Triamcinolone acetonide in ocular therapeutics

Comprehensive analysis of prohibited substances and methods in sports: Unveiling trends, pharmacokinetics, and WADA evolution

This review systematically compiles sports-related drugs, substances, and methodologies based on the most frequently detected findings from prohibited lists published annually by the World Anti-Doping Agency (WADA) between 2003 and 2021. Aligned with structure of the 2023 prohibited list, it covers all proscribed items and details the pharmacokinetics and pharmacodynamics of five representatives from each section. Notably, it explores significant metabolites and metabolic pathways associated with these substances. Adverse analytical findings are summarized in tables for clarity, and the prevalence is visually represented through charts. The review includes a concise historical overview of doping and WADA's role, examining modifications in the prohibited list for an understanding of evolving anti-doping measures.

Diagnosis of an unusual orbital abscess following sub-Tenon's steroid injection: a case report

Orbital abscesses are caused by infection within or near the orbit and show obvious signs of pain, proptosis and raised inflammatory markers. Diagnosis is based on clinical features and radiological imaging, and requires early antibiotics and often surgical drainage to save vision. Sub-Tenon's injections of triamcinolone acetonide (TA) have caused localized infections in previous reports, which have responded to therapeutic interventions. Here we report a case where a delayed presentation of an orbital abscess secondary to sub-Tenon's TA for persistent post-operative cystoid macular oedema, without obvious signs of infection, rapidly progressed to cause orbital compartment syndrome. Despite treatment, the patient lost complete vision in the affected eye. This case discusses the rare and unusual cause of abscess formation and a diagnostic dilemma.

Triamcinolone-loaded self nano-emulsifying drug delivery systems for ocular use: An alternative to invasive ocular surgeries and injections

Inflammation of the posterior segment of the eye is a severe condition and hard to cure as delivery of drugs to the inflammation site is inefficient. Currently, the primary treatment approach is ocular surgery or invasive ocular injections. Herein, we designed and developed a topically self nano-emulsifying drug delivery system (SNEDDs) to deliver triamcinolone acetonide (TCA) to the posterior segment of the eye. A screening based on TCA solubility was conducted on each excipient followed by preparation of various formulations using different ratios of the selected excipients. Vesicles of optimized SNEDDs had less than 100 nm size and spherical morphology. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay showed self-emulsified vesicles have relatively high safety on retinal pigment epithelium (RPE) cell line. Furthermore, efficient cellular uptake of coumarin 6-loaded SNEDDs in RPE using confocal laser scanning microscopy (CLSM) was confirmed. In addition, an in-vivo study using hematoxylin and eosin (H&E) staining revealed that 14 days of topical treatment of albino rabbit eyes with TCA-loaded SNEDDs was safe and no sign of tissue destruction and inflammation was detected in different parts of the eye sections including cornea, sclera, retina, and optic nerve. Also, the CLSM images from topically treated eyes with coumarin 6 (a hydrophobic, fluorescent drug model) loaded SNEDDs, showed that the optimized SNEDDs could properly penetrate toward the posterior segments of the eye especially the retina, posterior parts of the choroid, and sclera. Considering the outstanding results obtained by ocular tissue penetration and low toxicity, prepared SNEDDs, have the potential to be used as a topical administration for treating posterior segment disorders of the eye through an utterly non-invasive route and TCA-loaded SNEDDs could be an alternative for TCA intravitreal and intra conjunctival injections.

Comparing the efficacy of glucocorticoids and anti-VEGF in treating diabetic macular edema: systematic review and comprehensive analysis

Introduction

The aim of this study was to better understand the efficacy of various drugs, such as glucocorticoids and anti-vascular endothelial growth factors (VEGF), in the treatment of diabetic macular edema (DME), and to evaluate various clinical treatment regimens consisting of different therapeutic measures.

Methods

This study included randomized controlled trials up to February 2023 comparing the efficacy of corticosteroid-related therapy and anti-VEGF therapy. PubMed, the Cochrane Library, and Embase were searched, and the quality of the studies was carefully assessed. Finally, 39 studies were included.

Results

Results at 3-month followup showed that intravitreal injection of bevacizumab (IVB) + triamcinolone acetonide (TA) was the most beneficial in improving best-corrected visual acuity and reducing the thickness of macular edema in the center of the retina in patients with DME. Results at 6-month follow-up showed that intravitreal dexamethasone (DEX) was the most effective in improving patients' bestcorrected visual acuity and reducing the thickness of central macular edema.

Discussion

Overall, IVB+TA was beneficial in improving best-corrected visual acuity and reducing central macular edema thickness over a 3-month follow-up period, while DEX implants had a better therapeutic effect than anti-VEGF agents at 6 months, especially the patients with severe macular edema and visual acuity impaired.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=397100, identifier CRD42023397100.

Up-to-date molecular medicine strategies for management of ocular surface neovascularization

Ocular surface neovascularization and its resulting pathological changes significantly alter corneal refraction and obstruct the light path to the retina, and hence is a major cause of vision loss. Various factors such as infection, irritation, trauma, dry eye, and ocular surface surgery trigger neovascularization via angiogenesis and lymphangiogenesis dependent on VEGF-related and alternative mechanisms. Recent advances in antiangiogenic drugs, nanotechnology, gene therapy, surgical equipment and techniques, animal models, and drug delivery strategies have provided a range of novel therapeutic options for the treatment of ocular surface neovascularization. In this review article, we comprehensively discuss the etiology and mechanisms of corneal neovascularization and other types of ocular surface neovascularization, as well as emerging animal models and drug delivery strategies that facilitate its management.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

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

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

Recent advances and future prospects: current status and challenges of the intraocular injection of drugs for vitreoretinal diseases

Effective drug therapy for vitreoretinal disease is a major challenge in the field of ophthalmology; various protective systems, including anatomical and physiological barriers, complicate drug delivery to precise targets. However, as the eye is a closed cavity, it is an ideal target for local administration. Various types of drug delivery systems have been investigated that take advantage of this aspect of the eye, enhancing ocular permeability and optimizing local drug concentrations. Many drugs, mainly anti-VEGF drugs, have been evaluated in clinical trials and have provided clinical benefit to many patients. In the near future, innovative drug delivery systems will be developed to avoid frequent intravitreal administration of drugs and maintain effective drug concentrations for a long period of time. Here, we review the published literature on various drugs and administration routes and current clinical applications. Recent advances in drug delivery systems are discussed along with future prospects.

Immune response in retinal degenerative diseases - Time to rethink?

Retinal degeneration comprises a group of diseases whereby either the retinal neurons or the neurovascular unit degenerates leading to the loss of visual function. Although the initial cause varies in different conditions, inflammation is known to play an important role in disease pathogenesis. Recent advances in molecular and cell biology and systems biology have yielded unexpected findings, including the heterogeneity of immune cells in the degenerative retina, bidirectional neuron-microglia cross talk, and links to the gut microbiome. Here we discuss the immune response in retinal degenerative conditions, taking into account both regional (retinal) and systemic factors. We propose to classify retinal degeneration into dry and wet forms based on whether the blood-retinal barrier (BRB) is breached and fluid is accumulated in retinal parenchyma. The dry form has a relatively intact BRB and is characterised by progressive retinal thinning. Immune response to degenerative insults is dominated by the retinal defence system, which remains to be regulated by neurons. In contrast, the wet form has retinal oedema due to BRB damaged. Inflammation is executed by infiltrating immune cells as well as the retinal defence system. The gut microbiome will have easy access to the retina in wet retinal degeneration and may affect significantly retinal immune response.

