Choroid Of Eye Research Articles

OCT Angiography of the Retina and the Choroid in the Macula in Patients with Normal Tension Glaucoma and Primary Open Angle Glaucoma.

The aim of this study was to compare vessel density (VD) in the retina and choroid in eyes with primary open angle glaucoma (POAG), normal tension glaucoma (NTG) and controls. Patients with POAG, NTG and controls underwent OCT scanning of the macula and the disc followed by 6 × 6 mm macula OCT angiography (OCTA) imaging. Global and hemifield VD were recorded for the superficial (SVP) and deep (DVP) vascular plexus and the choriocapillaris (CC). The OCT thickness of the nerve fiber layer (NFL) and ganglion cell layer (GCC) was also measured. Data from 65 POAG, 33 NTG and 40 control eyes matched for age were analyzed. Mean SVP VD was lower in NTG and POAG eyes compared to controls (38.8 ± 5.3, 40.7 ± 6.8 and 48.5 ± 4.0%, p < 0.001). Mean DVP VD was lower in NTG and POAG eyes compared to controls (43.1 ± 6.1, 44.5 ± 7.6 and 48.6 ± 5.8%, p = 0.002). There was no difference in SVP VD or DVP VD between the glaucoma groups (p > 0.050). No difference was noted in CC VD between the groups (68.3 ± 2.3, 67.6 ± 3.7 and 68.5 ± 2.6%, p = 0.287). Lower SVP and DVP VD was seen in eyes with glaucoma compared to normal eyes. NTG and POAG eyes had similar VD loss. Eyes with glaucoma manifested similar CC VD compared to controls.

Integrity of the Hyperreflective Layer in the Inner Choroid in Eyes with Drusen.

This study aimed to compare the integrity of the hyperreflective layer of the inner choroid in eyes with and without drusen. Swept-source optical coherence tomography images of patients with drusen and normal controls were reviewed. Using a line plot of ImageJ, choroidal reflectivity was measured at the subfovea, and the integrity of the hyperreflective layer of the inner choroid was determined. In total, 63 eyes with drusen and 30 control eyes without drusen were included. The integrity of the hyperreflective layer of the inner choroid was preserved in 81.0% of eyes with drusen and 93.3% of normal controls. The proportion of eyes with the hyperreflective layer did not differ between eyes with and without drusen. Of the 63 subjects with drusen, this hyperreflective layer was observed in all 28 eyes (100%) with pachydrusen but only in 68.6% of the 35 eyes with soft drusen, and its prevalence was significantly different (P = 0.001). The prevalence of the hyperreflective layer between the choriocapillaris and medium or large choroidal vessels in eyes with soft drusen differed from that in eyes with pachydrusen. These findings support the suggestion that changes within the choroidal stroma may be involved in the pathogenesis of age-related macular degeneration.

Long-term choroidal thickness changes based on the subtype of macular neovascularization in neovascular age-related macular degeneration (5-year follow-up).

To evaluate the long-term choroidal thickness changes in combination with other morphological and functional outcomes during anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (nAMD) based on the subtype of macular neovascularization (MNV): MNV-1 (within the subretinal pigment epithelium space) and MNV-2 (within the subretinal space). This retrospective study included 58 eyes from 53 patients with naïve nAMD who received anti-VEGF therapy over a 60-month period. All eyes were treated initially with intravitreal bevacizumab following Pro re nata regimen. Main outcome measures included the following: subfoveal choroidal thickness (SFCT), best corrected visual acuity (BCVA), central macular thickness (CMT), development of subfoveal geographic atrophy (GA), and the number of injections. Thirty-four eyes had MNV-1 (group 1) and 24 eyes had MNV-2 (group 2). SFCT in group 1 vs group 2 was (210 ± 45µm vs 191 ± 52µm, p = 0.01) before treatment and (170 ± 47µm vs 179 ± 48µm, p = 0.24) after 60months. BCVA (log MAR) in group 1 vs group 2 was (0.57 ± 0.18 vs 0.53 ± 0.22, p = 0.47) before treatment and (0.59 ± 0.23 vs 0.69 ± 0.16, p = 0.04) after 60months. CMT in group 1 vs group 2 was (398 ± 154µm vs 382 ± 103µm, p = 0.86) before treatment and (297 ± 68µm vs 283 ± 67µm, p = 0.14) after 60months. The number of injections per eye over a period of 60months was significantly higher in group 1 (34.9 ± 11 vs 29.0 ± 14, p = 0.04). The proportion of eyes with subfoveal GA after 60months was significantly higher in group 2 (13 eyes, 54%) than in group 1 (9 eyes, 25%) (p = 0.03). Over the full 60months of anti-VEGF treatment, eyes with MNV-1 showed a greater reduction in choroidal thickness, better visual acuity, and less development of subfoveal geographic atrophy compared with eyes with MNV-2. The significantly thicker choroid in eyes with MNV type 1 at baseline seems to have a positive impact on long-term outcomes.

