Evolving guidelines for intravitreous injections

Potential Risk Factors for Ocular Pain in Patients Undergoing Multiple Intravitreal Injections of Anti-Vascular Endothelial Growth Factor

Purpose

To assess ocular pain in patients undergoing multiple intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) who have previous factors that may influence pain sensitivity.

Methodology

This is a prospective, observational, case series study involving patients who underwent multiple (≥3) pro re nata intravitreal injections of ranibizumab or aflibercept to treat any cause of chorioretinal vascular disease. Ocular pain was assessed by the numerical analog scale during intravitreal injection. For this study, the main variable was ocular pain and the secondary variables included age, sex, previous history of glaucoma, primary retinal vascular disease, severe dry eye history, trigeminal pain, scleral buckle surgery, collagen diseases, fibromyalgia, severe migraine history, pars plana vitrectomy, scleral thickness measurements, and type of anti-VEGF.

Results

In a total of 894 patients, 948 eyes (4822 intravitreal injections), 793 patients (88.6%) had ocular pain sensitivity between no pain to mild pain, 80 patients (8.9%) had moderate ocular pain, 15 patients (1.6%) had severe ocular pain, and 6 patients (0.7%) had extremely severe ocular pain. Patients with severe dry eye (p = 0.01) and previous history of scleral buckle surgery (p = 0.01) showed a significant correlation with ocular pain during intravitreal injection. Pars plana scleral thickness (>550 um) and diabetic neuropathy were associated with ocular pain but did not meet the criteria for statistical significance (p = 0.09 and p = 0.06, respectively).

Conclusion

Dry eye and prior scleral buckle surgery may contribute to pain associated with intravitreal injection. These issues should be taken into consideration in patients undergoing multiple intravitreal injections.

METHOD OF POVIDONE-IODINE APPLICATION AND ENDOPHTHALMITIS RISK

PURPOSE

To evaluate the proportion of patients developing endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor agents according to the mode of povidone-iodine (PI) antisepsis.

METHODS

A retrospective review of the anti-vascular endothelial growth factor injections given in a 7-year period at a community-based retinal practice. Endophthalmitis was diagnosed to have occurred if an eye developed intraocular inflammation and was given antibiotics with or without supportive culture identification of an organism. As part of their habitual clinical practice, component physicians used 5% PI as two drops, one drop, or just a dot of PI administered with a cotton-tipped applicator to the site before injection.

RESULTS

There were 113,610 intravitreal injections administered and 23 cases were diagnosed with endophthalmitis over the 7-year period, for a rate of 1 case per 4,940 injections. The mode of PI antisepsis showed no significant relation to the rate of endophthalmitis ( P = 0.55, chi-square test). The proportion of endophthalmitis by physician demonstrated no significant difference ( P = 0.39, chi-square test).

CONCLUSION

The use of PI has been associated with decreased incidence of endophthalmitis, but the mode of application has not been standardized. The results of this study suggest that "more is not better" in PI antisepsis in endophthalmitis. Moreover, the toxicity of PI on the ocular surface is known to be dose-related.

Multi-modal transducer-waveguide construct coupled to a medical needle

Annually, more than 16 × 109 medical needles are consumed worldwide. However, the functions of the medical needle are still limited mainly to cutting and delivering material to or from a target site. Ultrasound combined with a hypodermic needle could add value to many medical applications, for example, by reducing the penetration force needed during the intervention, adding precision by limiting the needle deflection upon insertion into soft tissues, and even improving tissue collection in fine-needle biopsy applications. In this study, we develop a waveguide construct able to operate a longitudinal-flexural conversion of a wave when transmitted from a Langevin transducer to a conventional medical needle, while maintaining high electric-to-acoustic power efficiency. The optimization of the waveguide structure was realized in silico using the finite element method followed by prototyping the construct and characterizing it experimentally. The experiments conducted at low electrical power consumption (under 5 W) show a 30 kHz flexural needle tip displacement up to 200 μm and 73% electric-to-acoustic power efficiency. This, associated with a small sized transducer, could facilitate the design of ultrasonic medical needles, enabling portability, batterization, and improved electrical safety, for applications such as biopsy, drug and gene delivery, and minimally invasive interventions.

A quantitative sonoelastography evaluation of ocular and periocular elasticity after intravitreal ranibizumab injection

PURPOSE

We evaluated changes in ocular and periocular elasticity by ultrasound (US) elastography in intravitreal ranibizumab-treated eyes and the healthy fellow eyes of patients with neovascular AMD.

METHODS

The study was performed on 52 eyes of 26 volunteers who ranged in age from 59 to 89 (mean 72±7.78) years old. The study group consisted of the patients with neovascular AMD treated with intravitreal ranibizumab. The fellow eyes (without choroidal neovascularization) of the study group were selected as the control group. All patients were examined with sonoelastography before intravitreal injection and at 1day, 1week, and 1month after intravitreal injection. All images were acquired with a Toshiba Aplio 500 ultrasound system (Tokyo, Japan) including software with a combined autocorrelation method and a multifrequency linear probe. The elastography values of the anterior vitreous (AV), posterior vitreous (PV), retina-choroid-sclera complex (RCS), retrobulbar fat tissue (RF), optic nerve head (ONH) and retrobulbar optic nerve (RON) were measured in each eye.

RESULTS

There were 13 male (50%) and 13 female (50%) participants in our study. Anterior vitreous, posterior vitreous, RCS, retrobulbar fat tissue, ONH, and RON US elastography values were similar in both groups (P˃0.05 for all). On the other hand, there was a positive correlation between the difference between baseline and 1-month PV sonoelastography values and age (r=0.47, P=0.035).

CONCLUSION

A single dose intravitreal Ranibizumab (Lucentis®, Genentech, USA) injection does not alter the elasticity of ocular and periocular structures.

Bacterial endophthalmitis following anti-VEGF intravitreal injections: a retrospective case series

BACKGROUND

To describe the incidence of endophthalmitis and the treatment outcomes of acute bacterial endophthalmitis following intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections in a Brazilian hospital. The analysis was based on the timing of infection after intravitreal injection, culture results, visual acuity, and the presence of epiretinal membrane after a 1-year follow-up period, spanning nine years.

METHODS

This retrospective case series, conducted over a 9-year period, aimed to evaluate the treatment outcomes of acute endophthalmitis following intravitreal Bevacizumab injections. The inclusion criteria involved a chart review of 25 patients who presented clinical signs of acute endophthalmitis out of a total of 12,441 injections administered between January 2011 and December 2019. Negative culture results of vitreous samples or incomplete data were excluded. Ultimately, 23 patients were enrolled in the study. Eight patients were treated with intravitreal antibiotic injections (IVAI) using vancomycin 1.0 mg/0.05mL and ceftazidime 2.25 mg/0.05mL, while 15 patients underwent pars plana vitrectomy (PPV) followed by intravitreal antibiotic injections at the end of surgery (IVAIES). The main outcome measures were the efficacy of controlling the infection with IVAI as a standalone therapy compared to early PPV followed by IVAIES. Data collected included pre-infection and one-year post-treatment best corrected visual acuity (BCVA), optical coherence tomography (OCT) abnormalities, and enucleation/evisceration rates. To compare groups, Mann-Whitney and ANOVA tests were employed for statistical analysis.

