Effect of topical ophthalmic administration of 0.005% latanoprost solution on aqueous humor flow rate and intraocular pressure in ophthalmologically normal adult Beagles

OBJECTIVE

To determine the effect of topical ophthalmic administration of 0.005% latanoprost solution on aqueous humor flow rate (AHFR) and intraocular pressure (IOP) in ophthalmologically normal dogs.

ANIMALS

12 adult Beagles.

PROCEDURES

In a masked crossover design involving two 10-day experimental periods separated by a 7-day washout period, dogs were randomly assigned to first receive latanoprost or artificial tears (control) solution and then the opposite treatment in the later experimental period. Each experimental period was divided into a baseline phase (days 1 to 3), baseline fluorophotometry assessment (day 4), treatment phase (1 drop of latanoprost or artificial tears solution administered twice daily in each eye on days 5 to 9 and once on day 10), and posttreatment fluorophotometry assessment (day 10). Measured fluorescein concentrations were used to calculate baseline and posttreatment AHFRs. The IOP was measured 5 times/d in each eye during baseline and treatment (days 5 to 9) phases.

RESULTS

Mean baseline and posttreatment AHFR values did not differ significantly in either experimental period (latanoprost or control). In the latanoprost period, mean IOP was significantly lower during treatment than at baseline; there was no difference in corresponding IOP values during the control period. In the latanoprost period, mean IOP was significantly higher on the first day of treatment than on subsequent treatment days.

CONCLUSIONS AND CLINICAL RELEVANCE

In ophthalmologically normal dogs, topical ophthalmic administration of 0.005% latanoprost solution significantly decreased IOP but did not affect AHFR. Thus, the ocular hypotensive effect of latanoprost did not appear to have been caused by a reduction in aqueous humor production. (Am J Vet Res 2019;80:498-504).

Noninferiority of Preservative-free Versus BAK-preserved Latanoprost-timolol Fixed Combination Eye Drops in Patients With Open-angle Glaucoma or Ocular Hypertension

PRéCIS:: Noninferiority of efficacy was demonstrated for a preservative-free latanoprost-timolol fixed combination compared with a BAK-containing formulation at 84 days after treatment in patients with open-angle glaucoma or ocular hypertension.

PURPOSE

The purpose of this study was to compare the effect on intraocular pressure and safety of preservative-free latanoprost-timolol fixed combination (T2347) to benzalkonium chloride-preserved latanoprost-timolol fixed combination in patients with open-angle glaucoma or ocular hypertension.

METHODS

Phase III, randomized, parallel-group, investigator-masked study in 10 countries. A total of 242 patients aged 18 years or older with open-angle glaucoma or ocular hypertension in both eyes controlled with a preserved latanoprost-timolol fixed combination (15.7±2.4 mm Hg overall before inclusion) were randomized at day 0 with no washout period to receive the preservative-free alternative T2347 (N=127) or remain on the preserved comparator (N=115) for 84 days. Intraocular pressure changes from day 0 were measured at 9:00 am (±1 hour) on day 42 and day 84, and noninferiority of T2347 to the preserved comparator was analyzed statistically at day 84. Safety parameters were also reported.

RESULTS

The mean change in intraocular pressure from baseline to day 84 was -0.49±1.80 mm Hg for preservative-free T2347 and -0.49±2.25 mm Hg for the preserved comparator. These results met the noninferiority limits. Similar results were observed at day 42. There was no difference between groups in the incidence of adverse events or ocular signs. The total ocular symptoms score was better for T2347 than BPLT upon instillation at day 84 (45.9%/44.3%/9.8% of patients with improvement/no change/worsening vs. 33.6%/47.3%/19.1%; P=0.021), reflecting improvements in individual symptoms such as irritation/burning/stinging (P<0.001), and itching (P<0.01) on day 84.

CONCLUSIONS

Preservative-free latanoprost-timolol fixed combination T2347 showed noninferior efficacy compared with the preserved comparator and was well tolerated.

Rheological Properties, Dissolution Kinetics, and Ocular Pharmacokinetics of Loteprednol Etabonate (Submicron) Ophthalmic Gel 0.38

