Spontaneous retinal pigment epithelial tear in type 2 choroidal neovascularization: repair mechanisms following anti-VEGF therapy

PREDICTORS OF RETINAL PIGMENT EPITHELIUM TEAR DEVELOPMENT AFTER TREATMENT FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION USING SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To investigate the predictors of retinal pigment epithelium (RPE) tear development after treatment for neovascular age-related macular degeneration (AMD) using swept-source optical coherence tomography angiography (OCTA).

METHODS

This prospective study included 152 treatment-naïve eyes with neovascular AMD without high myopia that were followed up for one year after treatment. Eligible eyes were classified into eyes with or without RPE tear development. They were matched in a 1:2 ratio. The areas of choroidal neovascularization (CNV) and RPE detachment (PED) were measured from OCTA and OCT en-face images, respectively. The OCTA-specific parameters representing CNV status were analyzed.

RESULTS

Eight (5.3%) of the 152 eyes developed RPE tears (RPE tear group). After matching, 16 eyes without RPE tears were analyzed (non-RPE tear group). The ratio of the CNV/PED area was lower in the RPE tear group than in the non-RPE tear group (P=0.007). The PED area was broader (P=0.008) and PED height was greater in the RPE tear group (P=0.04). OCTA-specific parameters did not differ between the two groups.

CONCLUSIONS

Neovascular AMD with pre-treatment broad PED, high PED, and small CNV area relative to the PED area has a high risk of RPE tear development after therapy. However, CNV status may not have an association.

[Retinal pigment epithelial tear in age-related macular degeneration]

Retinal pigment epithelial tear (RPET) occurs in a number of diseases, most often in age-related macular degeneration (AMD). RPET develops in the setting of retinal pigment epithelium (RPE) detachment and represents a violation of the integrity of its monolayer accompanied by the formation of a demarcation line between the RPE atrophy area and RPE folds. Its incidence varies widely. In the earlier studies, diagnosis of RPET was performed using fluorescent angiography or angiography with indocyanine green (ICG-FA). The advent of optical coherence tomography made the detection of RPET easier and more accessible. The mechanism of RPET formation is quite polymorphic and ambiguous. Scientific literature contains descriptions of the occurrence of RPET when using both ranibizumab and aflibercept, and bevacizumab in equal proportions, implying that the drug choice does not affect the occurrence of complications. Continuous monitoring and adherence to anti-VEGF therapy leads to better anatomical and functional results in the long term, which is crucial for improving the quality of life of patients with age-related macular degeneration. This article reviews the literature and presents current data on RPET, identifies risk factors and mechanisms of its development, provides classification, and describes modern options for its diagnosis and treatment.

Clinical Course of Treated Choroidal Neovascularization in Eyes with Pre-existing Geographic Atrophy: Case Series and Reappraisal of the Literature

Purpose: To report the clinical course of choroidal neovascularization (CNV) treated with anti-vascular endothelial growth factor (VEGF) treatment in eyes with pre-existing geographic atrophy (GA).Material and Methods: Multicenter retrospective series. Electronic medical records, clinical notes, and multimodal retinal imaging of patients attending four tertiary referring centers with a diagnosis of unilateral CNV in the context of a pre-existing diagnosis of GA were included. GA was assessed on multimodal retinal imaging including spectral-domain optical coherence tomography (SD-OCT) scan with simultaneous near-infrared (NIR) reflectance imaging (OCT Spectralis, Heidelberg Engineering, Heidelberg, Germany) which was acquired at baseline and every follow-up visit. GA area was measured in treated eyes and fellow eyes using NIR.Results: Fifty-four eyes from 27 patients (23 females, mean age 80.89 ± 7.5) were included. The mean number of injections in the treated eyes was 5.52 ± 1.9 by month 12. From baseline to month 12, stabilization of best-corrected visual acuity (BCVA) and a significant decrease (P = .002) of central macular thickness (CMT) in the treated eyes were observed; there was a slight worsening of BCVA (-2 ETDRS letters) and a non-significant change (P = .4) of CMT in the fellow eyes. GA significantly increased in both treated and untreated eyes (P < .001 and P < .001, respectively) with a similar absolute increase (+2.68 mm² and +2.59 mm², respectively) and growth rate (0.4 and 0.34, respectively).Conclusions: In our study anti-VEGF treatment for CNV in eyes with pre-existing GA was effective in terms of decrease of exudative changes and stabilization of VA by month 12. A similar growth rate of GA between treated and untreated eyes does not support a causal relationship between anti-VEGF treatment and GA progression in this subset of patients. Further studies with a longer follow-up are mandatory to confirm these results.

Establishing a mouse model of choroidal neovascularization to study the therapeutic effect of levotinib and its mechanism

Objective

To study the therapeutic effect and mechanism of levotinib on choroidal neovascularization (CNV) in mice.

Methods

45 healthy C57BL/6 mice were selected and randomly divided into three groups: control group (group A), model group (group B) and levotinib group (group C). The model of CNV in mice was established. The fluorescence leakage of choroidal lesions in mice was observed by fundus fluorescein angiography. The morphological changes of retinal vessels in mice were observed by retinal slice preparation, the pathological changes of eyeball tissues in mice were observed by hematoxylin-eosin (HE) staining, the expression of vascular endothelial growth factor (VEGF) in mice retina was detected by real-time quantitative fluorescence PCR, and the protein expression of VEGF in mice retina was detected by Western blotting.

Result

On the 7th, 14th and 21st day after modeling, compared with group B, the fluorescence leakage area of group C mice was significantly reduced, and the difference was statistically significant (P < 0.05). The morphology of retinal vessels in group A was normal. In group B, the retinal vessels showed large areas of ischemia without perfusion and abundant neovascularization clusters and capillaries. Compared with group B, the morphology of retinal vessels in group C was significantly improved. Group A mice had normal eyeball structure, group B mice had visible spindle-like damage to the inner and outer retina, while group C mice had significantly less spindle-like damage than group B. Compared with group A, group B mice had significantly higher expression of retinal VEGF and the difference was statistically significant (P < 0.05), but compared with group B mice, the expression of VEGF in the retina of mice in group C was significantly decreased, and the difference was statistically significant (P < 0.05). Compared with group A, the expression of VEGF in retina of group B mice was significantly increased, and the difference was statistically significant (P < 0.05). Compared with group B, the expression of VEGF in retina of group C mice was significantly decreased, and the difference was statistically significant (P < 0.05).

Conclusion

Levatinib has obvious therapeutic effect on CNV, which may be achieved by inhibiting the high expression of VEGF in CNV.