A Case of Sterile Corneal Stromal Infiltration with Hypotonic Maculopathy Under Brimonidine Treatment.

INTRODUCTION: Brimonidine is a commonly used drug for glaucoma treatment, which has been linked to ocular autoimmune disorders like uveitis and conjunctivitis. Corneal pathology under brimonidine is generally less common. CASE DESCRIPTION: Here, we report a 78 -year-old male patient suffering from immune corneal stromal inflammation with hypotony and resulting hypotonic maculopathy after 6 weeks after introduction of brimonidine treatment. Systemic work-up for system autoimmune and infectious diseases was negative. We discontinued brimonidine and administered topical prednisolone under which inflammatory corneal signs and intraocular pressure normalized. Chorioretinal folds persisted after 9 months. CONCLUSION: Our case report suggests monitoring patients under brimonidine for sterile corneal infiltration.

Efficacy and safety of topical brimonidine in dermatology: A review article.

Brimonidine is a vasoconstrictive agent used to treat several dermatologic disorders. Here, we review the uses of brimonidine in different aspects of dermatology. We searched keywords including rosacea, erythema, topical brimonidine, dermatology, and skin disease in PubMed, Cochrane, and Google Scholar to collect the related published articles. In a review of 15 articles, we found topical brimonidine improved the facial erythema of rosacea. In addition, it reduced the erythema associated with alcohol flushing syndrome, intense pulsed light therapy, and photodynamic therapy. Furthermore, topical brimonidine was used as a hemostatic agent in dermatosurgery procedures such as Mohs surgery and nail surgery to reduce intra-operative and postoperative bleeding. Some side effects such as erythema, flushing, and burning were reported in a few patients. Based on our findings, brimonidine is a beneficial drug that can be used in various dermatologic disorders with negligible side effects.

Local vasoregulative interventions impact drug concentrations in the skin after topical laser-assisted delivery.

INTRODUCTION: The ability of ablative fractional lasers (AFL) to enhance topical drug uptake is well established. After AFL delivery, however, drug clearance by local vasculature is poorly understood. Modifications in vascular clearance may enhance AFL-assisted drug concentrations and prolong drug dwell time in the skin. Aiming to assess the role and modifiability of vascular clearance after AFL-assisted delivery, this study examined the impact of vasoregulative interventions on AFL-assisted 5-fluorouracil (5-FU) concentrations in in vivo skin. METHODS: 5-FU uptake was assessed in intact and AFL-exposed skin in a live pig model. After fractional CO2 laser exposure (15 mJ/microbeam, 5% density), vasoregulative intervention using topical brimonidine cream, epinephrine solution, or pulsed dye laser (PDL) was performed in designated treatment areas, followed by a single 5% 5-FU cream application. At 0, 1, 4, 48, and 72 h, 5-FU concentrations were measured in 500 and 1500 µm skin layers by mass spectrometry (n = 6). A supplemental assessment of blood flow following AFL ± vasoregulation was performed using optical coherence tomography (OCT) in a human volunteer. RESULTS: Compared to intact skin, AFL facilitated a prompt peak in 5-FU delivery that remained elevated up to 4 hours (1500 µm: 1.5 vs. 31.8 ng/ml [1 hour, p = 0.002]; 5.3 vs. 14.5 ng/ml [4 hours, p = 0.039]). However, AFL's impact was transient, with 5-FU concentrations comparable to intact skin at later time points. Overall, vasoregulative intervention with brimonidine or PDL led to significantly higher peak 5-FU concentrations, prolonging the drug's dwell time in the skin versus AFL delivery alone. As such, brimonidine and PDL led to twofold higher 5-FU concentrations than AFL alone in both skin layers by 1 hour (e.g., 500 µm: 107 ng/ml [brimonidine]; 96.9 ng/ml [PDL], 46.6 ng/ml [AFL alone], p ≤ 0.024), and remained significantly elevated at 4 hours (p ≤ 0.024). A similar pattern was observed for epinephrine, although trends remained nonsignificant (p ≥ 0.09). Prolonged 5-FU delivery was provided by PDL, resulting in sustained drug deposition compared to AFL alone at both 48 and 72 hours in the superficial skin layer (p ≤ 0.024). Supporting drug delivery findings, OCT revealed that increases in local blood flow after AFL were mitigated in test areas also exposed to PDL, brimonidine, or epinephrine, with PDL providing the greatest, sustained reduction in flow over 48 hours. CONCLUSION: Vasoregulative intervention in conjunction with AFL-assisted delivery enhances and prolongs 5-FU deposition in in vivo skin.

