Clinical Treatment of Dry Eye Using 0.03% Tacrolimus Eye Drops

Purpose: To report the clinical outcome of the treatment of dry eyes using 0.03% tacrolimus eye drops (olive oil + tacrolimus 0.03%) (Ophthalmos, Sao Paulo, Brazil). Methods: Sixteen eyes of 8 patients with Sjogren syndrome dry eyes (age, 51.13 +/- 9.45 years) were enrolled in this study (prospective noncontrolled interventional case series). Patients were instructed to use topical 0.03% tacrolimus eye drops twice a day (every 12 hours) in the lower conjunctival sac. Schirmer I test, break-up time, corneal fluorescein, and rose bengal staining score were performed in all patients 1 day before, and 14, 28, and 90 days after treatment with 0.03% tacrolimus eye drops. Results: The average fluorescein staining and rose bengal staining scores improved statistically significantly after 14 days of treatment and improved even more after 28 and 90 days. The average Schirmer I test did not improve statistically significantly after 28 days of treatment, although we did observe a significant improvement after 90 days of treatment with 0.03% tacrolimus eye drops. The average break-up time did not improve statistically after 14 days of treatment, although we observed a significant improvement after 28 and 90 days of treatment with 0.03% tacrolimus eye drops. Conclusions: Topical 0.03% tacrolimus eye drops successfully improved tear stability and ocular surface status in patients with dry eyes.

Towards an improved ocular drug delivery system

The ultimate aim of this project was to design new biomaterials which will improve the efficiency of ocular drug delivery systems. Initially, it was necessary to review the information available on the nature of the tear fluid and its relationship with the eye. An extensive survey of the relevant literature was made. There is a common belief in the literature that the ocular glycoprotein, mucin, plays an important role in tear film stability, and furthermore, that it exists as an adherent layer covering the corneal surface. If this belief is true, the muco-corneal interaction provides the ideal basis for the development of sustained release drug delivery. Preliminary investigations were made to assess the ability of mucin to adhere to polymer surfaces. The intention was to develop a synthetic model which would mimic the supposed corneal/mucin interaction. Analytical procedures included the use of microscopy (phase contrast and fluorescence), fluorophotometry, and mucin-staining dyes. Additionally, the physical properties of tears and tear models were assessed under conditions mimicking those of the preocular environment, using rheological and tensiometric techniques. The wetting abilities of these tear models and opthalmic formulations were also investigated. Tissue culture techniques were employed to enable the surface properties of the corneal surface to be studied by means of cultured corneal cells. The results of these investigations enabled the calculation of interfacial and surface characteristics of tears, tear models, and the corneal surface. Over all, this work cast doubt on the accepted relationship of mucin with the cornea. A corneal surface model was designed, on the basis of the information obtained during this project, which would possess similar surface chemical properties (i.e. would be biomimetic) to the more complex original. This model, together with the information gained on the properties of tears and solutions intended for ocular instillation, could be valuable in the design of drug formulations with enhanced ocular retention times. Furthermore, the model itself may form the basis for the design of an effective drug-carrier.

Assessment of ocular surface toxicity after topical instillation of nitric oxide donors

PURPOSE: To evaluate the ocular surface toxicity of two nitric oxide donors in ex vivo and in vivo animal models: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylcysteine (SNAC) in a hydroxypropyl methylcellulose (HPMC) matrix at final concentrations 1.0 and 10.0 mM. METHODS: Ex vivo GSNO and SNAC toxicities were clinically and histologically analyzed using freshly excised pig eyeballs. In vivo experiments were performed with 20 albino rabbits which were randomized into 4 groups (5 animals each): Groups 1 and 2 received instillations of 150 µL of aqueous HPMC solution containing GSNO 1.0 and 10.0 mM, respectively, in one of the eyes; Groups 3 and 4 received instillations of 150 µL of aqueous HPMC solution-containing SNAC 1.0 and 10.0 mM, respectively, in one of the eyes. The contralateral eyes in each group received aqueous HPMC as a control. All animals underwent clinical evaluation on a slit lamp and the eyes were scored according to a modified Draize eye test and were histologically analyzed. RESULTS: Pig eyeballs showed no signs of perforation, erosion, corneal opacity or other gross damage. These findings were confirmed by histological analysis. There was no difference between control and treated rabbit eyes according to the Draize eye test score in all groups (p>0.05). All formulations showed a mean score under 1 and were classified as non-irritating. There was no evidence of tissue toxicity in the histological analysis in all animals. CONCLUSION: Aqueous HPMC solutions containing GSNO and SNAC at concentrations up to 10.0 mM do not induce ocular irritation.

