Intraocular pressure after intravitreal injection of triamcinolone acetonide

Biomechanic, proteomic and miRNA transcriptional changes in the trabecular meshwork of primates injected with intravitreal triamcinolone

Although biomechanical changes of the trabecular meshwork (TM) are important to the pathogenesis of glucocorticoids-induced ocular hypertension (GC-OHT), there is a knowledge gap in the underlying molecular mechanisms of the development of it. In this study, we performed intravitreal triamcinolone injection (IVTA) in one eye of 3 rhesus macaques. Following IVTA, we assessed TM stiffness using atomic force microscopy and investigated changes in proteomic and miRNA expression profiles. One of 3 macaques developed GC-OHT with a difference in intraocular pressure of 4.2 mmHg and a stiffer TM with a mean increase in elastic moduli of 0.60 kPa versus the non-injected control eye. In the IVTA-treated eyes, proteins associated with extracellular matrix remodeling, cytoskeletal rearrangement, and mitochondrial oxidoreductation were significantly upregulated. The significantly upregulated miR-29b and downregulated miR-335-5p post-IVTA supported the role of oxidative stress and mitophagy in the GC-mediated biomechanical changes in TM, respectively. The significant upregulation of miR-15/16 cluster post-IVTA may indicate a resultant TM cell apoptosis contributing to the increase in outflow resistance. Despite the small sample size, these results expand our knowledge of GC-mediated responses in the TM and furthermore, may help explain steroid responsiveness in clinical settings.

The Evolution of Triamcinolone Acetonide Therapeutic Use in Retinal Diseases: From Off-Label Intravitreal Injection to Advanced Nano-Drug Delivery Systems

Ophthalmic drug delivery to the posterior segment of the eye has been challenging due to the complex ocular anatomy. Intravitreal injection of drugs was introduced to deliver therapeutic doses in the posterior segment. Different posterior segment diseases including age-related macular degeneration, diabetic macular edema, retinal vein occlusions, uveitis, and cystoid macular edema, among others, have been historically treated with intravitreal corticosteroids injections, and more recently with intravitreal corticosteroids drug implants. Triamcinolone acetonide (TA) is the most frequently used intraocular synthetic corticosteroid. Using nanoparticle-based TA delivery systems has been proposed as an alternative to intravitreal injections in the treatment of posterior segment diseases. From these novel delivery systems, topical liposomes have been the most promising strategy. This review is oriented to exhibit triamcinolone acetonide drug evolution and its results in treating posterior segment diseases using diverse delivery platforms.

IS A DECREASED NITRIC OXIDE CONCENTRATION AFTER TRIAMCINOLONE ACETONIDE INTRAVITREAL INJECTION ONE OF THE REASONS FOR INTRAOCULAR PRESSURE RISE?

Diabetic macular edema is the most common cause of vision loss in patients affected by diabetes mellitus. For eyes with persistent retinal thickening despite anti-VEGF therapy, treatment with intravitreal triamcinolone may be considered, especially in pseudophakic eyes. The aim of this study was to examine aqueous humor nitric oxide concentration changes in pseudophakic eyes with persistent diffuse diabetic macular edema after intravitreal injection of triamcinolone acetonide, as well as the potential impact of these changes on the intraocular pressure values. In 10 pseudophakic eyes with persistent diffuse diabetic macular edema, paracentesis of anterior chamber with aspiration of aqueous humor and nitric oxide concentration measurements were done on the day of the intravitreal application of 20 mg triamcinolone acetonide, and after 1, 3, 6 and 9 months. Also, we were recording intraocular pressure values before the intravitreal triamcinolone acetonide injection and during the next 9 months. One month after the intravitreal triamcinolone acetonide injection, we noticed a decrease of nitric oxide concentration (45.37±5.55 µmol/L) by 31.79% compared to the initial values (66.52±7.66 µmol/L). After that, nitric oxide concentrations began to rise slightly, and at the end of the ninth month the mean nitric oxide concentration was similar to that recorded at the beginning of the study. Intraocular pressure values had increasing trend one month after the intravitreal triamcinolone acetonide injection (23.70±4.08 mm Hg) compared to the initial values (16.21±1.55 mm Hg), but after nine months these values returned to normal levels. Decreased concentration of nitric oxide could be one of the reasons for increased intraocular pressure after intravitreal application of triamcinolone acetonide in the treatment of diffuse diabetic macular edema.

Steroid Treatment in Macular Edema: A Bibliometric Study and Visualization Analysis

The use of steroids to treat macular edema (ME) is a research hotspot in ophthalmology. We utilized CiteSpace and VOSviewer software to evaluate the Web of Science Core Collection publications and to build visualizing maps to describe the research progress in this topic. There were 3,252 publications for three decades during 1988–2021. The number of studies was low during the first 14 years but has risen consistently in the following two decades. The average publications per year were only 4.8 during 1988–2002, which jumped to 113 per year during 2003–2012, and 227 per year during 2013–2021. These publications came from 83 countries/regions, with the United States, Germany, and Italy leading positions. Most studies were published in Investigative Ophthalmology Visual Science, and Ophthalmology was the most cited journal. We found 9,993 authors, with Bandello F having the most publications and Jonas JB being the most frequently co-cited. According to our research, the most popular keyword is triamcinolone acetonide (TA). Macular edema, diabetic macular edema (DME), retinal vein occlusion (RVO), dexamethasone (DEX), fluocinolone acetonide (FA), and some other keywords were commonly studied in this field. In conclusion, the bibliometric analysis provides a comprehensive overview of steroid hotspots and developmental tendencies in the macular edema study. While anti-VEGF therapy is the first-line treatment for DME and RVO-induced macular edema, steroids implant is a valid option for these DME patients not responding to anti-VEGF therapy and non-DME patients with macular edema. Combined therapy with anti-VEGF and steroid agents is vital for future research.

Proteome Analysis of Urinary Biomarkers in a Bovine IRBP-Induced Uveitis Rat Model via Data-Independent Acquisition and Parallel Reaction Monitoring Proteomics

Uveitis, a group of intraocular inflammatory diseases, is one of the major causes of severe visual impairment among the working-age population. This study aimed to screen potential urinary biomarkers for uveitis based on proteome analysis. An experimental autoimmune uveitis (EAU) rat model induced by bovine interphotoreceptor retinoid-binding protein (IRBP) was used to mimic uveitis. In discovery phase, a total of 704 urinary proteins were identified via data-independent acquisition (DIA) proteomic technique, of which 76 were significantly changed (34, 36, and 37 on days 5, 8, and 12, respectively, after bovine IRBP immunization). Gene Ontology annotation of the differential proteins indicates that acute-phase response, innate immune response, neutrophil aggregation, and chronic inflammatory response were significantly enriched. Protein-protein interaction network indicates that these differential urinary proteins were biologically connected in EAU, as a group. In validation phase, 17 proteins having human orthologs were verified as the potential markers associated with uveitis by parallel reaction monitoring (PRM) targeted quantitative analysis. Twelve differential proteins changed even when there were no clinical manifestations or histopathological ocular damage. These 12 proteins are potential biomarkers for early diagnosis of uveitis to prevent the development of visual impairment. Five differential proteins changed at three time-points and showed progressive changes as the uveitis progressed, and another five differential proteins changed only on day 12 when EAU severity peaked. These 10 proteins may serve as potential biomarkers for prognostic evaluation of uveitis. Our findings revealed that the urinary proteome could sensitively reflect dynamic pathophysiological changes in EAU, and represent the first step towards the application of urinary protein biomarkers for uveitis.

Efficacy of Intravitreal Injection of Filtered Modified Low-Dose Triamcinolone Acetonide and Ranibizumab on Pseudophakic Cystoid Macular Edema

Purpose

To compare the visual and morphological effects between intravitreal injection of filtered modified 2 mg triamcinolone acetonide (TA) and 0. 5 mg ranibizumab in patients with pseudophakic cystoid macular edema (PCME).