Purpose: To evaluate rheological properties, in vitro dissolution, and in vivo ocular pharmacokinetics of loteprednol etabonate (LE) (submicron) ophthalmic gel 0.38%. Methods: The viscosity of the LE gel 0.38% formulation was measured with a controlled stress rheometer. Dissolution kinetics were evaluated in a fixed-volume and flow-through assay. Rabbits received a single instillation of LE (submicron) gel 0.38% (both eyes), and concentrations of LE in ocular tissues were determined through 24 h by liquid chromatography with tandem mass spectrometry. Where indicated, comparators included micronized LE gel 0.38%, 0.5% (Lotemax® gel), and 0.75%. Results: LE (submicron) gel 0.38% exhibited shear-thinning characteristics similar to LE gel 0.5% with nearly identical yield stress. LE (submicron) gel 0.38% released 2.6-fold more LE into the dissolution medium than micronized LE gel 0.5% over 30 s in the fixed-volume dissolution assay, and submicron LE attained higher concentrations of dissolved LE than micronized LE gel 0.38% in the flow-through dissolution assay. In rabbits, the maximal concentration and area-under-the-curve over 24 h for LE in aqueous humor were 2.5- and 1.8-fold higher, respectively, for LE (submicron) gel 0.38% versus micronized LE gel 0.5% (both P < 0.001). Pharmacokinetic parameters were similar for most other tissues. Conclusions: LE (submicron) gel 0.38% demonstrated similar rheological properties to micronized LE gel 0.5% but faster dissolution, thus providing similar or higher LE concentrations in the aqueous humor, cornea, and iris-ciliary body after ocular dosing in rabbits despite a lowered concentration of drug in the formulation.

A randomized controlled trial of an online educational video intervention to improve glaucoma eye drop technique

OBJECTIVE

To determine the effectiveness of an online video intervention in improving self-efficacy and eye drop application technique in glaucoma patients.

METHODS

We randomized ninety-two patients with primary open-angle glaucoma, all who self-administer their eye drops, to either watch the 4-minute Meducation® eye drop technique video in the intervention group, or a nutrition video in the control group. We assessed five eye drop technique steps using objective video recordings at baseline, immediately after watching the video, and 1 month later. We used linear regression models to determine whether the intervention group had better self-efficacy and technique than the control group.

RESULTS

Adjusted for baseline technique and other covariates, eye drop technique averaged 0.73 steps better in intervention patients than controls immediately after the video (p = 0.003) and 0.63 steps better at 1 month (p = 0.01). Adjusted for baseline self-efficacy, intervention patients had better eye drop technique self-efficacy than controls immediately after the video (p = 0.02) and at 1 month (p = 0.02).

CONCLUSION

A short educational video can significantly improve glaucoma patients' short-term self-efficacy and eye drop technique.

PRACTICE IMPLICATIONS

Videos may provide an inexpensive, convenient way to deliver eye drop technique education in any provider's office or online.

A New Topical Eye Drop Containing LyeTxI-b, A Synthetic Peptide Designed from A Lycosa erithrognata Venom Toxin, Was Effective to Treat Resistant Bacterial Keratitis

Bacterial keratitis is an ocular infection that can lead to severe visual disability. Staphylococcus aureus is a major pathogen of the eye. We recently demonstrated the strong antimicrobial activity of LyeTxI-b, a synthetic peptide derived from a Lycosa erithrognatha toxin. Herein, we evaluated a topical formulation (eye drops) containing LyeTxI-b to treat resistant bacterial keratitis. Keratitis was induced with intrastromal injection of 4 × 10⁵ cells (4 µL) in New Zealand female white rabbits. Minimum inhibitory concentration (MIC) and biofilm viability were determined. LyeTxI-b ocular toxicity was evaluated through chorioallantoic membrane and Draize tests. One drop of the formulation (LyeTxI-b 28.9 µmol/L +0.5% CMC in 0.9% NaCl) was instilled into each eye four times a day, for a week. Slit-lamp biomicroscopy analysis, corneal histopathological studies and cellular infiltrate quantification through myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) detection were performed. LyeTxI-b was very effective in the treatment of keratitis, with no signs of ocular toxicity. Planktonic bacteria MIC was 3.6 µmol/L and LyeTxI-b treatment reduced biofilm viability in 90%. LyeTxI-b eliminated bacteria and reduced inflammatory cellular activity in the eyes. Healthy and treated animals showed similar NAG and MPO levels. LyeTxI-b is a potent new drug to treat resistant bacterial keratitis, showing effective antimicrobial and anti-inflammatory activity.

Prostaglandin analogues and nitric oxide contribution in the treatment of ocular hypertension and glaucoma

In patients with ocular hypertension or glaucoma, all treatments aim to lower intraocular pressure (IOP) by modulating aqueous humour (AH) production and/or uveoscleral and trabecular meshwork/Schlemm's canal AH drainage. PG analogues are considered to be the 'gold standard' treatment and are the most frequently used IOP-lowering agents. Recent data support an important role for NO in regulating IOP. Thus, novel PG analogues carrying a NO-donating moiety were recently advanced. Latanoprostene bunod (LBN) and NCX 470, NO-donating derivatives of latanoprost and bimatoprost, respectively, are examples of such compounds. LBN ophthalmic solution, 0.024% (Vyzulta™), showed greater IOP-lowering efficacy compared with that of Xalatan® (latanoprost ophthalmic solution, 0.005%) or 0.5% timolol maleate in clinical settings. NCX 470 was found to be more effective than bimatoprost in animal models of ocular hypertension and glaucoma. Selective EP2 receptor agonists (i.e. taprenepag isopropyl, omidenepag isopropyl and aganepag isopropyl) and non-selective prostanoid receptor agonists (i.e. ONO-9054, sepetaprost isopropyl) that concomitantly stimulate FP and EP3 receptors have also been shown to hold promise as effective IOP-lowering agents. LINKED ARTICLES: This article is part of a themed section on Eicosanoids 35 years from the 1982 Nobel: where are we now? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.8/issuetoc.

