Choroidal Thickness Research Articles

Comment on: Evaluation of retinal and choroidal thickness changes in overweight and obese adults without ocular symptoms by swept-source optical coherence tomography

Comment on: Evaluation of retinal and choroidal thickness changes in overweight and obese adults without ocular symptoms by swept-source optical coherence tomography

Choroidal vascularity index in health and systemic diseases: a systematic review

Abstract Background The choroid, a highly vascular structure within the eye, is significantly influenced by various systemic conditions. The advent of enhanced depth optical coherence tomography has improved our ability to evaluate choroidal pathophysiology. The choroidal vascularity index (CVI), a noninvasive and reliable tool, serves as an effective means of assessing the choroidal vascular structure. Recent studies have increasingly focused on exploring CVI alterations under different systemic conditions. This study aims to provide a comprehensive summary of the latest research findings in this area. Methods A systematic literature review was conducted on October 1, 2023, using two databases, MEDLINE (via PubMed) and Scopus. Search terms were tailored specifically for each database to ensure a thorough exploration of relevant literature. The studies identified were qualitatively assessed, with particular emphasis on outcomes related to CVI and choroidal thickness. Results A total of 48 studies were included in the review, encompassing a diverse range of systemic conditions such as diabetes, central nervous system disorders, cardiovascular diseases, autoimmune disorders, and infectious diseases. Notable reductions in CVI were observed in diabetic retinopathy, autoimmune diseases, and neurodegenerative disorders. Additionally, the review highlighted variations in CVI values related to the severity of systemic diseases, indicating its potential use as a biomarker for disease progression. Conclusion This review highlights the significant correlation between variations in the choroidal vascularity index and diverse systemic conditions affecting hemodynamics. An enhanced understanding of CVI provides deeper insights into the pathophysiological mechanisms underlying these disorders and positions CVI as a promising biomarker for early detection and monitoring. Nevertheless, its clinical utility warrants careful assessment. Future research should address the potential limitations of CVI to fully capitalize on its diagnostic and prognostic potential.

Short-term effectiveness of intelligent navigated laser photocoagulation versus subthreshold micropulse laser in patients with chronic central serous chorioretinopathy

AIM: To compare the short-term effectiveness of intelligent navigated laser photocoagulation and 577-nm subthreshold micropulse laser (SML) treatment in patients with chronic central serous chorioretinopathy (cCSC). METHODS: This observational retrospective cohort study included 60 consecutive patients who underwent intelligent navigated laser photocoagulation (n=30) or 577-nm SML treatment (n=30) for cCSC between Jan. 2021 and Oct. 2022. During 3mo follow-up, all patients underwent assessments of best correct visual acuity (BCVA) and optical coherence tomography (OCT). RESULTS: The operation of laser treatment was successful in all cases. At 1mo, BCVA improved significantly more in the intelligent navigated laser photocoagulation group compared to the SML group (P<0.05). The change was not significantly different at 3mo (P>0.05). Central macular thickness (CMT) in the intelligent navigated laser photocoagulation group was lower than in the SML group at 1mo (P<0.05). The subfoveal choroidal thickness (SFCT) in two groups were all significantly improved at 3mo (all P<0.05). The change between two groups was not significantly different at 1mo or at 3mo (P>0.05). CONCLUSION: Intelligent navigated laser photocoagulation is superior to SML for treating cCSC, leading to better improvements in vision and CMT for short term.

Changes in choroidal thickness quantified by Optical Coherence Tomography across cognitive impairment: data from the NORFACE cohort.