Treatment of rosacea during pregnancy.

BACKGROUND: Exacerbation of rosacea may occur during pregnancy and there are multiple associated cases of rosacea fulminans (RF). Treatment during pregnancy poses a significant challenge as many rosacea treatments are contraindicated or have limited evidence regarding potential adverse fetal effects. OBJECTIVE: Review the pregnancy categories of various treatments and develop algorithms for treating pregnant patients with rosacea and RF. METHODS: Rosacea treatments showing efficacy in randomized controlled trials were searched through DailyMed to review pregnancy labelling. Searching the PubMed/MEDLINE database for English articles using keywords "rosacea fulminans AND pregnancy" without publishing-time restrictions yielded 8 articles. We summarized treatments used in cases of RF during pregnancy. RESULTS: Topical ivermectin was more effective than metronidazole, but has a more concerning pregnancy category. Three pregnant women with RF were treated successfully with topical metronidazole in combination with other therapies. Azithromycin is the only oral rosacea therapy that is considered safe for pregnant patients and it has been used to treat RF. CONCLUSIONS: This review highlights the challenging aspects of treating pregnant patients with rosacea, as there is limited pregnancy-related treatment efficacy and safety data. The pregnancy categories of therapeutic options are summarized. Further studies are needed to learn which therapies are effective and safe for use during pregnancy.

Rosacea: An Update in Diagnosis, Classification and Management.

The diagnosis and classification of rosacea has been modified to reflect presenting features. On exclusion of differentials, the diagnosis of rosacea is based on the presence of either (1) phymatous changes, or (2) centrofacial persistent erythema. In their absence, diagnosis can be established by presence of any two of: flushing/transient erythema, papules and pustules, telangiectases, or ocular manifestations. Management of rosacea depends on presenting feature(s), their severity, and impact. General management includes gentle skin care, sun protection, and trigger avoidance. Evidence-based treatment recommendations include topical brimonidine and oxymetazoline for persistent erythema; topical azelaic acid, ivermectin, metronidazole, minocycline and oral doxycycline, tetracycline and isotretinoin for papules and pustules; vascular lasers and light devices for telangiectases; and omega-3 fatty acids and cyclosporine ophthalmic emulsion for ocular rosacea. While surgical or laser therapy can be considered for clinically noninflamed phyma, there are no trials on their utility. Combination therapies include topical brimonidine with topical ivermectin, or topical metronidazole with oral doxycycline. Topical metronidazole, topical ivermectin, and topical azelaic acid are appropriate for maintenance therapy. In conclusion, the updated phenotype approach, based on presenting clinical features, is the foundation for current diagnosis, classification, and treatment of rosacea.

Erythematotelangiectatic rosacea: The combination of 0.5% brimonidine tartrate gel and broadband pulse light therapy to reverse its effects.

Rosacea is a common skin disease that is troublesome for both the patients and the dermatologists. Erythema, telangiectasia, papulopustular changes, and phymatous changes are the main problems faced by the patients and dermatologists in everyday practice. Due to the chronic and relapsing nature of the disease, patients are usually unsatisfied with conventional treatment methods. We report a case of a patient with rosacea, erythematotelangiectatic subtype with an eight-year history of progressive worsening and experience of combined therapy based on the broadband pulse light and topical 0.5% brimonidine tartrate gel. The effectiveness of the therapy was evaluated using multispectral skin imaging that enables to define morphological patterns of the pathological skin areas in a real-time mode as well as to create the map of hemoglobin distribution and to measure its concentration in the rosacea foci. In this case report, an efficacy and very good tolerability of the abovementioned treatment have been demonstrated.