Enhancement of Retinal Function and of Neural Conduction Along the Visual Pathway Induced by Treatment with Citicoline Eye Drops in Liposomal Formulation in Open Angle Glaucoma: A Pilot Electrofunctional Study

INTRODUCTION

To evaluate the retinal function and the relative neural conduction along the visual pathway after treatment with citicoline in liposomal formulation (CLF) eye drops in patients with open angle glaucoma (OAG).

METHODS

Twelve OAG patients (mean age ± standard deviation 52.58 ± 11.39 years, intraocular pressure < 18 mmHg under topical hypotensive treatment, Humphrey field analyzer mean deviation - 4.49 ± 2.46 dB) were enrolled. Only one eye of studied patients was treated with CLF eye drops (OMK1-LF^®, Omikron Italia, 3 drops/day) (CLF group, 12 eyes) over a period of 4 months. In CLF eyes, pattern electroretinogram (PERG), visual evoked potentials (VEP), and visual field test were assessed at baseline and at the end of treatment (month 4).

RESULTS

After treatment with CLF eye drops, a significant increase of PERG P50-N95 amplitude and a significant shortening of VEP P100 implicit time were found. In CLF eyes, the shortening of VEP P100 implicit time was significantly correlated with the increase of PERG P50-N95 amplitude.

CONCLUSION

Data from this pilot study suggest that treatment with CLF eye drops induces an enhancement of the retinal bioelectrical responses (increase of PERG amplitude) with a consequent improvement of the bioelectrical activity of the visual cortex (shortening of VEP implicit time).

FUNDING

Omikron Italia S.r.l. and Opko Health Europe.

Ab interno trabecular bypass surgery with iStent for open-angle glaucoma

BACKGROUND

Glaucoma is a leading cause of irreversible blindness worldwide. In early stages, glaucoma results in progressive loss of peripheral (side) vision; in later stages, it results in loss of central vision leading to blindness. Elevated intraocular pressure (IOP) is the only known modifiable risk factor for glaucoma. Minimally invasive glaucoma surgical (MIGS) techniques, such as ab interno trabecular bypass surgery with iStent (Glaukos Corporation, Laguna Hills, CA, USA), have been introduced as a new treatment modality for glaucoma. However, the effectiveness of MIGS on keeping people 'drop-free' (i.e. not having to use eye drops to control IOP) and other outcomes is uncertain.

OBJECTIVES

To assess the effectiveness and safety of ab interno trabecular bypass surgery with iStent (or iStent inject) for open-angle glaucoma in comparison to conventional medical, laser, or surgical treatment.

SEARCH METHODS

Cochrane Eyes and Vision's Information Specialist searched the following databases on 17 August 2018: the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register; 2018, Issue 7), MEDLINE Ovid, Embase Ovid, the ISRCTN registry, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We applied no date or language restrictions. We searched the reference lists of reports from included studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that had compared iStent or iStent inject to medical therapy, laser treatment, conventional glaucoma surgery (trabeculectomy), or other MIGS procedures. We included RCTs that had compared iStent or iStent inject in combination with phacoemulsification to phacoemulsification alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently screened search results, assessed risk of bias, and extracted data from reports of included RCTs using an electronic data collection form.