Suprachoroidal Space Triamcinolone Acetonide: A Review in Uveitic Macular Edema

Triamcinolone acetonide injectable suspension for suprachoroidal use (Xipere^®; SCS triamcinolone acetonide) is a corticosteroid approved in the USA for the treatment of macular edema associated with uveitis. Suprachoroidal injection of SCS triamcinolone acetonide results in preferential distribution into the posterior segment, which may reduce the risk of corticosteroid-related adverse events, such as cataracts and intraocular pressure (IOP) elevation. In a multicenter phase III trial in patients with non-infectious uveitic macular edema, SCS triamcinolone acetonide significantly and rapidly improved visual acuity and reduced signs of macular edema compared with sham treatment. SCS triamcinolone acetonide was generally well tolerated, with the most common adverse event being eye pain on the day of the procedure. The risk of corticosteroid-related IOP elevation appeared to be reduced in unrescued patients in the SCS triamcinolone acetonide group compared with patients in the sham control group who received rescue therapy. SCS triamcinolone acetonide is a novel and useful treatment option for uveitic macular edema.

Uveitic macular edema is a major cause of blindness in the developed world. Intravitreal and periocular application of corticosteroids (e.g., triamcinolone acetonide) may be effective for uveitis and macular edema, but these routes are often associated with cataracts and corticosteroid-related intraocular pressure (IOP) elevation. Recently, a triamcinolone acetonide suspension for injection into the suprachoroidal space (Xipere^®; SCS triamcinolone acetonide) has been approved for the treatment of uveitic macular edema. The suprachoroidal route preferentially distributes the drug to the back of the eye, resulting in a reduced risk of corticosteroid-related adverse events. In a pivotal clinical trial, SCS triamcinolone acetonide rapidly improved visual acuity and resolved macular edema in patients with non-infectious uveitis. SCS triamcinolone acetonide was generally well tolerated, with the most common ocular adverse event being eye pain on the day of procedure. In unrescued patients in the SCS triamcinolone acetonide group, there appeared to be a reduced risk of corticosteroid-related IOP elevation versus patients who received rescue therapy in the sham control group. SCS triamcinolone acetonide is a novel and useful treatment option for uveitic macular edema.

Triamcinolone acetonide injectable suspension for suprachoroidal use in the treatment of macular edema associated with uveitis

Introduction

Macular edema due to noninfectious uveitis is a sight-threatening complication that is routinely treated with corticosteroids. Triamcinolone acetonide injectable suspension for suprachoroidal use (Xipere™) is an alternative treatment option for patients with non-infectious uveitis associated macular edema.

Areas covered

This review describes the recently FDA approved triamcinolone acetonide injectable suspension that can be injected into the suprachoroidal space. This physiological space is between the sclera and choroid. This allows for therapeutic targeting of the retina and choroid. This review highlights published clinical trials for this novel drug preparation.

Expert opinion

Suprachoroidal administration of triamcinolone acetonide has shown improvement in vision and inflammation in studies with non-infectious uveitis associated macular edema. This unique delivery method suggests the potential to decrease side effects of anterior segment exposure such as glaucoma and cataract, but head-to-head trials are needed for further study of safety and efficacy. Additionally, there are promising prospective studies underway for utilization of the suprachoroidal space for other diseases including macular degeneration, diabetic macular edema, and ocular tumors.

[Radiation-induced retinopathy: actual knowledge and new concepts]

Radiation retinopathy is an occlusive vascular pathology following radiotherapy, generally targeted on the eye or peri-ocular structures. Despite increasingly precise techniques (stereotactic radiosurgery, proton therapy, etc.), the inclusion of the retina in the radiation field is sometimes unavoidable. This can lead to a severe pathology, which can ultimately cause blindness or even the anatomical loss of the eye when neovascular glaucoma occurs, due to the abnormal proliferation of neovessels. Radiation retinopathy have been described for more than a century, but it has recently seen great advances in both diagnosis and treatment. The advances of efficient and less invasive examinations in our clinical practice, such as OCT-angiography, allows for easier screening and diagnosis at earlier stages. Thus a new approach to the pathology is necessary, first of all through new definitions and classifications including previously undetected minimal forms. Furthermore, the recent appearance of intravitreal therapies by injection of anti-VEGF or dexamethasone implants has drastically changed the visual prognosis of these patients, who were previously treated only by retinal photocoagulation of the ischaemic areas. Recent studies have even shown the effectiveness of these new molecules in preventing the development of radiation retinopathy. This review of the literature provides an update on this disease and details how these recent diagnostic and therapeutic developments may play a role in the management of this complication.

Ocular Therapeutics and Molecular Delivery Strategies for Neovascular Age-Related Macular Degeneration (nAMD)

Age-related macular degeneration (AMD) is the leading cause of vision loss in geriatric population. Intravitreal (IVT) injections are popular clinical option. Biologics and small molecules offer efficacy but relatively shorter half-life after intravitreal injections. To address these challenges, numerous technologies and therapies are under development. Most of these strategies aim to reduce the frequency of injections, thereby increasing patient compliance and reducing patient-associated burden. Unlike IVT frequent injections, molecular therapies such as cell therapy and gene therapy offer restoration ability hence gained a lot of traction. The recent approval of ocular gene therapy for inherited disease offers new hope in this direction. However, until such breakthrough therapies are available to the majority of patients, antibody therapeutics will be on the shelf, continuing to provide therapeutic benefits. The present review aims to highlight the status of pre-clinical and clinical studies of neovascular AMD treatment modalities including Anti-VEGF therapy, upcoming bispecific antibodies, small molecules, port delivery systems, photodynamic therapy, radiation therapy, gene therapy, cell therapy, and combination therapies.

Anti-inflammatory and neuroprotective properties of the corticosteroid fludrocortisone in retinal degeneration

The pathogenesis of outer retinal degenerations has been linked to the elevation of cytokines that orchestrate pro-inflammatory responses within the retinal milieu, and which are thought to play a role in diseases such as geographic atrophy (GA), an advanced form of AMD. Here we sought investigate the anti-inflammatory and mechanistic properties of fludrocortisone (FA), as well as triamcinolone acetonide (TA), on Müller cell-mediated cytokine expression in response to inflammatory challenge. In addition, we investigated the neuroprotective efficacy of FA and TA in a photo-oxidative damage (PD), a model of outer retinal degeneration. Expression of CCL2, IL-6, and IL-8 with respect to FA and TA were assessed in Müller cells in vitro, following simulation with IL-1β or TNF-α. The dependency of this effect on mineralocorticoid and glucocorticoid signaling was also interrogated for both TA and TA via co-incubation with steroid receptor antagonists. For the PD model, C57BL/6 mice were intravitreally injected with FA or TA, and changes in retinal pathology were assessed via electroretinogram (ERG) and optical coherence tomography (OCT). FA and TA were found to dramatically reduce the expression of CCL2, IL-6, and IL-8 in Müller glia in vitro after inflammatory challenge with IL-1β or TNF-α (P < 0.05). Though FA acts as both a mineralocorticoid and glucocorticoid receptor agonist, co-incubation with selective steroid antagonists revealed that the suppressive effect of FA on CCL2, IL-6, and IL-8 expression is mediated by glucocorticoid signaling (P < 0.05). In PD, intravitreal FA was found to ameliorate outer-retinal atrophy as measured by ERG and OCT (P < 0.05), while TA had no significant effect (P > 0.05). Our data indicate potent anti-inflammatory and mechanistic properties of corticosteroids, specifically FA, in suppressing inflammation and neurodegeneration degeneration associated with outer retinal atrophy. Taken together, our findings indicate that corticosteroids such as FA may have value as a potential therapeutic for outer retinal degenerations where such pro-inflammatory factors are implicated, including AMD.

Comparison of the Effect of Different Local Analgesia Administration Techniques in Total Hip Arthroplasty: A Retrospective Comparative Cohort Study

Objective

To improve postoperative pain management, several authors have described the use of periarticular injection (PAI) or intra-articular injection (IAI) following total hip arthroplasty (THA). However, no comparative studies examining the results between PAI and IAI following THA have been published. This study aimed to evaluate the analgesic and anti-inflammatory effects of PAI and IAI following THA.

