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Objective: The exact relationship between fibroblast growth factor 2 (FGF2) and choroidal neovascularization (CNV) remains unclear. In this study, using optical coherence tomography angiography (OCTA) and FGF2-tg mice which are transgenic mice with a rhodopsin promoter/FGF2 gene fusion, we aimed to investigate the dynamics of FGF2's role in angiogenesis over time. Methods: We developed laser-induced CNV models of FGF2-tg and wild-type (WT) mice and then separated them into two groups using different laser photocoagulation (PC) conditions. The first group received 3 intense PC shots (1st PC) altogether (one-time PC group), while the other group received 3 intense PC shots (1st PC) followed by 6 additional weak PC shots (2 nd PC) on the 7th day after 1st PC (two-times PC group). Results: Using OCTA to observe vessel changes within the same individual over time, there was no difference in the timing of vessel transition from the CNV development phase to the CNV regression phase between FGF2-tg and WT mice in the one-time PC group. In contrast, the neovascular vessels in the two-times PC group of FGF2-tg mice were maintained at least 28 days post-2nd PC without regression. In addition, mature vessels surrounded by PDGFRβ positive pericytes and α-SMA positive smooth muscle cells were observed. Real-time qPCR showed a substantial increase in apelin mRNA expression in the one-time PC group of FGF2-tg, rather than VEGF-A (p

Abstract Background Intravitreal anti-vascular endothelial growth factor (VEGF) is a mainstream treatment for reducing ME secondary to BRVO (BVO-ME). Regrettably, most reports of intravitreal anti-VEGF for BVO-ME have disclosed only short-term outcomes. Here, we characterized long-term indicators for the visual prognosis of patients with BVO-ME, including the correlation between retinal structure by OCT and visual acuity. Methods Patients with BVO-ME were retrospectively recruited based on clinical records in Kansai Medical University Hospital from June 2012 to March 2022. This study enrolled patients with vision loss who received intravitreal injection of anti-VEGF for BVO-ME. Inclusion criteria were that patients received intravitreal injection of anti-VEGF as their first treatment and were followed for at least 36 months. Exclusion criteria were those patients with ocular disease other than BRVO or who had been previously treated for BVO-ME. Patients were divided into two groups according to BCVA at the final visit: Group A (≥ 0.7) and Group B (

Objective: Retinal vein occlusion (RVO) can lead to visual impairment, but the development of collateral vessels can sometimes mitigate significant damage. This study aimed to investigate the relationship between collateral vessels and hypertension, the most common underlying condition associated with RVO, by comparing spontaneously hypertensive rats (SHRs) and wild-type Wister rats (WWRs). We also examined the differences between WWRs and SHRs in terms of sphingosine 1-phosphate receptor 1 (S1PR1) expression and its product nitric oxide synthase 3 (NOS3) expression, which are involved in the formation of collateral vessels after vascular occlusion. Methods: Laser photocoagulation (PC) was used to occlude one randomly selected retinal vein in WWRs and SHRs, and the area surrounding the occluded vessel was examined using optical coherence tomography angiography. If reperfusion of the occluded vessel occurred within 2 weeks, the vessel was re-occluded repeatedly by PC. The number of eyes with successfully occluded vessels accompanied by collateral vessels was recorded. Then, WWRs and SHRs were divided into the following four groups: 1) control (no treatment), 2) vehicle (20% DMSO), 3) S1PR1 agonist (2 mg/mL SEW2871), and 4) S1PR1 antagonist (0.25 mg/mL VPC 23019) groups. The drugs were administered intravitreally in all groups except the control. The number of laser shots required for successful RVO was recorded. Histological evaluation and quantitative real-time PCR of S1PR1 and NOS3 were performed to elucidate the mechanisms underlying collateral vessel formation. Results: The proportion of eyes achieving successful vein occlusion was lower in SHRs (4/12 eyes, 33.3%) than in WWRs (8/10 eyes, 80%, p = 0.043). NOS3 expression at 6 h after PC was significantly higher in WWRs than in SHRs (p = 0.021). In WWRs treated with SEW2871, vein occlusion failed in 7 of 10 eyes (70%). The expression of NOS3 was significantly higher in the SEW2871 treatment group than in the untreated group (p