Ocular distribution, spectrum of activity, and in vivo viral neutralization of a fully humanized anti-herpes simplex virus IgG Fab fragment following topical application.

Herpes simplex ocular infection is a major cause of corneal blindness. Local antiviral treatments exist but are associated with corneal toxicity, and resistance has become an issue. We evaluated the biodistribution and efficacy of a humanized anti-herpes simplex virus (anti-HSV) IgG FAb fragment (AC-8; 53 kDa) following repeated topical administration. AC-8 was found in the corneal epithelium, anterior stroma, subepithelial stromal cells, and retinal glial cells, with preferential entry through the ocular limbus. AC-8 was active against 13 different strains of HSV-1, with 50% and 90% mean effective concentrations (MEC(50) and MEC(90), respectively) ranging from 0.03 to 0.13 μg/ml, indicating broad-spectrum activity. The in vivo efficacy of AC-8 was evaluated in a mouse model of herpes-induced ocular disease. Treatment with low-dose AC-8 (1 mg/ml) slightly reduced the ocular disease scores. A greater reduction of the disease scores was observed in the 10-mg/ml AC-8-treated group, but not as much as with trifluridine (TFT). AC-8 treatment reduced viral titers but less than trifluridine. AC-8 did not display any toxicity to the cornea or other structures in the eye. In summary, topical instillation of an anti-HSV FAb can be used on both intact and ulcerated corneas. It is well tolerated and does not alter reepithelialization. Further studies to improve the antiviral effect are needed for AC-8 to be considered for therapeutic use.

Ultrasound assessment of ocular vascular effects of repeated intravitreal injections of ranibizumab for wet age-related macular degeneration.

PURPOSE: Determine the effect of repeated intravitreal injections of ranibizumab (0.5 mg; 0.05 ml) on retrobulbar blood flow velocities (BFVs) using ultrasound imaging quantification in twenty patients with exudative age-related macular degeneration treated for 6 months. METHODS: Visual acuity (ETDRS), central macular thickness (OCT), peak-systolic, end-diastolic and mean-BFVs in central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries were measured before, 2 days, 3 weeks and 6 months after the first injection. Patients were examined monthly and received 1-5 additional injections depending on ophthalmologic examination results. RESULTS: Six months after the first injection, a significant increase in visual acuity 50.9 ± 25.9 versus 44.4 ± 21.7 (p < 0.01) and decrease in mean central macular thickness 267 ± 74 versus 377 ± 115 μm (p < 0.001) were observed compared to baseline. Although mean-BFVs decreased by 16%±3% in CRA and 20%±5% in TPCA (p < 0.001) 2 days after the first injection, no significant change was seen thereafter. Mean-BFVs in OA decreased by 19%±5% at week 3 (p < 0.001). However, the smallest number of injections (two injections) was associated with the longest time interval between the last injection and month 6 (20 weeks) and with the best return to baseline levels for mean-BFVs in CRA, suggesting that ranibizumab had reversible effects on native retinal vascular supply after its discontinuation. Moreover, a significant correlation between the number of injections and percentage of changes in mean-BFVs in CRA was observed at month 6 (R = 0.74, p < 0.001) unlike TPCA or OA. CONCLUSION: Ranibizumab could impair the native choroidal and retinal vascular networks, but its effect seems reversible after its discontinuation.

Ultrasound assessment of ocular vascular effects of repeated intravitreal injections of ranibizumab for wet age-related macular degeneration.