Methods

This single-center, retrospective cohort study enrolled patients who underwent unilateral primary THA. A total of 278 patients (281 hips) were included in the final analyses, with 112 patients (113 hips) in the control group, 85 patients (87 hips) in the PAI group, and 81 patients (81 hips) in the IAI group. Numeric rating scale (NRS) scores and laboratory data were assessed preoperatively and on postoperative days (POD) 1 and 7.

Results

NRS scores, creatine phosphokinase, and C-reactive protein levels in the PAI and IAI groups were significantly lower than those in the control group on POD 1 and 7. D-dimer levels were significantly lower in the PAI and IAI groups than in the control group on POD 7. The white blood cell count was significantly higher in the PAI and IAI groups than in the control group on POD 1 and 7. Aspartate transaminase, alanine aminotransferase, blood urea nitrogen, and creatinine levels were within the reference ranges in all three groups at all time points. NRS scores and laboratory data showed no significant differences between the PAI and IAI groups at all time points.

Conclusion

PAI and IAI have equivalent analgesic and anti-inflammatory effects. Considering the technical challenges of PAI, IAI may be preferable because of its simplicity in the case of using a closed suction drain.

Development of Triamcinolone Acetonide-Loaded Microemulsion as a Prospective Ophthalmic Delivery System for Treatment of Uveitis: In Vitro and In Vivo Evaluation

Treatment of uveitis (i.e., inflammation of the uvea) is challenging due to lack of convenient ophthalmic dosage forms. This work is aimed to determine the efficiency of triamcinolone acetonide (TA)-loaded microemulsion as an ophthalmic delivery system for the treatment of uveitis. Water titration method was used to construct different pseudo-ternary phase diagrams. Twelve microemulsion formulations were prepared using oleic acid, Cremophor EL, and propylene glycol. Among all tested formulations, Formulation F3, composed of oil: surfactant-co-surfactant (1:1): water (15:35:50% w/w, respectively), was found to be stable and showed acceptable pH, viscosity, conductivity, droplet size (211 ± 1.4 nm), and zeta potential (−25 ± 1.7 mV) and almost complete in vitro drug release within 24 h. The in vivo performance of the optimized formulation was evaluated in experimentally uveitis-induced rabbit model and compared with a commercial TA suspension (i.e., Kenacort^®-A) either topically or by subconjunctival injection. Ocular inflammation was evaluated by clinical examination, white blood cell count, protein content measurement, and histopathological examination. The developed TA-loaded microemulsion showed superior therapeutic efficiency in the treatment of uveitis with high patient compliance compared to commercial suspension. Hence, it could be considered as a potential ocular treatment option in controlling of uveitis.

Periarticular analgesic injection containing a corticosteroid after total hip arthroplasty may prevent deep venous thrombosis: a retrospective comparative cohort study

BACKGROUND

Of late, periarticular analgesic injection (PAI) has become a common alternative treatment for pain following total hip arthroplasty (THA). However, the systemic effects of PAI containing corticosteroids in patients subjected to THA have not been investigated. This study evaluated the analgesic efficacy and systemic effects of PAI containing a corticosteroid in patients subjected to THA.

METHODS

This single-center, retrospective cohort study enrolled patients undergoing unilateral, primary THA. A total of 197 patients (200 hips) were included in the final analyses, with 87 hips in the PAI group and 113 hips in the control group. Numeric Rating Scale (NRS) and laboratory data were assessed preoperatively and on postoperative days (POD) 1 and 7. Pearson's correlation coefficients were obtained to assess the correlations between the D-dimer level on POD 7 and each outcome measure on POD 1.

RESULTS

The postoperative white blood cell count (WBC) was significantly higher in the PAI group than in the control group. Postoperative NRS, creatine phosphokinase (CK), and C-reactive protein (CRP) levels were significantly lower in the PAI group. D-dimer levels were significantly lower in the PAI group on POD 7. Postoperative aspartate transaminase (AST), alanine aminotransferase, blood urea nitrogen, and creatinine levels were within reference ranges. D-dimer levels on POD 7 showed a significant negative correlation with WBC on POD 1 (r=-0.4652) and a significant positive correlation with the NRS score and AST, CK, CRP, and D-dimer levels on POD 1 (r = 0.1558, 0.2353, 0.2718, 0.3545, and 0.3359, respectively).

CONCLUSIONS

PAI containing a corticosteroid may be an effective treatment for pain and inflammation after THA, and it does not seem to cause drug-induced liver or kidney injury. Moreover, corticosteroid PAI can may accelerate early ambulation, which prevents the elevation of postoperative D-dimer levels, and may reduce the risk of deep venous thrombosis.

COMBINED TREATMENT WITH BEVACIZUMAB AND TRIAMCINOLONE ACETONIDE FOR MACULAR EDEMA DUE TO RETINAL VEIN OCCLUSION

The purpose of this study was to determine the efficacy of combined intravitreal bevacizumab and triamcinolone in the treatment of macular edema due to retinal vein occlusion. A prospective randomized trial was conducted in the Department of Ophthalmology, Osijek University Hospital Centre in Osijek including 51 patients divided into three groups depending on the drug received. The first group received 1.25 mg intravitreal bevacizumab, the second group received 1 mg intravitreal triamcinolone, and the third group received a combination of 1.25 mg bevacizumab and 1 mg intravitreal triamcinolone on the same day. Changes in the central macular thickness, intraocular pressure and visual acuity were monitored during the follow up period. The retinal perfusion status was evaluated by fluorescein angiography. The group that received combined treatment had better outcome in terms of reduction of macular thickness. There was no statistically significant intraocular pressure elevation among the three treatment groups or within each group of patients. A positive trend regarding visual improvement was observed in the group receiving combined treatment in spite of the lowest initial visual acuity, highest value of macular thickness and longest mean duration of symptoms. In conclusion, combined treatment with bevacizumab and triamcinolone for the treatment of retinal vein occlusion is more potent, safe, efficient and cost-effective. It can also be recommended because fewer injections are needed in patients undergoing treatment for macular edema.

Efficacy of intracameral preservative-free triamcinolone acetonide in pediatric cataract surgery: a meta-analysis

PURPOSE

The aim of this study is to evaluate the efficacy of intracameral preservative-free triamcinolone acetonide (TA) on reducing inflammatory reactions after pediatric cataract surgery.

METHODS

Researches were comprehensively searched in PubMed, Embase, and the Cochrane Central Register of Controlled Trials up to 30 November, 2019. Data of interest were extracted and analyzed by Review Manager 5.2. The primary outcome was cell deposits. The secondary outcomes included posterior synechias, fibrinous anterior chamber reaction, visual axis obscuration, and posterior capsule opacification. The odds ratio (OR), weight mean difference (WMD), and their 95% confidence intervals (95% CI) were used to assess the strength of the association.

RESULTS

In total, 45 articles were obtained. Finally, 5 studies with a total of 308 eyes were enrolled in this meta-analysis. Among these, 134 eyes underwent intracameral TA treatment and 174 eyes did not. In intracameral TA treatment group, the incidence of cell deposits (OR = 0.35, 95% CI 0.16-0.76, P = 0.008), posterior synechias (OR = 0.44, 95% CI 0.23-0.86, P = 0.02), and fibrinous anterior chamber reaction (OR = 0.12, 95% CI 0.01-1.05, P = 0.05) were lower compared to those in patients without intracameral TA treatment. Meanwhile, the incidence of visual axis obscuration (OR = 0.10, 95% CI 0.01-0.85, P = 0.04) and posterior capsule opacification (OR = 0.09, 95% CI 0.02-0.55, P = 0.009) were also reduced significantly. The intraocular pressure (IOP) was evaluated at the first month postoperatively (WMD = 0.84 mmHg, 95% CI 0.14-1.53, P = 0.02), but within the normal range. There was no difference of IOP between two groups at 6 months or above after operation (P = 0.93).

CONCLUSIONS

The intracameral preservative-free TA in pediatric cataract surgery contributed to much less inflammatory reaction with the normal IOP range.