A case of latanoprost-induced diffuse facial skin hyperpigmentation.

INTRODUCTION: Latanoprost is a prostaglandin F2α analogue, which has been used as a first-line drug for open-angle glaucoma. Common side effects of latanoprost include hyperpigmentation. While it usually occurs on irides or periocular skin, diffuse facial hyperpigmentation is rarely reported. CASE PRESENTATION: A 71-year-old woman was presented with diffuse gray-brown colored maculopatches on her face. The symptom appeared 1 week after she started to use latanoprost eye drops for glaucoma. Biopsy specimen revealed vacuolar degeneration of dermo-epidermal junction and pigment incontinence in dermis. OBJECTIVE: The aim of this paper is to introduce a rare adverse effect of latanoprost and effective way of treatment. METHODS: We stopped her from using latanoprost. She was also treated with 532-nm potassium titanyl phosphate laser and low-fluence 1064-nm Q-switched Nd:YAG laser, while using topical agents. RESULT: After 10 weeks, we observed hyperpigmentation of her face was effectively and safely treated. The patient was satisfied with the result. CONCLUSION: Diffuse facial pigmentation could be one of the latanoprost-induced adverse effects and the laser treatments with topical agents we used can make it improve faster.

Interventions for rosacea based on the phenotype approach: an updated systematic review including GRADE assessments.

BACKGROUND: Rosacea is a common chronic facial dermatosis. Classification of rosacea has evolved from subtyping to phenotyping. OBJECTIVES: To update our systematic review on interventions for rosacea. METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index and ongoing trials registers (March 2018) for randomized controlled trials. Study selection, data extraction, risk-of-bias assessment and analyses were carried out independently by two authors. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to assess certainty of evidence. RESULTS: We included 152 studies (46 were new), comprising 20 944 participants. Topical interventions included brimonidine, oxymetazoline, metronidazole, azelaic acid, ivermectin and other topical treatments. Systemic interventions included oral antibiotics, combinations with topical treatments or other systemic treatments. Several studies evaluated laser or light-based treatment. We present the most current evidence for rosacea management based on a phenotype-led approach. CONCLUSIONS: For reducing temporarily persistent erythema there was high-certainty evidence for topical brimonidine and moderate certainty for topical oxymetazoline; for erythema and mainly telangiectasia there was low-to-moderate-certainty evidence for laser and intense pulsed light therapy. For reducing papules/pustules there was high-certainty evidence for topical azelaic acid and topical ivermectin; moderate-to-high-certainty evidence for doxycycline 40 mg modified release (MR) and isotretinoin; and moderate-certainty evidence for topical metronidazole, and topical minocycline and oral minocycline being equally effective as doxycycline 40 mg MR. There was low-certainty evidence for tetracycline and low-dose minocycline. For ocular rosacea, there was moderate-certainty evidence that oral omega-3 fatty acids were effective and low-certainty evidence for ciclosporin ophthalmic emulsion and doxycycline.

Topical brimonidine-assisted laser treatment for the prevention of therapy-related erythema and hyperpigmentation.

Postinflammatory hyperpigmentation (PIH) and erythema are the most common adverse effects associated with laser treatment, particularly in dark-skinned individuals. Several methods have been used to prevent or minimize these adverse effects; however, to date, no definitive precautions/strategies are known to prevent post-laser PIH and erythema. We investigated whether the topical application of the α-adrenergic receptor agonist brimonidine could reduce laser treatment-related complications such as erythema and PIH.

Impact of Ocular Compatible Lipoids and Castor Oil in Fabrication of Brimonidine Tartrate Nanoemulsions by 33 Full Factorial Design.