Single-shot OCT and OCT angiography for slab-specific detection of diabetic retinopathy.

In this study, we present an optical coherence tomographic angiography (OCTA) prototype using a 500 kHz high-speed swept-source laser. This system can generate a 75-degree field of view with a 10.4 µm lateral resolution with a single acquisition. With this prototype we acquired detailed, wide-field, and plexus-specific images throughout the retina and choroid in eyes with diabetic retinopathy, detecting early retinal neovascularization and locating pathology within specific retinal slabs. Our device could also visualize choroidal flow and identify signs of key biomarkers in diabetic retinopathy.

Association of Retinal Pigment Epithelium Reflectivity on Optical Coherence Tomography with Recurrence of Vogt-Koyanagi-Harada Disease: A Retrospective Observational Study.

Despite the necessity of optical coherence tomography (OCT) for diagnosis and longitudinal monitoring in patients with Vogt-Koyanagi-Harada (VKH) disease, no studies have identified useful OCT markers for predicting recurrence in these patients. Although the precise reason for this remains unclear, one possibility is that infiltration of inflammatory cells into the choroid attenuates the OCT signal, making it difficult to precisely assess the structure of the choroid. Therefore, this study aimed to investigate changes in retinal pigment epithelium (RPE) reflectivity immediately above the choroid in eyes with acute VKH disease, as well as the association between RPE reflectivity and VKH disease recurrence. This single-centered retrospective observational study included 20 treatment-naïve patients with acute VKH disease presenting with serous retinal detachment (SRD) in the posterior pole at the initial visit between October 2015 and January 2020, as well as 15 healthy control eyes. All patients were followed up for at least 6 months and received treatment with intravenous methylprednisolone followed by oral administration of prednisolone. Swept-source OCT images through the fovea were used to measure central retinal thickness, central choroidal thickness, and RPE reflectivity. During an observation period of 37.2 ± 30.8 months, recurrence of inflammation was observed in 11 patients (55.0%). Initial visual acuity was worse in patients who developed recurrence than in those who did not (P=0.024). On initial OCT images, RPE reflectivity differed significantly between patients with and without recurrence (1.75 ± 0.42 vs 1.35 ± 0.20; P=0.018), while there were no significant differences in other chorioretinal parameters, such as central retinal thickness and choroidal thickness. RPE reflectivity on OCT images may be useful for predicting the recurrence of inflammation in patients with VKH disease.

Discrepancy between peripapillary retinal and choroidal microvasculature and the rate of localized retinal nerve fiber layer thinning in glaucoma