Steroid-induced glaucoma: Epidemiology, pathophysiology, and clinical management

Glucocorticoids are a class of anti-inflammatory drugs commonly used to treat various ocular and systemic conditions. Although the role of glucocorticoids in the treatment of numerous serious inflammatory diseases is pivotal, their prolonged use may increase intraocular pressure resulting in steroid-induced glaucoma. We provide a detailed update on steroid-induced glaucoma as a preventable cause of blindness in the adult and pediatric population and describe its epidemiology, social impact, and risk factors. Furthermore, we explore the propensity of different steroids to increase the intraocular pressure, the role of different routes of steroid administration, dosage and duration of treatment, as well as the clinical features, genetics, and management of steroid-induced glaucoma.

Melt-Cast Films Significantly Enhance Triamcinolone Acetonide Delivery to the Deeper Ocular Tissues

Delivering an effective drug load to the posterior section of the ocular tissues, while using a non-invasive technique, has always been a challenge. In this regard, the goal of the present study was to develop sustained release triamcinolone acetonide (TA) loaded polymeric matrix films for ocular delivery. The TA-films were prepared in two different polymer matrices, with drug loadings of 10% and 20% w/w, and they were evaluated for ocular distribution in vivo in a conscious rabbit model. A 4% w/v TA suspension (TA-C) was used as a control for in vitro and in vivo studies. The TA-films, prepared with melt-cast technology, used polyethylene oxide (PEO) and Soluplus^® as the polymer matrix. The films were evaluated with respect to assay, content uniformity, excipient interaction, and permeability across isolated rabbit sclera. The distribution of TA in the ocular tissues, post topical administration, was determined in New Zealand male albino rabbits as a function of dose, and was compared against TA-C. The assay of the 10% and 20% w/w film was in the range from 70–79% and 92–94% for the Soluplus^® and PEO films, respectively, and content uniformity was in the range of 95–103% for both the films. The assay of the TA from Soluplus^® films was less compared with the PEO films and showed an interaction with TA, as revealed by Differential Scanning Calorimetry (DSC). Hence, Soluplus^® films were not selected for further studies. No interaction was observed between the drug and PEO polymer matrix. The enhancement of trans-scleral flux and permeability of TA was about 1.16 and 1.33-folds, respectively, from the 10% w/w PEO and 3.5 and 2.12-folds, respectively, from the 20% w/w PEO films, as compared with TA-C formulations. The in vivo studies demonstrate that significantly higher TA levels were observed in the anterior and posterior segments of the eye at the end of 6h with the PEO films. Therefore, the PEO based polymeric films were able to deliver TA into the back of the eye efficiently and for prolonged periods.

Comparison of a single intraoperative posterior sub-Tenon's capsule triamcinolone acetonide injection versus topical steroids for treatment of postcataract surgery inflammation in children

BACKGROUND:

The aim of this study is to compare the clinical efficacy of a single intraoperative posterior sub-Tenon's capsule triamcinolone acetonide injection with postoperative topical steroids in controlling intraocular inflammation in uncomplicated pediatric cataract surgery.

MATERIALS AND METHODS:

A prospective comparative study of children (<13 years of age) undergoing cataract surgery in a tertiary care eye center in South India. Preoperative evaluation was similar in both groups. The surgical procedure was the same for both groups except at the end of surgery only Group 1 (right eye of bilateral cataracts and all unilateral cataracts) received intraoperative 0.5 ml (40 mg/ml) posterior sub-Tenon's injection of triamcinolone acetonide. Postoperatively, Group 1 was administered only topical antibiotic and Group 2 was put on topical antibiotic, mydriatic, and steroids. Intraocular inflammation and intraocular pressure (IOP) were assessed clinically on day 1, 1^st week, 1^st month, and 3 months, postoperatively.

RESULTS:

A total of 30 eyes were included in the study. Age ranged between 1 month and 132 months, with 18 eyes included in Group 1 and 12 eyes in Group 2. The mean postoperative IOP at the 3 months follow-up was not significantly different between groups (P = 0.4). The presence of intraocular lens had no role in postoperative inflammation (P = 1). Group 2 showed more anterior segment inflammation with six eyes (50%) developing posterior synechiae and distortion of the pupil 3 months postoperatively.

CONCLUSION:

In pediatric cataracts, a single intraoperative sub-Tenon's capsule injection of triamcinolone acetonide appears to be safe and effective in controlling postcataract surgery inflammation.

Update in treatment of uveitic macular edema

Macular edema (ME) represents the most common cause for visual loss among uveitis patients. The management of uveitic macular edema (UME) may be challenging, due to its often recalcitrant nature. Corticosteroids remain the mainstay of treatment, through their capability of effectively controlling inflammation and the associated ME. Topical steroids may be effective in milder cases of UME, particularly in edema associated with anterior uveitis. Posterior sub-Tenon and orbital floor steroids, as well as intravitreal steroids often induce rapid regression of UME, although this may be followed by recurrence of the pathology. Intra-vitreal corticosteroid implants provide sustained release of steroids facilitating regression of ME with less frequent injections. Topical nonsteroidal anti-inflammatory drugs may provide a safe alternative or adjuvant therapy to topical steroids in mild UME, predominantly in cases with underlying anterior uveitis. Immunomodulators including methotrexate, mycophenolate mofetil, tacrolimus, azathioprine, and cyclosporine, as well as biologic agents, notably the anti-tumor necrosis factor-α monoclonal antibodies adalimumab and infliximab, may accomplish the control of inflammation and associated ME in refractory cases, or enable the tapering of steroids. Newer biotherapies have demonstrated promising outcomes and may be considered in persisting cases of UME.

In Situ Gel of Triamcinolone Acetonide-Loaded Solid Lipid Nanoparticles for Improved Topical Ocular Delivery: Tear Kinetics and Ocular Disposition Studies

Triamcinolone acetonide (TA), an intermediate acting corticosteroid, is used in the treatment of posterior ocular diseases, such as inflammation, posterior uveitis, and diabetic macular edema. The objective of this investigation was to prepare TA-loaded solid lipid nanoparticles (TA-SLNs) and in situ gel (TA-SLN-IG) formulations for delivery into the deeper ocular tissues through the topical route. TA-SLNs were prepared by hot homogenization and ultrasonication method using glyceryl monostearate and Compritol® 888ATO as solid lipids and Tween®80 and Pluronic® F-68 as surfactants. TA-SLNs were optimized and converted to TA-SLN-IG by the inclusion of gellan gum and evaluated for their rheological properties. In vitro transcorneal permeability and in vivo ocular distribution of the TA-SLNs and TA-SLN-IG were studied using isolated rabbit corneas and New Zealand albino rabbits, respectively, and compared with TA suspension, used as control (TA-C). Particle size, PDI, zeta potential, assay, and entrapment efficiency of TA-SLNs were in the range of 200⁻350 nm, 0.3⁻0.45, -52.31 to -64.35 mV, 70⁻98%, and 97⁻99%, respectively. TA-SLN-IG with 0.3% gellan gum exhibited better rheological properties. The transcorneal permeability of TA-SLN and TA-SLN-IG was 10.2 and 9.3-folds higher compared to TA-C. TA-SLN-IG showed maximum tear concentration at 2 h, indicating an improved pre-corneal residence time, as well as higher concentrations in aqueous humor, vitreous humor and cornea at 6 h, suggesting sustained delivery of the drug into the anterior and posterior segment ocular tissues, when compared to TA-SLN and TA-C. The results, therefore, demonstrate that the lipid based nanoparticulate system combined with the in situ gelling agents can be a promising drug delivery platform for the deeper ocular tissues.

