Cystoid macular edema associated with topical latanoprost in glaucomatous eyes with a normally functioning blood-ocular barrier

Incidence of Acute Cystoid Macular Edema After Starting a Prostaglandin Analog Compared With Other Classes of Glaucoma Medications

PURPOSE

There is a longstanding belief that prostaglandin analogs (PGAs) may predispose patients with glaucoma to develop acute cystoid macular edema (CME). However, there is little solid evidence supporting this notion. The purpose of this study is to compare CME incidence rates among patients initiating treatment with different glaucoma medication classes.

DESIGN

Database study.

PARTICIPANTS

39948 patients who were newly prescribed glaucoma medications METHODS: Using data from 10 health systems contributing data to the Sight Outcomes Research Collaborative (SOURCE) Ophthalmology Data Repository, we identified all adults with glaucoma who had been newly started on a topical glaucoma medication. Patients with pre-existing documentation of macular edema were excluded. We assessed the incidence of CME among patients with glaucoma who were newly started on PGAs, topical beta blockers (BBs), alpha agonists (AAs), and carbonic anhydrase inhibitors (CAIs). Using multivariable logistic regression, and adjusting for sociodemographic factors, we assessed the odds of developing CME among patients prescribed each of the 4 glaucoma medication classes. We also performed a subset regression analysis including lens status as a co-variate.

MAIN OUTCOME MEASURES

Incidence of CME within 3 months of initiating therapy with different topical glaucoma medications.

RESULTS

Among the 39,948 patients were newly treated with a topical glaucoma medication, 139 (0.35%) developed CME. The incidence of CME was 0.13%, 0.65%, 0.55%, 1.76% for users of PGAs, BBs, alpha agonists (AAs) and carbonic anhydrase inhibitors (CAIs), respectively. After adjusting for sociodemographic factors, users of topical BBs, AAs and CAIs had substantially higher odds of developing CME compared with PGA users (P<0.001 for all comparisons). The subset analysis also showed higher odds ratio of the non-PGA medication classes in association with CME.

CONCLUSIONS

Clinicians should reconsider the notion that PGAs carry a higher risk of CME versus other glaucoma medication classes. If additional studies support the findings of these analyses, clinicians may feel more comfortable prescribing PGAs to patients with glaucoma without fear they will predispose patients to CME.

The Impact of Systemic Medications on Retinal Function

This study will provide a thorough review of systemic (and select intravitreal) medications, along with illicit drugs that are capable of causing various patterns of retinal toxicity. The diagnosis is established by taking a thorough medication and drug history, and then by pattern recognition of the clinical retinal changes and multimodal imaging features. Examples of all of these types of toxicity will be thoroughly reviewed, including agents that cause retinal pigment epithelial disruption (hydroxychloroquine, thioridazine, pentosan polysulfate sodium, dideoxyinosine), retinal vascular occlusion (quinine, oral contraceptives), cystoid macular edema/retinal edema (nicotinic acid, sulfa-containing medications, taxels, glitazones), crystalline deposition (tamoxifen, canthaxanthin, methoxyflurane), uveitis, miscellaneous, and subjective visual symptoms (digoxin, sildenafil). The impact of newer chemotherapeutics and immunotherapeutics (tyrosine kinase inhibitor, mitogen-activated protein kinase kinase, checkpoint, anaplastic lymphoma kinase, extracellular signal-regulated kinase inhibitors, and others), will also be thoroughly reviewed. The mechanism of action will be explored in detail when known. When applicable, preventive measures will be discussed, and treatment will be reviewed. Illicit drugs (cannabinoids, cocaine, heroin, methamphetamine, alkyl nitrite), will also be reviewed in terms of the potential impact on retinal function.

Twelve-month efficacy and safety of omidenepag isopropyl, a selective EP2 agonist, in open-angle glaucoma and ocular hypertension: the RENGE study

PURPOSE

To assess the long-term safety and efficacy of omidenepag isopropyl (OMDI) 0.002% (a first-in-class, selective, non-prostaglandin, prostanoid EP2 receptor agonist), alone or administered concomitantly with timolol 0.5%, in patients with open-angle glaucoma (OAG, including normal-tension and exfoliation glaucoma) or ocular hypertension (OHT).