BACKGROUND: Brimonidine Tartrate (BRT) is used in the treatment of glaucoma. Brimonidine tartrate nanoemulsion was fabricated in this research work to enhance the permeability through barriers and faster onset of action and therapeutic effect. OBJECTIVE: To fabricate an ocular compatible nanoemulsion of brimonidine tartrate by using surfactant and co-surfactants. METHODS: The experimental work involved compatibility studies by using FTIR, DSC and crystallinity study by XRD. The prepared nanoemulsion was studied by photon correlation spectroscopy by Malvern S90 for the particle size analysis and characterized for Z average value (d.nm.) and PDI. Further studies were conducted by laser light scattering technique by delsanano common and TEM. RESULTS: The study demonstrated that the formulations BN2, BN3, BN10 demonstrated the z average value of 19.48, 22.14,26.50 d.nm. With 0.337, 0.270, 0.289 PDI respectively, the formulae BN2, BN3, BN10 demonstrated the distribution average diameter (nm) of 376.8 + 258.4, 542.8 + 494.4, 398.8 + 263.9 with the diameter of 267.5, 298.5, 272.7, respectively. The zeta potential of BN10 was -21.26 mV and other parameters such as TEM and drug release studies were also reported. CONCLUSION: The nanoemulsion of brimonidine tartrate was prepared successfully by using castor oil, Lipoid S75 (Fat free soybean phospholipids with 70% phosphatidylcholine), Lipoid E80 (Egg phospholipids with 80% phosphatidylcholine) and PF- 68. The optimised formula demonstrated the lower droplet size, satisfactory zeta potential, and high drug loading and reproducible drug release profile. Brimonididne taratarate is reported in various recent patents for various applications and is the potential candidate for future therapy. Nanoemulsion is widely explored as potential alternatives for conventional ophthalmic formulation based approaches. It enhances the ocular bioavailability by reducing the drug protein binding, increasing the corneal resident time, enhancing the drug permeability and providing a sustained drug release.It reported a significant increase in therapeutic efficacy for various chronic ocular disease states of both the anterior and posterior ocular segments.

Nanostructured lipid carriers for intraocular brimonidine localisation: development, in-vitro and in-vivo evaluation.

Brimonidine ocular hypotensive effect can be enhanced by increasing residence time and corneal penetration. The current work aimed to formulate, evaluate and compare nanostructured lipid carriers (NLCs) to solid lipid nanoparticles (SLNs) and commercial eye drops for controlled brimonidine delivery. NLCs prepared by modified high shear homogenisation were spherical with a mean size of 151.97 ± 1.98 nm, negative zeta potential (ZP) of -44.2 ± 7.81 mV, % entrapment efficiency (EE) of 83.631 ± 0.495% and low crystallinity index (CI) (17.12%), indicating a better drug incorporation. Moreover, they kept stable during storage at 4 °C for 3 months. Permeability coefficient of NLCs was 1.227 folds higher than that of SLNs. Histological examination revealed localisation of NLCs in the anterior ocular chamber. NLCs revealed the most sustained and highest intraocular pressure (IOP) lowering activity (-13.14 ± 1.28 mmHg) in rabbits. In conclusion, NLCs is a promising approach for IOP reduction compared to eye drops and SLNs.

Interventions for rosacea.