Methods

A retrospective, interventional study was conducted from January 2015 to February 2020 involving patients with PCME after uneventful cataract surgery. A total of 25 patients (25 eyes) with PCME received an intravitreal injection of 0.22 μm filtered modified 2 mg TA, while 15 patients (15 eyes) received 0.5 mg ranibizumab injection. Central macular thickness (CMT), best-corrected visual acuity (BCVA), intraocular pressure (IOP), times of repeated injections, and other side effects were observed at 2 weeks, 1 month, 3 months, and 6 months after injection; then, the data were compared with preinjection information in each group and between the two groups.

Results

Both the TA and ranibizumab intravitreal injection can achieve improved BCVA and reduced CMT in patients with PCME (P < 0.05), with a trend toward greater improvement in the TA group, but the difference was only significant at 3 months (P < 0.05). IOP was in the normal range without any significant difference (P > 0.05). Thirty-three percent of patients in the ranibizumab group required repeated intravitreal injection compared to 4% in the TA group. Further stratified analysis showed that the better therapeutic effect of the TA group at 3 months after injection only existed in patients with diabetes mellitus (DM), while not in patients without DM. There was no repeat injection in the TA group and 12.5% in the ranibizumab group for patients without DM, while 16.7% in the TA group and 57.1% in the ranibizumab group required repeated injection for patients with DM, which had a significant difference (P < 0.05).

Conclusion

Intravitreal injection of filtered modified 2 mg TA is safe, effective, and an inexpensive alternative to antivascular endothelial growth factor (anti-VEGF) agents for patients with PCME, especially for patients concurrently with DM. A large number of clinical randomized controlled studies along with long-term follow-up observations are needed.

Identification of proteomic changes for dexamethasone-induced ocular hypertension using a tandem mass tag (TMT) approach

Glaucoma, characterized by ocular hypertension, is the second most common cause of vision loss worldwide. The potential mechanism, however, has yet to be elucidated. This study aimed to assess the proteomic changes in the trabecular meshwork (TM) in an observational animal model of Dexamethasone (DEX)-induced OHT. OHT was induced in Wistar rats by applying DEX topically to both eyes for 28 days. Intraocular pressure (IOP) was evaluated and TM protein expressions and protein identification were performed by a TMT-based method for comparing the changes in proteins between DEX-induced OHT and the control group. The results showed that average IOP was elevated significantly in rats of the DEX-induced OHT group compared to controls. Further, a total of 4,804 proteins in the control and DEX-induced OHT group were determined and 4,064 proteins were quantified via TMT proteomics. In total, 292 significantly abundant proteins (173 downregulated and 119 upregulated) were identified between the two groups. Proteins associated with vision, including Crystallin related proteins, filensin, rhodopsin, recoverin, phosducin were lowered in the DEX-induced OHT group relative to the control group. In summary, DEX induced extensive changes in the protein expression of TM tissue. These proteins were found to be candidate biomarkers for personalized treatment and diagnostic research in the future for improving visual health.

Beneficial effect of dimethyl fumarate on experimental autoimmune uveitis is dependent of pro-inflammatory markers immunomodulation

Autoimmune uveitis is an inflammatory disease of the eye and is one of the major causes of blindness worldwide. Experimental autoimmune uveoretinitis (EAU) constitutes an animal disease model of human endogenous uveitis. In our study, we investigated the immunomodulatory effect of dimethyl fumarate (DMF) using bovine retinal extract-induced uveitis in a Female Wistar rats. To evaluate the in vivo efficacy, Female Wistar rats were divided into seven experimental groups: control group (n = 5), consisting of non-immunized animals; Uveoretinitis (n = 5), and DMF/Uveoretinitis groups (n = 15), which received a subcutaneous injection of bovine retinal extract emulsified in complete Freund's adjuvant; MC group (n = 5), treated by daily intragastric administration of methylcellulose 0.08% in tap water; DMF group, consisting of control positive group, rats received daily oral gavage administration of 500 μL of dimethyl fumarate at 100 mg/Kg dissolved in 0.08% methylcellulose in tap water (n = 5). On day 14 post immunization, the rats were then euthanized and associated indications were investigated to evaluate the therapeutic efficacy. Nitric oxide (NO) and TNF-α were assessed in plasma. Meanwhile, eyes were collected for histological and immunohistochemical studies. The retinal expression of iNOS, CD68, CD20, CD25, CD4, and CD8 was examined. Interestingly, DMF enhanced a significant reduction of NO and TNF-α production in the treated group. This effect was strongly related to the histological structure of eyes improvement. In the same context, a significant decrease of iNOS, CD68, and CD20 expression and CD25 increase expression were reported in retinal tissue of DMF/Uveoretinitis group in comparison to the immunized group. Collectively, our results indicate that DMF treatment has a beneficial effect in experimental autoimmune uveoretinitis and could constitute a good candidate for monitoring an ocular inflammatory diseases.

Safety of intravitreal triamcinolone and its impact on optic nerve morphology in patients treated for diabetic macular edema

PURPOSE

To assess the impact of one intravitreal injection (IVT) of Triamcinolone Acetonide (TA) on intraocular pressure (IOP) and optic nerve structural parameters in patients treated for Diabetic Macular Edema (DME).

METHODS

This retrospective study included patients with DME that were naïve to intraocular steroids and underwent one IVT of TA of 4 mg/0.1 mL and age-matched controls with DME without criteria for IVT. Patients records were reviewed for IOP (at baseline and a month after IVT) and optic nerve parameters measured by optical coherence tomography (up to 6 months before and 6 months after IVT). Exclusion criteria included glaucoma and treatment with hypotensive agents.

RESULTS

Twenty-six eyes were included in the Control Group and 29 in the IVT Group, with a mean age of 65.10 ± 10.08 and 67.30 ± 4.71 years, respectively (p = 0.06). At baseline, IOP and optic nerve measurements were equivalent between groups (p > 0.05). One month after IVT, mean IOP measurements in IVT Group were higher than those of controls (17.84 ± 4.50 vs 11.59 ± 3.09 mmHg, p < 0.001). Ocular hypertension (OHT) developed in 17.24% of cases and reversed with topical medication. After one IVT, vertical cup/disc ratio was higher (0.57 ± 0.25 vs 0.60 ± 0.14, p = 0.04) and retinal nerve fiber layer thickness was globally lower (mean: 91.03 ± 4.25 vs 81.33 ± 19.10 µm, p = 0.001) in the IVT Group.

CONCLUSION

Our results confirmed that intravitreal TA results in IOP increase. This seems to negatively affect optic nerve morphology, even in patients without OHT or adequately treated with hypotensive agents.

Recent trends in drug-delivery systems for the treatment of diabetic retinopathy and associated fibrosis

Diabetic retinopathy is a frequent microvascular complication of diabetes and a major cause of visual impairment. In advanced stages, the abnormal neovascularization can lead to fibrosis and subsequent tractional retinal detachment and blindness. The low bioavailability of the drugs at the target site imposed by the anatomic and physiologic barriers within the eye, requires long term treatments with frequent injections that often compromise patient's compliance and increase the risk of developing more complications. In recent years, much effort has been put towards the development of new drug delivery platforms aiming to enhance their permeation, to prolong their retention time at the target site and to provide a sustained release with reduced toxicity and improved efficacy. This review provides an overview of the etiology and pathophysiology of diabetic retinopathy and current treatments. It addresses the specific challenges associated to the different ocular delivery routes and provides a critical review of the most recent developments made in the drug delivery field.