STUDY DESIGN

Open-label, multicenter, Phase 3 study (NCT02822729).

METHODS

Patients aged ≥ 20 years, with OAG or OHT, and a baseline diurnal intraocular pressure (IOP) ≥ 16- < 22 mmHg (Group 1) or ≥ 22- ≤ 34 mmHg (Groups 2 and 3) were enrolled. All patients (N = 125) received OMDI 0.002% once daily. Group 3 also received timolol 0.5% twice daily. IOP was measured at baseline and at Weeks 2, 4, 8, 12, 26, 40, and 52.

RESULTS

Significant reductions in mean diurnal IOP from baseline occurred at every visit (P < 0.0001). Mean ± SE diurnal IOP reduction at Week 52 was -3.7 ± 0.3 mmHg (Group 1), -5.6 ± 0.5 mmHg (Group 2), and -8.4 ± 0.6 mmHg (Group 3). Most adverse events (AEs) were mild, and no serious treatment-related AEs were reported. Conjunctival hyperemia (incidence: monotherapy [Groups 1 and 2], 18.8%; concomitant [Group 3], 45.0%) and macular edema (ME)/cystoid macular edema (CME) (incidence: monotherapy, 11.8%; concomitant, 15.0%) occurred most frequently. All treatment-related ME/CME cases occurred in pseudophakic eyes and responded to standard-of-care treatment and study drug discontinuation.

CONCLUSIONS

In this study, OMDI 0.002%, alone or administered concomitantly with timolol 0.5%, resulted in sustained IOP reduction over 52 weeks in patients with OAG or OHT. Concomitant treatment resulted in increased efficacy and increased incidence of conjunctival hyperemia.

Development of nanoparticle-delivery systems for antiviral agents: A review

The COVID-19 pandemic has resulted in unprecedented increases in sickness, death, economic disruption, and social disturbances globally. However, the virus (SARS-CoV-2) that caused this pandemic is only one of many viruses threatening public health. Consequently, it is important to have effective means of preventing viral transmission and reducing its devastating effects on human and animal health. Although many antivirals are already available, their efficacy is often limited because of factors such as poor solubility, low permeability, poor bioavailability, un-targeted release, adverse side effects, and antiviral resistance. Many of these problems can be overcome using advanced antiviral delivery systems constructed using nanotechnology principles. These delivery systems consist of antivirals loaded into nanoparticles, which may be fabricated from either synthetic or natural materials. Nevertheless, there is increasing emphasis on the development of antiviral delivery systems from natural substances, such as lipids, phospholipids, surfactants, proteins, and polysaccharides, due to health and environmental issues. The composition, morphology, dimensions, and interfacial characteristics of nanoparticles can be manipulated to improve the handling, stability, and potency of antivirals. This article outlines the major classes of antivirals, summarizes the challenges currently limiting their efficacy, and highlights how nanoparticles can be used to overcome these challenges. Recent studies on the application of antiviral nanoparticle-based delivery systems are reviewed and future directions are described.

Glaucoma: Management and Future Perspectives for Nanotechnology-Based Treatment Modalities

Glaucoma, being asymptomatic for relatively late stage, is recognized as a worldwide cause of irreversible vision loss. The eye is an impervious organ that exhibits natural anatomical and physiological barriers which renders the design of an efficient ocular delivery system a formidable task and challenge scientists to find alternative formulation approaches. In the field of glaucoma treatment, smart delivery systems for targeting have aroused interest in the topical ocular delivery field owing to its potentiality to oppress many treatment challenges associated with many of glaucoma types. The current momentum of nano-pharmaceuticals, in the development of advanced drug delivery systems, hold promises for much improved therapies for glaucoma to reduce its impact on vision loss. In this review, a brief about glaucoma; its etiology, predisposing factors and different treatment modalities has been reviewed. The diverse ocular drug delivery systems currently available or under investigations have been presented. Additionally, future foreseeing of new drug delivery systems that may represent potential means for more efficient glaucoma management are overviewed. Finally, a gab-analysis for the required investigation to pave the road for commercialization of ocular novel-delivery systems based on the nano-technology are discussed.

