Corneal Epithelial Toxicity after Intravitreal Methotrexate Injection for Vitreoretinal Lymphoma: Clinical and In Vitro Studies

THE ROLE OF INTRAVITREAL METHOTREXATE AS AN ADJUNCT TO LOCAL OR SYSTEMIC CORTICOSTEROIDS IN VITRECTOMY FOR RHEGMATOGENOUS RETINAL DETACHMENT AND CHOROIDAL DETACHMENT: A Pilot Study

PURPOSE

To evaluate the role of repeated intravitreal methotrexate as an adjunct to pars plana vitrectomy in the management of rhegmatogenous retinal detachment with choroidal detachment.

METHOD

The authors compared anatomical and visual outcomes of rhegmatogenous retinal detachment with choroidal detachment eyes that underwent pars plana vitrectomy with (Group B) or without repeated intravitreal methotrexate (Group A).

RESULTS

The study included 25 eyes of 25 patients, 16 eyes in Group A and nine in Group B. Both groups had similar baseline characteristics. In Group A, successful retinal attachment was achieved in 50% as compared with 89% in Group B; however, the difference was not statistically significant ( P = 0.08). Also, Group B had a significantly greater change in visual acuity from baseline to the last follow-up visit (1.6 + 1.5 logMAR units) compared with Group A (1.18 + 1 logMAR units) ( P = 0.05). There were no significant safety concerns with the use of intravitreal methotrexate.

CONCLUSION

Repeated intravitreal methotrexate after vitrectomy for rhegmatogenous retinal detachment with choroidal detachment improves outcomes without posing major safety concerns. Nonetheless, further investigation is necessary to establish the optimal intravitreal methotrexate dosage and duration to prevent recurrence effectively.

Modulatory effect of amifostine (WR-1065) against genotoxicity and oxidative stress induced by methotrexate in human umbilical vein endothelial cells (HUVECs)

Amifostine is used in chemotherapy and radiotherapy as a cytoprotective adjuvant alongside DNA-binding chemotherapeutic agents. It functions by reducing free radicals and detoxifying harmful metabolites. Methotrexate, as an antimetabolite drug has been considered for treating various cancers and autoimmune diseases. However, the cytotoxic effects of methotrexate extend beyond tumor cells to crucial organs, including the heart. This study applied the HUVEC cell line as a reference in vitro model for researching the characteristics of vascular endothelium and cardiotoxicity. The current study aimed to assess amifostine's potential cytoprotective properties against methotrexate-induced cellular damage. Cytotoxicity was measured using the MTT assay. Apoptotic rates were evaluated by Annexin V-FITC/PI staining via flow cytometry. The genoprotective effect of amifostine was determined using the comet assay. Cells were exposed to various amifostine doses (10-200 μg/mL) and methotrexate (2.5 μM) in pretreatment culture condition. Methotrexate at 2.5 μM revealed cytotoxicity, apoptosis, oxidative stress and genotoxicity while highlighting amifostine's cyto/geno protective properties on HUVECs. Amifostine significantly decreased the levels of ROS and LPO while preserving the status of GSH and SOD activity. Furthermore, it inhibited genotoxicity (tail length, %DNA in tail, and tail moment) in the comet assay. Amifostine markedly attenuated methotrexate-induced apoptotic cell death (early and late apoptotic rates). These findings convey that amifostine can operate as a cytoprotectant agent.

Intraocular methotrexate for epithelial downgrowth: long-term outcomes in a multicentre case series

BACKGROUND/AIMS

Sheet-like type of epithelial downgrowth (EDG) is not easily amenable to surgical excision. We describe long-term outcomes in patients with EDG treated with intraocular methotrexate (MTX).

METHODS

This is a retrospective, multicentric case series including 10 eyes (nine patients) treated with intraocular MTX for sheet-like EDG. Relevant ocular history, previous EDG treatments, MTX injection regimen, long-term outcomes and complications are reported.

RESULTS

All cases were associated with intraocular surgery. Most patients were treated with 400 µm/0.1 mL MTX injections with a starting frequency of two times per week or weekly injections. Mean and SD number of injections per eye was 16±13 injections and duration of follow-up was 54±36 months (range: 7-120 months). Eradication of EDG was achieved in seven eyes of which one required a second MTX treatment course to achieve eradication, while clinical resolution with recurrence was observed in two. One treatment failure occurred despite eight weekly injections which slowed but did not halt EDG progression; the patient later requested that treatments be stopped given difficulty to come to follow-ups. Surface epitheliopathy developed in eight patients and was used to titrate MTX treatment. Six patients also developed endothelial failure.