MAIN RESULTS

We included seven RCTs (765 eyes of 764 participants; range per study 33 to 239 participants) that evaluated iStent in people with open-angle glaucoma. We also identified 13 studies that are ongoing or awaiting publications of results. Most participants in the included studies were women (417/764 (55%) participants) and older age (age range: 49 to 89 years). We assessed most trials at unclear or high risk of bias: four trials did not clearly report the method of generating the random sequence or concealing allocation; five were unmasked, open-label studies, which we assessed at high risk of bias for performance and detection bias. All seven trials were funded by the Glaukos Corporation. We graded the certainty of evidence as very low.Four RCTs compared iStent in combination with phacoemulsification to phacoemulsification alone. The summary estimate which we derived from two of the four RCTs suggested that participants in the iStent in combination with phacoemulsification group were 1.38 times more likely to be drop-free between six and 18 months than those in the phacoemulsification alone group (risk ratio (RR) 1.38, 95% confidence interval (CI) 1.18 to 1.63, I² = 67%). Data from two RCTs also suggested that iStent in combination with phacoemulsification compared to phacoemulsification alone may have offered a small reduction in number of IOP-lowering drops (mean difference (MD) -0.42 drops, 95% CI -0.60 to -0.23). It is uncertain whether there was any difference in terms of mean reduction in IOP from baseline (no meta-analysis).Two RCTs compared treatment with iStent to medical therapy; one of the two trials used the iStent inject. We determined the two trials to be clinically and methodologically heterogeneous and did not conduct a meta-analysis; however, the investigators of both trials reported that over 90% of participants in the treatment groups were drop-free compared to no participants in the medical therapy groups at six to 18 months.One RCT compared treatment with one versus two versus three iStents. There was no difference in terms of participants who were drop-free at 36 months or less; however, at longer follow-up (i.e. at 42 months) participants in the one iStent treatment were less likely to be drop-free than those in the two iStent (RR 0.51, 95% CI 0.34 to 0.75) or three iStent (RR 0.49, 95% CI 0.34 to 0.73) treatment groups. The study did not report the mean change in number of IOP-lowering drops.The type and timing of complications reported varied by RCTs. Similar proportions of participants who underwent treatment with iStent in combination with phacoemulsification and who underwent phacoemulsification alone needed secondary glaucoma surgery. None of RCTs reported findings related to quality of life.

AUTHORS' CONCLUSIONS

There is very low-quality evidence that treatment with iStent may result in higher proportions of participants who are drop-free or achieving better IOP control, in the short, medium, or long-term. Results from the 13 studies with results not yet available may clarify the benefits of treatment of people with iStent. Additionally, future MIGS studies should consider measuring quality of life and outcomes that reflect people's ability to perform vision-dependent activities.

Co-Delivery of Timolol and Brimonidine with a Polymer Thin-Film Intraocular Device

PURPOSE

We developed a polycaprolactone (PCL) co-delivery implant that achieves zero-order release of 2 ocular hypotensive agents, timolol maleate and brimonidine tartrate. We also demonstrate intraocular pressure (IOP)-lowering effects of the implant for 3 months in vivo.

METHODS

Two PCL thin-film compartments were attached to form a V-shaped co-delivery device using film thicknesses of ∼40 and 20 μm for timolol and brimonidine compartments, respectively. In vitro release kinetics were measured in pH- and temperature-controlled fluid chambers. Empty or drug-loaded devices were implanted intracamerally in normotensive rabbits for up to 13 weeks with weekly measurements of IOP. For ocular concentrations, rabbits were euthanized at 4, 8, or 13 weeks, aqueous fluid was collected, and ocular tissues were dissected. Drug concentrations were measured by liquid chromatography-tandem mass spectrometry.

RESULTS

In vitro studies show zero-order release kinetics for both timolol (1.75 μg/day) and brimonidine (0.48 μg/day) for up to 60 days. In rabbit eyes, the device achieved an average aqueous fluid concentration of 98.1 ± 68.3 ng/mL for timolol and 5.5 ± 3.6 ng/mL for brimonidine. Over 13 weeks, the drug-loaded co-delivery device resulted in a statistically significant cumulative reduction in IOP compared to untreated eyes (P < 0.05) and empty-device eyes (P < 0.05).

CONCLUSIONS

The co-delivery device demonstrated a zero-order release profile in vitro for 2 hypotensive agents over 60 days. In vivo, the device led to significant cumulative IOP reduction of 3.4 ± 1.6 mmHg over 13 weeks. Acceptable ocular tolerance was seen, and systemic drug levels were unmeasurable.

Analgesic Effect of a Single Drop of Nepafenac 0.3% on Pain Associated with Intravitreal Injections: A Randomized Clinical Trial

PURPOSE

To evaluate the analgesic effect of nepafenac 0.3% in patients undergoing intravitreal injections (IVI) of antivascular endothelial growth factors.

METHODS

This is a single-center, prospective, randomized, blinded, triple-arm, placebo-controlled interventional study. Patients were randomized into 3 Groups. Group 1 (n = 33) received nepafenac 0.1%, Group 2 (n = 32) received nepafenac 0.3%, and Group 3 (n = 31) received placebo 40 min before IVI. Using the short form of the McGill Pain Questionnaire (SF-MPQ), pain intensity was assessed with the visual analog scale (VAS), the Main Component of the SF-MPQ, and the present pain intensity (PPI) scores immediately and 6 h postinjection.

RESULTS

Immediately after IVI, the VAS pain score was statistically significantly lower in patients treated with nepafenac 0.1% and 0.3%, compared with placebo (P < 0.001 and P = 0.001, respectively). The PPI scores were statistically significantly lower when nepafenac 0.1% or 0.3% was instilled compared with placebo (P = 0.01 and P < 0.0001, respectively). The Main Component of the SF-MPQ scores were statistically significantly lower after nepafenac 0.1% and 0.3% administration compared with placebo (P = 0.001 and P < 0.001, respectively). Six hours post-IVI the nepafenac 0.3% demonstrated statistically significantly higher analgesic effect compared with nepafenac 0.1% and placebo as this was indicated by the VAS pain score (P = 0.013 and P < 0.00001, respectively) and by the PPI score (P = 0.01 and P < 0.00001, respectively).

