Drug safety evaluation of intravitreal triamcinolone acetonide

Multimodal imaging to distinguish microvascular and morphological changes in retinal vein occlusion after intravitreal ranibizumab with or without triamcinolone acetonide injection

BACKGROUND

The study was designed to investigate microvascular and morphological changes in retinal vein occlusion (RVO) using multimodal imaging after intravitreal ranibizumab (IVR) with or without triamcinolone acetonide (IVTA) injections.

METHODS

This was a retrospective and observational study. Fifty patients (52 eyes) diagnosed with RVO were enrolled. Best corrected visual acuity (BCVA), ophthalmoscopy, fundus fluorescein angiography (FFA), spectral domain optical coherence tomography (SDOCT), and optical coherence tomography angiography (OCTA) were employed sequentially both before treatment and at the last visit after treatment.

RESULTS

The mean logMAR VAs in BRVO eyes decreased significantly after treatment (P = 0.029). OCTA showed there was a significant difference in foveal avascular zone (FAZ) in BRVO eyes (P = 0.024), superificial foveal vessel density in both CRVO (P = 0.0004) and BRVO eyes (P = 0.02155). OCT showed the foveal thickness had significant differences after treatment in both CRVO (P < 0.0001) and BRVO eyes (P = 0.0001). BCVA was associated most commonly with ellipsoid zone integrity (P = 0.022). The BCVA in eyes treated with IVR and IVTA was significantly decreased compared with IVR only in BRVO group (P = 0.021). However, the combination of IVR + IVTA significantly improved intraocular pressure (IOP) compared with IVR only in BRVO group (P = 0.037).

CONCLUSION

Both IVR and IVR + IVTA can significantly improve the central vision, macular structure, and functions in BRVO group. Simultaneous IVR with IVTA can significantly increase BCVA compared with IVR only in BRVO group.

Intravitreal Dexamethasone Implant (Ozurdex) for Ocular Toxocariasis

This study aimed to evaluate the efficacy and safety of intravitreal dexamethasone implants in the treatment of ocular toxocariasis (OT). A retrospective analysis was performed on 6 cases in which laboratory tests diagnosed OT. All patients were administered with intravitreal dexamethasone implants with or without vitrectomy. The average follow-up time was 19.7 months. All operated eyes achieved anatomic success, and all patients' visual acuity was improved. Five of these six had a visual acuity of 20/100, and three had final acuity of 20/40 or even better. Intravitreal dexamethasone implants can be used to treat different types of OT, which not only effectively control inflammation and improve the patient's vision but also reduce the use of systemic glucocorticoids.

Effect of Oral Prednisone on the Prevention and Management of Proliferative Vitreoretinopathy After Open-Globe Injury

Purpose: To determine the impact of oral prednisone on the final visual acuity (VA) and prevention of proliferative vitreoretinopathy (PVR) in patients having pars plana vitrectomy (PPV) for globe injuries. Methods: A retrospective chart review was performed of all globe injuries with an initial repair and subsequent PPV between 2009 and 2018. Data included the initial VA, zones of injury, initial closure date, time to secondary intervention (PPV), oral prednisone (1 mg/kg/day) use, the final VA, and enucleation rate. Multivariable regression models were used to assess the impact of oral prednisone use on anatomic and functional outcomes. Results: The mean (±SD) patient age was 46.25 ±18.56 years (range, 13-92); 131 (83.9%) were men. Oral prednisone intake was recorded in 81 patients (52.3%). The prednisone group had significantly more zone 3 involvement (P = .001), worse initial VA (2.28 vs 1.92 logMAR; P = .003), and a greater mean number of surgeries (P = .020) than the no-steroids (control) group but an equivalent final logMAR VA (1.57 vs 1.52; P = .881). The prednisone group had significant VA improvement (P = .025); however, oral prednisone use did not predict the development of PVR (29.23% vs 12.90%; odds ratio [OR], 2.81; 95% CI, 0.89-8.85) or retinal detachment (27.27% vs 29.58%; OR, 0.59; 95% CI, 0.23-1.56). Conclusions: Despite a worse initial clinical presentation, patients who received oral prednisone had significant visual improvement compared with the control group. However, oral prednisone (1 mg/kg/day) use at the time of injury did not decrease the PVR rate.