This observational case series study is conducted to compare the extent of microvasculature impairment in the peripapillary retina and choroid in eyes with primary open-angle glaucoma (POAG), and to investigate the association of the discrepancy between the microvasculature impairments of each layer with the rate of progressive retinal nerve fiber layer (RNFL) thinning. A total of 88 POAG eyes with a localized RNFL defect were enrolled, including 67 eyes with and 21 eyes without choroidal microvasculature dropout (CMvD). Circumferential widths of retinal microvascular impairment (RMvI) and CMvD were measured, and eyes were classified based on the relative width of CMvD to RMvI (CMvD/RMvI ratio). The rate of RNFL thinning was determined by linear regression based on ≥ 5 serial OCT examinations. Thinner global RNFL and worse visual field mean deviation at baseline were associated with a larger circumferential width of the RMvI, whereas the presence of cold extremities, lower mean arterial pressure and thinner juxtapapillary choroid were associated with a larger circumferential width of the CMvD. The rate of global RNFL thinning was faster in eyes with larger relative CMvD width than in eyes with equal CMvD and RMvI widths and in eyes without CMvD (P = 0.001). Lower mean arterial pressure (P = 0.041), larger CMvD width (P = 0.046), larger CMvD/RMvI ratio (P = 0.041), and detection of disc hemorrhage during the follow-up (P = 0.013) were significant factors associated with faster global RNFL thinning. Larger CMvD width relative to RMvI width may be indicative of an increased risk of faster RNFL thinning in POAG with localized RNFL defect. Comparing the microvasculature impairment in individual layers may help predict more rapid glaucoma progression.

Microbubble-Assisted Ultrasound for Drug Delivery to the Retina in an Ex Vivo Eye Model.

Drug delivery to the retina is one of the major challenges in ophthalmology due to the biological barriers that protect it from harmful substances in the body. Despite the advancement in ocular therapeutics, there are many unmet needs for the treatment of retinal diseases. Ultrasound combined with microbubbles (USMB) was proposed as a minimally invasive method for improving delivery of drugs in the retina from the blood circulation. This study aimed to investigate the applicability of USMB for the delivery of model drugs (molecular weight varying from 600 Da to 20 kDa) in the retina of ex vivo porcine eyes. A clinical ultrasound system, in combination with microbubbles approved for clinical ultrasound imaging, was used for the treatment. Intracellular accumulation of model drugs was observed in the cells lining blood vessels in the retina and choroid of eyes treated with USMB but not in eyes that received ultrasound only. Specifically, 25.6 ± 2.9% of cells had intracellular uptake at mechanical index (MI) 0.2 and 34.5 ± 6.0% at MI 0.4. Histological examination of retinal and choroid tissues revealed that at these USMB conditions, no irreversible alterations were induced at the USMB conditions used. These results indicate that USMB can be used as a minimally invasive targeted means to induce intracellular accumulation of drugs for the treatment of retinal diseases.

Comparison of Chorioretinal Parameters in Diabetic Retinopathy with or without Pan-Retinal Photocoagulation Using Ultrawide-Field Swept-Source Optical Coherence Tomography Angiography

Introduction: To compare structural and vascular parameters in the central and peripheral retina and choroid of eyes diagnosed with severe nonproliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) with or without pan-retinal photocoagulation (PRP) using ultrawide-field swept-source optical coherence tomography angiography (SS-OCTA). Methods: All participants underwent SS-OCTA imaging centered on the fovea. Retinal and choroidal thickness, vessel density of the superficial capillary plexus (SCP), deep capillary plexus (DCP), choroidal capillary plexus (CCP), and choroidal Sattler’s and Haller’s layer (CSHL) were analyzed in nine grids using built-in angiography analysis software. Results: A total of 82 eyes from 82 participants were enrolled in this study, including 40 eyes diagnosed with severe NPDR or PDR without PRP and 42 eyes with PRP. Retinal thickness in part grids was higher in eyes with PRP than in eyes without PRP. Vessel density of the SCP in nasal-superior (p = 0.003) grid was lower in eyes with PRP than in eyes without PRP. No significant difference was found in the vessel density of the DCP between the two groups (all p > 0.05). The choroidal thickness and vessel density of the CSHL of all grids were significantly lower in eyes with PRP than in eyes without PRP (all p < 0.05). A statistically significant decrease in vessel density in CCP was found in the superior (p = 0.043), nasal-superior grid (p = 0.003), macular grid (p < 0.001), and optic disc grid (p = 0.001) of eyes with PRP, compared to eyes without PRP. A significant decrease in the vessel density of CSHL was observed in all grids of PDR eyes with PRP compared to PDR eyes without PRP (all p < 0.05). Significant decrease in choroidal thickness was observed in most grids of PDR eyes with PRP, except for macular grid (p = 0.090) and optic disc grid (p = 0.057). Conclusion: Structural and vascular parameters in the central and peripheral retinal and choroidal layers in eyes diagnosed with severe NPDR or PDR with or without PRP could be quantified using a ultrawide-field SS-OCTA. Eyes with PRP showed a significant decrease in choroidal thickness and vessel density of CCP and CSHL, compared with eyes without PRP. This trend was more obvious in eyes with PDR.