Optical coherence tomography (OCT) enables high-resolution imaging of ocular structures in health and disease. Choroid thickness (CT) is a key vascular retinal parameter that can be assessed by OCT and might be relevant in the evaluation of the vascular component of cognitive decline. We aimed to investigate CT changes in a large cohort of individuals cognitive unimpaired (CU), with mild cognitive impairment due to Alzheimer's (MCI-AD), mild cognitive impairment due to cerebrovascular disease (MCI-Va), Alzheimer's disease dementia (ADD), and vascular dementia (VaD). Clinical, demographical, ophthalmological and OCT data from the Neuro-ophthalmological Research at Fundació ACE (NORFACE) project were analyzed. CT was assessed in the macula across nine Early Treatment Diabetic Retinopathy Study (ETDRS) quadrants, average thickness, total volume, and subfoveal choroidal thickness. Differences of CT among the five diagnostic groups were assessed in a multivariate regression model, adjusting for demographic and cardiovascular risk factors and OCT image quality. A comparison between manual and automatic CT measurements in a subset of participants was also performed. The study cohort comprised 1,280 participants: 301 CU, 196 MCI-AD, 112 MCI-Va, 578 ADD, and 93 VaD. CT was significantly increased in individuals with cognitive impairment compared to those CU, particularly in the VaD and MCI-Va groups and in the peripheral ETDRS regions. No significant differences were found in inner superior, center and subfoveal choroidal thickness. The interaction of sex and diagnosis had no effect in differentiating CT. Mini-Mental State Examination (MMSE) scores were not correlated to CT. Manual and automated CT measurements showed good reliability. Our findings indicated that peripheral choroidal thickening, especially in patients with cerebrovascular disease, may serve as a potential choroidal biomarker for cognitive decline and suggest different pathogenic pathways in AD and VaD. Further research is required to explore CT as a reliable ocular biomarker for cognitive impairment.

Corneal higher-order aberrations and their relationship with choroid in myopic patients.

To investigate corneal higher-order aberrations (HOAs) and choroidal characteristics in myopic individuals and explore the association between HOAs and choroidal parameters. Myopic participants were categorized into three groups based on axial lengths (ALs). We compared corneal HOAs, including spherical (Z40), comatic (Z3 - 1 and Z31), and trefoil (Z3 - 3 and Z33) aberrations, as well as choroidal vascularity index (CVI) and choroidal thickness (CT). Linear regression analysis was used to assess the relationships among corneal HOAs, CVI, CT, spherical equivalent, and AL. Groups 1, 2, and 3 included 105, 98, and 118 eyes, respectively. Group 3 exhibited lower spherical HOA root mean square and Z40 values than group 1(p < 0.05). Group 1 showed lower Z31 levels than other groups (p < 0.001). Groups 1 and 2 had higher mean, central, and I2 vertical CVIs than group 3 (p < 0.05). Group 1 had a larger vertical S1 CVI than group 3 (p < 0.05). Group 3 had smaller horizontal CVI values in all regions except N2 (p < 0.05). Both the mean and CT in all regions decreased as AL increased (p < 0.001). The comatic (Z31) and trefoil (Z33) components were predictors of mean horizontal CVI, and the comatic (Z31) component was correlated with both mean vertical and horizontal CT. Longer AL myopic patients exhibited lower absolute values of spherical aberration and horizontal coma. Alterations in choroid in myopic patients correlated with corneal HOAs. Our results suggest a potential connection between the optical quality and ocular perfusion in myopia.

Changes in choroidal thickness and lamina cribrosa position in subjects with overdipper pattern of arterial pressure.

The purpose is to analyze the changes produced in subjects with an overdipper pattern of ambulatory blood pressure monitoring with the aim of understanding the pathophysiology of normal tension glaucoma. A cross sectional study was performed in patients exhibiting overdipper and non-overdipper blood pressure patterns, respectively. Different optic parameters were assessed including the analysis of ganglion cell layer (GCL), peripapillary retinal nerve fiber layer (pRNFL) and Bruch's membrane opening-minimum rim width (BMO-MRW), as well as changes produced in choroidal thickness (CT) and lamina cribrosa (LC) position at two different periods of the day (early morning and evening). A total of 80 eyes (42 overdipper and 38 non-overdipper) were analyzed. A shortening of the distance at the beginning and end of the LC was objectified in the overdipper subjects (p < 0.003) as well as a statistically significant shift of the LC between morning and evening measurements in the overdipper subjects (p < 0.023). In addition, a significant thickening was found in 13 measurements of the horizontal and vertical plane CT (p < 0.029) of the overdipper subjects and a thickening of the CT in both groups in the morning. No significant differences in pRNFL, BMO-MRW and GCL measures were objectified. Morning assessment in overdipper subjects showed a deeper LC and a LC shift in comparison to evening values. In addition, an increase in CT was found in these subjects. Altogether, these findings could illustrate an etiopathogenic mechanism of the damage produced in normal tension glaucoma associated to the overdipper pattern.