Conbercept for Treatment of Neovascular Age-Related Macular Degeneration and Visual Impairment due to Diabetic Macular Edema or Pathologic Myopia Choroidal Neovascularization: A Systematic Review and Meta-Analysis

Background: Conbercept is a new anti-vascular endothelial growth factor (VEGF) drug. Here, we systematically conducted the efficacy, safety, compliance, and pharmacoeconomic evaluation of intravitreal conbercept (IVC) compared with other treatments in patients with neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME), or pathologic myopia choroidal neovascularization (pmCNV). Methods: Databases of PubMed, Embase, Cochrane Library, ClinicalTrials.gov, SinoMed, China National Knowledge Infrastructure, and WanFang Data were systematically searched from the inception to July 27, 2021. Randomized clinical trials and pharmacoeconomic studies comparing IVC with control groups in adults with nAMD, DME, or pmCNV were reviewed and selected. Meta-analyses were performed using the fixed-effects model when pooled data were homogeneous. Heterogeneous data were analyzed using the random-effects model. Primary outcomes included visual improvement rate, mean change in visual acuity or best corrected visual acuity, and pharmacoeconomic outcomes. Additional outcomes were the mean change in fundus examination values, adverse events (AEs), quality-of-life measures, and number of injections. Results: Among 3,591 screened articles, 22 original studies with 1,910 eyes of patients were finally included. For nAMD and DME, IVC was significantly associated with better visual acuity or best corrected visual acuity improvement and fundus quantitative measures than placebo, laser photocoagulation (LP), or intravitreal triamcinolone acetonide (IVT). However, IVC showed non-inferior efficacy to intravitreal ranibizumab (IVR) according to low quality of evidence, and there was lack of trials comparing the priority of IVC to other anti-VEGF regimens. No definitive increased risk of ocular or non-ocular AEs were observed in the study groups. All patients with AEs recovered after symptomatic treatments, and no severe AEs occurred. Patients treated with IVC might have higher quality-of-life scores than those in IVR in nAMD or LP in DME. Additionally, IVC showed cost-utility advantages in nAMD and cost-effectiveness advantages than IVR in pmCNV in China. Conclusion: IVC is well-tolerated and effective for improving vision acuity and quantitative measures in fundus condition in patients with nAMD and DME compared with LP, IVT, and placebo, but gains comparable efficacy to IVR. However, well-designed, large-sample, and long-term evaluation of IVC shall be conducted in additional studies worldwide.

Topical Triamcinolone Acetonide-Loaded Liposome Formulation Used as an Adjuvant to Intravitreal Ranibizumab Therapy for Neovascular Age-Related Macular Degeneration

Novel strategies have been developed to reduce or avoid intravitreal injections (IVTs) of the antiangiogenic (ranibizumab (RBZ)) and anti-inflammatory (triamcinolone acetonide (TA)) agents used to treat vitreoretinal diseases. One of the strategies includes liposomes. This study evaluated the safety and efficacy of a topical triamcinolone-loaded liposome formulation (TALF) as an adjuvant to intravitreal RBZ therapy in treatment- naïve patients with neovascular age-related macular degeneration (nAMD). Subjects were randomly assigned to the RBZ-TALF or the RBZ-pro re nata (RBZ-PRN) groups. Patients from the RBZ-TALF group were instructed to apply TALF for 12 months after a single dose of RBZ. Patients from the RBZ-PRN group received three monthly RBZ-IVTs. Retreatment with RBZ was considered in the case of nAMD reactivation. Regarding safety, non-ocular abnormalities were observed during TALF therapy. Concerning efficacy, non-significant differences were identified in terms of visual acuity or central foveal thickness when the RBZ-PRN and RBZ-TALF groups were compared. It is worth noting that the average number of RBZ injections was significantly lower in the RBZ-TALF group (2.5 ± 1.4 vs. 6.1 ± 1.3 IVTs; p = 0.0004). Therefore, TALF used as an adjuvant to RBZ reduces the need for RBZ-IVT retreatment with optimal visual and anatomic results.

Comparative study of pars plana vitrectomy with or without intravitreal dexamethasone implant for idiopathic epiretinal membrane

Purpose:

To investigate if use of adjunctive intravitreal dexamethasone implant during pars plana vitrectomy (PPV) leads to faster visual recovery and reduction of retinal thickness in idiopathic epiretinal membrane (ERM).

Methods:

In this non-randomized, comparative, interventional study 30 eyes (from 30 patients with idiopathic ERM) were enrolled. In the control group (n = 15), patients underwent 25-G pars plana vitrectomy (PPV) and ERM peeling. In the study group (n = 15), each patient underwent the same procedure as those in the control group, and also received an additional dexamethasone implant. Primary outcome after treatment was mean gain in best corrected visual acuity (BCVA), and secondary outcome was reduction in central retinal thickness (CRT). Data were analyzed using Fisher's exact test, Wilcoxon rank sum test, and two-sample t-test.