CONCLUSIONS

A single instillation of nepafenac 0.1% or 0.3% before IVI could effectively alleviate the IVI-related pain. The 0.3% formula exerts its analgesic effect more intensively at 6 h after the IVI.

A review of Horner's syndrome in small animals

Horner's syndrome arises from dysfunction of the oculosympathetic pathway and is characterized by miosis, enophthalmos, protrusion of the third eyelid, and ptosis. It has been recognized in a wide variety of breeds and ages in small animal patients. The oculosympathetic pathway is a 3-neuron pathway. The central/first order neuron arises from the hypothalamus and extends down the spinal cord. The preganglionic/second order neuron arises from the first 3 thoracic spinal cord segments and travels through the thorax and cervical region until it synapses at the cranial cervical ganglion. The postganglionic/third order neuron travels from this ganglion to the orbit. Topical application of cocaine is the gold standard for differentiating Horner's syndrome from other causes of miosis. Topical 1% phenylephrine allows for identification of a post-ganglion Horner's syndrome. Numerous etiologies have been reported for Horner's syndrome, but idiopathic disease is most common. Ancillary diagnostics include otoscopic examination, thoracic radiographs, or advanced imaging. Treatment and prognosis are determined by the etiology.

Determination of the minimum protective dose of a glycoprotein-G-deficient infectious laryngotracheitis virus vaccine delivered via eye-drop to week-old chickens

Infectious laryngotracheitis (ILT) is an upper respiratory tract disease of chickens that is caused by infectious laryngotracheitis virus (ILTV), an alphaherpesvirus. This disease causes significant economic loses in poultry industries worldwide. Despite widespread use of commercial live attenuated vaccines, many poultry industries continue to experience outbreaks of disease caused by ILTV. Efforts to improve the control of this disease have resulted in the generation of new vaccine candidates, including ILTV mutants deficient in virulence factors. A glycoprotein G deletion mutant vaccine strain of ILTV (ΔgG ILTV), recently licenced as Vaxsafe ILT (Bioproperties Pty Ltd), has been extensively characterised in vitro and in vivo, but the minimum effective dose required to protect inoculated animals has not been determined. This study performed a vaccination and challenge experiment to determine the minimum dose of ΔgG ILTV that, when delivered by eye-drop to seven-day-old specific pathogen-free chickens, would protect the birds from a robust challenge with a virulent field strain of virus (class 9 ILTV). A dose of 10(3.8) plaque forming units was the lowest dose capable of providing a high level of protection against challenge, as measured by clinical signs of disease, tracheal pathology and virus replication after challenge. This study has shown that the ΔgG ILTV vaccine strain is capable of inducing a high level of protection against a virulent field virus at a commercially feasible dose. These results lay the foundations upon which a commercial vaccine can be developed, thereby offering the potential to provide producers with another important tool to help control ILTV.

Pythium insidiosum and Acanthamoeba keratitis in a contact lens user

The oomycete Pythium and the protozoan Acanthamoeba can cause fulminant and recalcitrant keratitis, respectively. These infections are not only sight-threatening but can also threaten the structural integrity of the eye. A high index of suspicion is required to identify Pythium keratitis given its uncommon occurrence. Acanthamoeba keratitis is most commonly associated with contact lens wear. However, its coexistence with Pythium has not been reported. We present the successful management of a case of contact lens-related keratitis, coinfected with Pythium and Acanthamoeba.

Topical axitinib is a potent inhibitor of corneal neovascularization

BACKGROUND

This study evaluated the effects of topically applied axitinib, a tyrosine kinase inhibitor, in an experimental model of corneal neovascularization (CNV).

METHODS

A total of 48 New Zealand rabbits were used. CNV was induced by placing five silk sutures in the upper cornea of one eye per rabbit. Rabbits were randomized into four groups (12 rabbits each): 0.9% saline (control group), 0.02 mg/mL axitinib, 0.35 mg/mL axitinib and 0.5 mg/mL axitinib groups. All treatments were administered three times daily for 14 days. Photographs were taken using a slit lamp on days 7 and 14. The area of neovascularization was measured in mm2 , as the percentage of total corneal area and as the percentage of corneal surface covered by sutures (SCS).