Relationship between age and subfoveal choroidal thickness and its clinical implications

The retrospective study by Lei et al is an investigation of the relationship between age and subfoveal choroidal thickness (SFCT) in Chinese patients with proliferative diabetic retinopathy. Elements of the study design prevent the generalizability of the study findings, limiting their clinical implications. We recommend consideration of stricter eligibility criteria, other variables like duration of diabetes, interpretation of gender-differences in SFCT, longitudinal follow-up, use of newer choroidal flow indices, comparison of values with normal controls, subgroup analysis to determine the effect of prior treatment, as well as consideration of various real-world scenarios in future studies.

Choroidal Thickness and Visual Acuity in High Myopia Without Myopic Maculopathy: Insights From a Chinese Population Study.

To evaluate the association of choroidal thickness (ChT) with best-corrected visual acuity (BCVA) in patients with high myopia (HM) and without myopic maculopathy. This study was a retrospective, cross-sectional study of participants aged 7 to 70years with bilateral HM but without myopic maculopathy. Swept-source optical coherence tomography was used to measure ChT at the fovea. A BCVA of logMAR 0.1 was regarded as the benchmark for normal. The association between ChT and BCVA was evaluated by linear regression models with confounders fully adjusted. Subgroup analyses were performed across sex and age groups. A total of 412 eligible participants were enrolled in this study. The mean age, spherical equivalence, and subfoveal (SF) ChT of the included participants were 21.17 ± 9.55years, -9.77 ± 2.40 diopters, and 171.56 ± 61.33µm, respectively. The SF ChT was thinner in participants with abnormal BCVA (normal. 176.74 ± 60.24 µm; abnormal, 139.30 ± 58.63µm). A thinner ChT in all subregions of the posterior pole of the Early Treatment Diabetic Retinopathy Study grid was associated significantly with a worse BCVA after adjusting for age, sex, and axial length (SF ChT: coefficient, × 10-4, -2.64; 95% confidence interval, -4.73 to -0.55; P < 0.05 in all subregions). The strongest correlation was observed in the outer inferior region, where a per 21µm thinning of ChT led to a 0.01 worsening of BCVA. This correlation presented a stronger magnitude in male aged more than 40years. In patients with HM without myopic maculopathy, a thinner ChT was associated independently with a worse BCVA. The findings of this study suggest that thinning ChT should be considered a vital risk factor for irreparable visual acuity impairment.

Subfoveal Choroidal Thickness in Patients with Histiocytosis and Multimodal Imaging Features of Choroidal Infiltrates.

To evaluate choroidal findings in patients with histiocytosis including subfoveal choroidal thickness (SFCT), and multimodal imaging in eyes with choroidal infiltrates visible by ophthalmoscopy; and to determine if abnormalities change with histiocytosis-directed (kinase inhibitor) therapy. 91 patients with histiocytosis and 41 age- and gender-matched controls. Retrospective comparative study at single tertiary cancer referral center. Clinical exam, fundus photography and OCT were used to assess choroidal findings. Clinically evident choroidal infiltrates by ophthalmoscopy were recorded and choroidal vascular architecture was qualitatively examined. SFCT and was measured using enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT) from the outer portion of Bruch's membrane to the choroidal scleral interface. SFCT compared to matched controls; secondary outcome was change in SFCT on histiocytosis-directed (kinase inhibitor) therapy. Multimodal imaging of choroidal infiltrates visible by ophthalmoscopy. One hundred and eighty two eyes of 91 patients (46 males, 45 females) with histiocytiosis (Erdheim-Chester 35, Rosai-Dorfman 21, Xanthogranuloma 7, Mixed histiocytosis 11, Langerhans cell histiocytosis 15 and other 2) were examined. In histiocytosis patients, the mean SFCT was 336.2 +/- 94.9 μm compared with 250.3 +/- 60.7μm in the control group (p<0.0001). 69% of histiocystosis patients had SFCT > 275μm compared to 27% in controls (p< 0.0001). Subtype of histiocytosis, sites of bone or central nervous disease, posterior segment/other sites of ophthalmic disease, or mutational profile did not correlate with SFCT. In a subgroup analysis of 35 patients naïve to prior treatment, with > 6 mos follow-up, the proportion of SFCT > 275 μm significantly decreased (p-value = 0.0016) on histiocytosis-directed (kinase inhibitor) therapy. 19.8% of patients had clinically evident choroidal infiltration: majority were yellow creamy, geographic, located posteriorly and hyperautofluorescent; with enlarged Haller's vein bordering the infiltrate, choriocapillaris compression and loss of choroidal architecture by OCT. In this cohort, 19.8% of histiocytosis patients had clinically evident infiltration of their choroid. Furthermore, the majority of patients with histiocytosis had increased subfoveal choroidal thickness compared with age- and gender-matched controls. The thickened choroid decreases on histiocytosis-directed (kinase inhibitor) therapy and may be a marker of response to systemic treatment.