CONCLUSION

We report the largest case series of diffuse, sheet-like EDG treated with intraocular MTX with follow-ups up to 10 years. Intraocular MTX may be used effectively to achieve eradication of EDG in cases where surgery is not amenable. However, further recommendations to guide treatment remain warranted.

Eyewash with balanced salt solution after intravitreal methotrexate injection in a case of vitreoretinal lymphoma: a simple but effective way to prevent ocular surface toxicity

Intravitreal methotrexate injection (400 µg/0.1 mL) is the current mainstay for managing vitreoretinal lymphoma. Various complications associated with intravitreal methotrexate are cataract, keratopathy, maculopathy, sterile endophthalmitis, optic atrophy, vitreous haemorrhage, etc. The most common adverse effect of intravitreal methotrexate is keratopathy occurring in more than half of cases. The severity may range from diffuse punctate keratopathy to severe epitheliopathy leading to photophobia, pain, visual blurring, epiphora, etc. This may become a reason for reduced compliance with treatment. The management of these complications includes oral folic acid, topical folinic acid supplementations and reduced frequency or cessation of methotrexate intravitreal injections. Here, we report a simple method of eyewash in a large amount of balanced salt solution after the intravitreal injection procedure to reduce the severity of keratopathy, which helped the patient tolerate the treatment.

The Challenge of Treating the Severest Forms of Chronic Noninfectious Posterior and Panuveitis

BACKGROUND

Noninfectious posterior and panuveitis may exhibit a chronic relapsing clinical course and are challenging to treat. Most affected patients are continuously treated with systemic immunosuppressive therapy, which is potentially associated with significant adverse side effects.

METHODS

A cohort of 18 patients presenting with severe noninfectious posterior or panuveitis were evaluated with respect to the clinical course of the disease, with particular focus on best-corrected visual acuity (BCVA), treatment duration, remission rates, reported negative side effects, and the necessity for switching medication.

RESULTS

The mean follow-up was 27.8 months. Although BCVA improved significantly, complete or partial remission was observed in only 66.7% of patients. Of the patients, 72.2% underwent a change in medical treatment due to either adverse events or inefficacy of medication.

CONCLUSION

Despite new immunosuppressive therapies, effective treatment of severe noninfectious posterior and panuveitis remains a major challenge. We discuss the urgent need for novel treatment strategies in order to prevent systemic adverse effects, and to improve visual outcome and quality of life.

Signaling pathways driving ocular malignancies and their targeting by bioactive phytochemicals

Ocular cancers represent a rare pathology. The American Cancer Society estimates that 3,360 cases of ocular cancer occur annually in the United States. The major types of cancers of the eye include ocular melanoma (also known as uveal melanoma), ocular lymphoma, retinoblastoma, and squamous cell carcinoma. While uveal melanoma is one of the primary intraocular cancers with the highest occurrence in adults, retinoblastoma remains the most common primary intraocular cancer in children, and squamous cell carcinoma presents as the most common conjunctival cancer. The pathophysiology of these diseases involves specific cell signaling pathways. Oncogene mutations, tumor suppressor mutations, chromosome deletions/translocations and altered proteins are all described as causal events in developing ocular cancer. Without proper identification and treatment of these cancers, vision loss, cancer spread, and even death can occur. The current treatments for these cancers involve enucleation, radiation, excision, laser treatment, cryotherapy, immunotherapy, and chemotherapy. These treatments present a significant burden to the patient that includes a possible loss of vision and a myriad of side effects. Therefore, alternatives to traditional therapy are urgently needed. Intercepting the signaling pathways for these cancers with the use of naturally occurring phytochemicals could be a way to relieve both cancer burden and perhaps even prevent cancer occurrence. This research aims to present a comprehensive review of the signaling pathways involved in various ocular cancers, discuss current therapeutic options, and examine the potential of bioactive phytocompounds in the prevention and targeted treatment of ocular neoplasms. The current limitations, challenges, pitfalls, and future research directions are also discussed.