Results:

The mean gain in BCVA (logMAR) from baseline at 1-month follow-up was significantly higher in the study group (median = - 0.3, IQR = - 0.4, - 0.1) than in the control group (median = 0, IQR = - 0.1, 0.3; P < 0.008). However, no significant difference in mean gain in BCVA between the two groups was detectable at the 6-month follow-up (P < 0.55). At 1-month follow-up, one and seven patients in the control and study groups gained ≥15 letters of BCVA (P < 0.05), respectively. The mean reductions in CRT at the 1-month follow-up were significantly higher in the study group than in the control group (Mean = - 60 μm, SD = 92.1; P < 0.014; 95% CI = 19.75–156.54). The difference in mean reduction of CRT at 6 months was not significant (P < 0.24).

Conclusion:

Adjunctive dexamethasone implant can aid faster visual recovery after PPV in idiopathic ERM, although the implants do not affect long-term gains in visual acuity.

Safety and Tolerability of Topical Ophthalmic Triamcinolone Acetonide-Loaded Liposomes Formulation and Evaluation of Its Biologic Activity in Patients with Diabetic Macular Edema

Intravitreal injections (IVTs) of corticosteroids as triamcinolone acetonide (TA) are frequently used for the treatment of many vitreous and retinal disorders. However, IVTs are related to severe ocular complications. Lately, a topical ophthalmic TA-loaded liposomes formulation (TALF) was designed to transport TA into the posterior segment of the eye when instilled on the ocular surface. To evaluate the safety, tolerability, and biological activity of TALF, an animal study and a phase I clinical assay were performed. Moreover, four patients with diabetic macular edema (DME) were treated with TALF in order to explore the biological activity of the formulation. No inflammation, lens opacity, swelling, or increase in intraocular pressure were recorded after the instillation of TALF in any of the animal or clinical studies. Mainly, mild and transient adverse events such as dry eye and burning were reported. TALF significantly improves visual acuity and diminishes central foveal thickness in patients with DME. The current data demonstrate the safety, tolerability, and biological activity of TALF. It seems that TALF can be used topically to treat vitreous and retinal diseases that respond to TA such as DME, avoiding the use of corticosteroid IVTs and their associated hazards.

Clinically established biodegradable long acting injectables: An industry perspective

Long acting injectable formulations have been developed to sustain the action of drugs in the body over desired periods of time. These delivery platforms have been utilized for both systemic and local drug delivery applications. This review gives an overview of long acting injectable systems that are currently in clinical use. These products are categorized in three different groups: biodegradable polymeric systems, including microparticles and implants; micro and nanocrystal suspensions and oil-based formulations. Furthermore, the applications of these drug delivery platforms for the management of various chronic diseases are summarized. Finally, this review addresses industrial challenges regarding the development of long acting injectable formulations.

Preoperative, Intraoperative and Postoperative Corticosteroid Use as an Adjunctive Treatment for Rhegmatogenous Retinal Detachment

The treatment for rhegmatogenous retinal detachment (RRD) is surgery, including pars plana vitrectomy (PPV) and scleral buckling (SB). Despite surgical advances, degeneration of the photoreceptors and post-operative complications, such as proliferative vitreoretinopathy (PVR), often occurs as the result of inflammation, preventing complete visual recovery or causing RRD recurrence. There is increasing evidence that in the presence of RRD, the activation of inflammatory processes occurs and the surgery itself induces an inflammatory response. This comprehensive review focuses on the use of different formulations of corticosteroids (CCS), as an adjunctive treatment to surgery, either PPV or SB, for RRD repair. The purpose was to review the efficacy and safety of CCS in improving functional and anatomical outcomes and in preventing postoperative complications. This review is organized according to the timing of CCS administration: preoperative, intraoperative, and postoperative. The evidence reviewed supported the role of the pre-operative use of CCS in the treatment of combined RRD and choroidal detachment (CD), reducing CD height. No solid consensus exists on intraoperative and postoperative use of CCS to treat and prevent postoperative complications. However, a large randomized clinical trial including more than 200 eyes suggested that oral prednisone after surgery decreases the rate of postoperative grade B PVR.

Rebound Phenomenon after Intravitreal Injection of Triamcinolone Acetonide for Macular Edema

INTRODUCTION

The aim of this article was to report on a rebound phenomenon after intravitreal triamcinolone acetonide (IVTA) injection for macular edema secondary to diabetic retinopathy (DR) and central or branch retinal vein occlusion (CRVO/BRVO).