Background: It is clinically recognized that collateral vessels can form after retinal vein occlusion (RVO) in some cases and these vessels can lead to spontaneous recovery of the pathological condition. In recent years, optical coherence tomography angiography (OCTA) has become a decisive clinical instrument. Unlike previous angiography tests, OCTA enables the non-invasive visualization of fundus vasculature without the need for administration of a contrast agent. However, it remains to be determined if OCTA depicts the ‘true’ histological status as several studies have reported artifacts in OCTA imaging. Methods: We generated a laser-induced mouse RVO model, and evaluated the subsequent formation of collateral vessels in order to understand the mechanisms by which collateral vessels form using OCTA imaging, as well as molecular and histological assessments. Results: We succeeded in visualizing the time course of collateral vessel formation in a mouse RVO model and confirmed the similarity in formation of collateral vessels only within the deep layer of the retina in both human and mouse. We hypothesized that sphingosine 1-phosphate receptor-1 (S1PR1) may play important roles via vascular shear stress linking vein occlusion and collateral vessel formation. Results from OCTA revealed that collateral vessels are increased in response to administration of a S1PR1 agonist in a mouse RVO model. Based on quantitative reverse transcription polymerase chain reaction (qRT-PCR), S1PR1 messenger ribonucleic acid (mRNA) levels in the whole retina peaked 6 h after photocoagulation in this model. Immunohistochemical staining of retinal flat mounts revealed that S1PR1 staining occurred along the laser-occluded blood vessels. Conclusion: We observed the temporal process of collateral vessel formation in a mouse RVO model and identified the relationship between S1PR1 and shear stress as one of the factors in collateral vessel formation in RVO.

Purpose: We evaluated a choroidal macrovessel using optical coherence tomography angiography (OCTA) and indocyanine green angiography (ICGA). Observations: A 79-year-old female presented with blurred vision in both eyes and metamorphopsia of the left eye. Mild cataract was noted in both eyes. Color fundus photography of the left eye revealed a red-orange tortuous vessel originating from the fovea and running in an inferior-temporal direction. Enhanced-depth imaging OCT revealed a large caliber choroidal vascular shadow and ambiguous line of the photoreceptor and retinal pigment epithelium layers. OCTA demonstrated a serpentine-shaped choroidal vessel. This anomalous vessel was seen by early phase ICGA as a rapidly perfused vessel connected to a vortex vein. We diagnosed this anomalous vessel as a choroidal macrovessel. We identified that cataract induced blurred vision in both eyes and choroidal macrovessel induced metamorphopsia in left eye. She was received cataract surgery for both eyes. The degree of metamorphopsia and the choroidal macrovessel of the left eye remains unchanged after a year of follow-up. Conclusions and importance: OCTA and ICGA are useful techniques to diagnose choroidal macrovessels.