BACKGROUND: Rosacea is a common chronic skin condition affecting the face, characterised by flushing, redness, pimples, pustules and dilated blood vessels. The eyes are often involved and thickening of the skin with enlargement (phymas), especially of the nose, can occur in some people. A range of treatment options are available but it is unclear which are most effective. OBJECTIVES: To assess the efficacy and safety of treatments for rosacea. SEARCH METHODS: We updated our searches, to July 2014, of: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2014, Issue 6), MEDLINE (from 1946), EMBASE (from 1974) and Science Citation Index (from 1988). We searched five trials registers and checked reference lists for further relevant studies. SELECTION CRITERIA: Randomised controlled trials in people with moderate to severe rosacea. DATA COLLECTION AND ANALYSIS: Study selection, data extraction, risk of bias assessment and analyses were carried out independently by two authors. MAIN RESULTS: We included 106 studies, comprising 13,631 participants. Sample sizes of 30-100 and study duration of two to three months were most common. More women than men were included, mean age of 48.6 years, and the majority had papulopustular rosacea, followed by erythematotelangiectatic rosacea.A wide range of comparisons (67) were evaluated. Topical interventions: metronidazole, azelaic acid, ivermectin, brimonidine or other topical treatments. Systemic interventions: oral antibiotics, combinations with topical treatments or other systemic treatments, i.e. isotretinoin. Several studies evaluated laser or light-based treatment.The majority of studies (57/106) were assessed as 'unclear risk of bias', 37 'high risk ' and 12 'low risk'. Twenty-two studies provided no usable or retrievable data i.e. none of our outcomes were addressed, no separate data reported for rosacea or limited data in abstracts.Eleven studies assessed our primary outcome 'change in quality of life', 52 studies participant-assessed changes in rosacea severity and almost all studies addressed adverse events, although often only limited data were provided. In most comparisons there were no statistically significant differences in number of adverse events, most were mild and transient. Physician assessments including investigators' global assessments, lesion counts and erythema were evaluated in three-quarters of the studies, but time needed for improvement and duration of remission were incompletely or not reported.The quality of the body of evidence was rated moderate to high for most outcomes, but for some outcomes low to very low.Data for several outcomes could only be pooled for topical metronidazole and azelaic acid. Both were shown to be more effective than placebo in papulopustular rosacea (moderate quality evidence for metronidazole and high for azelaic acid). Pooled data from physician assessments in three trials demonstrated that metronidazole was more effective compared to placebo (risk ratio (RR) 1.98, 95% confidence interval (CI) 1.29 to 3.02). Four trials provided data on participants' assessments, illustrating that azelaic acid was more effective than placebo (RR 1.46, 95% CI 1.30 to 1.63). The results from three studies were contradictory on which of these two treatments was most effective.Two studies showed a statistically significant and clinically important improvement in favour of topical ivermectin when compared to placebo (high quality evidence). Participants' assessments in these studies showed a RR of 1.78 (95% CI 1.50 to 2.11) and RR of 1.92 (95% CI 1.59 to 2.32),which were supported by physicians' assessments. Topical ivermectin appeared to be slightly more effective than topical metronidazole for papulopustular rosacea, based on one study, for improving quality of life and participant and physician assessed outcomes (high quality evidence for these outcomes).Topical brimonidine in two studies was more effective than vehicle in reducing erythema in rosacea at all time points over 12 hours (high quality evidence). At three hours the participants' assessments had a RR of 2.21 (95% CI 1.52 to 3.22) and RR of 2.00 (95% CI 1.33 to 3.01) in favour of brimonidine. Physicians' assessments confirmed these data. There was no rebound or worsening of erythema after treatment cessation.Topical clindamycin phosphate combined with tretinoin was not considered to be effective compared to placebo (moderate quality evidence).Topical ciclosporin ophthalmic emulsion demonstrated effectiveness and improved quality of life for people with ocular rosacea (low quality evidence).Of the comparisons assessing oral treatments for papulopustular rosacea there was moderate quality evidence that tetracycline was effective but this was based on two old studies of short duration. Physician-based assessments in two trials indicated that doxycycline appeared to be significantly more effective than placebo (RR 1.59, 95% CI 1.02 to 2.47 and RR 2.37, 95% CI 1.12 to 4.99) (high quality evidence). There was no statistically significant difference in effectiveness between 100 mg and 40 mg doxycycline, but there was evidence of fewer adverse effects with the lower dose (RR 0.25, 95% CI 0.11 to 0.54) (low quality evidence). There was very low quality evidence from one study (assessed at high risk of bias) that doxycycline 100 mg was as effective as azithromycin. Low dose minocycline (45 mg) was effective for papulopustular rosacea (low quality evidence).Oral tetracycline was compared with topical metronidazole in four studies and showed no statistically significant difference between the two treatments for any outcome (low to moderate quality evidence).Low dose isotretinoin was considered by both the participants (RR 1.23, 95% CI 1.05 to 1.43) and physicians (RR 1.18, 95% CI 1.03 to 1.36) to be slightly more effective than doxycycline 50-100 mg (high quality evidence).Pulsed dye laser was more effective than yttrium-aluminium-garnet (Nd:YAG) laser based on one study, and it appeared to be as effective as intense pulsed light therapy (both low quality evidence). AUTHORS' CONCLUSIONS: There was high quality evidence to support the effectiveness of topical azelaic acid, topical ivermectin, brimonidine, doxycycline and isotretinoin for rosacea. Moderate quality evidence was available for topical metronidazole and oral tetracycline. There was low quality evidence for low dose minocycline, laser and intense pulsed light therapy and ciclosporin ophthalmic emulsion for ocular rosacea. Time needed to response and response duration should be addressed more completely, with more rigorous reporting of adverse events. Further studies on treatment of ocular rosacea are warranted.