Cystoid macular edema related to cataract surgery and topical prostaglandin analogs: Mechanism, diagnosis, and management

Cystoid macular edema (CME) is a form of macular retina thickening that is characterized by the appearance of cystic fluid-filled intraretinal spaces. It has classically been diagnosed upon investigation after a decrease in visual acuity; however, improvements in imaging technology make it possible to noninvasively detect CME even before a clinically significant decrease in central vision. Risk factors for the development of CME include diabetic retinopathy, retinal vein occlusion, uveitis, and cataract surgery. It has been proposed that eyes with elevated intraocular pressure after cataract surgery, including those treated with prostaglandin analog eye drops, may be at higher risk for the development of CME. We summarize the current knowledge of the molecular mechanisms underlying CME, the potential role of ocular surgery and topical glaucoma medication in increasing the risk of CME, the newly developed imaging methods for diagnosing CME, and the clinical management of CME.

Promising Approach in the Treatment of Glaucoma Using Nanotechnology and Nanomedicine-Based Systems

Glaucoma is considered a leading cause of blindness with the human eye being one of the body's most delicate organs. Ocular diseases encompass diverse diseases affecting the anterior and posterior ocular sections, respectively. The human eye's peculiar and exclusive anatomy and physiology continue to pose a significant obstacle to researchers and pharmacologists in the provision of efficient drug delivery. Though several traditional invasive and noninvasive eye therapies exist, including implants, eye drops, and injections, there are still significant complications that arise which may either be their low bioavailability or the grave ocular adverse effects experienced thereafter. On the other hand, new nanoscience technology and nanotechnology serve as a novel approach in ocular disease treatment. In order to interact specifically with ocular tissues and overcome ocular challenges, numerous active molecules have been modified to react with nanocarriers. In the general population of glaucoma patients, disease growth and advancement cannot be contained by decreasing intraocular pressure (IOP), hence a spiking in future research for novel drug delivery systems and target therapeutics. This review focuses on nanotechnology and its therapeutic and diagnostic prospects in ophthalmology, specifically glaucoma. Nanotechnology and nanomedicine history, the human eye anatomy, research frontiers in nanomedicine and nanotechnology, its imaging modal quality, diagnostic and surgical approach, and its possible application in glaucoma will all be further explored below. Particular focus will be on the efficiency and safety of this new therapy and its advances.

Association of Postoperative Topical Prostaglandin Analog or Beta-Blocker Use and Incidence of Pseudophakic Cystoid Macular Edema

PURPOSE

The purpose of this article is to determine the association of postoperative topical prostaglandin analog (PGA) or topical beta-blocker use and the incidence of pseudophakic cystoid macular edema (CME).

METHODS

This was a nested case-control study. All adult patients who underwent cataract surgery between January 1, 2006 and December 31, 2016 and who were enrolled in the PharMetrics Plus database were eligible for inclusion. The association between postoperative topical PGAs (bimatoprost, latanoprost, and travoprost/travoprost-z) or beta-blocker (betaxolol, levobunolol, and timolol) use and the incidence of pseudophakic CME was assessed by conditional logistic regression.

RESULTS

Five hundred eight cases and 5080 controls were included in the analyses. Incidence of pseudophakic CME was found to be statistically significantly associated with the current postoperative use of both topical PGAs [relative risk (RR), 1.86; 95% confidence interval (CI), 1.04-3.32] and topical beta-blockers (RR, 2.64; 95% CI, 1.08-6.49). Postoperative use of each of bimatoprost (RR, 2.73; 95% CI, 1.35%-5.53%) and travoprost/travoprost-z (RR, 3.16; 95% CI, 1.42-7.03) in the year before diagnosis was demonstrated to be statistically significantly associated with the incidence of pseudophakic CME. This association was not observed to be statistically significant with the postoperative use of latanoprost (RR, 1.55; 95% CI, 0.84-2.88).

CONCLUSIONS

To the best of our knowledge this is the largest study that has investigated the association between postoperative topical PGA or topical beta-blocker use and the incidence of pseudophakic CME. Postoperative use of both topical PGAs and topical beta-blockers was found to be associated with the incidence of pseudophakic CME.