RESULTS

The incidence rate of bacterial endophthalmitis was 0.185% (1/541 anti-VEGF injections), with the highest infection rates observed in 2014 and 2017. Patients presented clinical symptoms between 2 and 7 days after injection. The most common isolated organisms were coagulase-negative Staphylococci and Streptococci spp. Treatment outcomes showed that both IVAI and PPV + IVAIES effectively controlled the infection and prevented globe atrophy. After one year, the PPV group with BCVA better than Light Perception had a significantly better BCVA compared to the IVAI group (p 0.003). However, PPV group had higher incidence of epiretinal membranes formation compared to the IVAI group. (P 0.035) CONCLUSION: Anti-VEGF injections carry a risk of developing acute bacterial endophthalmitis. Isolated antibiotic therapy could be an effective treatment to control the infection, but performing PPV + IVAIES as a primary treatment showed promising results in terms of improving BCVA after one year, despite a higher rate of epiretinal membrane formation. Further studies are needed to confirm these findings.

Dropped nucleus postintravitreal injection with intact anterior capsule: a case report

The aim was to describe a case of inadvertent posteriorly dislocated lens nucleus after intravitreal injection (IVI) for diabetic retinopathy, highlighting the importance of adherence to the standard protocol of IVI.

Case presentation

A 58-year-old female with uncontrolled type 2 diabetes mellitus presented with decreased vision bilaterally. At presentation, the anterior segment of both eyes showed nuclear sclerosis +2. Fundus examination of the left eye was not visible due to diffuse vitreous hemorrhage, for which an intravitreal ranibizumab injection was given. She presented for follow-up 3 weeks later; an aphakic left eye was discovered during the examination. A dropped nucleus was diagnosed, and the patient underwent an uneventful pars plana vitrectomy with removal of the dropped nucleus and implantation of a sulcus three-piece intraocular lens. Postoperatively, the vision had improved from hand motion to 6/18. Clinical discussion: this case presentation reports an unusual complication of a dropped lens nucleus after IVI. It highlights the possibility of inadvertent lens trauma in such a procedure and the importance of proper adherence to standards to avoid such a complication.

Conclusion

This rare complication highlights the importance of carefully following IVI guidelines in the hands of experienced ophthalmologists and the need for meticulous supervision for ophthalmology residents because it is not a risk-free procedure.

Computational Modeling of Ophthalmic Procedures: Computational Modeling of Ophthalmic Procedures

PURPOSE

To explore how finite-element calculations can continue to contribute to diverse problems in ophthalmology and vision science, we describe our recent work on modeling the force on the peripheral retina in intravitreal injections and how that force increases with shorter, smaller gauge needles. We also present a calculation that determines the location and stress on a retinal pigment epithelial detachment during an intravitreal injection, the possibility that stress induced by the injection can lead to a tear of the retinal pigment epithelium.

BACKGROUND

Advanced computational models can provide a critical insight into the underlying physics in many surgical procedures, which may not be intuitive.

METHODS

The simulations were implemented using COMSOL Multiphysics. We compared the monkey retinal adhesive force of 18 Pa with the results of this study to quantify the maximum retinal stress that occurs during intravitreal injections.

CONCLUSIONS

Currently used 30-gauge needles produce stress on the retina during intravitreal injections that is only slightly below the limit that can create retinal tears. As retina specialists attempt to use smaller needles, the risk of complications may increase. In addition, we find that during an intravitreal injection, the stress on the retina in a pigment epithelial detachment occurs at the edge of the detachment (found clinically), and the stress is sufficient to tear the retina. These findings may guide physicians in future clinical research. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Long-acting ocular drug delivery technologies with clinical precedent

INTRODUCTION

Ocular long-acting injectables and implants (LAIIs) deliver drug at a controlled release rate over weeks to years. A reduced dose frequency eases the treatment burden on patients, minimizes the potential for treatment-related adverse effects, and improves treatment adherence and persistence.

AREAS COVERED

This review provides a comprehensive landscape of ocular LAII drug delivery technologies with clinical precedent, including eight commercial products and 27 clinical programs. Analysis of this landscape, and the specific technologies with the greatest precedent, provides instructive lessons for researchers interested in this space and insights into the direction of the field.

EXPERT OPINION

Further technological advancement is required to create biodegradable LAIIs with extended release durations and LAIIs that are compatible with a broader array of therapeutic modalities. In the future, ocular LAII innovations can be applied to diseases with limited treatment options, prophylactic treatment at earlier stages of disease, and cost-effective treatment of ocular diseases in global health settings.

Appropriate dose of intravitreal ranibizumab for ROP: a retrospective study

Objective

To compare the recurrence rate of retinopathy of prematurity (ROP) after treatment with 0.3 mg vs. 0.25 mg ranibizumab.

Subjects

All patients with ROP who underwent intravitreal injection of ranibizumab in Hainan General Hospital between January 2014 and May 2020 were included in this retrospective study.

Methods

Eighty-two cases (146 eyes) who received intravitreal injection of 0.25 mg ranibizumab were included in the conventional-dose group, and 59 cases (108 eyes) who received intravitreal injection of 0.3 mg ranibizumab were included in the high-dose group. The two groups were further divided into the 25-28-week, 29-31-week, 32-34-week, and 35-36-week GA subgroups. The differences between the conventional-dose group and the high-dose group in gestational age (GA), birth weight (BW), age at initial injection (weeks), incidence of systemic diseases, the recurrence rate of ROP, and age at retinal vascularization completed (weeks) were analyzed.

Results

GA, BW, age at initial injection, and the incidence of systemic diseases were not significantly different between the conventional-dose group and the high-dose group (p > 0.05). The recurrence rates of ROP were significantly lower in the 25-28-week, 29-31-week, and 32-34-week subgroups of the high-dose group than in the same subgroups of the conventional-dose group (p < 0.05). Within the conventional-dose group, the recurrence rate of ROP was significantly lower in the 32-34-week and 35-36-week subgroups than in the 25-28-week and 29-31-week subgroups (p < 0.05). Within the high-dose group, the recurrence rate of ROP was not significantly different between the four subgroups (p > 0.05). Retinal vascularization was completed at a later age in the 32-34-week subgroup of the high-dose group than in the 32-34-week subgroup of the conventional-dose group (p < 0.05) but was not significantly different between the two groups at any other GA range (p > 0.05). No severe ocular or systemic complications occurred in any patient.

