusion

This is the first study to demonstrate that a low-dose SWIG technique could improve the accuracy of near-infrared fluorescence image-guided dermatofibrosarcoma protuberans resection.

Clinical Trial Registration: ChiCTR2100050174; date of registration: August 18, 2021 followed by “retrospectively registered”

Clinical Characteristics and Multimodal Imaging Findings of Central Serous Chorioretinopathy in Women versus Men

(1) The aim of this study was to compare the clinical characteristics and multimodal imaging findings of central serous chorioretinopathy (CSCR) between women and men. (2) Women and men with CSCR were compared in terms of their age and risk factors, the clinical form of their disease, multimodal imaging findings and the presence of macular neovascularization (MNV) on optical coherence tomography (OCT)-angiography. (3) Results: The data of 75 women and 75 men were compared. The women were significantly older than the men (52.2 years versus 45.7 years; p < 0.001). Corticosteroid intake was more frequent in the women (56% versus 40%; p = 0.05). The women had a single foveal subretinal detachment more often than the men (73.3% versus 46.9%; p < 0.001) and they often had fewer gravitational tracks (16.3% versus 29.6%; p = 0.03). On mid-phase indocyanine green angiography, hyperfluorescent plaques were detected less often in the women than in the men (48% versus 72.2%, p = 0.001). MNV was detected on OCT-angiography in 35.9% of the women and in 13.3% of the men (p = 0.004). (4) In the women, CSCR occurs at an older age, is more often unifocal foveolar, and is associated with a higher rate of MNV. The reasons for these gender-related differences remain to be determined.

OCT Angiography Fractal Analysis of Choroidal Neovessels Secondary to Central Serous Chorioretinopathy, in a Caucasian Cohort

Central serous chorioretinopathy (CSCR) can be complicated by different types of choroidal neovascularization (CNV). The purpose of this study was to investigate the incidence and quantitative optical coherence tomography angiography (OCT-A) features of CSCR-related CNVs. Methods: This was a retrospective multicenter study including 102 eyes of 102 Caucasian patients with acute or complex CSCR. All patients underwent a comprehensive ophthalmological examination. Quantitative OCT-A parameters, including vascular perfusion density (VPD), fractal dimension (FD), and lacunarity (LAC), were measured in CNV eyes. Results: Forty eyes (39.2%) had acute CSCR, whereas the remaining sixty-two (60.8%) had complex CSCR. CNV was observed in 37 (36.27%) eyes, all of which had the complex form. CNVs were classified as type 1 CNV in 11/37 (29.73%) cases and as polypoidal choroidal vasculopathy (PCV) in the remaining 26/37 (70.27%). Overall, the mean VPD, FD, and LAC of CSCR-related CNVs were 0.52 ± 0.20%, 1.44 ± 0.12, and 2.40 ± 1.1, respectively. No significant difference between type 1 CNV and PCV was found. Conclusion: Complex CSCR is often complicated by type 1 CNV and PCV with similar neovascular architecture and branching complexity, a finding supporting the idea that they might be different stages of the same neovascular process. Future OCT-A fractal analysis-based studies that also include other relevant parameters, such as demographics, presentation, morphology on multimodal imaging, and response to treatment, are necessary before drawing any definitive conclusions.