Inhibition of proliferative vitreoretinopathy by a newly developed methotrexate loaded drug carrier in vitro

PURPOSE

Repeated intravitreal injections of methotrexate for proliferative vitreoretinopathy, a rare ocular condition that can cause vision loss, have shown beneficial effects in recent clinical studies. The purpose of this study was to develop a slow-release, long-term drug carrier composed of the polymer polylactide-co-glycolide and methotrexate that can be injected intravitreally.

METHODS

The required composition of the drug carrier was modeled using pharmacokinetic parameters based on current literature. Release kinetics were determined using an ocular pharmacokinetic model. Epiretinal PVR-membranes were harvested during pars plana vitrectomy and subsequently transferred to cell culture. The effect of the drug carrier on cell migration was investigated using time-lapse microscopy and a scratch-induced migration assay. The colorimetric WST-1-assay and a live-dead-assay were performed to determine viability, and the BrdU-assay was applied for proliferation.

RESULTS

The release profile showed an initial and a final burst of methotrexate with an intervening steady state that lasted 9-11 weeks. It showed inhibitory effects on pathobiological processes in human PVR-cells in vitro. Cell velocity in the time-lapse assay, migration in the scratch assay (p = 0.001), and proliferation in the BrdU assay (p = 0.027) were reduced after addition of the drug carrier. These effects occurred without causing a reduction in viability in the WST-1 assay (p > 0.99) and the live-dead assay.

CONCLUSION

The methotrexate-loaded drug carrier can maintain a stable concentration for 9-11 weeks and influence the pathobiological process of PVR cells in vitro. Therefore, it represents a potential therapeutic orphan drug for PVR.

Complications of intravitreal injections: 2022

PURPOSE OF REVIEW

This review highlights the complications of both intravitreal injection procedure as well as different intravitreal medications including antivascular endothelial growth factors, antibiotics, antivirals, antifungals, methotrexate, and steroids. Techniques for reducing rates of endophthalmitis will also be discussed.

RECENT FINDINGS

Intravitreal vancomycin can cause hemorrhagic occlusive retinal vasculitis resulting in severe vision loss. Intravitreal brolucizumab is associated with intraocular inflammation and retinal vasculitis resulting in significant vision loss. Face mask use by both patient and physician is not associated with increased risk of endophthalmitis and may decrease culture positive endophthalmitis.

SUMMARY

Intravitreal injections continue to be one of the most commonly performed procedures by ophthalmologists. Although the injections are generally well tolerated, sight-threatening complications can occur including endophthalmitis, retinal detachment, and/or retinal vasculitis. Adverse events associated with specific medications are outlined below. Several safety measures have been shown to reduce rates of endophthalmitis, the most concerning complication of this procedure.

Unusual presentation of cornea verticillata with intravitreal methotrexate in a case of primary intraocular lymphoma

A 56-year-old woman presented with floaters and diminution of vision in the right eye for 1 week. On examination, visual acuity was 20/400 in the right eye and 20/60 in the left eye. Indirect ophthalmoscopy revealed vitritis in the right eye and subretinal deposits in both eyes. Vitreous biopsy of the right eye revealed large B-cell-type primary intraocular lymphoma and the patient underwent multiple intravitreal methotrexate injections (400 μg/0.1 mL) in the right eye and systemic chemotherapy for bilateral disease. Following biweekly injections of methotrexate, her visual acuity improved considerably from 20/400 to 20/60 with resolution of vitritis. However, following eighth dose of intravitreal methotrexate, she experienced visual decline to 20/120 along with photophobia, redness and watering. Whorl-shaped opacities, limbitis and corneal haze were noted on slit-lamp examination. Intravitreal methotrexate was stopped, and the patient was started on frequent topical lubricants, loteprednol, topical folinic acid and oral folic acid. Complete resolution of corneal toxicity was observed at 3 weeks and the injections were suspended as there was no recurrence at 6 months follow-up.

Corneal endothelial cell density in patients receiving chemotherapy

PURPOSE

This study aimed to determine if the corneal endothelium was affected by chemotherapy.

METHODS

Chemotherapy patients were recruited to undergo specular microscopy before treatment and again at 1- and 2-year follow-up visits. One eye per patient, per follow-up, was selected for comparison to baseline.