PEDF protects human retinal pigment epithelial cells against oxidative stress via upregulation of UCP2 expression

To investigate the protective function of pigment epithelium-derived factor (PEDF) against oxidative stress (OS) in ARPE-19 cells, ARPE-19 cells were divided into different OS groups and treated with various concentrations of H₂O₂ (0, 75, 150 and 200 µmol/l) for 24 h. To establish the protective group, 200 ng/ml of PEDF was administered to ARPE-19 cells. Cell Counting Kit-8 assays and cell growth curve experiments were performed to determine levels of cell viability; lactate dehydrogenase and propidium iodide (PI) staining assays were also performed. The expression levels of genes associated with apoptosis as well as uncoupling protein 2 (UCP2) were detected by reverse transcription-quantitative, or semi-quantitative polymerase chain reaction. Furthermore, an OS injury animal model was established in both C57BL/6 and BALB/c mice via injection of 5 µg of PEDF in the vitreous cavity and subsequent injection of 150 µM H₂O₂ following a 24 h time interval. Hematoxylin and eosin (H&E) staining, as well as UCP2 immunofluorescent labeling were also performed. One-way analysis of variance was used to determine statistically significant differences, followed by multiple comparison analysis using the Newman Keuls method. The results of cell viability assays demonstrated that the numbers of apoptotic cells were increased following treatment with H₂O₂ in a dose-dependent manner; however, this effect was reversed following treatment with PEDF. The expression levels of caspase 3 and B cell lymphoma (Bcl2) associated X genes associated with apoptosis were inhibited, whereas levels of the anti-apoptotic gene Bcl2 were enhanced following treatment with PEDF in different passages of ARPE-19 cells. Significant differences were demonstrated in the levels of UCP2 gene expression between the PEDF+ H₂O₂ treated group and cells treated with H₂O₂ alone. Labeling of the UCP2 detector in the confocal images demonstrated decreased UCP2 protein staining in the retinal pigment epithelium (RPE) cells and RPE layers following H₂O₂ injury; however, this effect was inhibited following treatment with PEDF. H&E staining was performed to investigate the thickness of the RPE layers, and the results revealed that thicknesses were significantly increased in sections treated with PEDF during OS, due to increased numbers of RPE cells. Furthermore, PEDF was demonstrated to increase UCP2 gene expression in ARPE-19 cells and animal RPE layers under OS, which suggested that PEDF may protect RPE cells and tissues during oxidative injury.

A non-invasive, multi-target approach to treat diabetic retinopathy

Hyperglycemia invoke number of pathways resulting in development of diabetic retinopathy (DR), including protein kinase C activation, increased expression of VEGF, advanced glycation end product (AGEs) formation and activation of polyol pathway, among which the pathophysiology of aldose reductase (ALR2) of the polyol pathway is evident by more than a decade of research. Subtle involvement of ALR2 in invoking various pathways of diabetic complications has caused an increase in attention towards the identification of novel aldose reductase inhibitors (ARIs). Numerous ARIs of different classes were employed in the treatment of diabetic complications initially, but few came into light as drugs. Though no ALR2 inhibitor has been used for the treatment or control of DR, Epalrestat has been used worldwide for treating diabetic neuropathy. This review critically analyses different treatments available for diabetic retinopathy, their limitations and the importance of the development of novel inhibitors of ALR2 that could prevent progression of DR, by causing a direct or indirect effect on controlling factors associated with DR.

Glycosylation-enhanced biocompatibility of the supramolecular hydrogel of an anti-inflammatory drug for topical suppression of inflammation

Intravitreal/periocular injection of triamcinolone acetonide (TA) suspension is a common uveitis treatment, but it displays a high risk for serious side effects (e.g., high intraocular pressure, retinal toxicity). We report here an intravitreally injectable thermosensitive glycosylated TA (TA-SA-Glu) hydrogel, formed by covalently conjugating glucosamine (Glu) with succinate TA (TA-SA), for treating uveitis. The TA-SA-Glu hydrogelator forms a supramolecular hydrogel spontaneously in aqueous solution with a minimal gelation concentration of 0.25 wt%. Structural analysis revealed that hydrogen bonds assisted by hydrophobic interaction resulted in self-assembled nanofibers. Rheology analysis demonstrated that this TA-SA-Glu hydrogel exhibited a typical thixotropic property. Sustained release of both TA-SA-Glu and TA from the hydrogel occurred throughout the 3-day in vitro release study. The obtained TA-SA-Glu hardly caused cytotoxicity against ARPE-19 and RAW264.7 cells after 24 h of incubation at drug concentration up to 600 μM. In particular, TA-SA-Glu exhibited a comparable anti-inflammatory efficacy to TA in terms of inhibiting the production of nitric oxide, tumor necrosis factor-α, and interleukin-6 in activated RAW264.7 macrophages. Following a single intravitreal injection, 69 nmol TA-SA-Glu hydrogel caused minimal apparent retinal toxicity, whereas the TA suspension displayed significant effects in terms of localized retinal toxicity. A single intravitreal injection of TA-SA-Glu hydrogel was more effective in controlling inflammatory response than that of the TA suspension treatment, particularly in down-regulating the pro-inflammatory Th1 and Th17 effector responses for treating experimental autoimmune uveitis. This study strongly indicates that supramolecular TA-SA-Glu hydrogels may represent a new option for posterior uveitis management.

STATEMENT OF SIGNIFICANCE

Intravitreal/periocular injection of triamcinolone acetonide (TA) suspension is a common uveitis treatment, but suffers a high risk for serious side effects (e.g., high intraocular pressure, retinal toxicity). We generated an injectable glycosylated triamcinolone acetonide hydrogelator (TA-SA-Glu) hydrogel for treating uveitis. Following a single intravitreal injection, the proposed TA-SA-Glu hydrogel hardly caused apparent retinal toxicity at a dosage of 69 nmol per eye. Furthermore, TA-SA-Glu hydrogel was more effective in controlling non-infectious uveitis over than a TA suspension, particularly in terms of down-regulating the pro-inflammatory Th1 and Th17 effector responses for treating experimental autoimmune uveitis (EAU). This study strongly indicates that TA-SA-Glu supramolecular hydrogels may represent a new option for the management of various intraocular inflammations.

Controlled release technology for anti-angiogenesis treatment of posterior eye diseases: Current status and challenges

Antiangiogenic therapeutics, such as corticosteroids, VEGF targeting antibodies and aptamers have been demonstrated effective in controlling retinal and choroidal neovascularization related vision loss. However, to manage the chronic conditions, it requires long term and frequent intravitreal injections of these drugs, resulting in poor patient compliance and suboptimal treatment. In addition, emerging drugs such as tyrosine kinase inhibitors and siRNAs received much expectations, but the late stage clinical trials encountered various obstacles. Controlled release technology could improve the existing treatment regimen by extending therapeutic duration, reducing risks and burdens caused by frequent injections, and enabling new drugs to overcome the hurdles of translation. Here, we give qualitative and quantitative discussions about the principle mechanisms of polymeric reservoir, polymeric matrix and hydrogel systems. We also reveal the design rationales of the existing drug delivery and release systems in preclinical and clinical stages. Lastly, the animal models of ocular angiogenesis diseases are critically reviewed, which could help to facilitate the translation of controlled release technologies from bench to bedside.

A Common Procedure With an Uncommon Pathology: Triamcinolone Acetonide Eyelid Injection

Local corticosteroid injections are frequently employed by ophthalmologists to treat a variety of ocular, periocular, and orbital inflammatory conditions. Triamcinolone acetonide is a slowly dissolving crystalline corticosteroid that is often used for this purpose because of its prolonged anti-inflammatory effect. On occasion, previously injected corticosteroid material persists in tissues longer than anticipated, creating nodules that may masquerade as other disease conditions, or appearing incidentally in excised lesions on histopathologic examination. The histopathologic features of corticosteroid residues are unfamiliar to most ophthalmic pathologists and general pathologists. These features are described herein. Triamcinolone acetonide deposits in the skin appear as pale eosinophilic lakes of acellular frothy material on hematoxylin-eosin staining and are occasionally surrounded by a mild inflammatory reaction.

