Comparison of 24×20 mm2 swept-source OCTA and fluorescein angiography for the evaluation of lesions in diabetic retinopathy.

AIM: To compare ultra-widefield (24×20 mm2) swept-source optical coherence tomography angiography (SS-OCTA) and fluorescein angiography (FA) in the evaluation of diabetic retinopathy (DR) lesions. METHODS: Forty-six eyes of 23 patients with treatment-naïve DR were included at Peking University People's Hospital from September 1, 2021, until December 31, 2021, as well as 23 age and gender matched healthy controls. Quantitative assessments of DR lesions on FA and SS-OCTA (superficial capillary plexus, SCP, 24×20 mm2) were performed. RESULTS: Area of fovea avascular zone (FAZ) was larger in DR cases than controls (0.34±0.069 mm2 vs 0.287±0.108 mm2, P=0.006). In DR eyes, the mean FAZ area was 0.34±0.069 and 0.334±0.087 mm2 on SS-OCTA and FA, respectively (P=0.428), while the median FAZ perimeter was 2.382 (IQR, 2.201-2.59) and 2.333 (IQR, 2.138-2.6) mm on SS-OCTA and FA images (P=0.733). There was no significant difference in the size of the non-perfusion area (NPA) between the images on SS-OCTA and FA (12.389, IQR 4.96-28.3 and 11.125, IQR 5-28.31 mm2, P=0.197). The median total microaneurysm (MA) count was 35 (IQR, 19-46) and 73 (IQR, 43-93) on SS-OCTA and FA (P<0.001), respectively. No significant difference in intra-retinal microvascular abnormality (IRMA) and neovascularization (NV) count was found between the two techniques. The intraclass coefficient (ICCs) of all the parameters above indicated stable repeatability. CONCLUSION: Ultra-widefield SS-OCTA represents a reliable, noninvasive, and quantitative imaging technique in the assessment of microvasculature in DR, which offers a potential substitute for FA in DR evaluation.

Diurnal changes of retinal microvascular circulation and RNFL thickness measured by optical coherence tomography angiography in patients with obstructive sleep apnea-hypopnea.

Purpose: To evaluate capillaries perfusion and retinal nerve fiber layer (RNFL) thickness diurnal changes of macular/optic disc regions among participants with or without obstructive sleep apnea-hypopnea (OSA) using spectral-domain optical coherence tomography angiography (OCTA). Methods: In this study, we enrolled a cohort of 35 participants including 14 patients with mild-to-moderate OSA, 12 patients with severe OSA, and 9 healthy individuals. All participants had Berlin questionnaire filled. At 20:00 and 6:30, right before and after the polysomnography examination, a comprehensive ocular examination was conducted. The systemic and ocular clinical characteristics were collected, and OCTA scans were performed repeatedly. Blood flow and RNFL thickness parameters were then exported using built-in software and analyzed accordingly. Results: After sleep, the overall vessel density (VD) variables, especially macular and choriocapillaris VDs, were relatively comparative and stable. One exception was the RPC vessel density at the inside-disc region with a decreasing trend in the mild-to-moderate group (p=0.023). RNFL changes before and after sleep in the nasal-inferior and peripapillary region were statistically significant (p=0.003; p=0.043) among three groups. And multiple testing correction verified the significant difference in diurnal changes between the mild-to-moderate group and the control group in pairwise comparisons (p=0.006; p=0.02). Conclusions: The changes of imperceptible blood flow and RNFL thickness overnight around optic disc areas could be observed in OSA patients. Despite physiological fluctuations, aberrant diurnal changes might be useful for identifying a decrease in micro-environmental stability associated with the development of various ocular diseases such as glaucoma. Other VD variables, especially macular and choriocapillaris VDs, are relatively stable in eyes of patients having OSA with different severity.

An Insertion Variant in CRH Confers an Increased Risk of Central Serous Chorioretinopathy.