Conclusion

Treatment with 0.3 mg ranibizumab can reduce the recurrence rate of ROP without prolonging retinal vascularization or causing serious systemic complications. Therefore, this dose may be an appropriate therapeutic dose for ROP.

Management Patterns and Outcomes for Intravitreal Injection–Related Endophthalmitis

Purpose:

This work describes the clinical management and outcomes in cases of presumed infectious endophthalmitis following intravitreal injection at a tertiary academic medical center.

Methods:

A retrospective review took place of eyes that presented to the Duke Eye Center over a 9-year period and were diagnosed with intravitreal injection–related endophthalmitis. Clinical presentation, management, microbiologic yield, visual outcomes, and complications were abstracted from medical records.

Results:

Of 23 eyes diagnosed with postinjection endophthalmitis, 52.2% underwent anterior chamber tap (33.3% of which first underwent dry needle vitreous tap), 47.8% underwent needle vitreous tap, 17.4% underwent neither, and none underwent pars plana vitrectomy (PPV) for initial management. Subsequent PPV was performed in 6 eyes (26.1%). Mean visual acuity (VA) improved by 50 Early Treatment Diabetic Retinopathy Study letters at 6 months. Eyes that underwent initial anterior chamber tap had worse presenting VA than those that did not ( P = .01). Eyes undergoing subsequent PPV had worse VA at presentation ( P = .02) and at 6 months ( P < .001). Eyes presenting with VA of hand motion (20/8000) or worse were more likely to undergo subsequent PPV ( P = .02).

Conclusions:

Eyes with intravitreal injection–related endophthalmitis presenting with VA of hand motion or worse were more likely to undergo subsequent PPV. Future studies with larger cohorts may reveal whether earlier vitrectomy should be considered in these patients.

Treatment outcomes of acute poptoperative infectious endophthalmitis

Background

Acute postoperative endophthalmitis is one of the most severe complications of modern ophthalmic procedures including cataract surgeries, vitrectomy and intravitreal injection (IVI). We evaluated the treatment outcomes of acute postoperative infectious endophthalmitis.

Methods

In this retrospective study, we collected data from 82 patients with acute infectious endophthalmitis within 6 weeks after intraocular surgeries, including cataract surgeries, vitreoretinal surgeries, and IVI, from January 2010 to December 2019. We analyzed the pre-treatment, treatment-related and post-treatment factors that affected visual outcomes.

Results

The mean age was 67.65 ± 9.52 years, the proportion of male patients was 56.1%. The mean baseline vision was 1.92 (Snellen Equivalent SE], counting finger [CF]) ± 0.54 logarithm of the minimum angle of resolution (log MAR) and the mean final vision was 0.71 (SE, 39/200) ± 0.80 logMAR. Visual improvement was significant (P < 0.001). The pre-treatment factors affecting final visual outcomes were diabetes, hemodialysis, baseline vision, signs of vitreous opacity, and different surgeries before endophthalmitis; the treatment-related factors affecting visual outcomes were the choice factors between IVI of antibiotics alone and vitrectomy combined with IVI of antibiotics, and the injection numbers of antibiotics; post-treatment factors affecting visual outcomes were complications such as retinal detachment (RD), glaucoma and macular pucker. Furthermore, prior cataract surgery was associated with a better mean final vision of 0.57 (SE, 54/200) ± 0.67 logMAR while prior vitrectomy resulted in the worst mean final vision of 1.38 (SE, 21/500) ± 0.75 logMAR.

Conclusions

The important factors that affected the final visual prognosis, included diabetes, hemodialysis, baseline vision, severity of vitritis, treatment strategies and complications. The treatment outcomes revealed better final vision in prior cataract surgery than vitrectomy.

Silicone oil droplets in the vitreous after intravitreal injections: review of literature with clinical examples

Currently, intravitreal injections are firmly in the lead as a drug delivery method for treatment of a wide range of eye diseases. With the accumulation of clinical material, knowledge about the complications and side effects of this technique is expanding. One of the undesirable phenomena that has been actively studied recently is the ingress of silicone oil droplets from single-use syringes and needles used to perform the procedure into the vitreous cavity of patients eyes. The analysis of the results of original studies on this issue is carried out, and the currently available practical recommendations aimed at reducing the risk of this complication are presented. The article is illustrated with original clinical examples. It can be concluded that the penetration of silicone oil into the eye cavity during intravitreal injections is an urgent problem of modern ophthalmology that requires further investigation and solution.

Application of Nanomaterials in the Treatment and Diagnosis of Ophthalmology Diseases

Eye diseases often lead to impaired vision and seriously affect the daily life of patients. Local administration of ophthalmic drugs is one of the most important approaches for the treatment of ophthalmic diseases. However, due to the special biochemical environment of the ocular tissue and the existence of many barriers, the bioavailability of conventional ophthalmic preparations in the eye is very low. Nanomaterials can be utilized as carriers of drugs, which can improve the absorption, distribution, metabolism and bioavailability of drugs in eyes. Nanomaterials have also the advantages of small size, simple preparation, good degradability, strong targeting, and little stimulation to biological tissues, providing an innovative and practical method for the drug delivery of ophthalmic diseases. In addition, nanomaterials can be used as an auxiliary means for early diagnosis of ophthalmic diseases by improving the specificity and accuracy of detection methods. Nanomaterials help clinicians and researchers delve deeper into the physiology and pathology of the eye at the nanoscale. We summarize the application of nanomaterials in the diagnosis and treatment of ophthalmic diseases in this review.

Efficacy of anti-vascular endothelial growth factor agents for treating neovascular age-related macular degeneration in vitrectomized eyes

PURPOSE

To evaluate the efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents for treatment of neovascular age-related macular degeneration (nAMD) in vitrectomized eyes.

METHODS

The medical records were reviewed of nAMD patients treated with anti-VEGF agents who previously underwent pars plana vitrectomy (PPV). PPV was performed with complete posterior vitreous detachment induction.

RESULTS

A total of 44 eyes from 44 patients were included. The mean central foveal thickness (CFT) was 478.50 ± 156.93 μm at baseline, 414.25 ± 143.55 μm (86.6% of baseline) at 1 month after first injection (P < 0.001), and 386.75 ± 141.45 μm (80.8% of baseline) after monthly multiple injections (2.30 ± 1.07; range, 1-5) (P < 0.001). The mean logarithm of the minimum angle of resolution best-corrected visual acuity visual acuity (BCVA) was 0.85 ± 0.57 at baseline, 0.86 ± 0.63 after the first injection, and 0.84 ± 0.64 after monthly multiple injections. BCVA improved in 39.5% at 1 month after first injection and 45.2% at 1 month after monthly multiple injections. In the subgroup analysis, CFT of eyes with the posterior capsule decreased significantly to 85.8% and 79.8% of baseline values at 1 month after the first injection and after monthly multiple injections, respectively. CFT of eyes without the posterior capsule decreased to 91.6% and 87.4% of baseline values at 1 month after the first injection and after monthly multiple injections, respectively, without statistical significance.