OCULAR HYPERTENSION AFTER INTRAVITREAL INJECTION OF 2-MG TRIAMCINOLONE

PURPOSE

To report the incidence and course of ocular hypertension after intravitreal injection of 2-mg triamcinolone acetonide (IVT).

METHODS

In a retrospective, consecutive series, all patients receiving 2-mg IVT at a single institution between March 1, 2012, and March 1, 2017, with a minimum of 3-month follow-up were reviewed. Ocular hypertension was defined as an intraocular pressure (IOP) measurement over 24 mmHg at any follow-up visit after IVT. Patients receiving topical, periocular, or intravitreal corticosteroid other than 2-mg IVT were excluded.

RESULTS

A total of 106 eyes in 100 patients receiving at least one injection of 2-mg IVT were included. Eyes received an average of 2.9 injections (range 1-17), and average patient follow-up was 15.1 months (range 3.0-52.5 months). A total of 14 eyes (13.2%) in 14 patients developed ocular hypertension after a median of 1.5 injections (range 1-9) with an average peak IOP of 29 mmHg (range 25-38 mmHg). Overall, a total of 11 eyes (10.4%) had an IOP elevation ≥10 mmHg above baseline at any point after first IVT. In all cases of ocular hypertension, IOP was successfully managed with observation or topical IOP-lowering medication alone; no patients required surgical intervention.

CONCLUSION

Ocular hypertension developed in 13.2% of eyes receiving intravitreal injection of 2-mg triamcinolone acetonide. Incidence of ocular hypertension after 2-mg IVT compares favorably with other intravitreally administered corticosteroids.

Corticosteroids in ophthalmology: drug delivery innovations, pharmacology, clinical applications, and future perspectives

Corticosteroids remain the mainstay of the treatment for various ocular conditions affecting the ocular surface, anterior and posterior segments of the eye due to their anti-inflammatory, anti-oedematous, and anti-neovascularization properties. Prednisolone, prednisolone acetate, dexamethasone, triamcinolone acetonide, fluocinolone acetonide, and loteprednol etabonate are amongst the most widely used ophthalmic corticosteroids. Corticosteroids differ in their activity and potency in the eye due to their inherent pharmacological and pharmaceutical differences. Different routes and regimens are available for ocular administration of corticosteroids. Conventional topical application to the eye is the route of choice when targeting diseases affecting the ocular surface and anterior segment, while periocular, intravitreal, and suprachoroidal injections can be potentially effective for posterior segment diseases. Corticosteroid-induced intraocular pressure elevation and cataract formation remain the most significant local risks following topical as well as systemic corticosteroid administration. Invasive drug administration via intracameral, subconjunctival, and intravitreal injection can enhance ocular bioavailability and minimize dose and dosing frequency of administration, yet may exacerbate ocular side effects of corticosteroids. This review provides a critical appraisal of the ophthalmic uses of corticosteroid, routes of administration, drug delivery fundamentals and novel ocular implantable steroid delivery systems, factors influencing side effects, and future perspectives for ocular corticosteroid therapy.

Ocular Hypertension Following Intravitreal Injection of 0.7mg Dexamethasone Implant versus 2mg Triamcinolone

Background: To compare the incidence and outcomes of ocular hypertension (OHT) after intravitreal injection of 0.7 mg dexamethasone (DEX) and 2 mg triamcinolone acetonide (IVT).Methods: In a single-center, retrospective comparative case series, all patients with at least 3 months follow-up receiving 2 mg IVT 3/1/2012 - 3/1/2017 or 0.7 mg dexamethasone 10/1/2014 - 3/1/2017 were included. Ocular hypertension was defined as an intraocular pressure (IOP) ≥ 25 mmHg. Patients with a minimum of 3 months follow-up were included. Patients receiving any other form of topical, oral, or intravitreal steroid were excluded.Results: 106 eyes in 100 patients receiving IVT and 114 eyes in 102 patients receiving DEX were included. The mean number of injections was 2.9 for patients receiving IVT and 2.4 for patients receiving DEX (p = .11). Fourteen eyes (13.2%) in 14 patients receiving IVT developed OHT compared to 17 eyes (15.1%) in 15 patients receiving DEX (p = .85). All cases of OHT were managed with IOP lowering drops or observation alone.Conclusions: Rates of ocular hypertension following 2 mg IVT and DEX are similar. All patients developing OHT were successfully managed without surgical intervention.

Finite element analysis of cornea deformation and curvature change during the keratoplasty suturing process

Keratoplasty, which is cornea transplant surgery, is one of the treatment methods for patients with turbidity or keratitis. Recently, keratoplasty using a surgical robot was studied to increase precision. In this study, the effect of surgical factors on the deformation and curvature of the cornea were analyzed in order to improve the accuracy of keratoplasty and derive the optimal surgical factors using finite element method (FEM). Suturing tension and depth were selected as surgical factors. An FEM model, a constitutive equation, and boundary conditions were determined using experiments and reference data. Suturing tension significantly impacted deformation and curvature change, and suturing depth affected the position of the thread-cornea contact point. Both factors have a significant impact on a focal point in the retina and the patient's visual acuity after keratoplasty.

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.

Evaluation of optic nerve head blood flow in response to increase of intraocular pressure

The time course of the changes in the optic nerve head (ONH) blood flow in response to changes in the ocular perfusion pressure (OPP) induced by an artificial elevation of the intraocular pressure (IOP) has not been determined. We measured the blood flow, represented by the mean blur rate (MBR), on the ONH determined by laser speckle flowgraphy. The MBR was determined before, during, and after the IOP was elevated by 20 or 30 mmHg by pressure applied on the eye by an ophthalmodynamometer in a total of 27 healthy eyes. For an IOP elevation of 20 mmHg, the percentage reduction in the MBR-vessel was −24.7%, and in the MBR-tissue was −16.0% (P < 0.001). For an IOP elevation of 30 mmHg, the percentage reduction of the MBR-vessel was −35.3% and the MBR-tissue was −24.7% (P < 0.001). During the 30 mmHg IOP elevation for 10 minutes, both the MBR-vessel and MBR-tissue began returning to the baseline level from 1 minute after the beginning of the IOP elevation (P < 0.01, P < 0.05, respectively) and continued returning during the 10 minutes IOP elevation (P < 0.001, P < 0.01, respectively). We conclude that the ONH can autoregulate its blood flow in response to experimental changes in OPP induced by IOP elevations.

Retina and glaucoma: surgical complications

Background

The close structural and microcirculatory co-relation between anterior and posterior segments of eye make them very vulnerable to complications when one of them is affected surgically. With the advent of anti-fibrotic agents in the management of glaucoma, the rates of vitreoretinal complications have become more frequent.

Main body

Common retinal complications after glaucoma surgeries include choroidal detachment; ocular decompression retinopathy; haemorrhagic choroidal detachment; hypotony maculopathy; malignant glaucoma; vitreous haemorrhage; bleb endophthalmitis; retinal detachment. Similarly, intraocular pressure rise is often noted after scleral buckle; pars plana vitrectomy; intravitreal gas injection; silicone oil injection; intravitreal steroid injection.

Conclusion

The article provides some insight into some of the complications after glaucoma and retina surgeries, including the pathogenetic mechanisms behind each complication and available management options.

Raised intraocular pressure following Intravitreal Triamcinolone Acetonide in diabetic versus non-diabetic patients

OBJECTIVE

To determine the frequency of an increase in intraocular pressure (IOP) after intravitreal triamcinolone acetonide (IVTA) in diabetic versus non-diabetic patients with various chorio-retinal disorders.

METHODS

This prospective, interventional comparative case series was conducted at Isra Postgraduate Institute of Ophthalmology, Al-Ibrahim Eye Hospital, Karachi from May 2012 to April 2014. Two hundred thirty seven eyes of 180 patients were enrolled with 90 patients each in diabetic and non-diabetic group, requiring IVTA. IVTA 4mg/0.1ml was injected and IOP was measured at one week, one month, three months and six months in both groups of patients.