PURPOSE: Determine the effect of repeated intravitreal injections of ranibizumab (0.5 mg; 0.05 ml) on retrobulbar blood flow velocities (BFVs) using ultrasound imaging quantification in twenty patients with exudative age-related macular degeneration treated for 6 months. METHODS: Visual acuity (ETDRS), central macular thickness (OCT), peak-systolic, end-diastolic and mean-BFVs in central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries were measured before, 2 days, 3 weeks and 6 months after the first injection. Patients were examined monthly and received 1-5 additional injections depending on ophthalmologic examination results. RESULTS: Six months after the first injection, a significant increase in visual acuity 50.9 ± 25.9 versus 44.4 ± 21.7 (p < 0.01) and decrease in mean central macular thickness 267 ± 74 versus 377 ± 115 μm (p < 0.001) were observed compared to baseline. Although mean-BFVs decreased by 16%±3% in CRA and 20%±5% in TPCA (p < 0.001) 2 days after the first injection, no significant change was seen thereafter. Mean-BFVs in OA decreased by 19%±5% at week 3 (p < 0.001). However, the smallest number of injections (two injections) was associated with the longest time interval between the last injection and month 6 (20 weeks) and with the best return to baseline levels for mean-BFVs in CRA, suggesting that ranibizumab had reversible effects on native retinal vascular supply after its discontinuation. Moreover, a significant correlation between the number of injections and percentage of changes in mean-BFVs in CRA was observed at month 6 (R = 0.74, p < 0.001) unlike TPCA or OA. CONCLUSION: Ranibizumab could impair the native choroidal and retinal vascular networks, but its effect seems reversible after its discontinuation.

A poloxamer/chitosan in situ forming gel with prolonged retention time for ocular delivery

The aim of the present work was to obtain an ophthalmic delivery system with improved mechanical and mucoadhesive properties that could provide prolonged retention time for the treatment of ocular diseases. For this, an in situ forming gel comprised of the combination of a thermosetting polymer, poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) (PEO-PPO-PEO, poloxamer), with a mucoadhesive agent (chitosan) was developed. Different polymer ratios were evaluated by oscillatory rheology, texture and mucoadhesive profiles. Scintigraphy studies in humans were conduced to verify the retention time of the formulations developed. The results showed that chitosan improves the mechanical strength and texture properties of poloxamer formulations and also confers mucoadhesive properties in a concentration-dependent manner. After a 10-min instillation of the poloxamer/chitosan 16:1 formulation in human eyes, 50-60% of the gel was still in contact with the cornea surface, which represents a fourfold increased retention in comparison with a conventional solution. Therefore, the developed formulation presented adequate mechanical and sensorial properties and remained in contact with the eye surface for a prolonged time. In conclusion, the in situ forming gel comprised of poloxamer/chitosan is a promising tool for the topical treatment of ocular diseases. (C) 2010 Elsevier B.V. All rights reserved.

Serial heart rate changes in rats inoculated by conjunctival instillation of Trypanosoma cruzi obtained from bug faeces

The cardiac effects of experimentally induced myocarditis, when the parasite is obtained from mouse blood, are well known. However, the consequences of the infection when the parasites are obtained from bug faeces are less well defined. In the present investigation, we have used the "Y" strain of Trypanosoma cruzi, which was maintained in Rhodnius prolixus by repeated passages in mice. The faeces of 30 infected bugs were collected, the number of parasites counted and 4,000 parasites inoculated by the conjunctival route in 60 rats. Twenty-nine other rats received faeces from noninfected bugs (sham-inoculated controls) and 40 were used as normal controls. The heart rate of the three groups of animals was recorded under general anesthesia with ether. The heart rate, at day 0 pre-inoculation, was similar in the three groups of animals (Controls: 379 ± 27 beats/min Mean ± SD; Sham-inoculated: 366 ± 31; Infected: 351 ± 29) (p> 0.05). In the infected animals, the mean heart rate began to increase significantly by day 12 following infection (375 ± 31), reaching the highest values between days 18 (390 ± 33) and 21 (403 ± 33) and returned to baseline by day 30 (359 ± 28) (p< 0.05). The heart rate changes were statistically different from those observed in the sham-inoculated controls and in the control animals. Therefore, these heart rate changes were provoked by the Trypanosoma cruzi-induced infection. Thus, it appears that irrespective of the source of the parasite and route of inoculation Trypanosoma cruziacute infection provokes a transient sinus tachycardia.

Novel micelle carriers for cyclosporin A topical ocular delivery: in vivo cornea penetration, ocular distribution and efficacy studies.