Choroidal and retinal alteration after long-term use of tadalafil: a prospective non-randomized clinical trial.

The purpose of this study is to investigate choroidal and retinal vascular features in patients taking PDE5is by measuring dynamic vascular alterations and neurostructural features of the retina before and after oral tadalafil administration. The current clinical research involved 22 patients treated with tadalafil 20 mg on alternate days (OAD) after nerve-sparing robotic radical prostatectomy (NS-RARP) for prostate cancer. Patients underwent SD-OCT to assess ganglion cell complex (GCC), retinal nerve fiber layer (RNFL), and subfoveal choroidal thickness (SFCT), as well as OCTA to assess superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris (CC), foveal avascular zone (FAZ), and radial peripapillary capillary thickness (RPC). All patients were evaluated at baseline (t0), and 3 (t1) and 6 (t2) months after the use of oral tadalafil. A statistically significant reduction in DCP and CC vessel density was found at t2 compared to baseline. According to the SFCT parameter, a statistically significant increase was observed from t0 to t1, and from t1 to t2. GCC parameter increased at t2 compared to baseline in a statistically significant way. No statistically significant differences were recorded between t0, t1 and t2 for the SCP, RPC, FAZ area, RNFL parameter. Retinal and optic disc toxicity may be detected using modifications of capillary vessel density. Further studies are needed to detect the possible progression or regression of ocular or systemic vascular complications in long-term follow-up.

Association of hypertension defined by the 2017 ACC/AHA guideline and choroidal thickness changes in type 2 diabetes: a 2-year longitudinal study.

This prospective cohort study investigated the longitudinal relationship between hypertension (HTN), defined by the 2017 ACC/AHA guidelines, and changes in choroidal thickness (CT) in patients with type 2 diabetes. Patients aged 30-80 years from the Guangzhou Diabetic Eye Study were categorized into non-HTN, stage 1-HTN, and stage 2-HTN groups based on BP criteria. Macular and parapapillary CT were measured using swept-source optical coherence tomography (SS-OCT). Mixed linear regression models analysed CT decline rates over a median 2.1-year follow-up, adjusting for confounders. 803 diabetes patients were included. Both stage 1-HTN and stage 2-HTN groups showed significantly thinner macular and parapapillary CT compared to non-HTN (all P < 0.05). Stage 2-HTN correlated with reduced macular CT thinning (coef = -11.29 μm/year; 95% CI, -22.36 to -0.22; P = 0.046) after adjustment, but not in the parapapillary area (coef = -4.07 μm/year; 95% CI, -12.89 to 4.74; P = 0.365). Subgroup analyses indicated faster macular CT decline in stage 2-HTN among those <65 years old (coef = -20.31 μm/year; 95% CI, -35.67 to -4.95; P = 0.10), males (coef = -14.1 μm/year; 95% CI, -32.54 to -4.33; P = 0.004), BMI ≥ 25 kg/m2 (coef = -10.24 μm/year; 95% CI, -26.86 to -6.38; P = 0.007), HbA1c > 6.5% (coef = -8.91 μm/year; 95% CI, -13.49 to -4.68; P = 0.001), and diabetes duration <10 years (coef = -12.78 μm/year; 95% CI, -27.48 to -1.91; P = 0.008). Stage 2-HTN is associated with accelerated macular CT loss in diabetic patients, suggesting macular CT measurements could potentially serve as early indicators of systemic hypertension. Further research is needed to establish precise CT cutoff values for clinical use in detecting and monitoring hypertension-related ocular changes.

Evaluation of the macula, retinal nerve fiber layer and choroid thickness in premature ovarian failure using spectral-domain optical coherence tomography.