RESULTS

On day 14, the CNV area in the control group (31.50 ± 7.47 mm2 ; 115.00 ± 22.55% of the corneal SCS) was larger than that in the 0.02 mg/mL axitinib group (19.20 ± 8.92 mm2 ; 73.89 ± 34.98%), the 0.35 mg/mL axitinib group (8.83 ± 3.92 mm2 ; 31.90 ± 13.59%) and the 0.5 mg/mL axitinib group (5.12 ± 3.97 mm2 ; 18.38 ± 13.65%). Compared with saline, CNV was inhibited 39.04% by 0.02 mg/mL axitinib, 71.96% by 0.35 mg/mL axitinib and 84.73% by 0.5 mg/mL axitinib.

CONCLUSION

Topical administration of the three axitinib concentrations inhibited CNV in rabbits, blocking both vascular endothelial growth factor and platelet-derived growth factor pathways. Axitinib at 0.5 mg/mL induced profound inhibition of corneal angiogenesis.

Propranolol eye drops in patients with corneal neovascularization

RATIONALE

Studies performed in animal models of corneal neovascularization suggested the possible efficacy of a treatment with propranolol. Corneal neovascularization is one of the most feared complications of Stevens-Johnson syndrome that frequently involves ocular surface. We report the first 2 patients with severe ocular neo-vascularization treated with different degrees of success, with propranolol eye drops.

PATIENT CONCERNS

Two patients with corneal neovascularization complicating the Stevens-Johnson syndrome, not responsive to steroids and cyclosporine, were treated with propranolol eye drops.

DIAGNOSES

Corneal neovascularization was detected by ophthalmoscopic evaluation.

INTERVENTIONS

Topical treatment with propranolol eye drops at different concentrations.

OUTCOMES

Both patients reported dramatic subjective benefits (reduction of photophobia and discomfort) without adverse effects, and in the patient with a less advanced disease, an objective reduction of neovascularization and an improved visual acuity was observed.

LESSONS

This experience suggests that propranolol might be an inexpensive, safe and effective treatment in counteracting the progression of corneal neovascularization.

Release of Moxifloxacin From Corneal Collagen Shields

OBJECTIVES

To investigate the diffusion of moxifloxacin through bandage contact lenses (BCLs) versus corneal collagen shields (CSs), the relative ability of BCLs and CSs to release moxifloxacin, and the potential of release of moxifloxacin from CSs in the clinical setting.

METHODS

Using an in vitro model, the diffusion of 5% moxifloxacin across BCLs and CSs was compared. Next, the amount of drug release from BCLs and CSs soaked in 0.5% moxifloxacin was measured. Finally, based on a clinical model, CSs were soaked in Vigamox (commercial moxifloxacin) and the total concentration released was detected. Collagen shields remained intact after 24 hr; therefore, enzymatic digestion and mechanical grinding of the CS were performed to determine whether further drug could be released. The concentration of moxifloxacin was measured using a spectrophotometer at set time points up to 24 hr.

RESULTS

In the diffusion assay, 35.7±10.5% diffused through the BCLs and 36.2±11.8% diffused through the CSs (P=0.77). The absorption assay demonstrated at 120 min, a total of 33.3±6.77 μg/mL was released from BCLs compared with 45.8±5.2 μg/mL from the CSs (P=0.0008). In vitro experiments to simulate clinical application of Vigamox-soaked CS found the concentration of moxifloxacin released of 127.7±7.25 μg/mL in 2 mL of phosphate-buffered saline over 24 hr.

CONCLUSIONS

Moxifloxacin diffuses through BCLs and CSs at similar rates; however, CSs have greater capacity to absorb and release moxifloxacin compared with BCLs. Vigamox-soaked CSs released 250 μg of moxifloxacin and may be a useful method to prevent endophthalmitis.

Chitosan-Based In Situ Gels for Ocular Delivery of Therapeutics: A State-of-the-Art Review

Ocular in situ gels are a promising alternative to overcome drawbacks of conventional eye drops because they associate the advantages of solutions such as accuracy and reproducibility of dosing, or ease of administration with prolonged contact time of ointments. Chitosan is a natural polymer suitable for use in ophthalmic formulations due to its biocompatibility, biodegradability, mucoadhesive character, antibacterial and antifungal properties, permeation enhancement and corneal wound healing effects. The combination of chitosan, pH-sensitive polymer, with other stimuli-responsive polymers leads to increased mechanical strength of formulations and an improved therapeutic effect due to prolonged ocular contact time. This review describes in situ gelling systems resulting from the association of chitosan with various stimuli-responsive polymers with emphasis on the mechanism of gel formation and application in ophthalmology. It also comprises the main techniques for evaluation of chitosan in situ gels, along with requirements of safety and ocular tolerability.

Comparison of success rates in eye drop instillation between sitting position and supine position

Purpose

To compare the success rates of eye drop instillation in the sitting position and supine position among Japanese patients with ocular diseases (cataract, glaucoma, or retinal and vitreous diseases).

