Objective:To evaluate the toxicity of foscarnet sodium injection into the anterior chamber and intravitreal cavity on the cornea and retina.Methods:Thirty-six adult New Zealand White rabbits were randomly divided into control group, intravitreal injection group, and intracameral injection group, with 12 rabbits in each group.In the control group, 0.1 ml of balanced salt solution (BSS) was injected into the vitreous cavity of one eye, and an equal volume of BSS was injected into the anterior chamber of the other eye.In the intracameral injection group and intravitreal injection group, 0.1 ml of sodium foscarnet 1.2 mg was injected into the anterior chamber and vitreous cavity of one eye, respectively.Slit-lamp microscopy, ophthalmoscope, optical coherence tomography (OCT), and in vivo confocal laser scanning microscopy were performed on 3 experimental rabbits from each group on days 1, 7, 14, and 28 after injection.After sacrifice, both eyeballs were removed, and the corneas and retinas were examined using optical microscopy, scanning electron microscopy and transmission electron microscopy to evaluate the toxicity to the cornea and retina comprehensively.The use and care of the animals complied with the ARVO Statement.The study protocol was approved by an Ethics Committee of Peking University Third Hospital (No.IRB00006761-2015197). Results:Slit-lamp microscopy and OCT showed no corneal edema, intraocular inflammation, or other abnormalities in the intravitreal injection and control groups.Mild corneal edema was observed in intracameral injection group 1 day after injection, which resolved 7 days after injection. In vivo confocal laser scanning microscopy revealed normal hexagonal corneal endothelial cell morphology in the intravitreal injection and control groups.There was no significant difference in endothelial cell density at baseline and 1, 7, and 14 days after injection among the three groups ( Fgroup=1.21, P=0.32; Ftime=1.21, P=0.32).Light microscopy revealed no obvious corneal abnormalities.On days 1 and 7 after injection, retinal nerve fiber layer vacuolization and inflammatory cell infiltration were observed in the intravitreal injection and control groups.In the intravitreal injection of BSS group, inflammatory cell infiltration occurred in the retina without vacuolization 1 day after injection.There were no structural changes in the photoreceptor layer, and the nuclear layer was well-organized.Scanning electron microscopy showed no significant abnormalities in the corneal endothelium in the intravitreal injection group 1 day after injection.In the intracameral injection group, a large number of inflammatory cells were deposited and adhered to the corneal endothelium 1 day after injection and disappeared 7 days after injection.Transmission electron microscopy revealed that in the intravitreal injection group, 1 day after injection swelling of corneal endothelial cells, dilatation of the endoplasmic reticulum, and partial mitochondrial swelling were observed, which normalized 14 days after injection and vacuolization was present in the retina and interstitial fluid accumulation persisted until the 28 days after injection.In the intracameral injection group, swollen mitochondrial and endoplasmic reticulum of corneal endothelial cells was observed and resolved by 14 days after injection.However, structural abnormalities in the membranous discs of the photoreceptor outer segments and interstitial fluid accumulation in the optic nerve fiber layer persisted 1 day after injection and did not fully recover 28 days after injection. Conclusions:Intracameral intravitreal and injection of foscarnet sodium have transient toxic effects on the retina, which gradually weaken over time.Intracameral injection of foscarnet sodium was more toxic to corneal endothelial cells than intravitreal injection.

