Patient-Reported Complications after Intravitreal Injection and Their Predictive Factors

[Lens injury as a complication of intravitreal medication injection]

BACKGROUND

Intravitreal medication injections are an efficient and low-risk delivery technique for treating various retinal diseases. Rare serious complications include increased intraocular pressure, vitreous hemorrhage, retinal tears and detachment, intraocular inflammation and endophthalmitis. In the case series presented here, we report iatrogenic lens injuries caused by inadequate performance of intravitreal injections.

METHODS

A multicenter data collection of patients treated with intravitreal injections with visible iatrogenic lens defects from 2016 to 2023 was retrospectively performed.

RESULTS

Lens trauma after intravitreal injections was identified in six cases (69.3±6.5 years). While five cases were observed after anti-VEGF therapy, we identified lens injury after dexamethasone implantation in one patient.

CONCLUSION

Iatrogenic lens injury during intravitreal injection is preventable with the correct injection technique. Knowledge of individual axis length and lens status also helps to avoid this complication.

Platinum Nanozymes Counteract Photoreceptor Degeneration and Retina Inflammation in a Light-Damage Model of Age-Related Macular Degeneration

Degeneration of photoreceptors in age-related macular degeneration (AMD) is associated with oxidative stress due to the intense aerobic metabolism of rods and cones that if not properly counterbalanced by endogenous antioxidant mechanisms can precipitate photoreceptor degeneration. In spite of being a priority eye disease for its high incidence in the elderly, no effective treatments for AMD exist. While systemic administration of antioxidants has been unsuccessful in slowing down degeneration, locally administered rare-earth nanoparticles were shown to be effective in preventing retinal photo-oxidative damage. However, because of inherent problems of dispersion in biological media, limited antioxidant power, and short lifetimes, these NPs are still confined to the preclinical stage. Here we propose platinum nanoparticles (PtNPs), potent antioxidant nanozymes, as a therapeutic tool for AMD. PtNPs exhibit high catalytic activity at minimal concentrations and protect primary neurons against oxidative insults and the ensuing apoptosis. We tested the efficacy of intravitreally injected PtNPs in preventing or mitigating light damage produced in dark-reared albino Sprague-Dawley rats by in vivo electroretinography (ERG) and ex vivo retina morphology and electrophysiology. We found that both preventive and postlesional treatments with PtNPs increased the amplitude of ERG responses to light stimuli. Ex vivo recordings demonstrated the selective preservation of ON retinal ganglion cell responses to light stimulation in lesioned retinas treated with PtNPs. PtNPs administered after light damage significantly preserved the number of photoreceptors and inhibited the inflammatory response to degeneration, while the preventive treatment had a milder effect. The data indicate that PtNPs can effectively break the vicious cycle linking oxidative stress, degeneration, and inflammation by exerting antioxidant and anti-inflammatory actions. The increased photoreceptor survival and visual performances in degenerated retinas, together with their high biocompatibility, make PtNPs a potential strategy to cure AMD.

Outcomes of a Multicenter 10-Year Review of Postinjection Endophthalmitis and Associated Systemic Medical Comorbidities

Purpose: To investigate whether any systemic medical conditions may be associated with a higher risk for developing postinjection endophthalmitis. Methods: This case-control study is a retrospective review within the Emory Eye Center from 2009 to 2019 and The Cleveland Clinic Foundation from 2012 to 2019. Each case was matched in a 1:4 case-to-control ratio. The associations between medical comorbidities and endophthalmitis were explored using multivariable logistic regression models on the combined sample. Results: Sixty-six individuals were diagnosed with injection-associated endophthalmitis. Systemic immunocompromised status was found to be a risk factor associated with developing endophthalmitis with an adjusted odds ratio (aOR) of 3.17 (P = .009). Other conditions with increased risk approaching statistical significance included a history of pulmonary disease (aOR, 1.74; P = .08) and a history of smoking (aOR, 1.72; P = .06). Conclusions: This is the first report to our knowledge demonstrating that immunocompromised status is associated with an increased risk for developing postinjection endophthalmitis. While this study may be limited due to its retrospective nature, the result may nevertheless serve as a guidance for risk counseling. Future analysis using a large-scale database will be needed.