Chick chorioallantoic membrane model for in ovo evaluation of timolol maleate-brimonidine tartrate ocular inserts.

The main aspire of this study was to develop ocular drug delivery system for dual drug glaucoma therapy by timolol maleate-brimonidine tartrate and endeavor the possibility of biocompatibility studies by in ova studies. Matrix type, both hydrophilic and lipophilic polymers, and reservoir-type ocular inserts of timolol maleate were prepared using hydrophilic polymers like polyvinyl alcohol, hydroxyl propyl methyl cellulose K4M and lipophilic polymers like ethylcellulose and eudragit S100 and were optimized. Based on the optimized formulation, triple-layered ocular inserts (reservoir type) of dual drug were prepared by solvent casting technique with an objective of reducing the frequency of administration, obtaining controlled release and greater therapeutic efficacy, preservative free dosage form for the treatment of glaucoma. FTIR spectral studies revealed no pharmaceutical incompatibility and no drug polymer interactions. Maximum drug release (99.18 ± 1.7) was achieved when PVP and HPMC K4M in 1:1 ratio with PEG 400 (0.3 ml) drug reservoir layer was sandwiched between ethyl cellulose as rate control membrane up to 32 h in a controlled fashion. Drug release was by non-Fickian diffusion mechanism for single drug formulation. But in dual drug insert, timolol maleate best fit into zero order and for brimonidine tartrate to Higuchi model and diffusion of drugs from this by non-Fickian diffusion mechanism. In ovo studies suggested that the optimized formulation was found to be sterile, biocompatible and physicochemically stable and support us to claim that the developed formulation was biocompatible.

The activity of lowering intraocular pressure of cassiae seed extract in a DBA/2J mouse glaucoma model.

PURPOSE: To evaluate the activity of lowering intraocular pressure (IOP) by Cassiae seed in the DBA/2J mouse glaucoma model. METHODS: Young male (mean age: 3 months) inherited glaucoma mice (BDA/2J) were enrolled in this study. To evaluate the potential of Cassiae seed in the treatment of glaucoma, all subjects were divided into 6 groups. There were 1 sham group, positive control identified as group 2 topical brimonidine and group 3 oral acetazolamide, and groups 4-6 Cassiae seed extract (CSE) groups. The lactate dehydrogenase (LDH) level in the anterior aqueous humor and the changes of IOP were investigated. Contents of total polyphenol glycosides in the CSE were measured using a high-performance liquid chromatography (HPLC) method. Chromatographic separation was performed on a Cosmosil 5C(18)-MS reverse-phase HPLC column (4.6×250-mm i.d., 5 µm) with methanol/0.1% H(3)PO(4) as the mobile phases in a gradient elution mode at a flow rate of 1.0 mL/min and an injection volume of 10 µL. The wavelength of UV detector was set at 254 nm. RESULTS: The LDH level in the anterior aqueous humor and IOP significantly decreased after treatment with CSE. The IOP-lowering effect of CSE was comparable to those of oral acetazolamide and brimonidine instillation. There were no abnormal findings in the external appearance, and body weight change after treatment with CSE for 5 weeks. Chrysophanol and physcion were measured by an HPLC method to obtain total polyphenol glycosides of the CSE, and were involved in the IOP-lowering function. CONCLUSION: Cassiae seed may be safe and beneficial for treating glaucoma due to its significant IOP- and LDH-lowering activities.

Evaluation of extended release brimonidine intravitreal device in normotensive rabbit eyes.