CONCLUSION

Monthly injections of Intravitreal anti-VEGF agents induced favorable anatomical improvement and vision maintenance in vitrectomized eyes with nAMD.

All India Ophthalmological Society members' survey: Practice pattern of intravitreal anti-vascular endothelial growth factor injection

Purpose:

The aim of this paper is to report the results of an on-line survey to evaluate the practice pattern of Indian retina specialists in administering intravitreal anti-vascular endothelial growth factor injection.

Methods:

A structured questionnaire on the intravitreal injection (IVI) procedure protocols was sent online to all members of the All India Ophthalmological Society (AIOS) with a request to the retina specialists to respond. A unique link that directed to the web-based questionnaire page allowed a single response only. Participating physicians were masked from each others' responses. The responses were categorized into pre-injection patient preparation, injection aliquoting, injection administration, and post-injection care. The results were compared with similar surveys in Europe, the UK, and the USA.

Results:

Response was received from 741 of 1016 (73%) retina specialists (of 16,000 AIOS ophthalmologists). The survey showed: 43.5% evaluated patient's cardiac risk factors, 60% used prophylactic topical antibiotic, 90.9% performed injection under topical anesthesia, 55% aliquoted from the bevacizumab vial at the eye care facility, 66.2% used a single puncture technique, 91.4% injected in the main operating room, 98% wore masks and sterile gloves during the procedure, 96% used lid speculum, and 89.3% advised topical antibiotic after the procedure. Peri procedure antibiotic use, injection in the min operating room, wearing of gloves and mask were higher than practices in other countries.

Conclusion:

Ophthalmologists in India practice asepsis in IVI procedure. There is no uniform protocol for aliquoting bevacizumab. Single use bevacizumab vial for exclusive ophthalmic use will further improve the safety of the procedure.

Latanoprost-loaded phytantriol cubosomes for the treatment of glaucoma

Glaucoma is a degenerative optic neuropathy characterized by increased intraocular pressure that if untreated can result in blindness. Ophthalmological drug therapy is a challenge of great clinical importance due to the diversity of ocular biological barriers which commonly causes limited or no effectiveness for drugs delivered through the eye. In this work, we proposed the development of nanosized cubic liquid crystals (cubosomes) as a new drug carrier system for latanoprost, an anti-glaucoma drug. Latanoprost-loaded phytantriol cubosomes (CubLnp) were prepared using a top-down method. Latanoprost concentration in the formulations ranged from 0.00125% to 0.02% w/v. All cubosomes displayed an average size around 200 nm, a low polydispersity index of 0.1 and zeta potential values around -25 mV, with an encapsulation efficiency of about 90%. Structural studies revealed that cubosomes displayed a double-diamond surface, Pn3m cubic-phase structure, and was not affected by drug loading. Calorimetric studies revealed a fast and exothermic interaction between latanoprost and cubosomes. According to in vitro essays, latanoprost release from cubosomes was slow in time, evidencing a sustained release profile. Based on this behavior, the in vivo hypotensive intraocular effect was evaluated by means of the subconjunctival administration of CubLnp in normotensive rabbits. We obtained promising results in comparison with a marketed latanoprost formulation (0.005% w/v).

Survey of Intravitreal Injection Techniques Among Retina Specialists in Mexico

Purpose

To report technique preferences for intravitreal injections among retina specialists in Mexico.

Methods

Cross-sectional survey. Ophthalmologists with a two-year retina training, active members of the Mexican Retina Association, were contacted through email to answer a survey consisting of 37 items regarding their IVI application technique.

Results

A total of 133 retina specialists participated, with a response rate of 78%. Forty-five percent applied the intravitreal injections in an operating room designated for the procedure. Sixty-three percent reported never injecting both eyes on the same day. Ninety-six percent wore a face mask during the procedure and 91% wore gloves. Eighty-two percent used a lid speculum. Tetracaine drops were the anesthetic method employed by 97% of participants. All participants utilized povidone-iodine for antisepsis. Eighty percent measured the puncture site with a caliper. Superotemporal quadrant was the one chosen to place the injection by 63% of participants. Fifty-nine percent indicated post-injection antibiotic drops for several days. Post-injection counting fingers visual acuity was verified by 53% of the participants. Fifty-six percent of the participants placed an eye-patch after the procedure.

Conclusion

There are different practices regarding the application of intravitreal injections among retina specialists in Mexico. Performing this type of survey periodically could show changes in preferences, as new evidence is incorporated into clinical practice.

DILUTE POVIDONE-IODINE PROPHYLAXIS MAINTAINS SAFETY WHILE IMPROVING PATIENT COMFORT AFTER INTRAVITREAL INJECTIONS

PURPOSE

To report the rates of postintravitreal injection (IVT) endophthalmitis with topical conjunctival application of various concentrations of povidone-iodine (PI), including no PI.

METHODS

Retrospective chart review of patients receiving IVTs performed in a single practice between January 2011 and June 2016. Concentration of PI for all injections was recorded and cases of endophthalmitis identified and reviewed.

RESULTS

A total of 35,060 IVTs in 1854 patients were included from the 5.5-year period. 29,281 injections were performed with standard 5% PI, 5,460 injections with diluted PI (3,731 with 2.5%, 1,673 with 1.25%, 56 with 0.625%), and 319 IVTs with no PI. Incidence of patient-reported PI sensitivity occurred in 15.9% of patients. Fourteen cases of endophthalmitis were identified: 12 in eyes that received 5% PI, one in an eye that received 1.25% PI, and one in an eye receiving no PI. The incidence of endophthalmitis was 0.04% for 5% PI, 0.02% for dilute PI, and 0.31% for no PI prophylaxis. All cases underwent prompt vitrectomy and had positive cultures for coagulase-negative Staphylococcus.

CONCLUSION

Application of dilute PI solution to the conjunctiva at the time of IVT is an effective alternative to 5% PI for endophthalmitis prophylaxis in betadine-sensitive patients.

Effect of Paracentesis on Retinal Function Associated With Changes in Intraocular Pressure Caused by Intravitreal Injections

Purpose

Intravitreal injections of antivascular endothelial growth factor agents are widely performed, and subsequent intraocular pressure increase may cause retinal nerve fiber damage. This study aimed to determine the effects of paracentesis before intravitreal injection of an antivascular endothelial growth factor on electroretinograms.

Methods

This was a retrospective observational study in a university hospital. Twenty-five eyes of 25 patients who underwent intravitreal injections of antivascular endothelial growth factor agents were selected for evaluation. Intraocular pressures and electroretinograms were recorded before surgery (baseline), after anterior chamber paracentesis, and after intravitreal injection. The amplitudes and latencies of the a- and b-waves, photopic negative response, and oscillatory potential were measured. Changes in each component of the electroretinograms, intraocular pressure, and relationships between these two factors were investigated. The preoperative and postoperative ocular perfusion pressure was calculated based on blood pressure.