Methods

Patients who were hospitalized in Okayama University Hospital for eye surgery were studied. Instillation procedures of each patient in both the sitting and supine positions were recorded using a video camera at the time of instillation. We defined “success” when one drop fell accurately onto the ocular surface at the first attempt. Instillation of two or more drops, drops delivered to a site other than the eye surface, and touching the eyelashes, eyelids, or conjunctiva with the tip of the eye drop bottle were regarded as “failure”. We excluded patients with vision below counting finger.

Results

One-hundred and two patients (54 males and 58 females, aged 70.2 ± 12.3 years) with ocular disease who were hospitalized for surgery (cataract: 61.8%, glaucoma: 15.7%, retinal and vitreous diseases: 22.5%) were included in this prospective observational study. The mean duration of eye drop use was 3.1 ± 5.2 years. The success rate of eye drop instillation was significantly higher in the supine position than in the sitting position (64.7% vs. 50%, P = 0.0039). The mean age was significantly higher in the failure group than in the success group (74.0 ± 11.5 vs. 67.7 ± 12.4 years, P = 0.0085) for the sitting position, but not significantly different for the supine position (72.3 ± 12.9 vs. 70.1 ± 12.0 years, P = 0.3849). No significant differences in mean duration of drop use, mean corrected VA, and mean spherical equivalent refraction were observed between success and failure groups, for both sitting and supine positions.

Conclusions

In the present study, the success rate of eye drop instillation was significantly higher when applied in the supine position than in the sitting position.

Impact of Hyaluronic Acid-Containing Artificial Tear Products on Reepithelialization in an In Vivo Corneal Wound Model

PURPOSE

To evaluate the effect of 6 commercially available hyaluronic acid (HA)-containing topical artificial tear products on corneal reepithelialization following injury, in an in vivo mouse model.

METHODS

Ninety-six C57Bl/6 mice (16 per treatment group; male to female ratio, 1:1 per group) were anesthetized. Epithelial debridement was performed on 1 cornea per animal, and the debrided eye was imaged. A 30 μL masked test solution containing 1 of 6 artificial tear products was instilled, immediately on debridement, and subsequently, every 2 h, for a total of 4 administrations. At 24 h post debridement, corneas were stained with fluorescein and imaged to calculate corneal healing rate (number of fluorescein-negative corneas).

RESULTS

All 6 artificial tear products used in this study permitted the initial process of corneal wound healing. However, the corneal reepithelialization rate after 24 h was higher with Hydroxypropyl guar (HPG)/HA (53.33%) compared with other HA-containing artificial tear products [HA1 (12.5%), HA2 (26.67%), HA3 (31.25%), HA4 (6.25%), and HA5 (43.75%)]. The average area and percentage area of reepithelialization after 24 h were also higher with HPG/HA compared with other treatment groups.

CONCLUSIONS

Percentage of eyes with complete corneal reepithelialization 24 h post debridement was highest with HPG/HA compared with other HA-containing artificial tear products tested. The results of this study provide additional evidence on the potential benefits of HPG/HA in the management of dry eye and its role in the rapid restoration of a healthy ocular epithelium. However, further studies are required to confirm the effects on human corneal wounds.

Adenovirus-related epidemic keratoconjunctivitis outbreak at a hospital-affiliated ophthalmology clinic

Adenovirus-associated epidemic keratoconjunctivitis (A-EKC) is a cause of large and prolonged outbreaks in ophthalmology clinics and can result in substantial morbidity. A-EKC outbreaks are often the result of contaminated ophthalmologic equipment, surfaces, or hands. Contaminated multidose eye drops are also a likely culprit, but few prior studies provide clear epidemiologic evidence that adenovirus transmission resulted from contamination of eye drops. We describe an A-EKC outbreak at a large, hospital-affiliated eye clinic that affected 44 patients. The unique epidemiology of the outbreak provides strong evidence that contaminated multidose dilating eye drops resulted in adenovirus transmission. Removal of multidose eye medication from the clinic, combined with case finding, enhanced infection control and enhanced environmental cleaning, led to rapid control of the outbreak.

Prospective, Randomized, Single Masked, Parallel Study Exploring the Effects of a Preservative-Free Ophthalmic Solution Containing Hyaluronic Acid 0.4% and Taurine 0.5% on the Ocular Surface of Glaucoma Patients Under Multiple Long-Term Topical Hypotensive Therapy

INTRODUCTION

To compare the effects of a preservative-free (PF) ophthalmic solution containing hyaluronic acid (HA) 0.4% and taurine (TAU) 0.5% with those of a PF ophthalmic solution containing HA 0.2% on ocular surface signs, symptoms, and morphological parameters in glaucoma patients under multiple long-term topical hypotensive therapy.