Choroidal thickness in exudative age‐related macular degeneration and influence of intravitreal anti‐VEGF treatment

AbstractPurpose: To evaluate choroidal thickness progression over time in patients with exudative age‐related macular degeneration (AMD) and its relation with anti‐VEGF treatment.Methods: Retrospective observational case series. Study group included patients observed between January 2022 and April 2022 at Ophthalmology Department of Hospital de São João, Porto, Portugal, diagnosed with bilateral exudative AMD (eAMD) or unilateral eAMD and intermediate AMD (iAMD) in contralateral eye with a minimum follow up of 2 years. Subfoveal choroidal thickness was measured in each of the studied eyes using cross‐sectional spectral domain optical coherence tomography images, obtained every year during follow‐up period. Statistical analysis was performed to correlate choroidal thickness variation with number of intravitreal injections.Results: 66 eyes with eAMD and 20 eyes with iAMD from 43 patients (mean age, 81.15 ± 6.10 years) followed during 7.15 ± 2.65 years. eAMD eyes were treated with 54.83 (range 6–100 injections) anti‐VEGF intravitreal injections. Choroidal thickness of eyes with eAMD decreased 56.65 ± 11.66 μm over the follow up period (p &lt; 0.001) at a rate of 6.49 μm per year. Choroidal thickness of eyes with iAMD decreased 29.30 ± 22.07 μm over the follow up period (p &gt; 0.2) at a slower rate of 0.68 μm per year. In the subgroup of patients with unilateral eAMD and contralateral iAMD (n = 20), choroidal thickness changes were significantly different between the two eyes (p &lt; 0.001). Number of intravitreal injections correlated inversely with choroidal thickness in eyes with eAMD (r = −0.232; p &lt; 0.001).Conclusions: A significant thinning of choroid in eyes with eAMD and an inverse correlation with number of anti‐VEGF injections was observed, suggesting the influence of prolonged anti‐VEGF suppression on choroidal thickness decrease. Further studies with a higher number of eyes are needed to validate our results.

Retinal Pigment Epithelium-Secreted VEGF-A Induces Alpha-2-Macroglobulin Expression in Endothelial Cells.

Alpha-2-macroglobulin (A2M) is a protease inhibitor that regulates extracellular matrix (ECM) stability and turnover. Here, we show that A2M is expressed by endothelial cells (ECs) from human eye choroid. We demonstrate that retinal pigment epithelium (RPE)-conditioned medium induces A2M expression specifically in ECs. Experiments using chemical inhibitors, blocking antibodies, and recombinant proteins revealed a key role of VEGF-A in RPE-mediated A2M induction in ECs. Furthermore, incubation of ECs with RPE-conditioned medium reduces matrix metalloproteinase-2 gelatinase activity of culture supernatants, which is partially restored after A2M knockdown in ECs. We propose that dysfunctional RPE or choroidal blood vessels, as observed in retinal diseases such as age-related macular degeneration, may disrupt the crosstalk mechanism we describe here leading to alterations in the homeostasis of choroidal ECM, Bruch’s membrane and visual function.