The aim of our study is to describe the basal findings at the first diagnosis of the disease in patients with premature ovarian failure (POF) and to draw attention to the early changes in the macula, optic nerve head and choroid. In a prospective case-control study, 90 patients with POF and 90 control patients were evaluated. All participants underwent the same ophthalmic examination, including visual acuity, intraocular preasure measurement, anterior and posterior segment evaluation, macular and coroidal thickening, and retinal nerve fiber layer (RNFL) measurements with the same device (Spectral Domain OCT, software version 5.6.3.0, Heidelberg, Germany). The median age was 30.00 (28.00-31.00) in the control group and 29.00 (27.00-31.00) in the POF group (p = 0.249). The median thickness of the temporal outer macular region was statistically significantly thinner in the POF group (295.00 (289.00-303.25)) compared to the control group (306.00 (290.75-328.00)) (p < 0.001). There was a statistically significant decrease in all choroidal regions (p < 0.001), including the central, nasal 500, nasal 1500, temporal 500, and temporal 1500 regions in the POF group according to the control group. An increase in intraocular pressure in the postmenopausal period has been reported, suggesting a link between the postmenopausal decline in sex hormones and glaucoma. Our study is the first to monitor changes in choroidal, retinal thickness and RNFL in POF images showing early menopausal symptoms.

Clinical and genetic characteristics of simple central serous chorioretinopathy according to age

ABSTRACT Purpose To investigate whether genetic and clinical characteristics differ depending on generations using 326 patients (male/female, 259/67; mean age, 55.4 ± 12.5 years) with simple CSC. Methods All patients were diagnosed with simple CSC, defined as a retinal pigment epithelium alteration area equal to or smaller than 2-disc areas based on multimodal imaging at the initial presentation. We cross-sectionally evaluated clinical characteristics at the initial visit and genotyped CFH rs800292 and rs1329428 for all patients using TaqMan technology. Results As generations decreased, the proportion of males, subfoveal choroidal thickness, and prevalence of fibrin significantly increased (p < 0.001, p < 0.001, and p = 0.012, respectively), and the best-corrected visual acuity improved (p < 0.001); in contrast, the prevalence of pachydrusen significantly decreased (p < 0.001). The younger presentation was significantly associated with male and risk variants (T allele) of CFH rs1329428 (p = 9.1 × 10−7 and p = 0.042, respectively), and patients were estimated to present 2 years younger per one T allele of CFH rs1329428 (p = 0.042, β = −1.95, stepwise regression analysis). Conclusion Clinical and genetic characteristics differed significantly among patients with simple CSC, depending on their generation.

Correlation between choroidal thickness and the degree of myopia.

Myopia is a frequent visual problem, and the relationship between choroidal thickness (CT) and the degree of myopia has been a hot topic in myopia research. This work aimed to explore the correlation between CT and the degree of myopia, providing a reference for diagnosing and treating myopia. A cross-sectional study was conducted from September 2021 to December 2022, collecting data from 95 myopic patients aged between 18 and 50 years in the outpatient department. All subjects' CT in the macular center (MC), spherical equivalent (SE), and other ocular parameters were measured. Furthermore, the Pearson correlation coefficient (PCC) analyzed relationships between CT and various factors. The choroid was thickest in the MC and gradually became thinner towards the periphery, with the thinnest region located nasally in the healthy group. In the mild, moderate, and severe myopia groups, the choroid was thickest at 1,000 μm temporal to the fovea, becoming thinner towards the periphery, with the thinnest region located nasally. The MC's CT was correlated with a family history of myopia, SE, axial length (AL), and intraocular pressure (IOP). Meanwhile, there was a negative linear relationship between AL and CT in the MC (standard coefficient (SC) of -0.596, P-value of 0.000, tolerance of 0.217, and variance inflation factor (VIF) of 4.467), and a positive linear correlation between SE and CT in the MC (SC of 0.205, P-value of 0.013, tolerance of 0.257, and VIF of 3.792). This work provided clues for further understanding of the pathogenesis of myopic eyes and served as a scientific basis for early screening and treatment of myopia. Additionally, investigating the correlation between myopia and CT can also yield a reference for developing personalized myopia management strategies, which will help slow down myopia's progression and prevent related complications.