Advancements in Nanogels for Enhanced Ocular Drug Delivery: Cutting-Edge Strategies to Overcome Eye Barriers

Nanomedicine in gel or particle formation holds considerable potential for enhancing passive and active targeting within ocular drug delivery systems. The complex barriers of the eye, exemplified by the intricate network of closely connected tissue structures, pose significant challenges for drug administration. Leveraging the capability of engineered nanomedicine offers a promising approach to enhance drug penetration, particularly through active targeting agents such as protein peptides and aptamers, which facilitate targeted release and heightened bioavailability. Simultaneously, DNA carriers have emerged as a cutting-edge class of active-targeting structures, connecting active targeting agents and illustrating their potential in ocular drug delivery applications. This review aims to consolidate recent findings regarding the optimization of various nanoparticles, i.e., hydrogel-based systems, incorporating both passive and active targeting agents for ocular drug delivery, thereby identifying novel mechanisms and strategies. Furthermore, the review delves into the potential application of DNA nanostructures, exploring their role in the development of targeted drug delivery approaches within the field of ocular therapy.

Multiple Small Floaters Associated With Silicone Oil Droplets Following Intravitreal Pegcetacoplan Injection

This case series analyzes the presence of floaters associated with silicone oil droplets after intravitreal pegcetacoplan injection.

Severe Subconjunctival Hemorrhage After Intravitreal Injection in a Patient With Hemophilia A

Purpose: To report a patient with severe hemophilia A who received intravitreal antivascular endothelial growth factor (anti-VEGF) for exudative age-related macular degeneration (AMD). Methods: A case and its findings were analyzed. A systematic literature was performed. Results: A patient with severe hemophilia A received intravitreal anti-VEGF for exudative AMD, after which he developed a severe subconjunctival hemorrhage requiring hemostatic intervention. The effects of anti-VEGF in patients with preexisting blood-clotting disorders, such as classic hemophilia, have not been widely reported in the current literature. Conclusions: This case illustrates that precautions must be taken when performing ocular procedures on patients with serious hemostasis disorders.

Randomized Controlled Study of Cooled vs Room-Temperature Artificial Tears for Reducing Ocular Surface Irritation After Intravitreal Injection

Purpose: To evaluate the efficacy of cooled vs room-temperature artificial tears in reducing ocular discomfort after intravitreal injections (IVIs). Methods: Patients receiving a standard intravitreal injection in the retina clinic who met the eligibility criteria and provided informed consented were enrolled in the study. Patients were randomized to the cooled tears or room-temperature tears intervention group. Both groups rated their ocular discomfort following IVI after cooled or room-temperature tears were administered. Results: The cooled group comprised 48 patients and the room-temperature group, 61 patients. There was no significant difference in the reduction of ocular discomfort between the cooled vs room-temperature artificial tears groups (P = .387). In addition, there was a similar level of reduction in ocular discomfort after either intervention (P = .681) regardless of whether or not the patients routinely used artificial tears after previous IVIs. Conclusions: Cooled tears provided no additional benefit in reducing ocular discomfort post-IVI compared with room-temperature tears. Baseline tear use after an IVI may have no true benefit other than a potential placebo effect, recall bias, or both.

The Impact of Intraocular Treatment on Visual Acuity of Patients Diagnosed with Branch Retinal Vein Occlusions

Branch retinal vein occlusions are a significant cause of vision loss and present several ophthalmic and systemic risk factors, including age, hypertension, hyperlipidemia and glaucoma. Retinal vein occlusion is the second-most-common retinal vascular disease. This study evaluated the effects of Ozurdex in contrast to a combination therapy with anti-vascular endothelial growth factor (VEGF) and cortisone in treatment-naive branch retinal vein occlusions-macular edema (BRVO-ME) cases, at 4-month and 6-month follow-ups. Thirty eyes were included in the study, which were divided into two groups. The first group consisted of 15 eyes, and each received 1 injection of dexamethasone intravitreal implant Ozurdex (DEX). The second group of 15 eyes received 3 intravitreal injections, the first and second with the anti-vascular endothelial growth factor aflibercept and the third one with 4 mg of triamcinolone acetonide (Vitreal S), spaced at one month. The best corrected visual acuity (BCVA) results suggested that the peak efficacy was at 4 months for both groups, with mean values of 0.5 LogMAR and 0.4 LogMAR. Regarding macular edema, there were no significant changes between the 4- and 6-month follow-up periods, with mean values of 361 μm and 390 μm. Six patients experienced transient raised intraocular pressure at one week after treatment. This study highlights the benefits to visual acuity of the combination of anti-vascular endothelial growth factor and cortisone, which represents a viable solution with similar results to Ozurdex therapy.