RESULTS

In diabetic group, 43 patients were male (47.8%) and 47 were female (52.2%), while in non-diabetic group, 56 (62.2%) patients were male and 34 (37.8%) were female. Mean age of patients in diabetic group was 52.21 ± 9.6 years and in non-diabetic group was 51.13 ± 10.75 years. The mean preoperative IOP was 13.6 ± 2.8 mmHg and 14.1 ± 2.4 mmHg in diabetic and non-diabetic group respectively. In diabetic group, mean (±SD) IOP was 16.4 ±4.9 mmHg, 14.6 ±3.6 mmHg, 17.6 ± 9.7 mmHg and 15.5 ± 7.09 mmHg at one week, one month, three months and 6 months post injection. While in non-diabetic cases, mean (±SD) IOP was 14.8 ± 3.33 mmHg, 15.9 ± 4.2 mmHg, 15.5 ± 4.2 mmHg and 14.1 ± 3.2 mmHg at one week, one month, three months and 6 months follow up. The raised IOP was observed in 117 eyes (49%) in both groups of patients, with 78 eyes (65%) in diabetic group and 39 eyes (33%) in non-diabetic group.

CONCLUSIONS

After IVTA, an IOP rise was observed more in diabetics than non-diabetic patients.

Verteporfin Therapy and Triamcinolone Acetonide: Convergent Modes of Action for Treatment of Neovascular Age-Related Macular Degeneration

PURPOSE

Choroidal neovascularization associated with age-related macular degeneration is the primary cause of blindness in the elderly in developed countries, due to a number of pathogenic effects, including angiogenesis, cell-mediated inflammation, leukocyte adhesion and extravasation, and matrix remodeling.

METHODS

By producing photochemical effects at the site of target tissue (lesion), photodynamic therapy (PDT) can induce vascular damage and blood flow stasis, leading to occlusion of vascularization and lesion leakage.

RESULTS

PDT with verteporfin (Visudyne, Novartis) has been shown to be safe and effective in reducing the risk of vision loss in patients with classic containing subfoveal CNV and occult with no classic CNV. However, in predominantly occult CNV, the treatment may be most effective in smaller lesions, and less in larger lesions. Most important, visual acuity rarely is improved.

CONCLUSIONS

Pilot studies and large case series suggest that a combination of PDT and intravitreal triamcinolone acetonide has the potential to improve visual outcomes and reduce the need for additional treatments. Randomized, prospective clinical trials are underway to confirm the efficacy and safety of this novel treatment modality.

Argon Laser Trabeculoplasty in Triamcinolone Acetonide Induced Ocular Hypertension Refractory to Maximal Medical Treatment

Purpose

To report two cases of intraocular hypertension after intravitreal injection of triamcinolone acetonide (iTAA) that were refractory to maximal medical therapy and were successfully treated with argon laser trabeculoplasty (ALT).

Methods

Two patients with history of primary open angle glaucoma were treated with intravitreal injection of triamcinolone acetonide for chronic macular edema secondary to branch retinal vein occlusion. Both patients (Case 1 after 2 months and Case 2 after 5 days) developed intraocular hypertension that did not respond to maximal medical therapy. Despite medical therapy, intraocular pressure (IOP) was 45 mmHg in Case 1 and between 34 and 37 mmHg in Case 2. ALT was performed in the inferior 180° angle using the following parameters: 50 μm size, 700 mW, 0.50 sec, 100 spots.

Results

In both patients IOP returned to normal level a few days after ALT.

Conclusions

ALT seems to be effective at reducing IOP in patients with intraocular hypertension secondary to iTAA that does not respond to maximal medical treatment.

Intravitreal Triamcinolone Acetonide for Treatment of Central Retinal Vein Occlusion

PURPOSE

To evaluate the effect of intravitreal triamcinolone acetonide on visual acuity and intraocular pressure in patients with central retinal vein occlusion.

METHODS

This prospective comparative non-randomized clinical interventional study included 32 patients (33 eyes) with central retinal vein occlusion. The study group (12 patients; 13 eyes) received an intravitreal injection of about 20 mg of triamcinolone acetonide. The control group (20 patients) did not receive any treatment. Mean follow-up was 10.1+/-8.6 months in the study group and 6.0+/-5.2 months in the control group.

RESULTS

In the study group, mean visual acuity increased significantly (p=0.018) from 0.11+/-0.11 preoperatively to a best visual acuity during follow-up of 0.18+/-0.15. An improvement in visual acuity by at least 2 Snellen lines and 3 Snellen lines, respectively, was found for 8 (62%) eyes and 5 (38) eyes. Visual acuity measurements determined 1 month (p=0.038) and 3 months (p=0.046) after the injection were significantly higher than the baseline values. Increase in visual acuity was higher in the non-ischemic subgroup than in the ischemic subgroup. In the control group, baseline visual acuity and best visual acuity during the followup did not vary significantly (p=0.33). Visual acuity decreased significantly (p=0.007) towards the end of the follow-up. Comparing study group and control group, gain in visual acuity was significantly (p=0.01) higher in the study group. In the study group, intraocular pressure increased significantly (p=0.018) from 14.4+/-3.9 mmHg to a mean maximal value of 21.6+/-9.2 mmHg (range, 10-44 mmHg), and re-decreased (p=0.012) towards the end of follow-up to 15.3+/-5.1 mmHg (range, 10-21 mmHg).

CONCLUSIONS

Intravitreal triamcinolone acetonide temporarily increases visual acuity in central retinal vein occlusion. It is accompanied by an increase in intraocular pressure.

Intravitreal Triamcinolone Acetonide as Primary Treatment for Diffuse Diabetic Macular Edema: A Prospective Noncomparative Interventional Case Series

Purpose

To evaluate the efficacy and safety of one intravitreal injection of 25 mg of triamcinolone acetonide as primary treatment for diffuse diabetic macular edema.

Methods

Intravitreal triamcinolone acetonide injection was performed in 30 eyes with previously untreated diabetic macular edema. The main outcome measures were logMAR visual acuity (VA) and central macular thickness (CMT) at 1, 3, and 6 months. A secondary outcome was intraocular pressure progression.

Results

Visual acuity results for 30 eyes that had a follow-up of at least 6 months are presented. Twenty of them were followed up to 10.1 ±2.38 months. Preoperatively, VA was 0.54±0.27. At 1, 3, and 6 months follow-up, VA was 0.44±0.29 (p=0.001), 0.43±0.28 (p=0.001), and 0.45±0.29 (p=0.006), respectively. Preoperatively, CMT was 417.3±143.5 μm. At 1, 3, and 6 months follow-up, CMT was 277.3 +74.0 μm (p<0.0001), 279.6±94.4 μm (p<0.0001), and 297.07±114.87 μm (p=0.002), respectively. For the 20 eyes with a follow-up of 10.1±2.38 months, VA was 0.5±0.25 and 0.50±0.32 at baseline and at the last follow-up visit, respectively (p>0.05). Preoperatively, intraocular pressue (IOP) was 15.13±1.48 mmHg. IOP was 18.26±2.71 mmHg, 20.07±4.27 mmHg, and 20.4±6.18 mmHg, at 1, 3, and 6 months, respectively (p<0.0001). Four eyes underwent uncomplicated filtrating surgery for intractable glaucoma.

Conclusions

Intravitreal triamcinolone as primary treatment effectively increases VA and reduces CMT due to diffuse diabetic macular edema. Longer follow-up and randomized clinical trial are war ranted. Safety results highlight the need to further study the relationship between triamcinolone and intraocular pressure.