Results

The amplitudes of the b-waves were significantly smaller after intravitreal injection than at baseline (P = 0.02), while no significant change was found in the other components during surgery. There were no significant changes in the latencies of any component during surgery. The intraocular pressure was significantly lower (P < 0.001) after anterior chamber paracentesis (6.8 ± 4.3 mm Hg) compared to baseline (24.1 ± 8.1 mm Hg) or after intravitreal injection (17.1 ± 9.6 mm Hg; P < 0.001).

Conclusions

Performing anterior chamber paracentesis before an intravitreal injection can prevent the intraocular pressure elevation and thus minimize the electrophysiological retinal dysfunction.

Translational Relevance

Anterior chamber paracentesis before an intravitreal injection mitigates the adverse effects on retinal function.

Survey of Intravitreal Injection Practice Patterns Among Retina Specialists

Purpose:

Intravitreal injection therapy (IVT) is the most performed procedure in ophthalmology. This study was conducted to determine current trends in IVT delivery.

Methods:

An online, 31-question, multiple-choice survey was sent to 1677 retina specialists. The survey consisted of 3 sections: general questions, procedure technique, and postprocedure technique.

Results:

A total of 264 (16%) retina specialists completed the survey. The use of povidone-iodine (100%) and small-gauge needles (97%) was common, whereas ocular anesthesia was split among lidocaine gel (31%), lidocaine drops (25%), subconjunctival lidocaine (28%), and lidocaine-soaked pledgets (15%). More than 85% indicated povidone-iodine contributes to post-IVT corneal toxicity, and 12% reported that a needlestick injury to physician or staff occurred during IVT.

Conclusions:

Key areas for IVT improvement include optimized ocular anesthesia, development of a guarded needle for ocular drug delivery, and formulation of a less toxic ocular antiseptic.

Critical analysis of techniques and materials used in devices, syringes, and needles used for intravitreal injections

Intravitreal injections have become the most commonly performed intraocular treatments worldwide. Because intravitreal injections may induce severe adverse events, such as infectious and noninfectious endophthalmitis, cataract, ocular hypertension, vitreous hemorrhage, or retinal detachment, appropriate awareness of the materials and techniques used are essential to reduce these sight-threatening complications. This review provides insights into the needles, syringes, silicone oil coating, sterilization methods, devices to assist intravitreal injections, scleral piercing techniques using needles, syringe handling, anesthesia, and safety issues related to materials and techniques. It is paramount that physicians be aware of every step involved in intravitreal injections and consider the roles and implications of all materials and techniques used. The ability to understand the theoretical and practical circumstances may definitely lead to state-of-the-art treatments delivered to patients. The most important practical recommendations are: choosing syringes with as little silicone oil as possible, or, preferably, none; avoiding agitation of syringes; awareness that most biologics (e.g., antiangiogenic proteins) are susceptible to changes in molecular properties under some conditions, such as agitation and temperature variation; understanding that improper materials and techniques may lead to complications after intravitreal injections, e.g., inflammation; and recognizing that some devices may contribute to an enhanced, safer, and faster intravitreal injection technique.

Ghost cell glaucoma after intravitreous injection of ranibizumab in proliferative diabetic retinopathy

Background

The development of ghost cell glaucoma in patients with proliferative diabetic retinopathy (PDR) after intravitreous injection (IV) was rare. Here we reported a series of patients with PDR who received Intravitreous Ranibizumab (IVR) and developed ghost cell glaucoma and analyzed the potential factors that might be related to the development of ghost cell glaucoma.

Methods

Retrospective case series study. The medical records of 71 consecutive eyes of 68 PDR patients who received vitrectomy after IVR from January 2015 to January 2017 were reviewed. The development of ghost cell glaucoma after IVR was recorded. Characteristics of enrolled patients were retrieved from their medical charts. Factors associated with ghost cell glaucoma were compared between eyes with the development of ghost cell glaucoma and eyes without the development of ghost cell glaucoma. Variables were further enrolled in a binary backward stepwise logistic regression model, and the model that had the lowest AIC was chosen.

Results

There were 8 out of 71 eyes of the PDR patients developed ghost cell glaucoma after they received IVR. The interval between detection of elevation of intraocular pressure (IOP) and IV ranged from 0 to 2 days. Among them, after IVR, there were two eyes had IOP greater than 30 mmHg within 30 min, four eyes showed normal IOP at 30 min, and then developed ghost cell glaucoma within 1 day, two eyes developed ghost cell glaucoma between 24 and 48 h. The mean IOP was 46.5 ± 8.0 mmHg. All patients gained normal IOP after vitrectomy without medicine for lowering IOP. The presence of ghost cell glaucoma was associated with tractional retinal detachment (RR = 4.60 [2.02 ~ 8.48], p = 0.004) and fibrovascular membrane involving disk (RR = -3.57 [− 7.59 ~ − 0.92], p = 0.03) (AIC = 39.23, AUC = 0.88) in a logistic regression model.

Conclusion

Attention to postoperative IOP should be paid to patients with PDR undergoing vitrectomy who receive a preoperative IV of anti-VEGF agents. PDR patients with tractional retinal detachment or fibrovasucular membrane involving optic disc are more likely to develop ghost cell glaucoma after IV.

Can the dexamethasone intravitreal implant Ozurdex be safely administered in an out-of-operating room setting?

Purpose

To describe a standardized protocol of the dexamethasone intravitreal (DEX) implant Ozurdex (Allergan, Dublin, Ireland) performed in a controlled environment surgical cabin (CESC).

Methods

Retrospective and observational study conducted on patients who underwent a DEX implant between May 2011 and June 2019, in a third level University Hospital. The controlled environment surgical cabin (ArcSterile, Imex, Valencia, Spain) used in this study was the MB 20 (2 m width, 1.60 m depth, and 2 m height) with an uninterrupted power system (ARSSAI1) to keep the cabin working for 20 min. The cabin was used in the open mode. A standardized protocol of intravitreal injections in controlled environment surgical cabin was designed.

Results

From May 2011 to February 2015, a total of 454 DEX implants were performed in the operating room, whereas from March 2015 to June 2019, 1054 DEX devices were implanted using the CESC. The mean number of DEX implants/per week was significantly lower in the operating room than in the CESC [2.3 (2.1 to 2.5) versus 3.8 (3.6 to 4.1), mean difference 1.5 (1.2 to 1.8), p < 0.0001]. The incidence of endophthalmitis was similar in the two populations, 0/454 (0.0%; 95% CI 0.0 to 0.81%) and 0/1054 (0.0%; 95% CI 0.0 to 0.35%) in the operating room and in the CESC, respectively.