Biomimetic, Injectable, and Self-Healing Hydrogels with Sustained Release of Ranibizumab to Treat Retinal Neovascularization

Retinal neovascularization (RNV) is a typical feature of ischemic retinal diseases that can lead to traction retinal detachment and even blindness in patients, in which the vascular endothelial cell growth factor (VEGF) plays a pivotal role. However, most anti-VEGF drugs currently used for treating RNV, such as ranibizumab, need frequent and repeated intravitreal injections due to their short intravitreal half-life, which increases the incidence of complications. Herein, a hydrogel intravitreal drug delivery system (DDS) is prepared by a dynamic Schiff base reaction between aminated hyaluronic acid and aldehyde-functionalized Pluronic 127 for sustained release of ranibizumab. The prepared hydrogel system named HP@Ran exhibits excellent injectability, self-healing ability, structural stability, cytocompatibility, and blood compatibility. According to an in vitro drug release study, the hydrogel system continuously releases the model drug bovine serum albumin for more than 56 days. Importantly, in an in vivo rabbit persistent RNV model, the HP@Ran hydrogel system continuously releases pharmacologically active ranibizumab for more than 7 weeks and also exhibits superior anti-angiogenic efficacy over ranibizumab treatment by decreasing vascular leakage and neovascularization at 12 weeks. Thus, the developed HP@Ran hydrogel system possesses great potential for intravitreal DDS for the treatment of RNV.

Pigment epithelium-derived factor engineered to increase glycosaminoglycan affinity while maintaining bioactivity

Pigment epithelium-derived factor (PEDF) is a secreted protein that is essential in tissue homeostasis and is involved in multiple functions in the eye, such as antiangiogenesis and neuroprotection. However, short retention in the retinal microenvironment can limit its therapeutic effects. In this study, we modified the amino acid sequence of PEDF to increase its affinity for heparin and hyaluronic acid (HA), which are negatively charged extracellular matrix (ECM) molecules. HA is the major component of the vitreous humor. We selectively converted neutral or anionic residues into cationic residues to obtain engineered PEDF (ePEDF). Using in vitro binding assays, we demonstrate that ePEDF had higher affinity for heparin and HA than wild-type PEDF (wtPEDF). ePEDF exhibited antiangiogenic and retinal survival bioactivities. It inhibited endothelial cell proliferation and tube formation in vitro. In an ex vivo model mimicking retinal degeneration, ePEDF protected photoreceptors from cell death. The findings suggest that protein engineering is an approach to develop active PEDF with higher ECM affinity to potentially improve its retention in the retina microenvironment and in turn make it a more efficient therapeutic drug for retinal diseases.

Board Certification Is Associated With a Reduced Risk of Endophthalmitis After Intravitreal Injections

Purpose:

This work investigates associations between physician qualifications and the risk of postintravitreal injection endophthalmitis.

Methods:

This retrospective analysis of data from medical claims studied Medicare beneficiaries undergoing 1 or more intravitreal injections between January 1, 2013, and December 31, 2017. Logistic regression analysis was performed to assess whether board certification status or retina subspecialty training was associated with lower risk of postinjection endophthalmitis, controlling for patient's age, race, and sex, type of agent injected, diagnosis, and year of injection. The main outcome measure was odds ratio (OR) of receiving a diagnosis of endophthalmitis in the 14 days after intravitreal injection. Clinical outcome and quality of care were not evaluated in this study.