Pseudophakic Macular Edema in Primary Open-Angle Glaucoma: A Prospective Study Using Spectral-Domain Optical Coherence Tomography

PURPOSE

To determine the incidence of and risk factors for pseudophakic macular edema (PME) after uncomplicated cataract surgery in primary open-angle glaucoma (POAG) using spectral-domain optical coherence tomography (SDOCT).

DESIGN

Cohort study.

METHODS

Macular retinal thickness was evaluated using SDOCT at 1 week before surgery and at 1, 3, 6, and 12 months postoperatively, in 70 POAG and 68 control eyes. Forty-three healthy subjects without impaired vision or cystoid PME were recruited separately as pilot samples to define significant PME. Significant PME was defined as an increase in the average thickness exceeding the mean + 3 standard deviations of the increase shown in the pilot samples.

RESULTS

Significant PME (increase in the foveal 3-mm zone thickness of >19.5 μm) was observed in 31 (44%) eyes with POAG and in 14 (21%) control eyes (P = .003). The extent of PME was maximal at 3 months postoperatively and decreased gradually until 12 months. Regression tree analysis revealed that the risk of PME was the greatest in the POAG group using prostaglandin analogue (PGA) (odds ratio [OR] = 5.51), followed by POAG not using PGA (OR = 1.70), and control group (OR = 1.0). Risk factors for PME were younger age in all groups (OR = 1.07), systemic hypertension in PGA users (OR = 6.42), higher untreated IOP in PGA nonusers (OR = 1.09) and male sex (OR = 14.06) and diabetes mellitus (OR = 16.71) in the control group.

CONCLUSIONS

The incidence of PME as observed by SDOCT was higher than previously reported after uncomplicated cataract surgery. Eyes with POAG were at greater risk for PME, which was mainly associated with perioperative PGA use.

Nanotechnology-based strategies for treatment of ocular disease

Ocular diseases include various anterior and posterior segment diseases. Due to the unique anatomy and physiology of the eye, efficient ocular drug delivery is a great challenge to researchers and pharmacologists. Although there are conventional noninvasive and invasive treatments, such as eye drops, injections and implants, the current treatments either suffer from low bioavailability or severe adverse ocular effects. Alternatively, the emerging nanoscience and nanotechnology are playing an important role in the development of novel strategies for ocular disease therapy. Various active molecules have been designed to associate with nanocarriers to overcome ocular barriers and intimately interact with specific ocular tissues. In this review, we highlight the recent attempts of nanotechnology-based systems for imaging and treating ocular diseases, such as corneal d iseases, glaucoma, retina diseases, and choroid diseases. Although additional work remains, the progress described herein may pave the way to new, highly effective and important ocular nanomedicines.

Assessment of the Anterior Chamber Flare and Macular Thickness in Patients Treated with Topical Antiglaucomatous Drugs

PURPOSE

To determine the changes in the anterior chamber flare and central macular thickness (CMT) under topical antiglaucomatous therapy.

METHODS

This study included 121 eyes of 73 patients and 36 eyes of 18 controls. Glaucoma patients were divided into 3 groups (timolol maleate, latanoprost, and bimatoprost). Control eyes did not receive any medications. Flare and CMT measurements were performed at baseline and follow-up visits (15th day, and 1st, 3rd, 6th, and 12th month).

RESULTS

Statistically significant increases were detected in the flare values in the bimatoprost and latanoprost groups (P < 0.001, P = 0.011, respectively). Significant increases were also found in CMT values measured in these 2 groups (P < 0.001, P = 0.002, respectively). However, increased flare and CMT values were not clinically manifested as uveitis and macular edema. Flare and CMT values did not change statistically in the timolol maleate and control groups.

CONCLUSIONS

Although the use of prostaglandin (PG) analogs was found to be associated with increased flare and CMT, these increases were not clinically significant. PG analog monotherapy may be safely and effectively used in the treatment of glaucoma.

Acute macular edema following intracorporeal prostaglandin injection for erectile dysfunction

PURPOSE

We aimed to describe the first case of macular edema following intracorporeal injection of alprostadil, a prostaglandin E1.