Conclusions

The CESC may be a good alternative to the conventional operating room for the administration of the intravitreal DEX implant.

Ocular flora in patients undergoing intravitreal injections: antibiotic resistance patterns and susceptibility to antiseptic picloxydine

AIM

To study antibiotic resistance patterns and susceptibility to eye antiseptic picloxydine of conjunctival flora in patients undergoing intravitreal injections (IVIs).

METHODS

Conjunctival swabs were taken in 4 groups of patients, 20 patients in each group (n=80): without IVIs and ophthalmic operations in history (group N1; control group); with the first IVI and antibiotic eye drops Tobrex applied 3d before IVI and 5d after it (group N2); with 20 or more IVIs and repeated courses of antibiotic eye drops (group N3); with the first IVI and antiseptic eye drops Vitabact (picloxydine) applied 3d before IVI and 5d after it (group N4). In groups N2 and N4 swabs were taken at baseline and after the treatment. Efficacy of picloxydine in inhibition of growth of conjunctival isolates susceptible and resistant to antibiotic was studied in vitro. Minimal inhibition concentrations (MIC) were determined with microdilution test.

RESULTS

Two of the three patients who had to undergo the IVI procedure showed conjunctiva bacterial contamination. Along with few Staphylococcus aureus and Gram-negative isolates susceptible to most antibiotics, the majority (71%-77%) of causative agents were coagulase-negative Staphylococci (CoNS), 40%-50% of which were multidrug resistant (MDR). Eye disinfection in the operating room and peri-injection courses of Tobrex or Vitabact resulted in total elimination of isolates found at baseline. However, in 10% and 20% of patients, respectively, recolonization of the conjunctiva with differing strains occurred. In patients with repeated IVI and Tobrex/Maxitrol treatment, the conjunctival flora showed high resistance rates: 90% of CoNS were MDR. In the in vitro study, picloxydine showed bactericidal effect against Staphylococci isolates both antibiotic resistant and susceptible with MIC≥13.56 µg/mL. Incubation of bacteria for 15min in Vitabact eye drops, commercially available form of picloxydine, 434 µg/mL, showed total loss of colony forming units of all tested isolates including Pseudomonas aeruginosa.

CONCLUSION

The confirmed efficacy of eye antiseptic picloxydine against conjunctival bacterial isolates and the presence of its commercial form, 0.05% eye drops, convenient for use by patients before and after injection, make this eye antiseptic promising for prophylaxis of IVI-associated infectious complications.

Prophylaxis measures for postinjection endophthalmitis

Intravitreal injections have become the most commonly performed ophthalmic procedure, transforming modern retina practice. Postinjection endophthalmitis, while rare, remains the most feared potential complication. Prophylaxis measures including topical antisepsis, hand hygiene, gloves, masks, and drapes have all been proposed to help prevent postinjection endophthalmitis; however, there remains significant variation in protocol, given the lack of agreement among retina specialists on which steps are crucial to prevent endophthalmitis. With millions of injections performed annually, collating data have helped us better understand risk factors for endophthalmitis after intravitreal injection. We summarize the consensus guidelines for intravitreal injection technique and comprehensively review the literature on prevention of postinjection endophthalmitis.

[Protocol of intravitreal drug delivery. Consensus of the Expert Counsil of Retina and Optic Nerve Diseases of the All-Russian Public Organasation «Association of Ophthalmologists»]

Intravitreal drug administration is a procedure that has become widespread in modern ophthalmology. However, there is no global consensus on certain aspects of this manipulation, and practitioners feel the need for guidelines. In the Russian Federation, until now, such a document was not available. The expert council on diseases of the retina and optic nerve of All-Russian public organization «Association of Ophthalmologists», with participation of invited specialists, has studied and analyzed the existing foreign guidelines for performing intravitreal injections, as well as the regulatory framework in Russia. As a result, this Protocol was developed and approved for use in the healthcare system of the Russian Federation. The document regulates the requirements for specialists and organizations, the conditions for performing the procedure and the necessary material resources and presents an algorithm for performing intravitreal drug administration, a patient examination check-list for various conditions of the procedure, as well as parameters for evaluating and monitoring the quality of the procedure.

Effects of Intravitreal Bevacizumab Therapy in Patients with Proliferative Diabetic Retinopathy

INTRODUCTION

Diabetes mellitus (DM) stands out as one of the chronic diseases with the highest morbidity and mortality rates worldwide. Among the many complications of DM, diabetic retinopathy (DR) is one of the causes of blindness in patients aged between 20 and 64 years. At least 90% of the new cases showed to have the retinal structure and function restored when proper treatment was provided.

AIM

To evaluate the efficacy of the antiangiogenic bevacizumab in the treatment of DR according not only to the clinical laboratory parameters for glycated hemoglobin (HbA1C) and capillary glycemia but also to the ophthalmological parameters for optical coherence tomography (OCT) and best-corrected visual acuity (BCVA).

PATIENTS AND METHODS

A total of 11 individuals were included and followed up for 12 months after 3 administrations of bevacizumab.

RESULTS

Upon associating the ophthalmological and laboratory variables throughout the treatment, no significant alterations could be seen regarding the analyzed variables. However, it was observed that HbA1c values and the total leukocyte count negatively interfered with the treatment response.

CONCLUSION

The current study showed that HbA1c values and the amount of leukocytes negatively interfere with the therapeutic response. Therefore, laboratory analyses of these parameters are recommended for diabetic patients undergoing the above-mentioned treatment.

Bevacizumab versus triamcinolone for persistent diabetic macular edema: a randomized clinical trial

PURPOSE

To evaluate 24-week visual acuity and anatomic outcomes of two "pro re nata" (prn) treatment strategies (intravitreal bevacizumab [IVB] prn versus intravitreal triamcinolone acetonide [IVT] prn) in patients with persistent diabetic macular edema (pDME) after 24 weeks of prn-IVB.

METHODS

One hundred eyes with center-involving DME were enrolled and treated with prn-IVB for 24 weeks; at week 24, eyes with pDME (central subfield thickness [CST] on spectral domain optical coherence tomography > 300 μm) were randomized to IVB monthly prn (group I; prn-IVB) or IVT every 3 months prn (group II; prn-IVT) and eyes in which the CST was ≤ 300 μm were assigned to continue prn-IVB (group III).