Results:

A total of 2 907 324 intravitreal injections were performed on 219 640 patients by 4315 ophthalmologists, 3196 (74%) of whom were retina specialists and 4021 (92%) of whom were certified by the American Board of Ophthalmology (ABO). Overall, there were 1088 (0.037%) cases of postinjection endophthalmitis, of which 1024 (0.037%) were injected by ABO-certified ophthalmologists and 64 (0.050%) by non–board-certified ophthalmologists. Injections by ABO-certified ophthalmologist had 28% reduced odds of endophthalmitis (OR = 0.72; 95% CI, 0.523-0.996, P = .05). Higher odds of endophthalmitis were observed for corticosteroid injections (OR = 3.91; 95% CI, 2.75-5.56, P < .001) and aflibercept injections (OR = 1.47; 95% CI, 1.19-1.80, P < .001). Patients' sex and race, the diagnosis associated with the injection, and providers' retina subspeciality training were not associated with the rate of endophthalmitis ( P < .20 for all comparisons).

Conclusions:

We found evidence that endophthalmitis may be reduced when ABO-certified physicians perform an intravitreal injection.

Targeted drug delivery vehicles mediated by nanocarriers and aptamers for posterior eye disease therapeutics: barriers, recent advances and potential opportunities

Nanomedicine and aptamer have excellent potential in giving play to passive and active targeting respectively, which are considered to be effective strategies in the retro-ocular drug delivery system. The presence of closely adjoined tissue structures in the eye makes it difficult to administer the drug in the posterior segment of the eye. The application of nanomedicine could represent a new avenue for the treatment, since it could improve penetration, achieve targeted release, and improve bioavailability. Additionally, a novel type of targeted molecule aptamer with identical objective was proposed. As an emerging molecule, aptamer shows the advantages of penetration, non-toxicity, and high biocompatibility, which make it suitable for ocular drug administration. The purpose of this paper is to summarize the recent studies on the effectiveness of nanoparticles as a drug delivery to the posterior segment of the eye. This paper also creatively looks forward to the possibility of the combined application of nanocarriers and aptamers as a new method of targeted drug delivery system in the field of post-ophthalmic therapy.

Analysis of urgent follow up visits and complications after intravitreal injections: a retrospective cohort study

BACKGROUND

Intravitreal injections (IVIs), a common treatment in ophthalmology, result in acute complications and urgent follow-up visits causing significant burden to both patient and physician. We evaluated the incidence of acute complications following IVIs which occurred within seven days of injection.

METHODS

A retrospective cohort study conducted at a private retinal practice, in Cleveland, Ohio. Using the practice management software database, we examined 73,286 injections of patients with unscheduled or urgent visits within 7 days of an injection from August 1st,2018 to August 1st,2020. Data collected included: age, gender, eye, medication injected, diagnosis, reason for urgent follow-up, time between injection and urgent follow-up, and type of anesthesia administered. Data was analyzed using SPSS v.28 (SPSS Inc., Chicago IL).

RESULTS

Study included 73,286 injections, with 441 injections (n = 441) resulting in urgent follow-up visits (0.60%). Mean patient age was 72.1 (± 30.4) years, with 187 male (42.4%) and 254 female (57.6%) patients. IVI medications included: aflibercept (60.3%), ranibizumab (22.4%), bevacizumab (13.4%), dexamethasone intravitreal implant (2%), triamcinolone acetonide (1.6%) brolucizumab (1.59%), fluocinolone acetonide intravitreal implant 0.19 mg (0.2%), and fluocinolone acetonide intravitreal implant 0.18 mg (0.03%) (Table 1). Medications associated with urgent visits included: aflibercept (42.9%), bevacizumab (37.4%), ranibizumab (7.9%), dexamethasone intravitreal implant (6.8%), brolucizumab (2.7%), and triamcinolone acetonide (2.3%) (Table 2). Days between injection and urgent follow-up was on average 3.96 ± 2.14 days. Urgent follow-ups included blurred vision in 164 patients (37.2% of urgent visits), flashes, floaters or posterior vitreous detachment (PVD) in 55 (12.5%), pain in 42 (9.5%), 43 (9.8%) corneal abrasions, 33 (7.5%) subconjunctival hemorrhages, corneal dryness or foreign body sensation in 30 (6.6%), endophthalmitis in 20 (4.5%), 18 (4.1%)vitreous hemorrhages, iritis or uveitis in 11 (2.5%), miscellaneous complications in 9 (2.0%), 7 (1.6%) elevated intraocular pressures, choroidal neovascular membrane in 4 (0.9%), 4 (0.9%) retinal detachments or tears, and 2 (0.45%) traumatic cataracts (Table 3).