PURPOSE: To evaluate the safety profile of a brimonidine extended release intravitreal implant, in normotensive rabbit eyes. METHODS: Devices were made from hollow poly-l-lactic acid (PLA) tubes and contained hundred micrograms of brimonidine pamoate. Device was injected intravitreally in one eye of 12 New Zealand pigmented rabbits, whereas other eye was injected with a sham implant in masked fashion. Ocular examination was conducted at baseline and months 1, 3 and 6 including dilated fundus examination and electro-retinogram (ERG). Four rabbits were sacrificed at each time-point for retinal histology. ERG data were compared between groups and time-points using anova. RESULTS: No complications were reported from either eye of any rabbits over a 6-month period. Photopic A wave was reduced in the control eye at 1 month compared with baseline (p < 0.01). There was no significant difference in other ERG parameters between the groups at different time-points. Gross retinal histology was normal at all time-points. CONCLUSION: Extended release intravitreal brimonidine device was found to be safe and in normotensive rabbit eyes.

Microbead-induced ocular hypertensive mouse model for screening and testing of aqueous production suppressants for glaucoma.

PURPOSE: To characterize the microbead-induced ocular hypertension (OHT) mouse model and investigate its potential use for preclinical screening and evaluation of ocular hypotensive agents, we tested the model's responses to major antiglaucoma drugs. METHODS: Adult C57BL/6J mice were induced to develop OHT unilaterally by intracameral injection of microbeads. The effects of the most commonly used ocular hypotensive drugs, including timolol, brimonidine, brinzolamide, pilocarpine, and latanoprost, on IOP and glaucomatous neural damage were evaluated. Degeneration of retinal ganglion cells (RGCs) and optic nerve axons were quantitatively assessed using immunofluorescence labeling and histochemistry. Thickness of the ganglion cell complex (GCC) was also assessed with spectral-domain optical coherence tomography (SD-OCT). RESULTS: A microbead-induced OHT model promptly responded to drugs, such as timolol, brimonidine, and brinzolamide, that lower IOP through suppressing aqueous humor production and showed improved RGC and axon survival as compared to vehicle controls. Accordingly, SD-OCT detected significantly less reduction of GCC thickness in mice treated with all three aqueous production suppressants as compared to the vehicle contol-treated group. In contrast, drugs that increase aqueous outflow, such as pilocarpine and latanoprost, failed to decrease IOP in the microbead-induced OHT mice. CONCLUSIONS: Microbead-induced OHT mice carry dysfunctional aqueous outflow facility and therefore offer a unique model that allows selective screening of aqueous production suppressant antiglaucoma drugs or for studying the mechanisms regulating aqueous humor production. Our data set the stage for using GCC thickness assessed by SD-OCT as an imaging biomarker for noninvasive tracking of neuronal benefits of glaucoma therapy in this model.

The long-term outcomes of four alternative treatment strategies for primary open-angle glaucoma.

PURPOSE: To evaluate the long-term effects and costs of four treatment strategies for primary open-angle glaucoma compared to usual care. METHODS: Cost-effectiveness analyses with a lifelong horizon were made from a societal perspective. Data were generated with a patient-level model based on discrete event simulation. The model structure and parameter estimates were based on literature, particularly clinical studies on the natural course of glaucoma and the effect of treatment. We simulated heterogeneous cohorts of 3000 patients and explored the impact of uncertainty with sensitivity analyses. RESULTS: The incremental cost-effectiveness ratio (ICER) of initial treatment with a prostaglandin analogue compared with a ß-blocker was €12.931 per quality-adjusted life year (QALY) gained. A low initial target pressure (15 mmHg) resulted in 0.115 QALYs gained and €1550 saved compared to a gradual decrease from 21 to 15 mmHg upon progression. Visual field (VF) measurements every 6 rather than 12 months lead to health gains at increased costs (ICER €173,486 per QALY gained), whereas measurements every 24 months lead to health losses at reduced costs (ICER €21,516 per QALY lost). All treatment strategies were dominant over 'withholding treatment'. CONCLUSIONS: From a cost-effectiveness point of view, it seems advantageous to aim for a low intraocular pressure in all glaucoma patients. The feasibility of this strategy should therefore be investigated. Additionally, the cost-effectiveness outcomes of initiating monotherapy with a prostaglandin analogue and reducing the frequency of VF testing may be acceptable.