Thickness of the choroid, ciliary body and retina according to optical coherence tomography in patients after Femto LASIK

Background. In the available literature, there are isolated publications devoted to the topic of the possible effect of laser correction by the Femto LASIK method on the myopic eye choroid. In this connection, in our opinion, the relevance of continuing research in this direction remains.The aim of this study was to examine the volume of the retina in the macular zone, the thickness of the choroid and the ciliary body using optical coherence tomography on myopic eyes after femtosecond-assisted laser in situ keratomileusis in the short term.Material and methods. 30 patients (30 right eyes) aged 20 to 35 years, suffering from mild and moderate myopia, but without pathological changes in the retina according to OCT, made up the study group. All patients underwent myopia correction using the Femto LASIK method. Before the operation, after 4 hours and the next day, they underwent the examination of the retinal volume in the macular zone, the choroidal and the ciliary body thickness using OCTResults. The analysis of the obtained results of the studied parameters showed that the ciliary body thickness and the retinal volume in the macular zone did not undergo statistically signifi cant changes and remained within the preoperative values (p &gt; 0.05). We observed a tendency to an increase in the thickness of the choroid 4 hours after the operation, but the carried out statistical analysis did not confi rm the reliability of its changes (p &gt; 0.05). On the next day, the choroidal thickness indices practically recovered to the preoperative level (p &gt; 0.05).Conclusion. A study of the retinal volume in the macular zone, the thickness of the choroid and ciliary body using OCT in myopic eyes in the short term after Femto LASIK showed the absence of statistically signifi cant changes in the studied parameters, which indirectly indicates the safety of this method of laser correction for the posterior segment of the eye.

Hyperreflective foci in the choroid of normal eyes.

To investigate hyperreflective choroidal foci (HCF) using en face swept-source optical coherence tomography (SS-OCT) and determine the factors that contribute to the distribution of HCF in normal eyes. In this retrospective study, we included healthy eyes with a normal fundus. HCF were defined as hyperreflective spots on en face SS-OCT images. The number, mean area, total area, and circularity of the HCF were compared with various choroid measurements obtained using SS-OCT, SS-OCT angiography, and fundus photography. We investigated 51 eyes from 51 patients. The mean patient age was 56.0 ± 14.7years, and 32 (62.7%) were female. The number and total area of HCF did not differ between the female and male patients and the right and left eyes. The number of HCF was correlated with the stromal area of the choroid (r = 0.291, P = 0.040) and subfoveal choroidal vascularity index (r = - 0.364, P = 0.009). The total area of HCF was correlated with the stromal area of the choroid (r = 0.283, P = 0.045). However, the number and total area of HCF were not correlated with age, degree of macular tessellation, subfoveal choroidal thickness, and choriocapillaris vascular density and flow void area. HCF were observed in normal eyes, and their distribution was associated with the underlying stromal component of the choroid. The results of this study can be used as a reference for determining abnormal hyperreflective foci in the choroid of the eyes with various diseases.

Vascular and structural alterations of the choroid evaluated by optical coherence tomography angiography and enhanced-depth imaging optical coherence tomography in eyes with reticular pseudodrusen and soft drusen

BackgroundTo assess the vascularity of choriocapillaris and structural choroidal differences in eyes with reticular pseudodrusen (RPD) and soft drusen. Methods21 eyes with RPD (group 1), 17 eyes with soft drusen (group 2), and 19 eyes as a control group (group 3) were included in this study. Choriocapillaris vascular density and flow area were measured by optical coherence tomography angiography. Total choroidal area, luminal area, stromal area, and lumen/stroma ratios were measured on optical coherence tomography B-scans converted to binary images. ResultsMean choriocapillaris vascular density was higher in group 3 than other groups (group 1 vs 3, p = 0.001; group 2 vs 3, p = 0.003). Mean flow area in choriocapillaris was higher in group 3 than other groups (group 1 vs 3, p = 0.001; group 2 vs 3, p = 0.001). Mean luminal, stromal, and total choroidal areas decreased in group 1 and group 2 compared to controls (p < 0.001, p < 0.001, and p < 0.001, respectively). The stroma ratio decreased in group 1 compared to group 3 (p = 0.013). The lumen ratio and lumen/stroma ratio increased in group 1 compared to group 3 (p = 0.012 and p = 0.008, respectively). ConclusionsThe choroid of eyes with RPD and soft drusen was affected in both choriocapillaris and whole choroid layer.