Principles of pharmacology in the eye

The eye is a highly specialized organ that is subject to a huge range of pathology. Both local and systemic disease may affect different anatomical regions of the eye. The least invasive routes for ocular drug administration are topical (e.g. eye drops) and systemic (e.g. tablets) formulations. Barriers that subserve as protection against pathogen entry also restrict drug permeation. Topically administered drugs often display limited bioavailability due to many physical and biochemical barriers including the pre-corneal tear film, the structure and biophysiological properties of the cornea, the limited volume that can be accommodated by the cul-de-sac, the lacrimal drainage system and reflex tearing. The tissue layers of the cornea and conjunctiva are further key factors that act to restrict drug delivery. Using carriers that enhance viscosity or bind to the ocular surface increases bioavailability. Matching the pH and polarity of drug molecules to the tissue layers allows greater penetration. Drug delivery to the posterior segment is a greater challenge and, currently, the standard route is via intravitreal injection, notwithstanding the risks of endophthalmitis and retinal detachment with frequent injections. Intraocular implants that allow sustained drug release are at different stages of development. Novel exciting therapeutic approaches include methods for promoting transscleral delivery, sustained release devices, nanotechnology and gene therapy.

Distribution of fluorescein sodium and triamcinolone acetonide in the simulated liquefied and vitrectomized Vitreous Model with simulated eye movements

Intravitreal administration is the method of choice for drug delivery to the posterior segment of the eye with special emphasis on the vitreous body and its surrounding retinal vasculature. In order to gain a better understanding of the underlying distribution processes, an in vitro model simulating the vitreous body (Vitreous Model, VM) and a system simulating the impact of movement on the VM (Eye Movement System, EyeMoS) was previously developed. In the study reported here, these systems were modified in regard to a standardized injection procedure, the diversity of simulated eye movements, extended periods of investigation, the opportunity to simulate the state after vitrectomy and in considering the physiological temperature. Fluorescein sodium (FS) and triamcinolone acetonide (TA) were used as (model) drugs to examine the drug distribution within the VM. Vitrectomy was simulated by replacing half the volume of the polyacrylamide gel that was used as vitreous substitute with the clinically used Siluron® 5000 whereas for a simulated liquefaction half the volume of the gel was replaced by buffer. A simulated liquefaction caused a 12-fold faster distribution of FS compared to the simulated juvenile VM, which was most likely caused by convective forces and mass transfer. Also, the injection technique (injection into the gel or into the buffer compartment) influenced the resulting distribution pattern. Without any liquefaction, the previously described initial injection channel occurred with both (model) drugs and, in the case of TA, remained almost unchanged during the investigation period of 72h. Simulating vitrectomized eyes, TA did not spread uniformly, but either remained in the depot or strongly sedimented within the VM suggesting that a homogenous distribution of a TA suspension is highly unlikely in vitrectomized eyes. High variabilities were observed with ex vivo animal eyes, demonstrating the limited benefit of explanted tissues for such distribution studies. The combination of the modified VM and EyeMoS seems a valuable tool for characterizing intravitreal dosage forms in a reproducible simulation of diversified eye movements and a partially liquefied or vitrectomized vitreous body.

Risk of Ocular Hypertension in Adults with Noninfectious Uveitis

PURPOSE

To describe the risk and risk factors for ocular hypertension (OHT) in adults with noninfectious uveitis.

DESIGN

Retrospective, multicenter, cohort study.

PARTICIPANTS

Patients aged ≥18 years with noninfectious uveitis seen between 1979 and 2007 at 5 tertiary uveitis clinics.

METHODS

Demographic, ocular, and treatment data were extracted from medical records of uveitis cases.

MAIN OUTCOME MEASURES

Prevalent and incident OHT with intraocular pressures (IOPs) of ≥21 mmHg, ≥30 mmHg, and increase of ≥10 mmHg from documented IOP recordings (or use of treatment for OHT).

RESULTS

Among 5270 uveitic eyes of 3308 patients followed for OHT, the mean annual incidence rates for OHT ≥21 mmHg and OHT ≥30 mmHg are 14.4% (95% confidence interval [CI], 13.4-15.5) and 5.1% (95% CI, 4.7-5.6) per year, respectively. Statistically significant risk factors for incident OHT ≥30 mmHg included systemic hypertension (adjusted hazard ratio [aHR], 1.29); worse presenting visual acuity (≤20/200 vs. ≥20/40, aHR, 1.47); pars plana vitrectomy (aHR, 1.87); history of OHT in the other eye: IOP ≥21 mmHg (aHR, 2.68), ≥30 mmHg (aHR, 4.86) and prior/current use of IOP-lowering drops or surgery in the other eye (aHR, 4.17); anterior chamber cells: 1+ (aHR, 1.43) and ≥2+ (aHR, 1.59) vs. none; epiretinal membrane (aHR, 1.25); peripheral anterior synechiae (aHR, 1.81); current use of prednisone >7.5 mg/day (aHR, 1.86); periocular corticosteroids in the last 3 months (aHR, 2.23); current topical corticosteroid use [≥8×/day vs. none] (aHR, 2.58); and prior use of fluocinolone acetonide implants (aHR, 9.75). Bilateral uveitis (aHR, 0.69) and previous hypotony (aHR, 0.43) were associated with statistically significantly lower risk of OHT.

CONCLUSIONS

Ocular hypertension is sufficiently common in eyes treated for uveitis that surveillance for OHT is essential at all visits for all cases. Patients with 1 or more of the several risk factors identified are at particularly high risk and must be carefully managed. Modifiable risk factors, such as use of corticosteroids, suggest opportunities to reduce OHT risk within the constraints of the overriding need to control the primary ocular inflammatory disease.

Targeted intracorneal delivery-Biodistribution of triamcinolone acetonide following topical iontophoresis of cationic amino acid ester prodrugs

The aim was to investigate intracorneal iontophoresis of biolabile triamcinolone acetonide (TA) amino acid ester prodrugs (TA-AA). Arginine and lysine esters of TA (TA-Arg and TA-Lys, respectively) were synthesized and characterized; quantification was performed by HPLC-UV and UHPLC-MS/MS. The aqueous solubility of the prodrugs (at pH 5.5) was ∼1000-fold greater than TA. Anodal iontophoresis (10min at 3mA/cm²) of TA-AA was investigated using isolated porcine cornea. Although no statistically significant difference was observed in total intracorneal delivery of TA (468.25±59.70 and 540.85±79.16nmol_TA/cm², for TA-Arg and TA-Lys, respectively), the different susceptibilities of the prodrugs to hydrolysis influenced intracorneal biodistribution. Quantification of TA in twenty-five 40μm thick corneal lamellae revealed significantly deeper penetration of TA following TA-Lys iontophoresis. Its superior resistance to hydrolysis enabled sustained electromigration into the deeper cornea suggesting judicious prodrug selection might enable targeted regioselective drug delivery. The intracorneal biodistribution following anodal iontophoresis of TA-Arg (2.3mM; 10min, 3mA/cm²) was visualized by full field optical coherence tomography providing qualitative confirmation of the extensive intracorneal penetration of TA. Short duration iontophoresis of TA-AA prodrugs may improve deep corneal bioavailability and efficacy in vivo, constituting a "single-shot" treatment option for corneal allograft rejection.

