Alkali injury complicated by choroidal neovascularisation

Effect of Nintedanib Nanothermoreversible Hydrogel on Neovascularization in an Ocular Alkali Burn Rat Model

PURPOSE

To compare the therapeutic effects of different forms of nintedanib ophthalmic preparations on neovascularization corneal alkali burns in rats.

METHODS

Forty rat models of left eye corneal alkali burns were constructed, and the five groups (N = 8) were treated with normal saline, dexamethasone ointment (dexamethasone), 0.2% nintedanib aqueous solution and nintedanib nano thermoreversible hydrogel (NNTH). A slit lamp microscope was used to observe the area of neovascularization. The levels of the inflammatory factors were detected by ELISA. HE staining was performed on the rat corneas. Vascular endothelial growth factor (VEGFA) was detected by immunohistochemistry, and the expression of corneal VEGFA and CD31 was detected by western blotting. An MTT assay was performed to detect the cytotoxicity of nintedanib on human corneal epithelial cells (HCECs) and human umbilical vein vascular endothelial cells (HUVECs). Cell migration was detected by a cell scratch assay, and the proportion of apoptotic cells was detected by Annexin/PI double staining. Immunofluorescence and western blotting were performed to detect the protein expression of VEGFA and CD31.

RESULTS

NNTH had a stronger inhibitory effect on corneal neovascularization (CNV) in alkali-burned rats while reducing the level of inflammatory factors. NNTH had a longer drug duration of release than nanoformulations in vitro. Nintedanib at low concentrations (<8 μM) had no significant cytotoxicity to HCECs but significantly induced apoptosis and inhibited the expression of VEGFA and CD31 and the migration of HUVECs.

CONCLUSIONS

Nanomorphic thermoreversible hydrogel is superior among the nintedanib ophthalmic preparations, showing better inhibition of CNV in alkali-burned eyeballs and it blocked the migration and proangiogenic ability of HUVECs.

Indocyanine green angiographic features in a case of alkali retinopathy

PURPOSE

To report the fluorescein and indocyanine green angiographic features of a patient who developed posterior segment complications after an ocular alkali burn.

METHODS

Clinical examination, fluorescein angiography, and indocyanine green angiography were performed on a patient with an ocular alkali injury.

RESULTS

Clinical examination revealed an area of conjunctival and scleral necrosis in the injured eye. There was an area of retinal necrosis, which corresponded to the area of external necrosis. Fluorescein angiography demonstrated late leakage and obliteration of the retinal vessels in the area of necrosis. There was nonperfusion of the choroid with a surrounding rim of late indocyanine green leakage.

CONCLUSION

Alkaline substances can penetrate sclera. Ocular alkali burns can result in choroidal ischemia and retinal necrosis. It is important to suspect posterior segment complications in all ocular alkali injuries. This case emphasizes the necessity of prompt irrigation of the conjunctival cul de sac and the removal of any solid chemical remnants after ocular alkali injuries.