Morphological differences of choroid in central serous chorioretinopathy determined by ultra-widefield optical coherence tomography.

The purpose of this study was to compare the morphology of the central and peripheral choroid of eyes with central serous chorioretinopathy (CSC) to that of normal eyes using ultra-widefield optical coherence tomography (UWF-OCT). We reviewed the medical records of 29 eyes of 25 patients (23 men, 2 women; average age 44.4years) with CSC and 34 eyes of 22 healthy subjects (19 men, 3 women; average age, 49.5years) with normal eyes. The images obtained by a prototype swept source UWF-OCT (Topcon, Tokyo, Japan) of about 31.5-mm wide and a depth of 10.9mm were analyzed. The choroidal thickness was measured for each sector of the eye using the conventional automated layer analysis method. The local morphological differences were quantified by the maximum steepness (µm/deg) which was obtained by differentiating the changes in the choroidal thickness from the periphery to the fovea. Only the vertical scans were evaluated to avoid the influence of the optic disc. The choroid was thicker in the macular area than the peripheral area in both normal and CSC eyes. The choroid at the subfovea was significantly thicker in the CSC eyes than that of the normal eyes (P < 0.0001); however, the difference at the periphery was not significant. The mean of the maximum steepness of the choroidal thickness was 20.8 ± 3.8µm/deg in the CSC eyes which was significantly steeper than the 16.0 ± 4.6µm/deg in healthy eyes (P < 0.0001). The choroid in CSC eyes has a steeper slope around the posterior pole. UWF-OCT can be used to evaluate the abnormalities of the choroidal structures from the posterior pole to the periphery in eyes with CSC.

Assessment of the outer retina and choroid in white matter lesions participants using swept-source optical coherence tomography.

PurposeTo assess the three‐dimensional outer retina thickness and choroid in eyes with white matter lesions (WMLs) using swept‐source optical coherence tomography (SS‐OCT).MethodsParticipants without dementia and stroke with cerebral WMLs were enrolled in our study. Optical coherence tomography (OCT) and OCT angiography (OCTA) were used to image and evaluate the outer retinal layer, choroidal structure, and perfusion of the choriocapillaris, microvessels of the choroid, respectively. Measurement of the outer retinal thickness, choroidal thickness and perfusion of the choriocapillaris was done by the SS‐OCT tool.ResultsThirty‐one eyes from 16 WMLs and 40 eyes from 20 healthy controls were included in the data analyses. Outer retinal thickness was significantly reduced (P < .001) in WMLs participants when compared to healthy controls. Choroidal thickness was also significantly reduced (P < .001) in WMLs participants when compared to healthy controls. Choriocapillaris perfusion was significantly reduced (P = .002) in WMLs when compared to healthy controls. A significant correlation (Rho = .392, P = .032) was seen between the outer retinal thickness and choriocapillaris perfusion in WMLs participants.ConclusionsAssessing retinal thickness and choroidal changes with the SS‐OCTA as a proxy for WML could prove to be a potentially valuable tool for early detection of cognitive decline and other neurodegenerative diseases.

Characterization of Retinal Microvascular and Choroidal Structural Changes in Parkinson Disease