METHODS

The data were analyzed retrospectively. Complete ophthalmic examinations, including spectral domain optical coherence tomography, were performed before and 2 months after IVTA injection. The incidence of a rebound phenomenon was defined as an increase in central retinal thickness of >10% from baseline at 2 months after IVTA injection.

RESULTS

This retrospective study included 211 consecutive patients (268 eyes). One hundred ninety (71.2%), 39 (14.6%), and 39 (14.6%) eyes had macular edema (ME) due to DR, CRVO, and BRVO. In total, 9.7% of the eyes showed a rebound phenomenon (DR: 9.5%, CRVO: 5.2%, BRVO: 15.4%). The mean number of prior injections of vascular endothelial growth factor inhibitor or corticosteroid agent was statistically significantly higher in the rebound group (6.8 vs. 5.3) than in the nonrebound group (p = 0.01).

CONCLUSION

Our study shows that 9.7% of the eyes with ME secondary to DR and RVO developed a rebound phenomenon following IVTA injection, limiting its therapeutic effect. We found an increased number of prior intravitreal pharmacotherapy to be a risk factor for a rebound phenomenon.

Use of a Juvenile Rabbit Animal Model to Evaluate Therapeutic Interventions for Postoperative Inflammation and Fibrin Formation After Lensectomy

Purpose

We used the juvenile rabbit as a model for investigating therapeutic interventions for postoperative inflammation and fibrin formation following intraocular lens (IOL) insertion for management of pediatric cataracts.

Methods

Twelve 6- to 7-week-old, 600 to 900 g rabbits underwent bilateral clear-cornea lensectomy via irrigation and aspiration with IOL insertion. Following wound closure, enoxaparin 8 mg (n = 6 eyes), preservative-free triamcinolone 0.5 mg (n = 6), 8 mg enoxaparin plus 0.5 mg triamcinolone (n = 6), or balanced salt solution (n = 6) was injected into the anterior chamber. Slit-lamp examinations and optical coherence tomography (OCT) scans were performed postoperatively on days 3 through 7, and 14 to characterize levels of inflammation and fibrin. Using 17 additional rabbits, enzyme-linked immunosorbent assays (ELISAs) with 100 μL of aqueous humor were performed to quantify the amount of fibrinogen and fibrin preoperatively and on postoperative day 3. Immunohistochemistry was performed to confirm the presence of fibrin.

Results

Enoxaparin alone and combined with triamcinolone reduced the amount of fibrin present in the anterior chamber compared to untreated eyes, which corresponded to an increase in OCT signal strength. Despite the clear visual axis shown in clinical images, the combination treatment group had the highest levels of soluble fibrin when assessed by ELISA. Immunohistochemistry confirmed the presence of insoluble fibrin seen clinically.

Conclusions

A combination of enoxaparin and triamcinolone appears to provide the most therapeutic benefit by reducing fibrin formation and postoperative inflammation.

Translational Relevance

The juvenile rabbit is an excellent model to investigate inflammation and fibrin formation following lensectomy with IOL insertion and possibly any intraocular surgery in children.

Novel Triamcinolone Acetonide-Loaded Liposomes Topical Formulation for the Treatment of Cystoid Macular Edema After Cataract Surgery: A Pilot Study

Purpose: To report tolerability, safety, and efficacy of a topical triamcinolone acetonide-loaded liposomes formulation (TA-LF) in targeting the macular area in patients with refractory pseudophakic cystoid macular edema (PCME).

Methods: For tolerability, safety and efficacy evaluation, 12 eyes of 12 patients with refractory PCME were exposed to one drop of TA-LF (TA at 0.2%) every 2 h for 90 days or until best-corrected visual acuity (BCVA) was achieved. Intraocular pressure (IOP), slit lamp examination, and central foveal thickness (CFT) were analyzed at every visit.

Results: Patients with refractory PCME under TA-LF therapy showed a significant improvement in BVCA and CFT without significant IOP modification (P = 0.94). On average CFT decreased to 206.75 ± 135.72 μm and BCVA improved to 20.08 ± 10.35 letters (P < 0.0005). BCVA was achieved at 10.58 ± 6.70 weeks (range 2–18). TA-LF was well tolerated in all cases. Neither ocular surface abnormalities nor adverse events were recorded.

Conclusion: TA-LF was well tolerated and improved BCVA and CFT on patients with refractory PCME.