CONCLUSION

IVIs resulted in 0.60% urgent/unscheduled follow-up visits within 7 days of injection. Most common causes were blurred vision and symptoms of PVD.

Safety of Receiving Anti-Vascular Endothelial Growth Factor Intravitreal Injection in Office-Based vs Operating Room Settings: A Meta-analysis

Importance

Compared with the operating room (OR), office-based intravitreal injection (IVI) is considered a more cost-effective and convenient approach, yet clinical outcomes of IVIs with anti-vascular endothelial growth factor (VEGF) agents in different settings (office-based vs OR) have not been systematically evaluated.

Objective

To evaluate the safety outcomes of IVI with anti-VEGF agents in the OR vs office-based setting.

Data Sources

PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov were searched from inception to July 2020.

Study Selection

Eligible studies reporting on patients who received IVIs with anti-VEGF drugs with a clearly stated injection setting of the office or OR.

Data Extraction and Synthesis

Two reviewers independently screened studies, extracted data, and assessed risk of bias. A meta-analysis was conducted to determine the rates of endophthalmitis (EO) and culture-positive EO.

Main Outcomes and Measures

Rates of EO and culture-positive EO following anti-VEGF IVIs in the OR and office-based setting.

Results

Thirty-one studies with a total of 1 275 815 injections were included. Comparative analysis suggested no difference between rates of EO after IVIs performed in the office and OR settings (odds ratio, 3.06; 95% CI, 0.07-139.75; P = .57; I2 = 80%) were identified, yet a higher rate of culture-positive EO was found in the office setting (odds ratio, 21.52; 95% CI, 2.39-193.55; P = .006; I2 = 0%). The pooled rates of EO following anti-VEGF IVIs were 0.03% (95% CI, 0.03-0.04) and 0.02% (95% CI, 0.01-0.04) in office and OR settings, respectively, and the pooled rates of culture-positive EO were 0.01% (95% CI, 0.01-0.02) and 0.01% (95% CI, 0-0.02). The pooled rates of other ocular and systemic adverse events were low.

Conclusions and Relevance

The rate of clinically suspected or culture-positive EO following anti-VEGF IVIs was low whether the procedure was performed in the office or OR setting. Bacterial spectrum could differ between the 2 settings. This meta-analysis could not determine if it is more appropriate to give treatment in the OR for safety reasons in low-income compared with higher-income regions in the world.

Intravitreal Injection Therapy: Current Techniques and Supplemental Services

Purpose:

Intravitreal injection is the most frequently performed eye procedure in the world and is an essential component in the management of sight-threating retinal diseases and conditions. Given the seriousness and range of diseases treated and the risks of the procedure, retina specialists must weigh the pros and cons of each individual treatment. Complexities guiding injection treatment are multifaceted and involve patient-history review, careful examination, diagnostic testing selection and interpretation, customized medical decision-making, and follow-up considerations.

Methods:

This article by the Intravitreal Injection Task Force Committee of the American Society of Retina Specialists documents the intricacies and necessary components of the intravitreal injection procedure.

Results:

By expert consensus, the task force further recommends ancillary services and decision-making that may accompany intravitreal injection visits, when appropriate, to monitor response to treatment, adjust treatment, and manage additional considerations in the same or fellow eye.

Conclusions:

Retina specialists can optimize safety and therapeutic outcomes with individualized consideration and customization of intravitreal injection treatment for each patient.