Noninvasive retinal imaging may detect structural changes associated with Parkinson disease (PD) and may represent a novel biomarker for disease detection. To characterize alterations in the structure and microvasculature of the retina and choroid in eyes of individuals with PD and compare them with eyes of age- and sex-matched cognitively healthy control individuals using optical coherence tomography (OCT) and OCT angiography (OCTA). This cross-sectional study was conducted at the Duke Neurological Disorders Clinic in Durham, North Carolina. Individuals aged 50 years or older with a diagnosis of PD were eligible for inclusion and underwent an evaluation and diagnosis confirmation before enrollment. Control individuals aged 50 years or older and without subjective cognitive dysfunction, a history of tremor, or evidence of motor dysfunction consistent with parkinsonism were solicited from the clinic or the Duke Alzheimer's Disease Prevention Registry. Individuals with diabetes, glaucoma, retinal pathology, other dementias, and corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity worse than 20/40 Snellen were excluded. Data were analyzed between January 1, 2020, and March 30, 2020. All participants underwent OCT and OCTA imaging. Generalized estimating equation analysis was used to characterize the association between imaging parameters and PD diagnosis. Superficial capillary plexus vessel density (VD) and perfusion density (PFD) were assessed within the ETDRS 6 × 6-mm circle, 6 × 6-mm inner ring, and 6 × 6-mm outer ring, as was the foveal avascular zone area. Peripapillary retinal nerve fiber layer thickness, macular ganglion cell-inner plexiform layer thickness, central subfield thickness, subfoveal choroidal thickness, total choroidal area, luminal area, and choroidal vascularity index (CVI) were measured. A total of 124 eyes of 69 participants with PD (39 men [56.5%]; mean [SD] age, 71.7 [7.0] years) and 248 eyes of 137 control participants (77 men [56.2%]; mean [SD] age, 70.9 [6.7] years) were analyzed. In the 6 × 6-mm ETDRS circle, VD (β coefficient = 0.37; 95% CI, 0.04-0.71; P = .03) and PFD (β coefficient = 0.009; 95% CI, 0.0003-0.018; P = .04) were lower in eyes of participants with PD. In the inner ring of the 6 × 6-mm ETDRS circle, VD (β coefficient = 0.61; 95% CI, 0.20-1.02; P = .003) and PFD (β coefficient = 0.015; 95% CI, 0.005-0.026; P = .004) were lower in eyes of participants with PD. Total choroidal area (β coefficient = -1.74 units2; 95% CI, -3.12 to -0.37 units2; P = .01) and luminal area (β coefficient = -1.02 units2; 95% CI, -1.86 to -0.18 units2; P = .02) were greater, but CVI was lower (β coefficient = 0.5%; 95% CI, 0.2%-0.8%; P < .001) in eyes of individuals with PD. This study found that individuals with PD had decreased retinal VD and PFD as well as choroidal structural changes compared with age- and sex-matched control participants. Given the observed population differences in these noninvasive retinal biomarkers, further research into their clinical utility in PD is needed.

Choroidal Structure after Half-Dose Photodynamic Therapy in Chronic Central Serous Chorioretinopathy.

The study aims to analyze the changes produced by half-dose photodynamic therapy (HD-PDT) in the choroid of eyes with chronic central serous chorioretinopathy (CSC) applying the binarization method to spectral domain optical coherence tomography (SDOCT) and OCT Angiography (OCTA) images. SDOCT and OCTA were performed before, one hour, one week, and one month after HD-PDT. Binarization with a modified Niblack method and analysis by ImageJ were applied. An average ratio between luminal part and total structure was calculated. Twenty-two eyes of 21 patients (20 male and 1 female; mean age 54.8 years) were enrolled. A statistically significant reduction of the central choroidal thickness was observed one week (from 407 µm to 362 µm, p = 0.034) and one month (from 407 µm to 341.5 µm, p = 0.0004) after HD-PDT. The baseline average ratio between luminal part and total structure was 33.4% in SDOCT, and 61.1% in OCTA. These values were 35.3% and 61% one hour, 33.9% and 60.4% one week, and 34.5% and 60.6% one month after HD-PDT, respectively. Overall, PDT seems to produce short-term changes on the luminal component of both choriocapillaris and choroid, which return to baseline status after one month from treatment. However, choroid stays significantly thinner after one month, with both luminal and interstitial components significantly reduced.

Choroidal Rift: A New OCT Finding in Eyes with Central Serous Chorioretinopathy.