METHODS

This was a retrospective case report followed with optical coherence tomography, fundus photos, and fluorescein angiography images.

RESULTS

A patient developed bilateral cystoid macular edema following intracorporeal injection of alprostadil, a prostaglandin E1 for treatment of erectile dysfunction. The edema resolved following treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids, with subsequent recovery in visual acuity.

DISCUSSION

Systemic prostaglandin administration can cause macular edema and vision loss, indicating that elevated systemic prostaglandin levels may affect visual function. This has potential implications for other systemic disorders and treatments that could affect macular function.

Perioperative pharmacological management in patients with glaucoma

REVIEẂS AIM: When a phacoemulsification, a filtration surgery or a combined surgery are necessary, questions about the convenience of continuing certain antiglaucomatous drugs could appear. The aim of this review article is to unify criteria that will guide daily clinical practice and including the developing algorithms of action in the preoperative and postoperative periods of filtration surgery and/or cataract surgery.

PROPOSED PROTOCOLS

In the preoperative period of cataract surgery, the use of non-steroidal anti-inflammatory drugs is at the discretion of the surgeon, with the monodose presentation being recommended. The suspension of prostaglandines a fewdays before the surgery should be considered. Preservative-free drugs ensure a better recovery of the ocular surface (OS) after cataract surgery. Once all modifying factors of the intraocular pressure (IOP) have been removed, baseline IOP should be evaluated again, choosing preservative-free antiglaucomatous drugs when needed. The use of preservative-free ocular antihypertensive drugs and steroids in the preoperative period of glaucoma surgery reduces the risk of surgical failure. The interruption of prostaglandines is recommended. In the postoperative period of glaucoma surgery, steroids are the anti-inflammatory treatment of choice, the preservative-free ones being preferred. When reintroducing antiglaucomatous treatment, preservatives should be avoided to prevent scarring. The appropriate perioperative management of patients with glaucoma is essential to obtain a correct control of IOP, improve the situation of the OS, prevent complications and improve the result of the filtration surgery and cataract surgery.

CONCLUSIONS

this protocol aims to unify the different lines of action in order to decrease the incidence of adverse events and maximize the surgical outcome.

Subtenon triamcinolone injection for postoperative cystoid macular edema associated with tafluprost

PURPOSE

We report the successful treatment of a case of cystoid macular edema (CME) associated with topical tafluprost, which was accompanied by serous retinal detachment (SRD).

CASE

A 78-year-old woman underwent intraocular lens suture surgery, including anterior vitreous cutting, for crystalline lens dislocation in the right eye. Tafluprost was initiated 12 weeks after surgery. Intraocular pressure (IOP) was controlled at 10-14 mmHg. Visual acuity remained at 20/40-30/40. However, the patient complained of blurred vision (20/200) 9 months after surgery. CME accompanied by SRD was identified by optical coherence tomography (OCT) and treated with subtenon triamcinolone injection. Visual acuity rapidly increased to 20/50, and the volume of SRD decreased in a few days. Discontinuation of tafluprost and initiation of diclofenac eye drops improved visual acuity to 20/40 and resulted in improved OCT findings within a few weeks. Three months after injection, tafluprost was resumed along with diclofenac. No recurrence of CME occurred over the following 3 months, and IOP was controlled at 10-15 mmHg.

CONCLUSION

SRD is considered to be a symptom of treatment-resistant CME, which may lead to poor visual acuity after recovery. In such cases, subtenon triamcinolone injection should be strongly considered at an early stage.

Therapeutic uses of prostaglandin F(2α) analogues in ocular disease and novel synthetic strategies

The pharmacological management of glaucoma and ocular hypertension has significantly changed over the last 18 years with the introduction of PGF2α analogues, more specifically latanoprost (6), travoprost (8), bimatoprost (10) and tafluprost (12). Prostanoids are currently the first-line medicines among ocular antihypertensive drugs in terms of efficacy, safety, patient compliance and medical economy. Their ability to effectively reduce intraocular pressure with once-per-day dosing, ocular tolerability comparable to timolol and general lack of systemic adverse effects have made them the mainstay of pharmacological therapy for glaucoma and ocular hypertension all over the world. The present review reports a novel, convergent and highly diastereoselective method for the synthesis of PGF2α analogues from the structurally advanced prostaglandin phenylsulfone (5Z)-(+)-15 and new ω-chain synthons. The biochemistry, clinical efficacy and side effects of four commercially available PGF2α analogues, currently used as first-line agents for reducing intraocular pressure in patients with glaucoma or ocular hypertension, are also discussed.