Prospective Evaluation of Intravitreal Triamcinolone Acetonide Injection in Macular Edema Associated with Retinal Vascular Disorders

Purpose

To evaluate the effect of intravitreal triamcinolone acetonide on visual acuity and macular thickness using optical coherence tomography (OCT) in macular edema associated with various retinal vascular disorders.

Methods

This prospective nonrandomized clinical interventional study included 81 eyes (76 patients) comprised of Group I, 57 eyes (51 patients) with diabetic macular edema; Group II, 10 eyes (10 patients) with branch retinal vein occlusion; and Group III, 13 eyes (13 patients) with central retinal vein occlusion. All eyes received an intravitreal injection of 4 mg triamcinolone acetonide (with the solvent) in the operation theater under sterile conditions.

Results

Mean preinjection central macular thickness was 531.84±132 μm in Group I, 458.4±149 μm in Group II, and 750.81±148 μm in Group III. All groups showed a statistically significant decrease in mean central macular thickness at 1 month (300.7±119 μM in Group I, 218.2±99 μm in Group II, and 210.5 ±56 μm in Group III) and 3 months (253.19±109 μm in Group I, 187±47 μm in Group II, and 182±50 μm in Group III) after injection (p<0.05). Mean follow-up was 22±2.4 weeks. Mean visual acuity increased in all three groups (preoperative visual acuity in Group I, 1.2±0.4 logMAR units; Group II, 1.24±0.5 logMAR units; Group III, 1.1 ±0.4 logMAR units; 1 month postinjection in Group I, 0.88±0.3 logMAR units; Group II, 0.67±0.3 logMAR units; Group III, 0.86±0.4 logMAR units; 3 months postinjection in Group I, 0.84±0.4 logMAR units; Group II, 0.59±0.3 logMAR units; Group III, 0.82±0.5 logMAR units) (p<0.05). Forty-one eyes completed 6 months and 20 eyes completed 9 months follow-up. Twelve of 20 (41%) eyes in Group I, 2/6 (33%) eyes in Group II, 3/6 (50%) eyes in Group III, and 8/15 (53%) eyes in Group I, 1/3 (33%) eyes in Group II, and 2/2 (100%) eyes in Group III developed recurrence of macular edema with worsening of visual acuity at 6 and 9 months, respectively. Thirty-three (40.7%) eyes developed IOP elevation (at least one reading > 24 mmHg). One eye developed infective endophthalmitis.

Conclusions

Intravitreal injection of triamcinolone acetonide may be considered as an effective treatment for reducing macular thickening due to diffuse diabetic macular edema, venous occlusion associated macular edema, and may result in increase in visual acuity at least in the short term. Further follow-up and analysis is required to demonstrate its long-term efficacy.

Comparison of treatment response to intravitreal injection of triamcinolone, bevacizumab and combined form in patients with central retinal vein occlusion: A randomized clinical trial

BACKGROUND

Central retinal vein occlusion (CRVO), is the second-most common disorder after diabetic retinopathy that threatens the vision related to retinal vessels. One of the main reasons of vision loss is CRVO in acute and chronic forms.

OBJECTIVE

The aim of this study was to investigate the response to intravitreal injection of triamcinolone, bevacizumab, and a combined form in patients with CRVO.

METHODS

This study was a double-blinded randomized clinical trial conducted on patients with CRVO who were referred to the ophthalmology clinic of Urmia Imam Khomeini Hospital from May 2015 to May 2016. In total, ninety patients were divided into three groups using random numbers table. The first group received intravitreal triamcinolone acetonide (IVT) for treatment of macular edema due to CRVO, the second group received intravitreal bevacizumab (IVB) and the third group received a combination of IVT and IVB. The best corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded and analyzed using optical coherence tomography system.

RESULTS

In this study a total of 90 eyes were studied, 41 case (45.55%) were male and 49 cases (54.44%) were female. The mean age of patients was 68.41±8.32 years. The mean score of final visual acuity was 0.293±0.11 in the IVT group, 0.25±0.10 in the IVB group and 0.48±0.15 in the IVB+IVT group. The differences between groups considering final visual acuity was significant (p<0.001). The mean thickness of final macular was 383.33±97.70 micrometer in IVT group, 386.33±136.79 micrometers in IVB group and 307.33±110.79 micrometers in IVT+IVB group which were significant (p=0.014).

CONCLUSION

Using a combination of bevacizumab and triamcinolone in the treatment of central retinal vein occlusion compared with using each of them separately, had a better result and can be used as a solution in this disease.

TRIAL REGISTRATION

The trial was registered at the Thai Registry of Clinical Trials (http://www.clinicaltrials.in.th) with the TCTR ID: TCTR20170612005.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

Quantitative evaluation of hard exudates in diabetic macular edema after short-term intravitreal triamcinolone, dexamethasone implant or bevacizumab injections

Background

To quantitatively compare short-term hard exudates (HEs) alteration in patients with diabetic macular edema (DME) after intravitreal triamcinolone, dexamethasone implant or bevacizumab injections.

Methods

This retrospective study enrolled DME eyes with HEs that underwent a single-dose intravitreal injection of triamcinolone (25 eyes), dexamethasone implant (20 eyes), or three monthly injections of bevacizumab (25 eyes) and completed at least three months of follow-up. All patients were examined before and after 1, 2 and 3 months of injections. Using color fundus photographs, the amount of HEs was quantified by two masked graders. The difference in HEs area between baseline and each follow-up visit was compared among the three groups.

Results

After three months, HEs area was reduced to 52.9 ± 4.21% (P < 0.001) in the triamcinolone group, 63.6 ± 6.08% (P = 0.002) in the dexamethasone implant group, and 85.2 ± 5.07% (P = 0.198) in the bevacizumab group. A significant reduction in HEs appeared at one month in the triamcinolone group (53.5 ± 4.91%, P < 0.001) and at two months in the dexamethasone implant group (70.1 ± 5.21%, P = 0.039).

Conclusions

Our study suggests intravitreal steroids (triamcinolone, dexamethasone implants) significantly reduce HEs in DME patients on short-term follow-up, whereas intravitreal bevacizumab does not. Therefore, intravitreal steroids may be useful in DME with HEs in the fovea.

Vessel diameter study: intravitreal vs posterior subtenon triamcinolone acetonide injection for diabetic macular edema

PurposeTo detect and compare the vessel diameter effect of intravitreal vs subtenon injection of triamcinolone for diabetic macular edema (DME).MethodsSixty patients with DME who underwent triamcinolone injection either intravitreally (N=30) or under the tenon capsule (N=30) were included. Non-injected fellow eyes served as control. The main outcome measures were central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery-vein ratio (AVR).ResultsIn the intravitreal group, pre-injection mean CRAE (147.07 μ) decreased to 141.03 μ at 1 week and to 139.43 μ at 1 month (P<0.001) while baseline CRVE (209.61 μ) decreased initially to 198.85 μ at 1 week then to 198.49 μ at 1 month (P<0.001). In the subtenon group, pre-injection CRAE (152.18 μ) decreased to 149.49 μ at 1 week and to 147.47 μ at 1 month (P=0.017), while baseline CRVE (215.60 μ) decreased initially to 208.69 μ at 1 week then to 207.25 μ at 1 month (P=0.003). Pre-injection AVR values did not change at 1 week and at 1 month in both injection groups (P=0.66 and P=0.196, respectively). In the control group, none of the 3 parameters changed throughout the study period compared to the baseline (P>0.28).ConclusionIn eyes with DME, both intravitreal and subtenon triamcinolone injection led to a significant constriction of retinal arteries and veins.

Clinical Outcomes of Intravitreal Preservative-Free Triamcinolone Preparation (Triesence®) for Cystoid Macular Oedema and Inflammation in Patients with Uveitis

PURPOSE

To assess the outcomes of intravitreal benzyl alcohol-free triamcinolone acetonide suspension in uveitis-related macular oedema.