Central serous chorioretinopathy (CSC) is a complex and not entirely understood retinal disease. The aim of our research was to describe a novel optical coherence tomography (OCT) finding named “choroidal rift”, which may be identified in the choroid of eyes with CSC. We collected data from 357 patients (488 eyes) with CSC who had structural OCT and OCT angiography (OCTA) scans obtained. Choroidal rifts were identified as polygonal (and not round-shaped) hyporeflective lesions without hyperreflective margins. Choroidal rifts had to be characterized by a size superior to that of the largest choroidal vessel. Finally, hyporeflective lesions were graded as choroidal rifts only if these lesions had a main development perpendicular to the retinal pigment epithelium. OCT analysis allowed the identification of choroidal rifts in ten eyes from nine patients, all with chronic CSC, with an estimated prevalence rate of 2.1%. In three out of ten cases with choroidal rifts, these lesions spanned all the choroidal layers. In the remaining cases, choroidal rifts only partially spanned the choroidal thickness. In OCTA, choroidal rifts were characterized by the absence of flow. Combining structural OCT and OCTA information, we hypothesized that choroidal rifts may represent interruptions of the choroidal stroma in correspondence of fragile regions (in between expanded larger-sized choroidal vessels). Choroidal rift represents a novel OCT feature, which may characterize eyes with chronic CSC and may have a role in the development of irreversible chorio-retinal changes.

Possibilities for Identifying the Malignant Vasculature of Choroidal Melanoma

Choroidal melanoma is the most common and life-threatening intraocular malignant neoplasm affecting the eye choroid in about 90 % of cases. The incidence varies from 0.7 to 1.1 per 100,000 of the population. This category of malignant neoplasms is highly aggressive in terms of local distribution, the occurrence of loco-regional and distant metastases. According to various authors, the frequency of metastasis reaches up to 50 %, the risks of metastatic disease depend on the size of the tumor, the duration of observation, clinical and pathomorphological characteristics of the choroidal melanoma and genetic factors. This article provides a detailed literature review on the developmental aspects and growth dynamics of choroidal melanoma from the point of view of neoangiogenesis and the phenomenon of vasculogenic mimicry, and the possibilities of instrumental diagnostics for determining the malignant vasculature of a tumor. The relevance of studying this issue is determined by the peculiarities of the origin of choroidal melanoma, which can occur both de novo and due to malignant transformation from nevus cells and the critical point for it is a tumor thickness of more than 2 mm, at in which the the process of neoangiogenesis starts. This review details the role of various methods of instrumental diagnostics, such as doppler ultrasound imaging to determine the presence or absence of blood flow in the tumor and its blood flow characteristics, angiography using contrasts: fluorescein and indocyanine green angiography, and optical coherent tomography—angiography to identify the malignant vasculature and evaluation of tumor angioarchitectonics. It has been shown that in the diagnosis of especially small choroid melanomas, which are of significant diagnostic complexity, a multimodal approach using the above research methods is important. There is no doubt that these instrumental technologies aimed to identify the malignant vasculature of choroidal melanoma play a large role not only in diagnosis, but also are of considerable practical interest in planning treatment, in assessing its effectiveness, and also in predicting the risks of metastatic process development.

Choroidal vascularity index as an indicator of vascular status of choroid, in eyes with nanophthalmos.

To investigate choroidal vascular index (CVI) in eyes with nanophthalmos (NO) with the use of optical coherence tomography (OCT). Macular enhanced depth imaging OCT scans of 25 eyes of 25 patients with NO and age-gender-matched 25 eyes of 25 control subjects were analysed. Images were binarized using the ImageJ software, and total choroid area (TCA), luminal area (LA) and stromal area (SA) were acquired. The main outcome measure was CVI, defined as the ratio of LA to TCA. Twenty-five eyes of 25 patients with NO and age-gender-matched control subjects were enrolled. The mean TCA, SA and LA were found to be significantly higher in patients with NO (2.51 ± 0.44 vs. 1.91 ± 0.35 mm2, P < 0.001; 0.86 ± 0.17 vs. 0.63 ± 0.13 mm2, P < 0.001; and 1.65 ± 0.29 vs. 1.27 ± 0.23 mm2, P < 0.000, respectively). On the contrary, CVI did not significantly differ between the two groups (65.72, 67.68, P = 0.099). As a novel OCT-based marker, CVI could be used to assess vascular status of the choroid in eyes with NO and can provide better understanding of the pathogenesis of this disease.