Purpose: To identify a novel corticotropin-releasing hormone (CRH) gene variant relevant in patients with central serous chorioretinopathy (CSC). Methods: We performed a genetic study of CSC in families and sporadic cases with controls. Using whole-exome sequencing and linkage analysis, we identified a heterozygous insertion variant, Gln52insPro, in the CRH gene that cosegregated in two Chinese families with CSC. This variant was evaluated among an additional 1307 patients with CSC and 1438 ethnicity-matched control individuals from three independent Chinese cohorts. Results: The CRH variant was strongly associated with CSC in these cohorts of Chinese patients (Pmeta = 1.24 × 10-11; odds ratio, 3.01; 95% confidence interval, 2.15-4.21). The risk variant Gln52insPro decreased CRH gene expression. Conclusions: Our results implicate the hypothalamic-pituitary-adrenal stress response system in the pathogenesis of CSC and provide a novel rationale for therapeutic intervention.

A novel mutation of CYP4V2 gene associated with Bietti crystalline dystrophy complicated by choroidal neovascularization.

AIM: To investigate the clinical characteristics and genetic features of a Bietti crystalline dystrophy (BCD) proband in a Chinese family. METHODS: A Chinese female diagnosed with BCD complicated by bilateral choroidal neovascularization (CNV) and her parents underwent complete ophthalmic examinations, including fundus autofluorescence (AF), fundus photography (FP), fundus fluorescein angiography (FFA), visual field testing, full-field electroretinography (ERG), optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). The sequencing of the CYP4V2 gene was performed to the whole family. RESULTS: Bilateral tiny glittering crystal-like deposits and differing extent of atrophy of the retinal pigment epithelium (RPE) were found in the posterior pole of her fundus. The diffuse hypo-fluorescence shown on AF images and window defects shown on FFA both indicated the atrophy of the RPE and choriocapillaris. OCT showed the thinning of the RPE and choriocapillaris layer, ellipsoid zone (EZ) band defect and CNV in both eyes. OCTA images proofed bilateral type 2 CNV. The visual field test showed central and paracentral scotoma. ERG showed a slightly decreased b-wave in scotopic ERG. Gene sequencing identified three mutations of the CYP4V2 gene, c.802_807del, c.810delT, and c.1388G>A. The mutation c.1388G>A was a novel substitution mutation. CONCLUSION: The novel mutation c.1388G>A may be a possible cause that could induce the clinical phenotype of BCD.

One-year results of intravitreal conbercept in treatment-naïve subjects with polypoidal choroidal vasculopathy.

PURPOSE: To evaluate the functional and structural outcomes of intravitreal conbercept monotherapy using a "3 + pro re nata (PRN)" regimen in treatment-naïve subjects with polypoidal choroidal vasculopathy (PCV) up to 12 months. METHODS: Thirty subjects (30 eyes) with PCV participated in this interventional, retrospective study. All subjects received intravitreal injections of 0.5 mg (0.05 ml) conbercept using a "3 + PRN" regimen for 12 months. The changes in best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) parameters, polyp lesion area, and regression rate were evaluated at baseline, month 3, and month 12. RESULTS: At the study end-point, BCVA improved significantly from 52.80 ± 17.17 ETDRS letters at baseline to 62.20 ± 18.96 letters (P < 0.001), with a mean gain of 9.40 ± 14.97 letters. The central retinal thickness (CRT) significantly reduced from 454.93 ± 147.31 µm at baseline to 308.73 ± 106.80 µm (P < 0.001) at end-point, and the total macular volume (TMV) decreased from 9.51 ± 1.04 mm3 at baseline to 8.32 ± 0.84 mm3 at end-point (P < 0.001). The mean volume of pigment epithelial detachment (PED) decreased from 0.73 ± 0.97 mm3 at baseline to 0.48 ± 0.71 mm3 (P < 0.05) at month 3. At month 12, the mean volume of PED was 0.57 ± 0.80 mm3 (P > 0.05 compared to baseline). After the 3-monthly loading injections, 6 eyes (20.0%) showed complete polyp regression, whereas a total of 19 eyes (63.5%) showed complete regression at month 12. The average injections given per subject were 7.70 ± 1.81. CONCLUSION: Intravitreal conbercept using the "3 + PRN" regimen was effective in the treatment of PCV.

Association between endogenous cortisol level and the risk of central serous chorioretinopathy: a Meta-analysis.