METHODS

Single-center retrospective cohort study of 66 injections to 44 eyes of 40 patients. Uveitis diagnosis, systemic and local therapy, intraocular pressure (IOP), central retinal thickness (CRT), number of injections, time to re-injection and side-effects were noted during 6-months minimum follow-up.

RESULTS

Sixty eight percent of eyes received a single injection. 18% required 2 injections, and 13% received ≥3 injections with mean time to second and third injections of 25.5 and 52.7 weeks, respectively. 90% of injections were unilateral. Mean CRT reduced, and by 12-weeks visual acuity improvement >0.3logMar was achieved in 46%. Cataract progression (47%) and IOP>21 mmHg (45%) were the commonest adverse events.

CONCLUSION

Preservative-free triamcinolone is an additional option for uveitis-related macular oedema, particularly in unilateral cases, with favorable CRT and visual outcomes. Repeat injections may be necessary, and the period of efficacy varies between eyes.

Ultrasound-enhanced penetration through sclera depends on frequency of sonication and size of macromolecules

We previously employed ultrasound as a needleless approach to deliver macromolecules via the transscleral route to the back of the eye in live animals (Suen et al., 2013). Here, we investigated the nature of the ultrasound-enhanced transport through sclera, the outermost barrier in the transscleral route. Thus, the possible role of cavitation from ultrasound was explored; its effect during and after sonication on scleral penetration was measured; and the dependence on the size of macromolecules was determined. We applied ultrasound frequency from 40kHz to 3MHz at I_SATA (spatial-average-temporal-average intensity) of 0.05W/cm² to fresh rabbit sclera ex vivo. Fluorescent dextran of size 20kDa to 150kDa was used as macromolecular probes. We measured the distance of penetration of the probes through the sclera over 30s during sonication and over 15min after sonication from cryosectioned tissue images. Deeper penetration in the sclera was observed with decreasing frequency. The presence of stable cavitation was further verified by passive acoustic detection. The effect during sonication increased penetration distance up to 20 fold and was limited to macromolecular probes ≤70kDa. The effect post sonication increased penetration distance up to 3 fold and attributed to the improved intrasscleral transport of macromolecules ≥70kDa. Post-sonication enhancement diminished gradually in 3h. As the extent of cavitation increased with decreasing frequency, the trend observed supports the contribution of (stable) cavitation to enhancing transport through sclera. Effect during sonication was attributed to flow associated with acoustic microstreaming. Effect post sonication was attributed to the temporary increase in scleral permeability. Flow-associated effect was more pronounced but only applied to smaller macromolecules.

Outcome of primary trabeculotomy ab interno (Trabectome) surgery in patients with steroid-induced glaucoma

To determine the efficacy and safety of Trabectome surgery on patients with steroid response, ranging from ocular hypertension refractory to maximal medical therapy to the development of steroid-induced glaucoma.A nonrandomized, nonblinded, retrospective study of 20 subjects with steroid response was conducted. All 20 eyes underwent Trabectome surgery alone. Nine subjects had steroid response with unremarkable visual field, 3 had mild steroid-induced glaucoma, and 8 had advanced steroid-induced glaucoma. Outcome measures included intraocular pressure (IOP), number of glaucoma medications, need for secondary glaucoma surgery, and steroid regimen. Mann-Whitney U test was used to compare postoperative IOP and number of medications to preoperative IOP and number of medications. Kaplan-Meier was used for survival analysis, and success was defined as: IOP reduced by 20% or more on any 2 consecutive visits after 3 months; IOP ≤21 mm Hg on any 2 consecutive visits after 3 months; and no secondary glaucoma surgery.The average preoperative IOP was 33.8 ± 6.9 mm Hg and average preoperative glaucoma medication usage was 3.85 ± 0.75 medications. At 12 months, the IOP was reduced to 15.00 ± 3.46 mm Hg (P = 0.03) and glaucoma medication was reduced to 2.3 ± 1.4 (P < 0.01). The survival rate at 12 months was 93%. At 12 months, 10 patients were continued on their preoperative steroid treatments, 5 were on tapered steroid treatments, and 5 had ceased steroid treatments entirely. One patient required secondary glaucoma surgery (glaucoma drainage device). No other complications were noted.The Trabectome procedure is safe and highly effective for steroid-response glaucoma, even in the context of continued steroid treatment.

Moving Past Anti-VEGF: Novel Therapies for Treating Diabetic Retinopathy

Diabetic retinopathy is the leading cause of blindness in working age adults, and is projected to be a significant future health concern due to the rising incidence of diabetes. The recent advent of anti-vascular endothelial growth factor (VEGF) antibodies has revolutionized the treatment of diabetic retinopathy but a significant subset of patients fail to respond to treatment. Accumulating evidence indicates that inflammatory cytokines and chemokines other than VEGF may contribute to the disease process. The current review examines the presence of non-VEGF cytokines in the eyes of patients with diabetic retinopathy and highlights mechanistic pathways in relevant animal models. Finally, novel drug targets including components of the kinin-kallikrein system and emerging treatments such as anti-HPTP (human protein tyrosine phosphatase) β antibodies are discussed. Recognition of non-VEGF contributions to disease pathogenesis may lead to novel therapeutics to enhance existing treatments for patients who do not respond to anti-VEGF therapies.

Elevated Intraocular Pressure After Intravitreal Steroid Injection in Diabetic Macular Edema: Monitoring and Management

INTRODUCTION

With the increasing use of intravitreal administration of corticosteroids in macular edema, steroid-induced intraocular pressure (IOP) rise is becoming an emergent issue. However, for patients in whom intravitreal steroids are indicated, there are no specific recommendations for IOP monitoring and management after intravitreal administration of corticosteroids.

METHOD

An expert panel of European ophthalmologists reviewed evidence on corticosteroid-induced IOP elevation. The objective of the panel was to propose an algorithm based on available literature and their own experience for the monitoring and management of corticosteroid-induced IOP elevation, with a focus on diabetic patients.

RESULTS

Data from trials including diabetic patients with a rise of IOP after intravitreal steroid administration indicate that IOP-lowering medical treatment is sufficient for a large majority of patients; only a small percentage underwent laser trabeculoplasty or filtering filtration surgery. A 2-step algorithm is proposed that is based on the basal value of IOP and evidence for glaucoma. The first step is a risk stratification before treatment. Patients normotensive at baseline (IOP ≤ 21 mmHg), do not require additional baseline diagnostic tests. However, patients with baseline ocular hypertension (OHT) (IOP > 21 mmHg) should undergo baseline imaging and visual field testing. The second step describes monitoring and treatment after steroid administration. During follow-up, patients developing OHT should have baseline and periodical imaging and visual field testing; IOP-lowering treatment is proposed only if IOP is >25 mmHg or if diagnostic tests suggest developing glaucoma.

CONCLUSION

The management and follow-up of OHT following intravitreal corticosteroid injection is similar to that of primary OHT. If OHT develops, IOP is controlled in a large proportion of patients with standard IOP treatments. The present algorithm was developed to assist ophthalmologists with guiding principles in the management of corticosteroid-induced IOP elevation.

FUNDING

Alimera Sciences Limited.

Intraocular pressure elevation after intravitreal triamcinolone acetonide injection: a Meta-analysis

AIM

To report on intraocular pressure (IOP) after intravitreal injections of triamcinolone acetonide.

METHODS

Systematic literature review of studies that investigated the effects of an injection of triamcinolone intravitreal triamcinolone acetonide on IOP was conducted according to the Cochrane Collaboration methodology and the reported effects have been analyzed with Meta-analysis.