Reduced contrast sensitivity function and outer retina thickness in convalescent Vogt-Koyanagi-Harada disease.

To evaluate contrast sensitivity function (CSF) in convalescent Vogt-Koyanagi-Harada (VKH) disease and investigate the relationship between CSF and chorioretinal thickness in VKH patients with and without sunset glow fundus (SGF). This is a cross-sectional study. Seventy-six eyes of VKH patients and 56 eyes of normal controls were evaluated. Patients were divided into SGF and non-SGF groups. The best-corrected visual acuity (BCVA) of all the participants was ≤0.0 logMAR. Their CSF and macular chorioretinal thickness were measured with quantitative CSF (qCSF) and Optical Coherence Tomography (OCT) and compared using repeated measures analysis of variance at the group level. Relationships between CSF and macular chorioretinal thickness were evaluated using generalized estimating equations. The CSF was significantly impaired in the SGF group compared to that in the control group (p = 0.001), especially at medium and high spatial frequencies. No significant CSF difference was found between the non-SGF group and control group, nor between the SGF and non-SGF groups. Compared to the controls, outer retinal thickness (ORT) in both VKH subgroups was significantly reduced (P < 0.001 or 0.005, respectively), although their outer nuclear layer thickness (ONLT) and choroidal thickness (CT) were not significantly different (both P = 1.000, P = 0.829 or 0.112, respectively). We found no significant correlation between CSF metrics and outer retinal thickness. Despite good recovery of visual acuity, reduced CSF and outer retina thickness were found in convalescent VKH patients. CSF may be an important and sensitive metric to evaluate functional vision in VKH disease.

Angioarchitectural alterations in the retina and choroid in frontotemporal dementia.

Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder that affects the frontal and temporal lobes of the brain, leading to cognitive decline and personality changes. The objective of this cross-sectional study was to characterize angioarchitectural changes in the retina and choroid of individuals with FTD compared to cognitively normal controls using optical coherence tomography (OCT) and OCT angiography (OCTA). Cross-sectional comparison of patients with FTD and controls with normal cognition. All participants underwent Mini-Mental State Examination (MMSE) at the time of imaging. Outcome measures included OCT parameters: retinal nerve fiber layer (RNFL) thickness, ganglion cell layer-inner plexiform layer (GC-IPL) thickness, central subfield thickness (CST), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI); and OCTA superficial capillary plexus parameters: foveal avascular zone (FAZ) area, 3x3mm and 6x6mm macular perfusion density (PD) and vessel density (VD), 4.5x4.5mm peripapillary capillary perfusion density (CPD) and capillary flux index (CFI). Generalized estimating equation analysis was used to account for the inclusion of 2 eyes from the same participant. 29 eyes of 19 patients with FTD and 85 eyes of 48 controls were analyzed. In FTD, 3x3mm macular PD (p = 0.02) and VD (p = 0.02) and CFI (p = 0.01) were reduced compared to controls. There was no difference in average 4.5x4.5mm CPD, RNFL thickness, GC-IPL thickness, CST, SFCT, CVI, FAZ, or 6x6mm VD or PD between FTD and controls (all p > 0.05); however, there was a trend toward lower macular 6x6mm PD and VD in patients with FTD. Decline of peripapillary and macular OCT and OCTA parameters merit further investigation as potential biomarkers for FTD detection. Noninvasive retinal and choroidal imaging may hold promise for earlier detection, and future longitudinal studies will clarify their role in monitoring of FTD.

Quantifying choroidal and retinal thicknesses variations via optical coherence tomography in different stages of pediatric keratoconus