Effects of intravitreal injection of siRNA against caspase-2 on retinal and optic nerve degeneration in air blast induced ocular trauma

Ocular repeated air blast injuries occur from low overpressure blast wave exposure, which are often repeated and in quick succession. We have shown that caspase-2 caused the death of retinal ganglion cells (RGC) after blunt ocular trauma. Here, we investigated if caspase-2 also mediates RGC apoptosis in a mouse model of air blast induced indirect traumatic optic neuropathy (b-ITON). C57BL/6 mice were exposed to repeated blasts of overpressure air (3 × 2 × 15 psi) and intravitreal injections of siRNA against caspase-2 (siCASP2) or against a control enhanced green fluorescent protein (siEGFP) at either 5 h after the first 2 × 15 psi ("post-blast") or 48 h before the first blast exposure ("pre-blast") and repeated every 7 days. RGC counts were unaffected by the b-ITON or intravitreal injections, despite increased degenerating ON axons, even in siCASP2 "post-blast" injection groups. Degenerating ON axons remained at sham levels after b-ITON and intravitreal siCASP2 "pre-blast" injections, but with less degenerating axons in siCASP2 compared to siEGFP-treated eyes. Intravitreal injections "post-blast" caused greater vitreous inflammation, potentiated by siCASP2, with less in "pre-blast" injected eyes, which was abrogated by siCASP2. We conclude that intravitreal injection timing after ocular trauma induced variable retinal and ON pathology, undermining our candidate neuroprotective therapy, siCASP2.

The Challenges of Treating Neovascular Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is one of the main causes of visual impairment and blindness in patients over 60 years in developed countries. Whilst no effective form of therapy is available for the dry form of AMD, intravitreal application of anti-VEGF substances is able to prevent the progression of neovascular AMD (nAMD) in most cases. Aside from the drugs ranibizumab, aflibercept and brolucizumab, other agents such as bevacizumab are often used off-label in order to save expense. The treatment intervals have also been refined, so as to reduce the burden on patients and health care systems. After fixed injection intervals, the pro re nata-regimen has been developed. Each month, it is decided whether the patient receives intravitreal injections based on fixed criteria. In the treat and extend-protocol, patients receive injections on each visit, but the intervals between injections vary due to the clinical outcomes. The observe-and-plan regime allows scheduling of the injection intervals in blocks, for three consecutive injections at a time. However, results of real-world studies were not able to reproduce those obtained in the pivotal studies. A high number of visits and fear of the injection procedure impose a burden on patients, that is mostly accepted due to fear of vision loss. Caregivers also complain of loss of productivity and income from having to provide regular support to patients. Health care systems worldwide are affected by increasing treatment numbers and the costs involved. The treatment of nAMD constitutes an achievement for modern medicine. However, despite the challenges, it must be evaluated and reviewed repeatedly in order to provide the best therapy for patients.

Posterior cyclodialysis cleft following intravitreal injection

Purpose

To describe an unusual complication of an intravitreal injection.

Observation

Here, we report a case of hypotony following an intravitreal injection due to a posterior cyclodialysis cleft and describe its management and resolution.

Conclusions

Posterior cyclodialysis clefts are a rare cause of hypotony following intravitreal injection. Posterior clefts may not be visualized by conventional gonioscopy. Ultrasound biomicroscopy may be useful in aiding diagnosis.

Importance

This report highlights a rare cause of hypotony following intravitreal injection and illustrates the importance of adjunctive imaging for accurate diagnosis.

Emerging biological therapies for the treatment of age-related macular degeneration

INTRODUCTION

Age-related macular degeneration (AMD) is the leading cause of blindness in individuals over age 50 in developed countries. Current therapy for nonexudative AMD (neAMD) is aimed at modifying risk factors and vitamin supplementation to slow progression, while intravitreal anti-vascular endothelial factor (VEGF) injections are the mainstay for treatment of choroidal neovascularization in exudative AMD (eAMD).

AREAS COVERED

Over the past decade, promising therapies have emerged that aim to improve the current standard of care for both diseases. Clinical trials for neAMD are investigating targets in the complement cascade, vitamin A metabolism, metformin, and tetracycline, whereas clinical trials for eAMD are aiming to decrease treatment burden through novel port delivery systems, increasing drug half-life, and targeting new sites of the VEGF cascade. Stem cell and gene therapy are also being evaluated for treatment of neAMD and eAMD.

EXPERT OPINION

With an aging population, the need for effective, long term, low burden treatment options for AMD will be in increasingly high demand. Current investigations aim to address the shortcomings of current treatment options with breakthrough treatment approaches. Therapeutics in the pipeline hold promise for improving the treatment of AMD, and are on track for widespread use within the next decade.