RESULTS

Seventy-four eyes completed a 48-week study period. At week 24, 65 (79.3%) eyes still had DME with CST > 300 μm and, therefore, were randomized to prn-IVB (group I, n = 33) or prn-IVT (group II, n = 32); the remaining 17 (20.7%) eyes had CST ≤ 300 μm and were assigned to continued treatment with prn-IVB (group III). At baseline, mean CST (μm) ± standard error of the mean (SEM) was 447.2 ± 24.4, 478.0 ± 19.7, and 386.0 ± 21.0 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no significant difference in mean CST between groups I and II (369.9 ± 23.3 and 426.0 ± 26.1, respectively; p = 0.9995). A significant reduction in mean CST, compared with baseline, was noted at weeks 28 (p = 0.0002) and 44 (p = 0.0002) in group II. Group I did not show a significant reduction in mean CST compared with baseline at any study visit. There were no significant differences in mean CST between groups I and II at any study visit. At baseline, mean ± SEM best-corrected visual acuity (BCVA) (logMAR) was 0.50 ± 0.00, 0.60 ± 0.10, and 0.50 ± 0.10 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no statistically significant difference in mean BCVA between groups I and II (0.50 ± 0.10 and 0.80 ± 0.10, respectively; p = 0.4473). There was no significant improvement in mean BCVA, as compared with baseline, at any study follow-up visit in any of the groups. Group II demonstrated significantly lower BCVA after 24 weeks of IVT (at week 48) compared with baseline (p = 0.0435). There was no significant difference in mean BCVA between groups I and II at any time-point.

CONCLUSION

In eyes with pDME after 24 weeks of treatment with prn-IVB, there was no difference between continued treatment with prn-IVB versus a treatment switch to prn-IVT with respect to mean BCVA or mean CST at week 48. However, BCVA was stable in the prn-IVB group, while prn-IVT was associated with BCVA reduction from baseline and a higher risk of IOP elevation.

[Antibiotic resistance in patients after serial intravitreal injections]

Despite the lack of convincing data on the effectiveness of antibiotic therapy in the prevention of Post-Injection Endophthalmitis (PIE), the use of topical antibiotics for intravitreal injections is still a common practice. Frequent, monthly use of antibiotics results in changes of the composition of conjunctival flora and spontaneous mutations of bacteria, and leads to selective survival of resistant and virulent strains that can cause serious damage inside the eye.

Real-World Trends in Intravitreal Injection Practices among American Retina Specialists

PURPOSE

To analyze practice patterns used for intravitreal injections (IVIs) by retinal specialists in the United States.

DESIGN

Cross-sectional online survey.

PARTICIPANTS

Retina specialists in the United States who responded to a web-based survey.

METHODS

Retinal specialists in the United States were contacted via e-mail to complete a web-based, anonymous, 24-question survey. Multivariate analysis was performed on a selected question of interest focused on choice of anesthetic used for IVI.

MAIN OUTCOME MEASURES

Differences in IVI practices, such as antibiotic preferences, and different odds of anesthetic use by demographic variables with 95% confidence intervals.

RESULTS

A total of 281 retinal specialists responded to the survey (17% response rate). Respondents' average age was 53 years, with an average of 20 years in practice. Respondents practiced in 42 states, with 90% practicing in an urban or suburban area. For anesthesia, 14% used a topical anesthetic with cotton swab compression, 27% used a subconjunctival anesthetic, and 31% used an anesthetic gel. Age, gender, geographic location, and practice setting did not seem to impact choice of anesthetic for IVI significantly. Sixty-six percent of respondents always use a lid speculum, 21% administer topical antibiotics before injection, 36% wear a mask, 73% wear gloves, and 45% always dilate the eyes before injection. Most respondents use a 30-gauge needle and inject in the inferior temporal quadrant (70%). Forty-five percent always perform bilateral injections the same day if indicated. After the injection, 14% administer post operative nonsteroidal anti-inflammatory drugs, 28% administer postoperative antibiotics, and 31% routinely check intraocular pressure after injection.

CONCLUSIONS

This study provided real-world trends in practices for IVI among retina specialists in the United States. In addition, age, gender, practice type, and geographic location did not influence anesthetic choice for IVI.

Efficacy and safety of intravitreal drug injections using a short 34-gauge needle

PURPOSE

To evaluate the efficacy and safety of intravitreal drug injections using a short 34-gauge needle.

STUDY DESIGN

Retrospective study.

METHODS

This study included patients with age-related macular degeneration, diabetic macular edema, or macular edema associated with retinal vein occlusion. We reviewed the medical records of consecutive patients with one of those three diseases treated with antivascular endothelial growth factor (VEGF) agents using an 8-mm-long 34-gauge needle. Sustained intraocular pressure (IOP) elevations were defined as IOP exceeding 21 mmHg or 6-mmHg or higher increases from baseline on 2 consecutive visits at least 1 month apart. The main outcome measures were improved best-corrected visual acuity (BCVA), central retinal thickness (CRT), IOP changes, and incidence of complications related to the 34-gauge needle.

RESULTS

Six hundred ninety-eight injections were administered to 243 consecutive patients (mean age, 74.0 years) and reviewed. The mean follow-up time was 30.2 ± 15.9 weeks. The mean number of intravitreal injections/eye was 2.7 ± 1.8 (range, 1-9). The mean BCVA improved significantly (P < .0001), from 0.43 ± 0.4 logarithm of the minimum angle of resolution (logMAR) units at baseline to 0.36 ± 0.41 logMAR units at the last visit. The mean CRT decreased significantly (P < .0001), from 426.9 ± 168.5 microns at baseline to 297.6 ± 121.1 microns at the last visit. The mean IOP decreased significantly (P < .0001), from 13.6 ± 3.0 mmHg at baseline to 12.9 ± 3.1 mmHg at the visit after the first injection. A retinal tear occurred in 0.14%/injection (1/698). A sustained IOP elevation occurred in 1.29%/injection (9/698).

CONCLUSION

Despite a few complications, the short 34-gauge needle was efficacious and safe for anti-VEGF intravitreal injections.

Hypotensive efficacy of topical brimonidine for intraocular pressure spikes following intravitreal injections of antivascular endothelial growth factor agents: a randomised crossover trial

PURPOSE

To determine the effect of topical brimonidine tartrate prophylaxis on intraocular pressure (IOP) spikes following intravitreal injection of antivascular endothelial growth factor (anti-VEGF) agents.

METHODS

This is a randomised crossover trial of consecutive non-glaucomatous eyes receiving intravitreal anti-VEGF injections between December 2016 and July 2017. All eyes were randomly assigned to no prophylaxis or topical brimonidine tartrate 0.15 % administered 20 min prior to injection in one of two consecutive visits. Measurements of IOP were obtained immediately (T0), 10 min (T10) and 20 min (T20) after injection during the visits with and without prophylaxis.

RESULTS

Among the 58 eyes of 55 patients (116 visits), the mean (SD) age was 74.3 (11.6), and 62% were female. The mean baseline IOP was 15.3 (2.3) mm Hg (range: 11-20). On average, the immediate postinjection IOP during the visit without prophylaxis was 41.6 (12) mm Hg (range: 17-81). Compared with no prophylaxis, the visit with preadministered topical brimonidine tartrate had a lower IOP at T0 (p<0.001), T10 (p=0.001) and T20 (p=0.043), and a smaller proportion of eyes with IOP elevation of greater than 20 mm Hg from preinjection (p=0.002) and IOP greater than 50 mm Hg at T0 (p=0.036). Without prophylaxis, two eyes (two patients) had an IOP of greater than 70 mm Hg at T0 and thus underwent anterior chamber paracentesis.