Cornea transplantation is one of the most performed graft procedures worldwide with an impressive success rate of 90%. However, for "high-risk" patients with particular ocular diseases in addition to the required surgery, the success rate is drastically reduced to 50%. In these cases, cyclosporin A (CsA) is frequently used to prevent the cornea rejection by a systemic treatment with possible systemic side effects for the patients. To overcome these problems, it is a challenge to prepare well-tolerated topical CsA formulations. Normally high amounts of oils or surfactants are needed for the solubilization of the very hydrophobic CsA. Furthermore, it is in general difficult to obtain ocular therapeutic drug levels with topical instillations due to the corneal barriers that efficiently protect the intraocular structures from foreign substances thus also from drugs. The aim of this study was to investigate in vivo the effects of a novel CsA topical aqueous formulation. This formulation was based on nanosized polymeric micelles as drug carriers. An established rat model for the prevention of cornea graft rejection after a keratoplasty procedure was used. After instillation of the novel formulation with fluorescent labeled micelles, confocal analysis of flat-mounted corneas clearly showed that the nanosized carriers were able to penetrate into all corneal layers. The efficacy of a 0.5% CsA micelle formulation was tested and compared to a physiological saline solution and to a systemic administration of CsA. In our studies, the topical CsA treatment was carried out for 14 days, and the three parameters (a) cornea transparency, (b) edema, and (c) neovascularization were evaluated by clinical observation and scoring. Compared to the control group, the treated group showed a significant higher cornea transparency and significant lower edema after 7 and 13 days of the surgery. At the end point of the study, the neovascularization was reduced by 50% in the CsA-micelle treated animals. The success rate of cornea graft transplantation was 73% in treated animals against 25% for the control group. This result was as good as observed for a systemic CsA treatment in the same animal model. This new formulation has the same efficacy like a systemic treatment but without the serious CsA systemic side effects. Ocular drug levels of transplanted and healthy rat eyes were dosed by UPLC/MS and showed a high CsA value in the cornea (11710 ± 7530 ng(CsA)/g(tissue) and 6470 ± 1730 ng(CsA)/g(tissue), respectively). In conclusion, the applied formulation has the capacity to overcome the ocular surface barriers, the micelles formed a drug reservoir in the cornea from, where a sustained release of CsA can take place. This novel formulation for topical application of CsA is clearly an effective and well-tolerated alternative to the systemic treatment for the prevention of corneal graft rejection.

Short and longterm ocular vascular effects after intravitreal injection of ranibizumab for neovascular age-related macular degeneration

Purpose: To investigate the effect of the first and repeated intravitreal injections of ranibizumab (1.25mg; 0.05ml) on retrobulbar blood flow velocities in patients with wet age-related macular degeneration (AMD). Methods: This prospective non randomized study included twenty consecutive AMD patients. Time- averaged mean blood flow velocities (BFVs) in the central retinal, temporal posterior ciliary and ophthalmic arteries (CRA, TPCA and OA) were measured by ultrasound imaging before, 2 days and 3 weeks after the first injection of ranibizumab, then 6 months after supplemental monthly injections if required. At each visit, complete ophthalmological examination was performed, including best corrected visual acuity measurement according to ETDRS protocol and OCT. Results: In the treated eyes, ranibizumab injection was followed by a significant improvement in visual acuity (from 44.4 ± 21.7, to 50.9±25.9 (p<0.01) at month 6, and a decrease in mean central macular thickness from 377±115 to 267 ± 74 µm (p<0.001) at month 6. At day 2 mean BFVs decreased by 16% in the CRA and by 20% in TPCA (p<0.001, both), then remained stable. Mean BFVs did not change in OA at the day 2 but decreased at week 3 by 18% (p<0.001). Supplemental injections did not lead to additional effects at month 6. No effect was tabulated in the fellow eye. Conclusions: We report an early decrease in mean BFV in CRA and TPRA following intravitreal injections of ranibizumab corresponding to vasoconstrictive effect of this drug. Decrease in mean BFV in all retrobulbar arteries from the week 3 suggests that ranibizumab proceeds to a local and regional vasoconstrictive and antiangiogenic effects after local diffusion. Thus, ranibizumab could induce an actual hypoperfusion of the treated eye which could correspond to a vascular side effect.