RESULTS

Forty-six volunteers completed baseline and at least one follow-up assessment. From 51 eyes, there was no significant change in endothelial cell density for 41 eyes assessed at one year (M_D = 0.73%, 95% CI -1.33 to 2.78%) and 18 eyes at two years (M_D = 0.31%, 95% CI -3.53 to 4.15%).

CONCLUSION

Although other studies have shown that chemotherapy can adversely affect the corneal epithelium, this study showed no measurable change in endothelial cell density.

Corneal Toxicity of Intravitreal Methotrexate Used for the Treatment of Proliferative Vitreoretinopathy in Silicone Oil-Filled Eyes: A Case Series

PURPOSE

The purpose of this study was to evaluate the corneal toxicity of intravitreal methotrexate used for the prevention of proliferative vitreoretinopathy (PVR).

METHODS

In this retrospective case series, eyes with recurrent retinal detachment secondary to PVR were treated with intravitreal injections of 400 μg methotrexate at an average frequency of every 7 days after vitrectomy with silicone oil tamponade. Corneas were examined for corneal epitheliopathy by slit-lamp biomicroscopy before each injection.

RESULTS

Thirteen eyes of 12 patients were reviewed. All had a history of recurrent retinal detachment secondary to PVR treated with vitrectomy and silicone oil. The median age was 35 years (range: 9-83). Four patients (33%) were female. The median follow-up duration was 8 weeks (range: 5-10). The median BCVA (logMAR notation) was 2.00 preoperatively, 2.00 at 1 month postoperatively, and 2.00 at the most recent follow-up (P = 0.969). Ten eyes (77%) were pseudophakic. Nine eyes (69%) had a preexisting ocular comorbidity. The median number of injections was 8 (range: 5-10). The median interval time between each injection was 7.0 days (range: 5.8-10.5), and the median follow-up period beyond last injection was 16 weeks (range: 8-28). Two eyes (15.4%) developed mild corneal epitheliopathy during the course of the treatment.

CONCLUSIONS

Most eyes in this small series tolerated methotrexate injections without corneal toxicity. In eyes that developed epitheliopathy, the findings were mild and not treatment-limiting.

Efficacy and safety of intravitreal methotrexate for vitreo-retinal lymphoma - 20 years of experience

Vitreo-retinal lymphoma (VRL) is the most common intraocular lymphoma and is highly associated with central nervous system (CNS) lymphoma (CNSL), both posing a therapeutic challenge. We investigated patients' characteristics, efficacy and safety of intravitreal methotrexate (MTX) injections and their outcomes over 20 years. The records of 129 patients diagnosed between 1997 and 2018 were retrospectively reviewed. Lymphoma involved both the CNS and vitreo-retina (49%), solely the CNS (37%) or solely the vitreo-retina (14%). In all, 45·5% of the patients with CNSL either presented with VRL or developed it after a mean (±SE) of 85·7 (7·3) months. In all, 66·0% of the patients diagnosed with VRL either presented with CNSL or developed it after a mean (±SE) 42·6 (7·6) months. The 81 patients with VRL (134 eyes) received a mean (±SD) of 19 (7) injections; however, only 5 (4) injections were needed to reach complete remission. Local recurrence occurred in two of the 81 patients. Overall, 80·2% of eyes had an initial moderate-severe visual loss, and >50% of them improved. Reversible keratopathy was the most prevalent side-effect. A total of 18·5% developed intraocular pressure (IOP) elevation due to angle neovascularisation after 16 injections, which could be reversed with prompt intravitreal injection of bevacizumab. Intravitreal MTX injections are a safe and effective treatment for VRL. Fewer injections (15) may offer similar results with fewer side-effects.

Ocular surface complications of local anticancer drugs for treatment of ocular tumors

Local chemotherapy is increasingly used, either in combination with surgery or as monotherapy, for management of ocular tumors. Yet many of the local chemotherapeutic agents used for ocular tumors are cytotoxic drugs that are frequently associated with toxicities in normal ocular tissues. Understanding and managing these side effects are important because they affect treatment tolerability, outcome and quality of vision. Herein, we review local anticancer drugs administered for the treatment of ocular tumors, with an emphasis on their toxicities to the ocular surface, adnexa and lacrimal drainage system. We provide the underlying mechanisms and management strategies for the ocular side effects. Recent innovations in anticancer immunotherapy and ocular drug delivery systems also are discussed as new potential therapeutic modalities for alleviation of side effects.