METHODS

Eligible patients underwent evaluation of ocular surface parameters by ocular surface disease index (OSDI) and glaucoma symptom scale (GSS) questionnaires, breakup time test (BUT), Schirmer I test, corneal and conjunctival staining (Oxford scale), and conjunctival in vivo confocal microscopy (Heidelberg Retina Tomograph 3, Heidelberg Engineering GmbH, Heidelberg, Germany). After the baseline visit, patients were randomized to use a PF ophthalmic solution containing HA 0.4% and TAU 0.5%, QID, in both eyes (group 1) or to use a PF ophthalmic solution containing HA 0.2%, QID (group 2) in addition to the ongoing preserved hypotensive treatment. Follow-up visits were scheduled at 30 and 90 days.

RESULTS

Thirty-nine eyes of 39 glaucoma patients were included in the study. At baseline, results of study tests of both groups were similar. After 90 days in group 1 the BUT (p = 0.01), the Oxford score (p = 0.03), the conjunctival goblet cells (CGC) density (p = 0.0005) ,and the two questionnaires score significantly improved (OSDI, p = 0.003; GSS, p = 0.003) compared to baseline values, while in group 2 all these parameters did not differ from baseline (BUT, p = 0.39; Oxford score, p = 0.54; CGC density, p = 0.33, OSDI p = 0.65, GSS, p = 0.25). The BUT and the CGC density were statistically different between groups both at 30 and 90 days (p = 0.04 and p = 0.04, respectively). The Schirmer I test did not statistically change after 90 days in both groups.

CONCLUSIONS

The PF ophthalmic solution with HA 0.4% and TAU 0.5% seems to improve CGC density and reduce signs and symptoms of dry eye in glaucoma patients under long-term multiple preserved hypotensive therapy.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03480295.

Atopic keratoconjunctivitis: A diagnostic dilemma-a case report

RATIONALE

Atopic keratoconjunctivitis (AKC) remains a difficult diagnosis despite advances in imaging technologies. This is a case study of the diagnostic and treatment course for a patient with AKC.

PATIENT CONCERNS

A 15-year-old male complained of progressively increasing pain, redness, watering and blurred vision in the right eye. The medical history showed that the patient suffered from itching on the hands, knees, neck and the eye skin one year before the onset of initial symptoms in the affected eye.

DIAGNOSES

A final diagnosis of stage III AKC with atopic dermatitis (AD) was reached.

INTERVENTIONS

The patient was used 0.1% tacrolimus eye drops and 0.3% gatifloxacin eye gel after antimicrobial susceptibility test was performed. In the presence of AD, 0.1% mometasone furoate cream and 0.03% tacrolimus ointment were applied twice daily.

OUTCOMES

One month after starting treatment, the conjunctivitis and corneal ulcer rapidly improved along with reduced lid papillae. Macular grade corneal opacity was noticed with minimal thinning. The AD also rapidly improved. At the end of two months patient was asymptomatic with a significant improvement in his quality of life.

LESSONS

Proper diagnosis of AKC especially when associated with dermatological signs along with management of AD in conjunction with dermatologist is necessary to prevent corneal involvement which can cause permanent visual disability is of utmost importance. We also noticed that topical tacrolimus is a good option for the treatment of severe AKC with AD along with systemic immunosupressants.

New observation of microcystic macular edema as a mild form of cystoid macular lesions after standard phacoemulsification: Prevalence and risk factors

We present the new observations of postoperative microcystic macular edema (MME) as a mild form of cystoid macular lesions (CMLs) after standard phacoemulsification.To report the incidence, risk factors, and pathophysiology of MME compared to conventional concept of pseudophakic cystoid macular edema (CME), we retrospectively reviewed patients' records. Pseudophakic CMLs were defined as any cystic fluid collections that were newly formed after cataract surgery, confirmed by preoperative and postoperative optical coherence tomography (OCT) examinations. CMLs were classified into 2 groups, which are CME and MME, according to the change the central retinal thickness. The dataset consisted of 316 patients (mean age, 67.52 ± 12.95 years; range, 42-87 years). Topical nonsteroidal anti-inflammatory drug (NSAID) were administered in 197 eyes during the perioperative period; 147 eyes were not treated. CMLs were present in 22 out of 344 (6.39%) eyes. Six of 344 eyes (1.74%) had CME and 16 of 344 eyes (4.65%) had MME. The incidence of MME significantly decreased in the group of patients treated with topical NSAIDs (P = .039), while the incidence of CME was not different in both groups (P = .408). All of the patients with MME were experienced improvement with only topical NSAIDs. However, 67% (4/6) of patients with CME did not improve with topical NSAIDs alone and needed additional treatments. Pseudophakic MMEs were more likely to have a history of diabetic retinopathy, epiretinal membrane, and eyes were not treated with topical NSAID.This study showed a wide clinical spectrum of CMLs. MME has not been included in the conventional definition of pseudophakic CME. Topical NSAIDs could decrease the CML incidence. People with risk factors for CML should use topical NSAIDs and undergo regular follow-up OCT examinations.