Objective:To evaluate the toxicity of foscarnet sodium injection into the anterior chamber and intravitreal cavity on the cornea and retina.Methods:Thirty-six adult New Zealand White rabbits were randomly divided into control group, intravitreal injection group, and intracameral injection group, with 12 rabbits in each group.In the control group, 0.1 ml of balanced salt solution (BSS) was injected into the vitreous cavity of one eye, and an equal volume of BSS was injected into the anterior chamber of the other eye.In the intracameral injection group and intravitreal injection group, 0.1 ml of sodium foscarnet 1.2 mg was injected into the anterior chamber and vitreous cavity of one eye, respectively.Slit-lamp microscopy, ophthalmoscope, optical coherence tomography (OCT), and in vivo confocal laser scanning microscopy were performed on 3 experimental rabbits from each group on days 1, 7, 14, and 28 after injection.After sacrifice, both eyeballs were removed, and the corneas and retinas were examined using optical microscopy, scanning electron microscopy and transmission electron microscopy to evaluate the toxicity to the cornea and retina comprehensively.The use and care of the animals complied with the ARVO Statement.The study protocol was approved by an Ethics Committee of Peking University Third Hospital (No.IRB00006761-2015197). Results:Slit-lamp microscopy and OCT showed no corneal edema, intraocular inflammation, or other abnormalities in the intravitreal injection and control groups.Mild corneal edema was observed in intracameral injection group 1 day after injection, which resolved 7 days after injection. In vivo confocal laser scanning microscopy revealed normal hexagonal corneal endothelial cell morphology in the intravitreal injection and control groups.There was no significant difference in endothelial cell density at baseline and 1, 7, and 14 days after injection among the three groups ( Fgroup=1.21, P=0.32; Ftime=1.21, P=0.32).Light microscopy revealed no obvious corneal abnormalities.On days 1 and 7 after injection, retinal nerve fiber layer vacuolization and inflammatory cell infiltration were observed in the intravitreal injection and control groups.In the intravitreal injection of BSS group, inflammatory cell infiltration occurred in the retina without vacuolization 1 day after injection.There were no structural changes in the photoreceptor layer, and the nuclear layer was well-organized.Scanning electron microscopy showed no significant abnormalities in the corneal endothelium in the intravitreal injection group 1 day after injection.In the intracameral injection group, a large number of inflammatory cells were deposited and adhered to the corneal endothelium 1 day after injection and disappeared 7 days after injection.Transmission electron microscopy revealed that in the intravitreal injection group, 1 day after injection swelling of corneal endothelial cells, dilatation of the endoplasmic reticulum, and partial mitochondrial swelling were observed, which normalized 14 days after injection and vacuolization was present in the retina and interstitial fluid accumulation persisted until the 28 days after injection.In the intracameral injection group, swollen mitochondrial and endoplasmic reticulum of corneal endothelial cells was observed and resolved by 14 days after injection.However, structural abnormalities in the membranous discs of the photoreceptor outer segments and interstitial fluid accumulation in the optic nerve fiber layer persisted 1 day after injection and did not fully recover 28 days after injection. Conclusions:Intracameral intravitreal and injection of foscarnet sodium have transient toxic effects on the retina, which gradually weaken over time.Intracameral injection of foscarnet sodium was more toxic to corneal endothelial cells than intravitreal injection.

Objective:To investigate the virological testing results of patients with corneal graft at the time of repeat keratoplasty and the diagnostic efficacy of multiple viral examinations.Methods:A case-control study was conducted.A total of 14 consecutive patients diagnosed with corneal graft failure were enrolled as graft failure group from March 2018 to December 2018 in Peking University Third Hospital, and 15 consecutive patients diagnosed with bullous keratopathy (BK) were enrolled as BK group in the meantime.All patients had unilateral involvement and indications for keratoplasty.Serum samples were collected from venous blood on the day of surgery, and specimens of aqueous humor and corneal tissue were obtained during corneal transplantation.Viral DNA in aqueous humor and corneal specimens was detected by real-time polymerase chain reaction (PCR).The level of viral antibodies in serum and aqueous humor was determined by enzyme-linked immunosorbent assay and the Goldmann-Witmer coefficient (GWC) was calculated.The tested viral species included herpes simplex virus (HSV), herpes zoster virus (VZV), and cytomegalovirus (CMV).For graft failure group, the relevance between elevated intraocular pressure, multiple previous keratoplasty surgeries, histories of viral keratitis and any positive result of viral analyses in this study were measured by the kappa consistency test.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Peking University Third Hospital (No.2017299-02).Written informed consent was obtained from each subject.Results:At the time of keratoplasty, 9 out of 14 eyes in the graft failure group tested positive for at least one type of virus, with 6 eyes positive for CMV and 3 eyes positive for VZV.Positive aqueous humor PCR analysis detected VZV in 5 out of 14 eyes.Corneal tissue PCR analysis detected CMV in 5 out of 14 eyes.Positive GWC calculations detected CMV in 3 out of 10 eyes.The concordance between viral DNA and antibody detection was poor.All eyes in BK group were negative for the virological test, except for 2 eyes (2/15) with elevated aqueous humor GWC for CMV.The prevalence of viral infection was 64.2%(9/14) in graft failure group, which was significantly higher than 13.3%(2/15) in BK group ( P=0.014).In graft failure group, 7 eyes (7/14) had elevated intraocular pressure, 3 eyes (3/14) had multiple keratoplasty surgeries, and 6 eyes (6/14) had viral keratitis before this keratoplasty.However, none of these factors showed significant relevance with positive virological results (kappa=0.143, -0.155, -0.286). Conclusions:Viral infection has become a major cause of corneal graft failure.A combination of various virological analyses during keratoplasty can help to clarify the etiology and the viral infection status, and ultimately guide subsequent treatment.