AIM: To assess the association between endogenous cortisol level and the risk of central serous chorioretinopathy (CSC). METHODS: Case-control studies were systematically searched on PubMed, Embase, Cochrane, China National Knowledge Infrastructure (CNKI) for publishes between January 1990 and July 2017 to assess the association between endogenous cortisol level and CSC. The main endpoints were serum cortisol level at 8 a.m. and 24-hour urine 17-hydroxysteroids level. We assessed pooled data using a random-effects model. RESULTS: Of 86 identified studies, 5 were eligible included in our analysis. The 5 studies included a total of 315 participants, of whom 187 had CSC. Statistically significant association was observed between serum cortisol level (summary SMD=0.77, 95%CI=0.55-0.99), 24-hour urine 17-hydroxysteroids level (summary SMD=0.95, 95%CI=0.61-1.30), and the risk of CSC. CONCLUSION: Endogenous cortisol level is associated with an increased risk of CSC. Combined treatment targeting the serum cortisol level at 8 a.m. and 24-hour urine 17-hydroxysteroids level can be a potential preventive strategy for individuals who are at risk of CSC and therapeutic strategy for patients with CSC.

Comparison of the 1-year Outcomes of Conbercept Therapy between Two Different Angiographic Subtypes of Polypoidal Choroidal Vasculopathy.

BACKGROUND: Polypoidal choroidal vasculopathy (PCV) is characterized by the presence of polyps with or without a branching vascular network and more prevalent among Asians. The aim of this study was to compare the outcomes of conbercept therapy between two different angiographic subtypes of PCV. METHODS: Fifty-eight patients of PCV were classified into two phenotypes according to indocyanine green angiography (ICGA). In Type 1, both feeder and draining vessels are visible on ICGA and network vessels are numerous. In Type 2, neither feeder nor draining vessels are detectable, and the number of network vessels is small. The patients were treated with intravitreal conbercept (IVC) for 3 months. Additional IVC was given at subsequent monthly visits, if needed. The patients were followed up for 12 months, and changes in mean best-corrected visual acuity (BCVA), central retinal thickness (CRT), subretinal fluid (SRF) thickness, pigmented epithelial detachment (PED), hemorrhage, and number of polypoidal lesions were evaluated. RESULTS: The mean BCVA in Type 2 PCV (15.92 ± 9.76 letters) achieved a significantly greater improvement than that in the Type 1 (14.10 ± 9.07 letters) at month 12 (t = 2.37, P< 0.01). Moreover, the mean CRT decrease was numerically greater in Type 2 (120.44 ± 73.81 µm) compared with Type 1 (106.48 ± 72.33 µm) at month 6 (t = 4.31, P< 0.01), and greater in Type 2 (130.21 ± 76.28 µm) compared with Type 1 (111.67 ± 79.57 µm) at month 9 (t = 1.87, P< 0.01). There was no significant difference between the two types for the decrease in SRF thickness, PED height, and regression of polyps from month 3 to 12 (t = 2.97, P > 0.05). CONCLUSION: Classification systems for PCV will show differences in presentation, natural history, or response to anti-vascular endothelial growth factor treatment and might, therefore, provide a new key to the choice of treatment for the disease.

[Analysis of RPE damage after photodynamic therapy in patients with idiopathic choroidal neovascularization].

OBJECTIVE: To study the correlative factors of damage to the retinal pigment epithelium (RPE) after photodynamic therapy (PDT) in patients with idiopathic choroidal neovascularization (CNV). METHODS: A retrospective analysis was performed in 45 eyes of 43 patients with idiopathic CNV and 27 eyes of 25 patients with pathological myopia CNV as a contrast group who were treated with standard PDT. Visual acuity, fluorescein angiography and optical coherence tomography (OCT) were taken to evaluated the RPE alterations in the treating area after PDT. RESULTS: Alterations of RPE with window defects in fluorescein angiography occurred in 21 of 45 eyes of idiopathic CNV after first PDT treatment and the same changes of RPE was seen in 1 eye after the second application of PDT, the incidence was 48.9%. In contrast, it occurred in only 2 eyes of pathological myopia CNV. Within the follow up period, 4 eyes of idiopathic CNV had the enlarged neovascular membrane after the therapy. Two groups had almost the same sexual ratio. Alterations of RPE occurred in 51.4% female and 40% male patients of idiopathic CNV. In contrast with pathological myopia CNV patients, idiopathic CNV patients were younger. Two cases that had the alterations of RPE in pathological myopia CNV were 37 years old and 15 years old. CONCLUSIONS: RPE alterations were observed in patients with idiopathic CNV following PDT. This might be related to a possible over reaction of RPE to the therapy in young patients.