Purpose: To establish a new evaluation method to quantify residual ophthalmic viscosurgical device (OVD) volume and corneal endothelium adhesion properties for phacoemulsification surgery. Methods: We compared the performance of four OVDs (Viscoat®, Healon5®, Healon® and DisCoVisc®) using porcine eyes. First, OVDs were mixed with fluorescent-conjugated dextrans to render them visible under the microscope. A corneal side port was opened, followed by a continuous curvilinear capsulorhexis, and a corneal tunnel incision was made. OVDs were injected, then the lens was removed using one-handed phacoemulsification. After this procedure, the anterior segment of the eye was isolated via an equatorial incision and the tissue was immediately frozen in shimmering liquid nitrogen. Sagittal slices (20 μm) were cut with a Cryostat from limbus to limbus. Every tenth slide was imaged using a fluorescent microscope with a CCD camera. We evaluated the percentage of the corneal endothelium covered by each OVD as the OVD adhesion to corneal endothelium ratio (OAE ratio) and the volume of residual OVD in the anterior chamber. Results: Viscoat® showed significantly higher endothelium coverage compared with both Healon® and DisCoVisc®. A statistically larger volume of Healon5® remained in the anterior chamber compared with Healon® and DisCoVisc®. Conclusion: The new evaluation methods used here provide precise quantitative analysis of OAE ratio and residual OVD volume. These results show that Viscoat® and Healon5® have a high potential for coating the corneal endothelium during phacoemulsification and aspiration surgery.

This study aimed to investigate the differences between images obtained by optical coherence tomography angiography (OCTA) with those from immunohistochemical labeling of laser-induced choroidal neovascularization (CNV) in a mouse model. CNV was induced by laser photocoagulation (GYC-2000, NIDEK; wavelength 532 nm) in the left eyes of 10 female C57BL/6J mice aged 6 weeks. The laser parameters included a 100-μm spot, 100-ms pulse duration and 200-mW incident power to rupture Bruch's membrane. OCT and OCTA CNV images were obtained using the RS-3000 Advance (NIDEK) 5 days post-laser photocoagulation. After OCTA imaging, the isolated choroid/retinal pigment epithelium complexes were fluorescently labeled with CD31 (an endothelial cell marker), platelet-derived growth factor receptor β (PDGFRβ, a pericyte-like scaffold marker), α-smooth muscle actin (α-SMA) and collagen I. Area measurements of the lesions obtained by enface OCTA were compared with immunolabeled CD31+ CNV lesions in choroid flat-mounts. We also examined structural correlations between the PDGFRβ+ pericyte-like scaffold and OCTA images. Laser-induced CNV was clearly detected by enface OCTA, appearing as a hyperflow lesion surrounded by a dark halo. Area measurements of the CNV lesion by immunolabeling were significantly larger than those obtained by enface OCTA (p = 0.006). The CNV lesion beneath the periphery of the pericyte-like scaffold was not clearly visible by enface OCTA due to the dark halo; however, the lesion was detectable as blood flow by cross-sectional OCTA and was also highly labeled by CD31. The periphery of the pericyte-like scaffold appeared to develop into subretinal fibrosis and this region was rich in myofibroblasts. Enface OCTA was unable to detect the entire area of laser-induced CNV in mice, with an undetectable portion located beneath the fibrotic periphery of the pericyte-like scaffold. Due to this OCTA fibrosis artifact, OCTA imaging has limited potential for accurately estimating CNV lesions.

Willow is a promising biomass resource for addressing the challenges of securing stable domestic biomass fuels in Japan and utilising abandoned agricultural land. Among the willow species, Salix pet-susu Kimura KKD (known as ezonokinu willow, EW) stands out for its growth, high production, storage stability, production stability, and business stability. Previous studies have investigated fuel characterisation through gasification (co-gasification) of various biomass mixtures to enhance feedstock flexibility for gasifier commercialisation. However, the synergistic effects of co-gasification using fuels containing EW blended with Japanese cedar, a commonly planted forest species in Japan, remain unexplored. Therefore, this study explored CO2 co-gasification with different blend ratios of EW/cedar blended char and evaluated the fuel characteristics for each blend ratio to elucidate the synergistic effects. The prepared char samples were utilised in the CO2 gasification test with TG-DTA as the analyser. The results suggest that in the initial stages of the willow/cedar blended char co-gasification reaction, pore size and specific surface area significantly influence the reaction rate. Subsequent stages of the reaction are influenced by the promoting and inhibiting effects of inorganic components, which impact co-gasification. The synergy factor results for the willow/cedar blended char co-gasification suggest a reaction pathway.