PurposeKeratoconus (KCN) is characterized by corneal thinning and bulging, leading to vision impairment. Assessing choroidal thickness (CT) in pediatric KCN ( pKCN) patients can provide insights for better understanding and managing the disease. CT may serve as a potential indicator of disease activity in KCN patients. This study aims to evaluate CT and retinal thickness (RT) in different stages of pKCN patients and compare the findings with an age-matched control group.Methods and patientsThis cross-sectional study included patients under 18 years old who met specific criteria. CT and RT was measured in all subjects using an optical coherence tomography device (Spectralis OCT, version 6.0, Heidelberg Engineering, Germany) with enhanced depth imaging mode, without pupil dilation. Mean CT and RT in pKCN was compared with healthy subjects and assessed among different disease grades using the ABCD grading method.ResultsThe study included 125 eyes (66 patients) in the pKCN group and 42 control eyes (21 individuals). Grade 2 KCN showed the highest prevalence at 26.4% (N = 33), while grades 3 and 1 had prevalence rates of 24% (N = 30). CT in all specified areas (all P-values < 0.001), as well as RT in the subfoveal area (P-value < 0.001) and 1500 μm nasal to the fovea (P-value = 0.025), were significantly greater in the pKCN group compared to controls. Furthermore, CT and RT differed significantly among the pKCN grades (P-values < 0.001).ConclusionCT was found to be elevated in pKCN patients, similar to adult KCN cases. CT could potentially serve as a clinical marker for disease activity in pKCN; however, further studies are needed.

Retinal vasculature changes in patients with internal carotid artery stenosis.

To evaluate the retinal vasculature in patient with internal carotid artery (ICA) stenosis and to highlight association between ICA stenosis severity and retinal vasculature changes. Seventy-five subjects were included in this prospective study. Twenty-five healthy subjects were included in the Group 1, 25 subjects with 1-49% ICA stenosis were included in the Group 2, and 25 subjects with 50-69% ICA stenosis were included in the Group 3. Visual acuity, intraocular pressure (IOP), and anterior and posterior segment examinations were performed. Macular superficial and deep capillary density, optic nerve head capillary density, and choroidal thickness data were measured using optic coherence tomography angiography. There was a statistically significant difference between the three groups regarding superficial vascular density, deep vascular density, vascular density of radial peripapillary capillary and choroid thickness (p < 0.05 for all). Mean parafoveal and perifoveal area vascular density of the superficial capillary plexus was significantly lower in the Group 3 than Group 1 (p < 0.05 for all). Mean whole area vascular density of the deep capillary plexus was significantly lower in Group 3 than both groups (p < 0.05 for all). Mean parafoveal area vascular density of the deep capillary plexus was significantly lower in the Group 3 than Group 1 (p < 0.05). Mean subfoveal choroid thickness in group 3 was significantly lower in the Group 3 than both groups (p < 0.05 for all). Compared to healthy controls, patients with moderate ICA stenosis revealed decreased density of superficial, deep and radial peripapillary capillary vasculature and subfoveal choroidal thickness.

Seasonal Variation in ATP-Induced Retinal Damage in the Cone-Dominant 13-Lined Ground Squirrel.

To examine whether time of year (relative to hibernation emergence) influences the retinal degenerative effects of intravitreal injection of adenosine triphosphate (ATP) in the 13-lined ground squirrel (13-LGS). Eighteen (9 male, 9 female) 13-LGS in three experimental cohorts (early season, mid-season, late season) (n = 6 each) underwent baseline imaging using scanning light ophthalmoscopy (SLO) and optical coherence tomography (OCT). Animals then received a 10-µL intravitreal injection of 0.723 M ATP, followed by OCT and SLO imaging at 3, 10, and 21 days. Adaptive optics SLO (AOSLO) was performed in animals without retinal damage after the 21-day follow-up. Retinal thickness, choroidal thickness, and cone density measures were compared to values from wild-type controls (n = 12). Five animals (four early season, one late season) showed retinal damage post-ATP injection (Fisher's exact test, P = 0.065). Animals with retinal damage displayed areas of disrupted retinal lamination on OCT. Any changes in OCT thickness were generally present on initial follow-up and resolved at later time points. Follow-up imaging with AOSLO on animals without retinal damage showed no significant differences in the cone mosaic topography from control eyes. Axial length was increased in mid-/late-season cohorts relative to early season (P = 0.0025 and P = 0.0007). In this pilot study, the 13-LGS appears more susceptible to ATP-induced retinal damage during the early season. Future studies adjusting dose based on ocular biometry may help elucidate the impact of time of year on chemical response. Consideration of ocular biometry in this and other animal models is merited when using intravitreal methods of chemical administration.

Influence of Aflibercept on Choroidal Blood Flow and Thickness in Branch Retinal Vein Occlusion: A Six-Month Follow-Up Study

Influence of Aflibercept on Choroidal Blood Flow and Thickness in Branch Retinal Vein Occlusion: A Six-Month Follow-Up Study