Characterization and Pharmacokinetics of Triamcinolone Acetonide-Loaded Liposomes Topical Formulations for Vitreoretinal Drug Delivery

PURPOSE

To achieve a safer alternative to intravitreal injection of corticosteroids, we developed and characterized triamcinolone acetonide-loaded liposomes formulations (TA-LFs) to be used topically for vitreoretinal drug delivery.

METHODS

Four different 0.2% TA-LFs (TA-LF1 to TA-LF4) were generated and submitted to physicochemical characterization. Posteriorly, an ex vivo diffusion assay was performed using rabbit corneas as membranes. Finally, concentrations of triamcinolone acetonide (TA) were determined by high-performance liquid chromatography in ocular tissues from New Zealand white rabbits after multiple topical doses of TA-LF2 (6 times per day, 14 days). In addition, toxicity and tolerability of TA-LF2 was evaluated by cell viability assay and eye examination of study animals, respectively.

RESULTS

TA-LF2 was the most stable formulation maintaining a stable hidrogenion potential (pH) at 30 and 40°C and even improving encapsulation with higher temperature. TA-LF2 and TA-LF3 presented the best diffusion performance in vitro reaching the highest TA concentrations after 8 h of follow-up. In vivo diffusion and pharmacokinetics analysis showed that concentrations of TA in retina and vitreous reached the highest peak at 12 h after topical administration of TA-LF2 (252.10 ± 90.00 ng/g and 32.6 ± 10.27 ng/g, respectively) and subsequently decline to 24.0 ± 11.72 ng/g and 19.5 ± 13.14 ng/g, respectively, at 14 days of follow-up. Finally, cell viability was unaffected by TA-LF2, and no increase in intraocular pressure nor ocular alterations were observed after topical administration of this formulation in rabbits.

CONCLUSION

TA-loaded liposomes, administered topically, can deliver TA in the vitreous cavity and reach the retina efficiently.

Clear, Aqueous Topical Drop of Triamcinolone Acetonide

The objective of this study was to develop a clear aqueous mixed nanomicellar formulation (NMF) of triamcinolone acetonide (TA) with a combination of nonionic surfactant hydrogenated castor oil 60 (HCO-60) and octoxynol-40 (Oc-40). In order to delineate the effects of drug-polymer interactions on entrapment efficiency (EE), loading efficiency (LE), and critical micellar concentration (CMC), a design of experiment (DOE) was performed to optimize the formulation. In this study, full-factorial design has been used with HCO-60 and OC-40 as independent variables. All formulations were prepared following solvent evaporation and film rehydration method, characterized with size, polydispersity, shape, morphology, EE, LE, and CMC. A specific blend of HCO-60 and Oc-40 at a particular wt% ratio (5:1.5) produced highest drug EE, LE, and smallest CMC (0.0216 wt%). Solubility of TA in NMF improved 20 times relative to normal aqueous solubility. Qualitative ¹H NMR studies confirmed the absence of free drug in the outer aqueous NMF medium. Moreover, TA-loaded NMF appeared to be highly stable and well tolerated on human corneal epithelial cells (HCEC) and human retinal pigment epithelial cells (D407 cells). Overall, these studies suggest that TA in NMF is safe and suitable for human topical ocular drop application.

Fluocinolone acetonide for the treatment of diabetic macular edema

INTRODUCTION

Fluocinolone acetonide intravitreal implant is a non-erodible implant approved for the treatment of diabetic macular edema (DME) insufficiently responsive to available therapies. Areas covered: The injectable intravitreal implant releases fluocinolone acetonide at an average rate of 0.2 µg/day for at least 36 months. The two pooled pivotal FAME trials showed that, in patients with DME previously treated with laser photocoagulation, fluocinolone acetonide intravitreal implant was more beneficial than sham injection when looking at the proportion of patients with an improvement from baseline in visual acuity of more than 15 letters at 24 months and at 36 months. Cataract (82%) and intraocular pressure (IOP) elevation (37%) were the most common adverse events. Raised IOP was mostly treated with IOP-lowering medications, with <5% of eyes requiring incisional IOP-lowering surgery. FAME trial program results are confirmed by a series of real-world studies in eyes with chronic/recalcitrant DME. Expert opinion: data indicate that fluocinolone acetonide intravitreal implant is a useful second-line option for the treatment of DME.