CONCLUSION

Topical brimonidine tartrate prophylaxis for intravitreal injection of anti-VEGF agents effectively reduces IOP spikes in non-glaucomatous eyes and may be easily incorporated into ophthalmologists' current practice.

TRIAL REGISTRATION NUMBER

NCT03513172.

Topical antibiotics and intravitreal injections

There is increasing evidence that topical antibiotics, given before and/or after intravitreal injections, are ineffective in preventing endophthalmitis and are possibly harmful. In addition to the lack of efficacy and increased development of resistant organisms, the use of topical antibiotics adds significantly to the cost of delivering intravitreal therapy. Despite this, in many countries, it is still common practice to use pre- and/or postinjection topical antibiotics. This review outlines the general principles of effective antibiotic prophylaxis, and the evidence regarding topical antibiotic use as a prophylactic measure for endophthalmitis following intravitreal injections. A key distinguishing feature of intravitreal injections from most other invasive procedures is the fact that they are often repeated on multiple occasions to the same eye. Given the lack of evidence to support topical antibiotics as an effective method of prophylaxis for postinjection endophthalmitis, it appears that more widespread education of ophthalmologists is required to avoid continued inappropriate use. Revision of drug labels in some jurisdictions, and amendment of local/professional society guidelines, may be required to assist in achieving this goal. Emphasis should be placed on antisepsis and aseptic technique, which are the major proven methods of endophthalmitis prevention, rather than antibiotics.

Synthesis, physicochemical properties and ocular pharmacokinetics of thermosensitive in situ hydrogels for ganciclovir in cytomegalovirus retinitis treatment

Ganciclovir (GCV) is one of the most widely used antiviral drugs for the treatment of cytomegalovirus (CMV) retinitis. In this context, the aim of this study was to design in situ thermosensitive hydrogels for GCV ocular delivery by intravitreal injection to achieve sustained drug release behavior and improved ocular bioavailability in the treatment of CMV retinitis. A thermosensitive poly-(β-butyrolactone-co-lactic acid)-polyethylene glycol-poly (β-butyrolactone-co-lactic acid) (PBLA-PEG-PBLA) triblock copolymer was synthesized by ring-opening polymerization and characterization. The GCV-loaded PBLA-PEG-PBLA in situ hydrogels (15%, w/w) were then prepared with drug concentration at 2 mg·mL^-1 and the gelation temperatures, rheological properties, in vitro degradation and syringeability of in situ hydrogels for intravitreal injection were also investigated. Membraneless dissolution model was used to explore drug release behavior of PBLA-PEG-PBLA in situ hydrogel. The results indicated that more than 45 and 85% of GCV can be released within 24 and 96 h, respectively, which was verified by a non-Fickian diffusion mechanism. In vivo ocular pharmacokinetics study showed that area under drug-time curve (AUC) and half-life of PBLA-PEG-PBLA in situ hydrogel was higher (AUC was 61.80 μg·mL^-1·h (p < .01) and t_1/2 was 10.29 h in aqueous humor; AUC was 1008.66 μg·mL^-1·h (p < .01) and t_1/2 was 13.26 h (p < .01) in vitreous) than GCV injection with extended therapeutic activity. Based on obtained results, it was concluded that the thermosenstive PBLA-PEG-PBLA in situ hydrogel is a promising carrier of GCV for intravitreal injection.

Incidence of Endophthalmitis after Intravitreal Injections: Risk Factors, Microbiology Profile, and Clinical Outcomes

PURPOSE

To report the incidence and characteristics of endophthalmitis after intravitreal injections (IVI) of antivascular endothelial growth factor agents and triamcinolone acetonide.

METHODS

Patients' medical records were retrospectively reviewed from January 2009 to June 2016, and the incidence, risk factors, clinical and microbiological characteristics of post-IVI endophthalmitis were evaluated.

RESULTS

The total number of intravitreal injections given, which included ranibizumab, bevacizumab, and triamcinolone acetonide, was 20,566, of which 27 cases developed endophthalmitis, giving an overall incidence of 0.131%. Significant reduction (p < 0.003) in incidence of endophthalmitis was observed in patients who received prefilled compounded bevacizumab injections (0.050%) compared to multiple bevacizumab injections from a single vial (0.235%). In the triamcinolone acetonide group, the incidence was 0.26%. Staphylococcus species were isolated from 18 cases (67%), and all strains were sensitive to vancomycin.

CONCLUSIONS

Adherence to strict aseptic protocols and use of prefilled compounded bevacizumab injections reduces the rate of post-IVI endophthalmitis.

2018 Update on Intravitreal Injections: Euretina Expert Consensus Recommendations

Intravitreal injections (IVI) have become the most common intraocular procedure worldwide with increasing numbers every year. The article presents the most up-to-date review on IVI epidemiology and techniques. Unfortunately, important issues related to pre-, peri- and postinjection management lack randomized clinical trials for a final conclusion. Also, a great diversity of approaches exists worldwide. Therefore, expert consensus recommendations on IVI techniques are provided.

Three-Monthly Intravitreal Bevacizumab Injections for Neovascular Age-Related Macular Degeneration: Short-Term Visual Acuity Results

Purpose.

To evaluate the change in vision after 3 monthly consecutive intravitreal injections of 1.25 mg of bevacizumab for neovascular age-related macular degeneration (AMD).

Methods.

A retrospective analysis of 35 eyes was performed. Visual acuity (VA) at initial visit and at each follow-up visit was compared. The injection of bevacizumab was performed at 30-day intervals and patients were observed for 5 months after the last injection.

Results.

Of the 35 eyes, 9 had received previous treatment with photodynamic therapy with or without 4 mg of intravitreal triamcinolone. VA was measured in Snellen table and transformed into logMAR for statistical purposes. Mean age was 76.66 years (range, 49–90 years). There were 24 (69%) women and 11 (31%) men. Mean VA at the initial visit was 0.92±0.50. At month 1, mean VA was 0.84±0.51 and at month 2 was 0.74±0.51. At month 3, mean VA remained 0.74±0.49. Six and 8 months after the initial visit, VA was 0.79±0.49 and 0.77±0.50, respectively. The improvement in VA was statistically significant at month 2 and at the end of the follow-up (8 months) compared with the baseline VA.

Conclusions.

Three consecutive monthly injections of intravitreal bevacizumab to treat neovascular AMD is effective in improving VA in the short term. Longer prospective studies should be performed to confirm VA stability after the third injection.