Successful treatment of prostaglandin-induced cystoid macular edema with subtenon triamcinolone

Purpose

Cystoid macular edema (CME) is associated with the use of prostaglandin eye drops after cataract surgery. The study aim was to report on the treatment of two CME patients with subtenon triamcinolone injections.

Methods

Case one was a 70-year-old woman who underwent uneventful cataract surgery. Travoprost was administrated at 10 weeks after surgery, and CME occurred at 13 weeks after surgery. Case two was an 85-year-old man who underwent intraocular lens extraction and an intraocular lens suture operation. Latanoprost was readministered after the surgery. The patient complained of blurred vision 3 years later.

Results

For both cases, discontinuation of the prostaglandin eye drops, subsequent initiation of treatment with diclofenac eye drops, and subtenon injection of triamcinolone was followed by the rapid disappearance of the CME. After the CME had disappeared for 3 months, the prostaglandin eye drops were resumed. Diclofenac was added in case two. No CME recurrence was seen in either case over 2 years.

Conclusion

Subtenon triamcinolone injection can be effective for CME associated with prostaglandin eye liquid after cataract surgery. Prostaglandin eye liquid that causes CME is not necessarily precluded for future use if administered under careful observation.

Prostaglandin-induced cystoid macular edema following routine cataract extraction

To our knowledge, we are reporting the first case of a 59-year-old man who developed recurrent CME with three separate trials of three different prostaglandin class drugs following uncomplicated phacoemulsification with intraocular lens implantation. Despite multiple reports of individual prostaglandin (PG) analogues being suggested as the cause of CME, there are no recommendations regarding withholding these medications in the perioperative period. Our patient first developed CME OD 4-months post uncomplicated cataract extraction. XALATAN (Latanoprost) had been restarted after surgery and discontinued at onset of CME. While off XALATAN (Latanoprost), the patient's CME resolved, but his IOP rose. The patient was started on LUMIGAN (Bimatoprost) to control the IOP, but within weeks his CME recurred. The patient's CME was again treated and his IOP remained acceptable, but then progressively increased. TRAVATAN (Travoprost) was attempted, but he presented with a third round of CME. Definitive conclusions about causal relationships cannot be made without well-designed, prospective clinical trials addressing this issue.

Clinical utility and differential effects of prostaglandin analogs in the management of raised intraocular pressure and ocular hypertension

Prostaglandin analogs (PGA) are powerful topical ocular hypotensive agents available for the treatment of elevated intraocular pressure (IOP). Latanoprost 0.005% and travoprost 0.004% are prodrugs and analogs of prostaglandin F2α. Bimatoprost 0.03% is regarded as a prostamide, and debate continues as to whether it is a prodrug. The free acids of all 3 PGAs reduce IOP by enhancing uveoscleral and trabecular outflow via direct effects on ciliary muscle relaxation and remodeling of extracellular matrix. The vast majority of clinical trials demonstrate IOP-lowering superiority of latanoprost, bimatoprost and travoprost compared with timolol 0.5%, brimonidine 0.2%, or dorzolamide 2% monotherapy. Bimatoprost appears to be more efficacious in IOP-lowering compared with latanoprost, with weighted mean difference in IOP reduction documented in one meta-analysis of 2.59% to 5.60% from 1- to 6-months study duration. PGAs reduce IOP further when used as adjunctive therapy. Fixed combinations of latanoprost, bimatoprost or travoprost formulated with timolol 0.5% and administered once daily are superior to monotherapy of its constituent parts. PGA have near absence of systemic side effects, although do have other commonly encountered ocular adverse effects. The adverse effects of PGA, and also those found more frequently with bimatoprost use include ocular hyperemia, eyelash growth, and peri-ocular pigmentary changes. Iris pigmentary change is unique to PGA treatment. Once daily administration and near absence of systemic side effects enhances tolerance and compliance. PGAs are often prescribed as first-line treatment for ocular hypertension and open-angle glaucoma.