RESULTS

We found that the IOP follows an inverted-U shape pattern over time starting with an average value of 14.81±1.22 mm Hg before the injection, rising to a maximum of 19.48±2.15 mm Hg after one month of injection and falling down to 16.16±1.92 mm Hg after 6mo. Moreover, country of study, age, previous history of glaucoma and gender compositions matter for cross-study were different in reported IOP changes.

CONCLUSION

Our findings may be helpful in determining pressure elevation risk of intravitreal triamcinolone acetonide therapy as well as comparing it with those of more recent therapies such as the anti-vascular endothelial growth factor agents.

The combination of phacoemulsification surgery and intravitreal triamcinolone injection in patients with cataract and diabetic macular edema

PURPOSE

To assess the safety and efficiency of combined phacoemulsification (PHACO) surgery and intravitreal triamcinolone (IVTA) injection with or without macular grid laser photocoagulation in patients with cataract and diabetic macular edema.

MATERIAL AND METHODS

This prospective study included 41 eyes of 36 diabetic patients with cataract and coexisting clinically significant macular edema (CSME). After PHACO and IVTA injection eyes were divided into two groups: the laser and IVTA group (Group 1) and only IVTA group (Group 2). Preoperative and postoperative best corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) were recorded. Paired sample t-test was used to compare data in the groups and C square test for qualitative variables.

RESULTS

Postoperative BCVA was significantly higher than the initial BCVA during the follow-up period in both groups (p < 0.01). The BCVA 6 months after surgery was significantly higher in group 1 than in group 2 (p < 0.01). There was no statistically significant difference in IOP between two groups preoperatively and postoperatively during the follow-up period (p > 0.05). There was no statistically significant difference between both groups in mean CMT preoperatively and 2nd week, 2nd month and 3rd month after surgery (p > 0.05). The mean CMT 6 months after surgery was statistically significantly lower in group 1 than in group 2 (p < 0.01).

CONCLUSIONS

PHACO surgery combined with IVTA injection improves BCVA and provides a decrease in CMT in diabetic patients with CSME. Additional macular grid laser photocoagulation after surgery helps to preserve this improvement in BCVA and decrease in CMT.

Side-effects of anti-inflammatory therapy in uveitis

Uveitis is a group of inflammatory ocular conditions that cause significant visual morbidity around the world. Many of the cases of blindness secondary to uveitis can be avoided with adequate and aggressive management of the intraocular inflammation. Steroids have been utilized in the treatment of noninfectious uveitis for more than 60 years, but their chronic use is associated with severe ocular and systemic side-effects. Ophthalmologists are often not familiar with the systemic steroid-sparing agents available for the management of ocular inflammation and depend primarily on the use of corticosteroids. In this article, we review the most common agents utilized in the treatment of uveitis and their side-effect profiles.

Complications of intravitreal injections in patients with diabetes

Intravitreal injections for the treatment of retinal disorders and intraocular infection have become a common ophthalmic procedure, and injections of anti-vascular endothelial growth factor agents or steroids are frequently performed for the treatment of diabetic macular edema or other diabetic vascular pathology. Diabetic patients may be at higher risk of adverse events than non-diabetic individuals given frequent systemic co-morbidities, such as cardiovascular and renal disease, susceptibility to infection, and unique ocular pathology that includes fibrovascular proliferation. Fortunately, many associated complications, including endophthalmitis, are related to the injection procedure and can therefore be circumvented by careful attention to injection techniques. This review highlights the safety profile of intravitreal injections in patients with diabetes. Although diabetic patients may theoretically be at higher risk than non-diabetic patients for complications, a comprehensive review of the literature does not demonstrate substantial increased risk of intravitreal injections in patients with diabetes.

Comparison of the effects of intravitreal bevacizumab and triamcinolone acetonide in the treatment of macular edema secondary to central retinal vein occlusion

AIM

To compare the effects of intravitrealbevacizumab (IVB) and intravitreal triamcinolone acetonide (IVT) in the treatment of macular edema (ME) secondary to central retinal vein occlusion (CRVO).

MATERIALS AND METHODS

There were 20 patients treated with IVB (1.25 mg/0.05 mL) and 16 treated with IVT (4 mg/0.1 mL). The two groups were compared with regard to best-corrected visual acuity (BCVA), central macular thickness (CMT) on optical coherence tomography (OCT), slit-lamp biomicroscopy and fundus fluorescein angiography results, intraocular pressure (IOP), numbers of injections, and adverse events.

RESULTS

The mean follow-up times in the IVB and IVT groups were 17.45±8.1 months (range: 8-33 months) and 19.94±10.59 months (range: 6-40 months), respectively (P = 0.431). Visual acuity increased and CMT decreased significantly within both groups, but no differences were observed between the groups (P = 0.718). The percentages of patients with increased IOP and iatrogenic cataracts were significantly higher in the IVT group than in the IVB group.

CONCLUSIONS

Treatment with IVB and IVT both resulted in significant improvement in visual acuity and a decrease in CMT in patients with ME secondary to non-ischemic CRVO, with no difference between the two treatments. The incidence of adverse events, however, was significantly greater in the IVT group than in the IVB group. IVB may be preferred over IVT for the treatment of ME in patients with non-ischemic CRVO.

Role of adenosine receptors in resveratrol-induced intraocular pressure lowering in rats with steroid-induced ocular hypertension

BACKGROUND

Steroid-induced ocular hypertension is currently treated in the same way as primary open-angle glaucoma. However, the treatment is often suboptimal and is associated with adverse effects. We evaluated the oculohypotensive effects of topical trans-resveratrol in rats with steroid-induced ocular hypertension and involvement of adenosine receptors (AR) in intraocular pressure (IOP) lowering effect of trans-resveratrol.

METHODS

The oculohypotensive effect of unilateral single-drop application of various concentrations of trans-resveratrol was first studied in oculonormotensive rats. Concentration with maximum effect was similarly studied in rats with steroid-induced ocular hypertension. Involvement of AR was studied by observing the alterations of IOP in response to trans-resveratrol after pretreating animals with AR subtype-specific antagonists. Additionally, we used computational methods, including 3D modelling, 3D structure generation and protein-ligand interaction, to determine the AR-trans-resveratrol interaction.

RESULTS

All concentrations of trans-resveratrol produced significant IOP reduction in normotensive rat eyes. Maximum mean IOP reduction of 15.1% was achieved with trans-resveratrol 0.2%. In oculohypertensive rats, trans-resveratrol 0.2% produced peak IOP reduction of 25.2%. Pretreatment with A₁ antagonist abolished the oculohypotensive effect of trans-resveratrol. Pretreatment with A₃ and A₂A AR antagonists produced significant IOP reduction in both treated and control eyes, which was further augmented by trans-resveratrol application in treated eyes. Computational studies showed that trans-resveratrol has highest affinity for A₂B and A₁, followed by A2A and A₃ AR.

CONCLUSION

Topically applied trans-resveratrol reduces IOP in rats with steroid-induced ocular hypertension. Trans-resveratrol-induced oculohypotension involves its agonistic activity at the A₁ AR.

Intraocular pressure rise is predictive of vision improvement after intravitreal triamcinolone acetonide for diabetic macular oedema: a retrospective analysis of data from a randomised controlled trial

Background

Intravitreal triamcinolone acetonide (IVTA) is an effective treatment for recalcitrant diabetic macular oedema (DMO). It has been shown to improve vision with benefits persisting up to five years. The most common initial side effect of IVTA treatment is rise in intraocular pressure, occurring in approximately 50% of patients within the first 6 months of treatment. We evaluated whether there is a correlation between the development of intraocular pressure rise and improvement in vision.

Methods

Analysis of individual data from 33 eyes of 33 participants treated with IVTA for DMO from a prospective, randomised, double-masked, placebo controlled trial. The degree of intraocular pressure (IOP) rise was correlated with improvement in best-corrected visual acuity (BCVA) at 1 and 6 months.