The influence of a certain volume of fluid in the lower tear meniscus on intraocular pressure measurements using the non-contact tonometer

Background: Intraocular pressure (IOP) is the pressure inside the eye that helps to maintain the integrity and the suitable form of the ocular globe. Precise and accurate measures of IOP are needed for the diagnosis as well as follow-up of glaucoma. In daily clinical practice, Goldmann applanation tonometer (GAT) and Non-contact tonometer (NCT) are the most common devices for measuring IOP. A close agreement between these methods has been showed, particularly in normotensive patients and a poor agreement, especially when IOP levels are above the normal range. Ophthalmologists have noticed a poor agreement between NCT and GAT, observing that by using NCT and after comparing with GAT, there is an overestimation of IOP readings, and particularly it occurs when the eyes are tearful. Previous studies investigate the effect of tears in Non-contact tonometer readings by the instillation of artificial tears, concluding in one of the studies that the variation was less than 1mmHg and not clinically significant, in contrast with another study which the increases were sadistically significant. Tear menisci are a thin strip of tear fluid located between the bulbar conjunctiva and the eyelid margins. We think that the overestimation of IOP readings using NCT could be due to the presence of a higher volume of tear in the lower tear meniscus which might cause an optical interference in the optoelectronic applanation monitoring system of this deviceObjectives: To research the influence of a certain volume of fluid in the lower tear meniscus on IOP measurements using the NCT in healthy eyes. Moreover, to investigate the agreement between IOP readings obtained by NCT and GAT in the presence and absence of this volume of fluidMethods: The study design will be transversal for diagnostic tests of repeated measures. We will study patients with no ocular pathology and IOP<21mmHg. It will consist in the measurement of IOP using NCT before and after the instillation of COLIRCUSÍ FLUOTEST, used as a volume of fluid in the lower tear meniscus, to observe if there will be differences using the paired t-test. Moreover, we will take IOP measures by GAT in order to know the agreement between these methods after and before the application of these eyedrops, using the ICC (intraclass correlation coefficient) and the Bland-Altmann method

Citología de impresión para neoplasias de la superficie ocular

Se estimó la sensibilidad y especificidad de la citología de impresión como prueba diagnóstica en lesiones conjuntivales clínicamente sospechosas de neoplasia usando como patrón de oro la patología. Se estudiaron 60 pacientes, que ingresaron al azar a la Fundación Oftalmológica Nacional, con diagnóstico clínico de neoplasia de superficie ocular o lesión sospechosa de neoplasia, quienes fueron sometidos a citología de impresión y posterior resección quirúrgica completa, más estudio patológico de la lesión. Se realizó un análisis descriptivo, analizando la sensibilidad y la especificidad con el método clásico y análisis bayesiano.

Effect of polymerization and accelerated aging on iris color stability of ocular prosthesis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alteration of blue pigment in artificial iris in ocular prosthesis: Effect of paint, drying method and artificial aging

The artificial iris is the structure responsible for the dissimulation and aesthetics of ocular prosthesis. The objective of the present study was to evaluate the color stability of artificial iris of microwaveable polymerized ocular prosthesis, as a function of paint type, drying method and accelerated aging. A total of 40 discs of microwaveable polymerized acrylic resin were fabricated, and divided according to the blue paint type ( n = 5): hydrosoluble acrylic, nitrocellulose automotive, hydrosoluble gouache and oil paints. Paints where dried either at natural or at infrared light bulb method. Each specimen was constituted of one disc in colorless acrylic resin and another colored with a basic sclera pigment. Painting was performed in one surface of one of the discs. The specimens were submitted to an artificial aging chamber under ultraviolet light, during 1008 h. A reflective spectrophotometer was used to evaluate color changes. Data were evaluated by 3-way repeated-measures ANOVA and the Tukey HSD test (alpha = 0.05). All paints suffered color alteration. The oil paint presented the highest color resistance to artificial aging regardless of drying method. (C) 2010 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Efeitos da instilação de morfina na inflamação ocular induzida experimentalmente em coelhos

Pós-graduação em Cirurgia Veterinária - FCAV