Structural Analysis of the Glucocorticoid Receptor Ligand-Binding Domain in Complex with Triamcinolone Acetonide and a Fragment of the Atypical Coregulator, Small Heterodimer Partner

The synthetic glucocorticoids (GCs) dexamethasone, mometasone furoate, and triamcinolone acetonide are pharmaceutical mainstays to treat chronic inflammatory diseases. These drugs bind to the glucocorticoid receptor (GR), a ligand-activated transcription factor and member of the nuclear receptor superfamily. The GR is widely recognized as a therapeutic target for its ability to counter proinflammatory signaling. Despite the popularity of GCs in the clinic, long-term use leads to numerous side effects, driving the need for new and improved drugs with less off-target pharmacology. X-ray crystal structures have played an important role in the drug-design process, permitting the characterization of robust structure-function relationships. However, steroid receptor ligand-binding domains (LBDs) are inherently unstable, and their crystallization requires extensive mutagenesis to enhance expression and crystallization. Here, we use an ancestral variant of GR as a tool to generate a high-resolution crystal structure of GR in complex with the potent glucocorticoid triamcinolone acetonide (TA) and a fragment of the small heterodimer partner (SHP). Using structural analysis, molecular dynamics, and biochemistry, we show that TA increases intramolecular contacts within the LBD to drive affinity and enhance stability of the receptor-ligand complex. These data support the emerging theme that ligand-induced receptor conformational dynamics at the mouth of the pocket play a major role in steroid receptor activation. This work also represents the first GR structure in complex with SHP, which has been suggested to play a role in modulating hepatic GR function.

Adjunctive intraocular and peri-ocular steroid (triamcinolone acetonide) versus standard treatment in eyes undergoing vitreoretinal surgery for open globe trauma (ASCOT): study protocol for a phase III, multi-centre, double-masked randomised controlled trial

BACKGROUND

Eyes sustaining open globe trauma are at high risk of severe visual impairment. Ocular injuries which result in visual loss invariably affect the posterior segment of the eye, and prevention of visual loss involves posterior segment (vitreoretinal) surgery. Despite improvements in vitreoretinal surgical techniques, outcomes in these patients remain unsatisfactory, and development of the intraocular scarring response proliferative vitreoretinopathy is the leading cause. Proliferative vitreoretinopathy is the most common cause of recurrent retinal detachment in these eyes; it is reported to occur in up to 45 % of cases.

METHODS/DESIGN

The Adjunctive Steroid Combination in Ocular Trauma (ASCOT) trial is a multi-centre, double-masked, parallel-arm randomised controlled trial with an internal pilot designed to investigate the effectiveness and cost-effectiveness of using intravitreal and sub-Tenon's triamcinolone acetonide peri-operatively in patients undergoing vitrectomy following open globe trauma. In total, 300 eyes of 300 patients will be recruited and randomly allocated to one of two treatment groups. Both groups will receive standard surgical treatment and routine pre-operative and post-operative treatment and care. The treatment group will receive an adjunctive peri-operative steroid combination (triamcinolone acetonide) consisting of 4 mg/0.1 ml into the vitreous cavity and 40 mg/1 ml into the sub-Tenon's space. The trial incorporates a two-stage internal pilot to examine projected recruitment and retention rates. Progression criteria from the internal pilot study will enable us to determine whether to undertake the main trial. Patients and primary outcome assessors will be masked to treatment allocation. The primary outcome will be an improvement from baseline to 6 months of at least 10 on the corrected visual acuity as measured by ETDRS letter score. Secondary outcomes will be development of scarring, retinal detachment, intraocular pressure abnormalities, quality of life and public sector service use.

DISCUSSION

This is the first powered, controlled clinical trial to investigate the use of adjunctive triamcinolone in patients undergoing vitrectomy following open globe trauma.

TRIAL REGISTRATION

EudraCT2014-002193-37 . Registered on 5 September 2014. ISRCTN30012492 . Registered on 5 September 2014.

Novel strategies for the treatment of diabetic macular edema

Macular edema such as diabetic macular edema (DME) and diabetic retinopathy are devastating back-of-the-eye retinal diseases leading to loss of vision. This area is receiving considerable medical attention. Posterior ocular diseases are challenging to treat due to complex ocular physiology and barrier properties. Major ocular barriers are static (corneal epithelium, corneal stroma, and blood-aqueous barrier) and dynamic barriers (blood-retinal barrier, conjunctival blood flow, lymph flow, and tear drainage). Moreover, metabolic barriers impede posterior ocular drug delivery and treatment. To overcome such barriers and treat back-of-the-eye diseases, several strategies have been recently developed which include vitreal drainage, laser photocoagulation and treatment with biologics and/or small molecule drugs. In this article, we have provided an overview of several emerging novel strategies including nanotechnology based drug delivery approach for posterior ocular drug delivery and treatment with an emphasis on DME.