Side effects associated with prostaglandin analog therapy

Topical prostaglandin analogs, which have become first-line therapy in the medical management of glaucoma, have an excellent safety profile with regard to systemic side effects, but are associated with several ocular side effects. Some of these are common, with no apparent serious consequences other than cosmetic, whereas others are much less common but represent potentially sight-threatening side effects. The former group includes conjunctival hyperemia, elongation and darkening of eyelashes, induced iris darkening, and periocular skin pigmentation. The latter group of side effects, which are relatively rare and lack definitive causal relationship to prostaglandin analog therapy, includes iris cysts, cystoid macular edema, anterior uveitis, and reactivation of herpes simplex keratitis. Most of the literature regarding side effects associated with prostaglandin analogs involves the use of latanoprost, probably because it was the first to be studied. There is no evidence, however, aside from less conjunctival hyperemia with latanoprost, that the commercially available prostaglandin analogs differ significantly with regard to side effects.

Influence of topical bimatoprost on macular thickness and volume in glaucoma patients with phakic eyes

BACKGROUND

In light of concern about the possible relation between the extensive clinical use of prostaglandin analogues and the development of retinal disorders such as cystoid macular edema, this study investigated the influence of topical application of bimatoprost 0.03% on macular thickness and volume in glaucoma patients with phakic eyes.

METHODS

A total of 40 eyes in 22 patients with primary open-angle glaucoma or normal-tension glaucoma were evaluated in this study. Optical coherence tomography images were taken before initiation of bimatoprost application and after 1, 2, and 3 months of treatment. In addition, best-corrected visual acuity (BCVA) and intraocular pressure (IOP) were measured, and contrast sensitivity tests and fundus examinations were performed. Changes in various parameters, including macular thickness and volume, were analyzed.

RESULTS

BCVA and contrast sensitivity did not change from baseline over the treatment period. IOP declined by 20% to 25% from baseline for 1 month before stabilizing. Macular thickness and volume did not increase significantly during the 3 months.

INTERPRETATION

Topical application of bimatoprost does not induce clinical or structural changes in the macula, at least in glaucoma patients with phakic eyes. Moreover, bimatoprost effectively lowered IOP without causing macular disorders such as cystoid macular edema.

The effects of prostaglandin analogues on the blood aqueous barrier and corneal thickness of phakic patients with primary open-angle glaucoma and ocular hypertension

PURPOSE

To evaluate the effects of topical latanoprost, travoprost, and bimatoprost on the blood-aqueous barrier and central corneal thickness (CCT) of patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT).

DESIGN

Prospective, randomized, masked-observer, crossover clinical trial.

METHODS

A total of 34 phakic patients with POAG or OHT with no previous history of intraocular surgery or uveitis completed the study. Patients were randomized to use latanoprost 0.005%, travoprost 0.004%, or bimatoprost 0.03% once daily (2000 hours) for 1 month, followed by a washout period of 4 weeks between each drug. Aqueous flare was measured with a laser flare metre. CCT was calculated as the average of five measurements using ultrasound pachymetry. All measurements were performed by a masked observer (1000 h).

RESULTS

There were no statistically significant differences between baseline mean IOP, mean CCT, and mean flare values among the groups. There was no statistically significant increase in mean flare values from baseline in all groups (P>0.05). There were no statistically significant differences between mean flare values among the groups (P>0.05). All medications significantly reduced the mean IOP from baseline (P<0.0001). IOP reduction obtained with travoprost (7.3+/-3.8 mmHg) was significantly higher than that obtained with latanoprost (4.7+/-4.2 mmHg) (P=0.01). A statistically significant reduction in mean CCT (0.6+/-1.3%) from baseline was observed when patients instilled bimatoprost (P=0.01).

CONCLUSIONS

Latanoprost, travoprost, and bimatoprost had no statistically significant effect on the blood-aqueous barrier of phakic patients with POAG or OHT. Bimatoprost may be associated with a clinically irrelevant reduction in mean CCT.