Improved release of triamcinolone acetonide from medicated soft contact lenses loaded with drug nanosuspensions

Drug nanosuspensions (NSs) show a significant potential to improve loading and release properties of the poorly water soluble drug triamcinolone acetonide (TA) from poly(hydroxyethyl methacrylate) (pHEMA) soft contact lenses. In this work, TA NSs were developed by a controlled precipitation method using a fractional factorial Plackett-Burmann design. Poloxamer 407 (PL) and polyvinyl alcohol (PVA) as stabilizing agents were selected. NSs were characterized in terms of their drug content, particle size and morphology. Results indicate that all studied factors, except homogenization speed and sonication, have significant influence on the drug incorporation yield into NSs. Drug nanoparticles showed an interesting size that may be suitable for their incorporation into topical ocular drug delivery systems, as hydrogels. pHEMA hydrogels and daily-wear Hilafilcon B commercial contact lenses (SCLs) were employed to study TA loading capacity and drug release properties using NSs as loading system. Hydrogels have been synthesised by copolymerization of 2-hydroxyethyl methacrylate (HEMA) with methacrylic acid (MA) in accordance with a previous work (García-Millán et al., 2015). Both synthesised hydrogels and SCLs were characterized in terms of their mechanical and physical properties and TA loading and release properties. Selected TA NS was further characterized by studying its physical-chemical stability during the loading process. Results show that the use of TA NSs as loading medium significantly increases drug loading capacity and release of soft contact lenses in comparison with drug saturated solution. Synthesised pHEMA hydrogels and SCLs lenses have good properties as ophthalmic drug delivery systems, but SCLs load higher quantities of drug and release TA in shorter time periods than synthesised pHEMA hydrogel.

Sustained release ophthalmic dexamethasone: In vitro in vivo correlations derived from the PK-Eye

Corticosteroids have long been used to treat intraocular inflammation by intravitreal injection. We describe dexamethasone loaded poly-DL-lactide-co-glycolide (PLGA) microparticles that were fabricated by thermally induced phase separation (TIPS). The dexamethasone loaded microparticles were evaluated using a two-compartment, in vitro aqueous outflow model of the eye (PK-Eye) that estimates drug clearance time from the back of the eye via aqueous outflow by the anterior route. A dexamethasone dose of 0.20±0.02mg in a 50μL volume of TIPS microparticles resulted in a clearance t_1/2 of 9.6±0.3days using simulated vitreous in the PK-Eye. Since corticosteroids can also clear through the retina, it is necessary to account for clearance through the back of the eye. Retinal permeability data, published human ocular pharmacokinetics (PK) and the PK-Eye clearance times were then used to establish in vitro in vivo correlations (IVIVCs) for intraocular clearance times of corticosteroid formulations. A t_1/2 of 48h was estimated for the dexamethasone-TIPS microparticles, which is almost 9 times longer than that reported for dexamethasone suspension in humans. The prediction of human clearance times of permeable molecules from the vitreous compartment can be determined by accounting for drug retinal permeation and determining the experimental clearance via the anterior aqueous outflow pathway using the PK-Eye.

Comparative Effectiveness of Three Prophylactic Strategies to Prevent Clinical Macular Edema after Phacoemulsification Surgery

PURPOSE

To study the relationship of chemoprophylaxis and other factors with the occurrence of acute, clinical, postoperative macular edema.

DESIGN

Retrospective cohort study. The drug regimens consisted of postoperative topical prednisolone acetate (PA) alone or with a nonsteroidal anti-inflammatory drug (NSAID) or intraoperative subconjunctival injection of 2 mg triamcinolone acetonide (TA) alone.

PARTICIPANTS

Patients undergoing phacoemulsification at Kaiser Permanente, Diablo Service Area, Northern California, from 2007 through 2013.

METHODS

We identified incident macular edema diagnoses that had been recorded 5 to 120 days after phacoemulsification with visual acuity 20/40 or worse and evidence of macular thickening by optical coherence tomography. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from logistic regression analysis, conditioned on the surgeon and adjusted for year, patient age and race, diabetic retinopathy status, other ocular comorbidities, systemic comorbidities, and posterior capsular rupture status.

MAIN OUTCOME MEASURES

Incident rates of acute, clinical, postoperative macular edema.

RESULTS

We confirmed 118 cases among 16 070 cataract surgeries (incidence, 0.73%). Compared with PA alone, the OR for the relationship of macular edema with PA+NSAID was 0.45 (95% CI, 0.21-0.95) and that for TA injection was 1.21 (95% CI, 0.48-3.06). The frequency of intraocular pressure spikes of 30 mmHg or more between postoperative days 16 and 45 was 0.6% in the topical PA group, 0.3% in the topical PA+NSAID group (P = 0.13), and 0.8% for the TA group (P = 0.52). Black race was associated with a risk of macular edema (OR, 2.86; 95% CI, 1.41-5.79).

CONCLUSIONS

Adding a prophylactic NSAID to PA treatment was associated with a reduced risk of macular edema with visual acuity of 20/40 or worse. The risk and safety of TA injection were similar to those of PA alone. Further research is needed on the prognostic significance of postoperative macular edema, the role of prophylaxis, the risk among black people, and the effectiveness of depot medications.

Optical coherence tomographic reflectivity of cystoid spaces is related to recurrent diabetic macular edema after triamcinolone

PURPOSE

To determine the association between reflectivity levels in foveal cystoid spaces on optical coherence tomography images and the course of the logarithm of the minimum angle of resolution (logMAR) after triamcinolone acetonide treatment for diabetic macular edema.

METHODS

We retrospectively reviewed 58 consecutive eyes treated with an intravitreal or sub-Tenon's injection of triamcinolone acetonide for diabetic macular edema. The foveal cystoid spaces within central 1 mm were circumscribed, followed by measurement of optical coherence tomography reflectivity. The correlation between the reflectivity and visual outcome was investigated.

RESULTS

The optical coherence tomography reflectivity levels in foveal cystoid spaces increased at 1 month after treatment, but not at 3 months or 6 months. The preoperative reflectivity levels were correlated negatively with logMAR changes from 1 month to 6 months and from 3 months to 6 months but not with logMAR at individual time points compared with the preoperative logMAR. The changes in foveal thickness from 1 month to 6 months were correlated negatively with the baseline reflectivity and positively with logMAR changes from 1 month to 6 months and from 3 months to 6 months.

CONCLUSION

Lower optical coherence tomography reflectivity in foveal cystoid spaces was associated with the rebound in macular thickening and visual deterioration after triamcinolone acetonide treatment for diabetic macular edema.

The PK-Eye: A Novel In Vitro Ocular Flow Model for Use in Preclinical Drug Development

A 2-compartment in vitro eye flow model has been developed to estimate ocular drug clearance by the anterior aqueous outflow pathway. The model is designed to accelerate the development of longer-acting ophthalmic therapeutics. Dye studies show aqueous flow is necessary for a molecule injected into the vitreous cavity to clear from the model. The clearance times of proteins can be estimated by collecting the aqueous outflow, which was first conducted with bevacizumab using phosphate-buffered saline in the vitreous cavity. A simulated vitreous solution was then used and ranibizumab (0.5 mg) displayed a clearance time of 8.1 ± 3.1 days, which is comparable to that observed in humans. The model can estimate drug release from implants or the dissolution of suspensions as a first step in their clearance mechanism, which will be the rate-limiting step for the overall resident time of a candidate dosage form in the vitreous. A suspension of triamcinolone acetonide (Kenalog®) (4.0 mg) displayed clearance times spanning 26-28 days. These results indicate that the model can be used to determine in vitro-in vivo correlations in preclinical studies to develop long-lasting therapeutics to treat blinding diseases at the back of the eye.

Efficient delivery of NF-κB siRNA to human retinal pigment epithelial cells with hyperbranched cationic polysaccharide derivative-based nanoparticles

A hyperbranched cationic polysaccharide derivative-mediated small interfering (si)RNA interference strategy was proposed to inhibit nuclear transcription factor-kappa B (NF-κB) activation in human retinal pigment epithelial (hRPE) cells for the gene therapy of diabetic retinopathy. Two hyperbranched cationic polysaccharide derivatives containing the same amount of cationic residues, but with different branching structures and molecular weights, including 3-(dimethylamino)-1-propylamine-conjugated glycogen (DMAPA-Glyp) and amylopectin (DMAPA-Amp) derivatives, were developed for the efficient delivery of NF-κB siRNA into hRPE cells. The DMAPA-Glyp derivative showed lower toxicity against hRPE cells. Furthermore, the DMAPA-Glyp derivative more readily condensed siRNA and then formed the nanoparticles attributed to its higher branching architecture when compared to the DMAPA-Amp derivative. Both DMAPA-Glyp/siRNA and DMAPA-Amp/siRNA nanoparticles were able to protect siRNA from degradation by nuclease in 25% fetal bovine serum. The particle sizes of the DMAPA-Glyp/siRNA nanoparticles (70–120 nm) were smaller than those of the DMAPA-Amp/siRNA nanoparticles (130–180 nm) due to the higher branching architecture and lower molecular weight of the DMAPA-Glyp derivative. In addition, the zeta potentials of the DMAPA-Glyp/siRNA nanoparticles were higher than those of the DMAPA-Glyp/siRNA nanoparticles. As a result, siRNA was much more efficiently transferred into hRPE cells using the DMAPA-Glyp/siRNA nanoparticles rather than the DMAPA-Amp/siRNA nanoparticles. This led to significantly high levels of suppression on the expression levels of NF-κB p65 messenger RNA and protein in the cells transfected with DMAPA-Glyp/siRNA nanoparticles. This work provides a potential approach to promote hyperbranched polysaccharide derivatives as nonviral siRNA vectors for the inhibition of NF-κB activation in hRPE cells.