Intravitreal Injection--Technique and Safety

Intravitreal (IVT) injection of therapeutic agents has become one of the most commonly performed procedures in ophthalmology. Over the past decade, a number of guidelines have been published that recommend proper techniques to increase the safety of IVT injections. Among the various complications of IVT injections, endophthalmitis can be sight threatening. The reported endophthalmitis rates after IVT injection range from 0.020% to 0.085%, which are higher than what would be expected from a simple, fast, and relatively atraumatic procedure. The 2 key issues involved in the prevention of endophthalmitis are pre-IVT injection disinfection using povidone-iodine (PVI) and the use of topical antibiotics as prophylaxis. Whereas 5% PVI for 5 minutes is most commonly used in cataract surgery for disinfection, the duration in IVT injection is much less and can be as short as 30 seconds. Further studies seem warranted to investigate whether longer duration of PVI application in IVT injection can lower the endophthalmitis rate. Recent data suggest that there is inadequate evidence to support the routine use of prophylactic pre-, peri-, or postinjection antibiotics to reduce the risk of endophthalmitis. However, as many confounding factors such as the PVI regimens were not standardized in previous studies, it is too soon to make a concrete conclusion. Despite the availability of published guidelines, considerable variations still exist in real-life clinical situations. In this article, we describe our IVT injection practice protocol and compare it with the most recent international guidelines. Finally, a summary table that shows the clinical features of true, sterile, and pseudoendophthalmitis is presented.

Impact on intraocular pressure after 20-mg decanted triamcinolone acetonide (kenalog) injection when using prophylactic antiglaucoma therapy

PURPOSE

To analyze intraocular pressure (IOP) response after 20-mg decanted intravitreal triamcinolone acetonide followed by early prophylactic IOP-lowering therapy.

METHODS

Overall, IOP results of 120 high-dose decanted intravitreal triamcinolone acetonide injections from 58 nonglaucomatous patients with macular edema, with antiglaucoma therapy prescribed from Week 1 regardless of baseline IOP were retrospectively reviewed.

RESULTS

In cases of consistent compliance with IOP-lowering drugs (79.2%), IOP increased by 2 mmHg at 4 months (P = 0.300) and returned to baseline at 6 months. In cases of noncompliance (20.8%), IOP increased by 7 mmHg at 1 month (P < 0.001) and returned to baseline after starting treatment. Multivariate regression analysis showed that nonvitrectomized eyes and noncompliance with IOP-lowering drugs were independent predictors of increase in IOP greater than 21 mmHg (P = 0.0098 and P = 0.0019, respectively). Nonvitrectomized eyes had a 46% greater chance to experience increase in IOP compared with vitrectomized ones. Poor compliance with IOP-lowering drugs lead to a 45% greater likelihood of experiencing increase in IOP compared with compliant patients. Multiple injections were not associated with the increased risk for increase in IOP greater than 21 mmHg (P = 0.273). Of 120 cases, 2 eyes (1.7%) developed uncontrolled IOP and required glaucoma surgery by 4 months, with good final IOP outcome.

CONCLUSION

Twenty milligram decanted intravitreal triamcinolone acetonide can be safely used to treat macular edema in nonglaucomatous patients; IOP elevation can be adequately controlled with prophylactic antiglaucoma drugs. Noncompliance with prophylactic therapy creates an early spike in IOP, and vitreous status can significantly impact increase in IOP. Compliance with IOP-lowering drugs should be stressed to patients receiving high-dose intravitreal triamcinolone acetonide especially in cases of nonvitrectomized eyes.

Safety of transfoveal subthreshold diode micropulse laser for fovea-involving diabetic macular edema in eyes with good visual acuity

PURPOSE

To determine the safety of transfoveal subthreshold diode micropulse laser for fovea-involving diabetic macular edema.

METHODS

The records of all patients treated with transfoveal subthreshold diode micropulse laser for fovea-involving diabetic macular edema in two retina clinics were reviewed. The eligibility included fovea-involving diabetic macular edema by spectral domain optical coherence tomography and pretreatment visual acuity of 20/40 or better.