A 6-month assessment of bimatoprost 0.03% vs timolol maleate 0.5%: hypotensive efficacy, macular thickness and flare in ocular-hypertensive and glaucoma patients

AIM

To compare 6 months of treatment with bimatoprost and timolol in terms of their hypotensive efficacy and secondary effects, including changes in macular thickness and the inflammatory reaction induced in the anterior chamber.

METHODS

A prospective, randomized, parallel-group trial performed on 30 eyes of 30 patients per group. The main outcome measure was the difference between the IOP value taken between the baseline visit and the 6-month-visit. Macular thickness determined through optical coherence tomography and anterior chamber inflammation estimated using the laser flare meter was also evaluated. Adverse events were recorded during the study period.

RESULTS

Bimatoprost treatment gave rise to a significantly lower mean IOP than timolol in all follow-up visits as from the first month (P<0.05). Bimatoprost achieved high percentage IOP reductions from baseline in a significantly higher proportion of patients (P<0.05). Macular thickness and anterior chamber flare failed to vary significantly both between the two groups and within each group during the 6-month evaluation (P>0.05).

CONCLUSIONS

Bimatoprost 0.03% once daily showed a greater efficacy then timolol 0.05% twice daily in patients with elevated IOP. No significant differences were detected in macular thickness or anterior uveitis using optical coherence tomography and laser flare photometry.

Cystoid macular edema in a low-risk patient after switching from latanoprost to bimatoprost

PURPOSE

To report a case of angiographically documented cystoid macula edema occurring after switching a pseudophakic patient from latanoprost to bimatoprost.

DESIGN

Observational case report.

METHODS

A 68-year-old man developed intense conjunctival hyperemia and cystoid macula edema after switching from latanoprost to bimatoprost 9 months after cataract surgery in an eye at low-risk for this cystoid macular edema.

RESULTS

Bimatoprost was discontinued and diclofenac initiated. After 2 months, visual acuity and ocular hyperemia returned to baseline levels. Fundus examination revealed resolution of cystoid macula edema.

CONCLUSION

It is possible that pseudophakic eyes that develop intense conjunctival hyperemia associated with ocular hypotensive lipids might be at higher risk for developing cystoid macula edema.

Cystoid macular edema in aphakia and pseudophakia after use of prostaglandin analogs

Prostaglandin analogs are powerful ocular hypotensive agents that may also be associated with a breakdown of the blood-retinal barrier and cystoid macular edema. The association is evident in pseudophakic or aphakic patients. This paper presents a case of unilateral latanoprost-associated clinical cystoid macular edema in a bilaterally pseudophakic patient; the only difference between the two eyes was the presence of a capsulotomy in the affected eye. We review the literature concerning prostaglandin analog-associated cystoid macular edema, as well as the evidence for prostaglandin analog-associated breakdown of the blood-retinal barrier. Although some evidence is suggestive of a connection between prostaglandin analogs and cystoid macular edema, many questions concerning the complex physiology of prostanoids remain. Until our understanding of these issues is more advanced, judicious use of prostaglandin analogs in patients at risk for cystoid macular edema would be prudent.

Putative side effects of prostaglandin analogs

Anecdotal case reports describe the occurrence of cystoid macular edema, iritis, herpes simplex keratitis, periocular skin darkening, and headaches in patients treated with prostaglandin analogs for glaucoma. The purpose of this article is to critically analyze these anecdotal case reports in light of a few well-controlled, randomized clinical studies to determine whether conclusions can be made about a causal relationship between the use of prostaglandin analogs and the occurrence of these side effects. None of these putative side effects has been proven to be causally related to latanoprost therapy using valid scientific methodology. These possible side effects occur rarely. Cystoid macular edema, iritis, and herpes simplex keratitis occur in eyes with risk factors. To scientifically establish a causal relationship between drug therapy and rare side effects, repeated rechallenging with masked controls is required. With rare exception, such methodology has not been used with any of these putative side effects. Nevertheless, even without firm establishment of a causal relationship, caution is advised with the use of prostaglandin analogs in eyes with risk factors for cystoid macular edema, iritis, and herpes simplex keratitis until properly designed, large, controlled studies provide more definitive information.