Drug loading optimization and extended drug delivery of corticoids from pHEMA based soft contact lenses hydrogels via chemical and microstructural modifications

This paper proposes an approach to improve drug loading capacity and release properties of poly(2-hydroxyethyl methacrylate) (p(HEMA)) soft contact lenses based on the optimization of the hydrogel composition and microstructural modifications using water during the polymerization process. P(HEMA) based soft contact lenses were prepared by thermal or photopolymerization of 2-hydroxyethyl methacrylate (HEMA) solutions containing ethylene glycol di-methacrylate as crosslinker and different proportions of N-vinyl-2-pyrrolidone (NVP) or methacrylic acid (MA) as co-monomers. Transmittance, water uptake, swelling, microstructure, drug absorption isotherms and in vitro release were characterized using triamcinolone acetonide (TA) as model drug. Best drug loading ratios were obtained with lenses containing the highest amount (200 mM) of MA. Incorporation of 40% V/V of water during the polymerization increases the hydrogel porosity giving a better drug loading capacity. In vitro TA release kinetics shows that MA hydrogels released the drug significantly faster than NVP-hydrogels. Drug release was found to be diffusion controlled and kinetics was shown to be reproducible after consecutive drug loading/release processes. Results of p(HEMA) based soft contact lenses copolymerized with ethylene glycol dimethacrylate (EGDMA) and different co-monomers could be a good alternative to optimize the loading and ocular drug delivery of this corticosteroid drug.

Intravitreal combination of dexamethasone sodium phosphate and bevacizumab in the treatment of exudative AMD

The purpose of this study is to investigate the efficacy and safety of intravitreal dexamethasone sodium phosphate (DSP) combined with bevacizumab for the treatment of neovascular age-related macular degeneration (AMD). In this non comparative case study, 30 eyes of 27 patients with CNV due to AMD received intravitreal DSP (0.2 mg) and bevacizumab (1.25 mg) during a 6-month PRN (pro re nata) dosing regimen. Visual acuity, macular thickness and intraocular pressure (IOP) were monitored and recorded. After 6 months, mean retinal thickness decreased from 423.5 ± 75.3 to 228.2 ± 34.5 and mean visual acuity improved from 0.9 ± 0.39 logMAR to 0.53 ± 0.34 (p = 0.001) logMAR. During the trial period, 81 intravitreal injections were performed in 30 eyes, thus the mean number of injections per eye was 2.7 ± 1.1. 86.7% of the eyes required 3 or less injections while only 13.3% needed 4 or more injections. None of the patients, phakic or pseudophakic, manifested an elevation of IOP during the treatment, ranging between 12 and 22 mmHg. Combined DSP and bevacizumab offers encouraging results in the challenge of AMD treatment, providing immediate response of macular edema, reduced number of intravitreal injections and stabilization or improvement of visual acuity.

The functional and histopathologic change in the levator palpebrae superioris and Müller muscle after subconjunctival injection of triamcinolone acetonide

AIMS

The aim of this study was to evaluate the functional and histopathologic changes in the levator palpebrae superioris and Müller muscles after subconjunctival injection of triamcinolone acetonide (TA) in rabbits.

METHODS

Twenty-four white New Zealand rabbits were divided into 2 groups. In group A, a subconjunctival injection of 0.5 mL TA (40 mg/mL) was administered to the right eye, whereas a normal saline injection of the same volume was administered to the left eye. In group B, the same procedures were done with a 1.0-mL injection of TA or normal saline into each eyelid. Follow-up was done to evaluate the histopathologic changes in the levator and Müller muscles, changes in the mean transectional area of Müller muscle, and changes in upper-lid height (marginal reflex distance 1) at 1, 2, 4, and 6 weeks after injection. Western blot analyses were used to determine the levels of myosin light chain phosphorylation and α-smooth muscle actin, which are related to the contractility of Müller muscle.

RESULTS

No specific changes in marginal reflex distance 1 were noted in either group A or B. No significant histopathologic changes were found in the levator muscles. However, significant thinning of Müller muscle were found, and myosin light chain phosphorylation and α-smooth muscle actin levels were decreased. This was consistent with the histologic changes of Müller muscle observed in rabbits that received a TA injection. These changes were reversible and influenced by the volume of the injection.

CONCLUSIONS

Subconjunctival injection of TA into the upper eyelids appears to be temporally influential on both the functional and histopathologic changes of Müller muscle in rabbits. This may be explained by the effect of improvement in lid retraction regardless of the minimal specific change observed in the levator muscle.

Periocular corticosteroid injections in uveitis: effects and complications

PURPOSE

To evaluate the benefits and complications of periocular depot corticosteroid injections in patients with ocular inflammatory disorders.

DESIGN

Multicenter, retrospective cohort study.

PARTICIPANTS

A total of 914 patients (1192 eyes) who had received ≥ 1 periocular corticosteroid injection at 5 tertiary uveitis clinics in the United States.

METHODS

Patients were identified from the Systemic Immunosuppressive Therapy for Eye Diseases Cohort Study. Demographic and clinical characteristics were obtained at every visit via medical record review by trained reviewers.

MAIN OUTCOME MEASURES

Control of inflammation, improvement of visual acuity (VA) to ≥ 20/40, improvement of VA loss attributed to macular edema (ME), incident cataract affecting VA, cataract surgery, ocular hypertension, and glaucoma surgery.

RESULTS

Among 914 patients (1192 eyes) who received ≥ 1 periocular injection during follow-up, 286 (31.3%) were classified as having anterior uveitis, 303 (33.3%) as intermediate uveitis, and 324 (35.4%) as posterior or panuveitis. Cumulatively by ≤ 6 months, 72.7% (95% CI, 69.1-76.3) of the eyes achieved complete control of inflammation and 49.7% (95% CI, 45.5-54.1) showed an improvement in VA from <20/40 to ≥ 20/40. Among the subset with VA <20/40 attributed to ME, 33.1% (95% CI, 25.2-42.7) improved to ≥ 20/40. By 12 months, the cumulative incidence of ≥ 1 visits with an intraocular pressure of ≥ 24 mmHg and ≥ 30 mmHg was 34.0% (95% CI, 24.8-45.4) and 15.0% (95% CI, 11.8-19.1) respectively; glaucoma surgery was performed in 2.4% of eyes (95% CI, 1.4-3.9). Within 12 months, among phakic eyes initially ≥ 20/40, the incidence of a reduction in VA to <20/40 attributed to cataract was 20.2% (95% CI, 15.9-25.6); cataract surgery was performed within 12 months in 13.8% of the initially phakic eyes (95% CI, 11.1-17.2).

CONCLUSIONS

Periocular injections were effective in treating active intraocular inflammation and in improving reduced VA attributed to ME in a majority of patients. The response pattern was similar across anatomic locations of uveitis. Overall, VA improved in one half of the patients at some point within 6 months. However, cataract and ocular hypertension occurred in a substantial minority.