RESULTS

Thirty-nine eyes of 27 patients aged 50 years to 87 years (mean, 69 years) were included. Postoperative follow-up ranged from 3 months to 36 months (mean, 11 months). Fourteen patients were insulin dependent, and 19 had nonproliferative retinopathy. The preoperative visual acuity was 20/20 (10 eyes), 20/25 (10 eyes), 20/30 (8 eyes), and 20/40 (11 eyes). No eye had evidence of laser-induced macular damage by any imaging means postoperatively. There were no adverse treatment effects. Logarithm of the minimum angle of resolution visual acuity was improved on average of 0.03 units at 4 months to 7 months of follow-up (P = 0.0449, paired t-test) and otherwise stable. The central foveal thickness was improved at 4 months to 7 months (P = 0.05, paired t-test) and 8 months to 12 months, postoperatively (P = 0.04, mixed model accounting). Maximum macular thickness was improved at 4 months to 7 months postoperatively (P = 0.01, paired t-test and mixed model accounting).

CONCLUSION

In a small retrospective series, transfoveal subthreshold diode micropulse laser was safe and effective for the treatment of fovea-involving diabetic macular edema in eyes with good preoperative visual acuity that were not the candidates for conventional photocoagulation or intravitreal injection. Further study is warranted.

Supramolecular nanofibers of triamcinolone acetonide for uveitis therapy

Supramolecular nanofibers of prodrugs hold advantages for drug release due to their high drug payload, sustained and constant drug release behavior, and stimuli responsiveness. In this study, we report on a supramolecular hydrogel mainly formed by a clinically used drug triamcinolone acetonide (TA). Such a hydrogel could only be prepared via an ester bond hydrolysis process from its prodrug of succinated triamcinolone acetonide (STA). The resulting hydrogel could constantly release TA in the in vitro release experiment. The TA hydrogel possessed an excellent transscleral penetration ability, as evaluated by the in vitro transscleral transport study. The developed TA hydrogel also exhibited a great ocular compatibility in rats, as indicated by the optical coherence tomography (OCT) images, HE observation, and glial fibrillary acidic protein (GFAP) and vimentin immuno-staining assays of the retinas. Our TA hydrogel showed a decreased efficacy to inhibit ocular inflammation in the rat's experiment autoimmune uveitis (EAU) model compared to the commercial TA suspension (Transton), but without causing complications such as high intraocular pressure and cataracts. These promising properties of the hydrogel indicated its great potential for the treatment of eye diseases.

Anesthetic effectiveness of topical levobupivacaine 0.75% versus topical proparacaine 0.5% for intravitreal injections

Background and Purpose:

Today no method of topical anesthesia for intravitreal injection administration has been proven to make the patient comfortable yet. We compared the efficacy of topical levobupivacaine 0.75% and proparacaine 0.5% in patients undergoing intravitreal injections.

Materials and Methods:

A prospective, randomized study comparing two agents for topical anesthesia in intravitreal injections. Ninety-six consecutive patients were enrolled into two groups to receive either topical levobupivacaine 0.75% (n=48) or proparacaine 0.5% (n=48). Patients were asked to score their pain using a visual analog scale (VAS) immediately following the injection. The average of these scores was used as the primary outcome. The surgeon performing the procedure scored his perception of the patients’ pain using the Wong-Baker FACES scale.

Results:

Mean VAS pain scores for two groups were found to be 44.77 ± 16.42 and 34.18 ± 14.83, respectively. Mean VAS pain score in the proparacaine group was significantly lower than that in the levobupivacaine group (P= 0.003). Mean Wong-Baker FACES scores for the two groups were 1.08 ± 0.49 and 1.10 ± 0.30, respectively. There was no statistically significant difference between levobupivacaine and proparacaine groups (P=0.824).

Conclusions:

Topical proparacaine 0.5% was more effective in preventing pain during intravitreal injections.

The results of pars plana vitrectomy and silicone oil tamponade for endophthalmitis after intravitreal injections

To report the role of early vitrectomy and silicone oil tamponade in acute endophthalmitis following intravitreal injection. Medical records of eight patients who presented with acute endophthalmitis after intravitreal injection of different drugs were retrospectively reviewed. Initial treatment consisted of vitreous tap with cultures and injection of intravitreal antibiotics, with the patients subsequently undergoing pars plana vitrectomy and silicone oil tamponade within 24 h following initial vitreous tap. The mean time to presentation was 1.7 days (1-3 days). The initial best-corrected visual acuity was hand motion to 0.05 before treatment and 0.05-0.8 (Snellen) after treatment. Vitreous cultures were obtained from all patients, of which four were culture positive. Endophthalmitis was controlled in all patients. There was no retinal detachment or phthisis bulbi during the follow-up period (1-4 years). Acute endophthalmitis following intravitreal injection occurs rapidly and requires urgent treatment. If intravitreal antibiotics fail to control inflammation, early pars plana vitrectomy and silicone oil tamponade would be an appropriate option.