Results

The proportion of eyes gaining 5 or more logMAR letters was higher in eyes with greater IOP rise (p = 0.044). Better absolute improvement in BCVA at 6 months (p = 0.045) was also found in eyes with greater IOP rise. Regression analyses revealed a correlation between IOP rise of 10 or more mmHg and absolute BCVA improvement at 6 months (odds ratio 1.22, 95% confidence interval 1.01-1.48, p = 0.039), but not at 1 month.

Conclusions

IOP rise and vision improvement appear to be correlated following IVTA for DMO, suggesting that the mechanisms that cause both may be linked.

Trial Registration

Clinical trials.gov NCT00167518, September 5, 2005.

Long-term trends in intraocular pressure after combined vitrectomy with sub-tenon injection of triamcinolone acetonide

PURPOSE

To evaluate the long-term effect of vitrectomy by itself and combined vitrectomy with sub-Tenon injection of triamcinolone acetonide (TA) on intraocular pressure (IOP).

METHODS

In a retrospective cohort study, the medical records of 56 eyes of 56 patients who underwent nonemergent vitrectomy and were followed up for at least 24 months were reviewed. Thirty-two eyes of 32 patients underwent combined vitrectomy with sub-Tenon injection of TA. Twenty-four eyes of 24 patients underwent vitrectomy only. Increased IOP of >4 mmHg from the baseline, change in IOP from the baseline, and preoperative and postoperative measured IOPs were recorded and compared between the two groups, and with fellow eyes.

RESULTS

Minimum follow-up period was 24 months. Except the IOP at postoperative 1 day, there were no significant differences between vitrectomized eyes and nonvitrectomized fellow eyes. There were also no differences between vitrectomized eyes and eyes that underwent combined vitrectomy with sub-Tenon injection of TA. And in the comparison of the vitrectomy-only eye group and the vitrectomy with sub-Tenon TA eye group, there was also no significant difference during the whole follow-up period.

CONCLUSION

Vitrectomy by itself or combined vitrectomy with sub-Tenon injection of TA does not seem to increase IOP in the long term.

Estimation of ocular volume from axial length

BACKGROUND/AIMS

To determine which biometric parameters provide optimum predictive power for ocular volume.

METHODS

Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions.

RESULTS

Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV.

CONCLUSION

Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR.

Steroid differentiation: the safety profile of various steroids on retinal cells in vitro and their implications for clinical use (an American Ophthalmological Society thesis)

PURPOSE

To determine if potentially viable alternatives to the clinical use of intravitreal triamcinolone acetonide should be considered based on a comparative assessment of the in vitro effects of five commercially available corticosteroids. We hypothesized that dexamethasone, betamethasone, methylprednisolone, loteprednol etabonate, and fluocinolone acetonide, at clinically relevant doses, may show different levels of in vitro cytotoxicity to retinal cells.

METHODS

Cultures of human retinal pigment epithelial cells (ARPE-19) and rat embryonal neurosensory precursor retinal cells (R28) were treated with dexamethasone, betamethasone, methylprednisolone, loteprednol, or fluocinolone acetonide. Cell viability as a measure of cell death was determined by trypan blue dye exclusion assay. The mechanical effect of drug crystals was evaluated by solubilizing the steroid formulations. Mitochondrial dehydrogenase and membrane potential were assessed to measure cell damage.

RESULTS

Betamethasone, loteprednol, and methylprednisolone, in commercially available forms, caused significant cytotoxic changes to retinal cells in vitro at clinically relevant doses. This effect was less pronounced with solubilized betamethasone. Dexamethasone at concentrations up to 5 times the clinical dose of free drug injections and 1000 times greater than a drug implant did not cause decreased cell viability. Fluocinolone acetonide at doses 1000 times higher than observed with drug delivery systems showed no cytotoxic effect.

CONCLUSIONS

Betamethasone, loteprednol, and methylprednisolone exhibited cytotoxicity at clinically relevant doses and do not appear to be good therapeutic options for intravitreal use. In comparison, dexamethasone and fluocinolone acetonide, which exhibited fewer cytotoxic effects than other steroids, may be potentially viable alternatives to triamcinolone acetonide for clinical use.

Effects of triamcinolone acetonide on human trabecular meshwork cells in vitro

Aim:

To study the effects of triamcinolone acetonide (TA) on cultured human trabecular meshwork (HTM) cells.

Materials and Methods:

HTM cells were cultured and treated with 125, 250, 500 and 1000 μg/mL concentration of TA for 24 h. The cells were treated with both crystalline TA (TA-C) (commercial preparation) and solubilized TA (TA-S). Cell viability was measured by a trypan blue dye exclusion test. The activity of caspse-3/7 was measured by a fluorescence caspase kit and DNA laddering was evaluated by electrophoresis on 3% agarose gel. Levels of lactate dehydrogenase (LDH) were assessed with LDH cytotoxicity assay kit-II.

Results:

Mean cell viabilities of HTM cells after 24 h exposure to TA-C 125, 250, 500, and 1000 μg/mL were 75.4 ±2.45% (P < 0.0001), 49.43 ± 1.85% (P < 0.0001), 17.07 ± 2.39% (P < 0.0001), and 3.7 ± 0.9% (P < 0.0001), respectively, compared with the untreated HTM cells 92.49 ± 1.21%. The mean cell viabilities with 125, 250, 500, and 1000 μg/mL of TA-S were 94.47 ± 1.60% (P > 0.05), 90.13 ± 0.40% (P < 0.01), 85.57 ± 0.47% (P < 0.001), and 71.67 ± 3.30% (P < 0.0001), respectively, compared to DMSO-equivalent cultures. Untreated HTM control had a cell viability of 96.57 ± 1.98%. DMSO-treated controls of 125, 250, 500, and 1000 μg/mL had a cell viability of 94.73 ± 0.57%, 96.97 ± 1.08%, 93.97 ± 1.85%, and 97.27 ± 1.15%, respectively. There was no increase of caspase-3/7 activity in cultures treated with either TA-C or TA-S. DNA laddering showed no bands in the TA-C or TA-S treated cultures. There were significantly higher LDH release rates at all concentrations of TA-C compared to TA-S.

Conclusions:

Results show that the effect of TA-C and TA-S on HTM cells is due to cell death by necrosis at all concentrations except 125 μg/mL of TA-S. Elevated levels of LDH confirmed necrotic cell death. Our study also infers the relative safety of TA-S over TA-C.

Treatment of diabetic macular edema with sustained-release glucocorticoids: intravitreal triamcinolone acetonide, dexamethasone implant, and fluocinolone acetonide implant

INTRODUCTION

Diabetic macular edema (DME) can be treated with intravitreal glucocorticoids, particularly triamcinolone acetonide, dexamethasone (DEX), and fluocinolone acetonide (FA).

AREAS COVERED

The pathophysiology of DME includes multiple growth factors such as VEGF and also inflammatory mediators. Glucocorticoids act on DME through multiple pathways, and current research into their efficacy, safety, and therapeutic potential when administered intravitreally is discussed.

CONCLUSION

The intravitreal route of administration minimizes systemic side effects of glucocorticoids. Furthermore, sustained-release low-dose delivery via the DEX implant or the FA implant will limit frequent intravitreal injection and possibly some cost associated with intravitreal anti-VEGF therapy. In addition, the durable action of these treatments facilitates combination therapy. Patients can receive these implants as foundational therapy, and then receive additional treatment with laser or intravitreal anti-VEGF agents as combination therapy, which may conceivably provide some synergistic benefit. While the FA implant lasts much longer than the DEX implant, potentially decreasing the visit and treatment burden on patients and their families, the FA implant appears to have a greater risk of inducing ocular hypertension and cataract. However, these modalities have not been directly compared in a clinical trial and there is insufficient evidence to draw more elaborate conclusions.