INTRAVITREAL DEXAMETHASONE IMPLANT IN RETINITIS PIGMENTOSA-RELATED CYSTOID MACULAR EDEMA.

PURPOSE: To report the clinical outcome after intravitreal dexamethasone implant in patients with retinitis pigmentosa and cystoid macular edema. METHODS: Multicenter retrospective case series of eyes with retinitis pigmentosa and cystoid macular edema that underwent intravitreal dexamethasone implant. Primary outcome measures were best-corrected visual acuity in LogMAR and central macular thickness. Statistical analyses used two-tailed comparison with Wilcoxon signed-rank test. RESULTS: There were a total of 45 eyes from 34 patients with a mean age of 32.7 years (range 16-57) and mean follow-up of 15.5 ± 13.0 months. At Month 3 after the first injection, mean initial best-corrected visual acuity improved from 0.61 ± 0.38 (20/81) to 0.37 ± 0.16 (20/47) (P = 0.012), whereas mean central macular thickness (µm) decreased from 506 ± 288 µm to 311.7 ± 71.6 µm (P < 0.001) and mean intraocular pressure increased from 15.7 ± 2.3 mmHg to 19.8 ± 11.0 mmHg (P = 0.01). Fourteen eyes had multiple injections (1-7 reinjections) at a mean interval of 6 months. Treatment effect was durable with multiple injections, but with seven eyes developing visually significant cataracts. CONCLUSION: Best-corrected visual acuity improved up to 4 months in around half of the eyes. Eyes that benefited the most were pseudophakic, steroid nonresponsive, with large initial central macular thickness, and profuse fluorescein dye leakage.

Evaluation of allergic sensitization in Lebanese patients with allergic conjunctivitis.

PURPOSE: To describe the profile of patients with allergic conjunctivitis (AC) regarding their demographics, symptomatology and specific allergen sensitization, in a Lebanese tertiary hospital. METHODS: Cross-sectional study conducted at the Hôtel-Dieu de France hospital (Beirut, Lebanon) during a period of 18 months. Patients with seasonal or perennial AC presenting for ophthalmic consultation had measurements of total and specific IgE. A matching group of patients with AC seen at the allergist office during the same period underwent skin prick tests (SPTs). RESULTS: Forty-four patients were enrolled for blood work by their ophthalmologists. Seasonal and perennial forms were almost equivalent. In total, 56.8% had positive specific IgE, with higher prevalence in patients with seasonal AC (p = 0.002), other associated allergies particularly allergic rhinitis (p = 0.002) or a family history of allergy (p = 0.005). Ocular surface severity scales were not shown as predictors. High levels of total IgE were commonly detected in those with positive specific IgE. Thirty-eight patients were assessed with SPT, and all had a positive result for at least one allergen. Dust mites were found to be the most frequent allergens based upon both specific IgE (72%) and SPT (92%), followed by Parietaria and other pollens. CONCLUSION: In our study, dust mites mono- or co-sensitization is present in the majority of patients with AC, with odds of positivity being higher using SPT than specific IgE. The latter are found more readily in seasonal AC and in the presence of personal and family history of allergy.

[Screening of diabetic retinopathy and maculopathy in Lebanese population using retinography and SD-OCT: The role of telemedicine]. / DÉPISTAGE de la RÉTINOPATHE et de la MACULOPATHIE DIABÉTIQUE au LIBAN par RÉTINOGRAPHIE et par SD-OCT: INTÉRÊT de la TÉLÉMÉDECINE.

PURPOSE: Diabetes and diabetic retinopathy (DR) are nowadays a major public health threat. The aim of this study is the screening of DR and diabetic maculopathy (DM) in a primary medical care center in Lebanon. We study also the interest of retinography and of SD-OCT in a telemedicine screening program. METHODS: This is a transversal study of patients with type 2 diabetes and with a regular follow-up in a primary medical care center in Beirut. For every patient, a retinography and an SD-OCT of the macula were obtained. Photos were sent by Internet to the Ophthalmology Department of Hôtel-Dieu de France to be evaluated by a retina specialist. Visual acuity and DR risk factors were assessed. RESULTS: 119 patients were included in this study. Mean age was 51.7 ± 10.2 years (54 females and 65 males). Mean diabetes duration was 12.15 years (SD 6:2). Mean of last three measurements of glycated hemoglobin was 8.1 ± 1.34%. Diabetic retinopathy was detected in 36 patients by retinography (30.3%). Diabetic maculopathy was confirmed by SD-OCT in 13 patients. Visual acuity was significantly correlated with central macular thickness. Mean diabetes duration, mean of last three measurements of glycated hemoglobin, peripheral neuropathy, positive macroalbuminuria and treatment with insulin were independently associated to diabetic retinopathy. CONCLUSION: Teleophthalmology is an efficient way for screening diabetic retinopathy in the Lebanese population. National screening program should be undertaken to adapt teleophthalmology on a larger scale.

Effect of hemodialysis on visual acuity, intraocular pressure, and macular thickness in patients with chronic kidney disease.

BACKGROUND: The aim of this study was to evaluate the effects of hemodialysis (HD) on visual acuity, intraocular pressure (IOP), and central foveal thickness (CFT) in patients with chronic kidney disease. MATERIALS AND METHODS: Forty-nine eyes from 49 chronic kidney-disease patients were analyzed. Causes of chronic kidney disease included diabetes mellitus (n=9 patients), hypertensive nephrosclerosis (n=15 patients), and other causes (n=25 patients). All patients underwent HD in the Dialysis Unit of Hôtel-Dieu de France Hospital. Best-corrected visual acuity, CFT, and IOP were evaluated before and after HD. CFT was measured with spectral domain optical coherence tomography, and IOP was measured with Goldmann applanation tonometry. RESULTS: Neither decimal best-corrected visual acuity (pre-HD 0.71±0.32, post-HD 0.72±0.31; P=0.877) nor CFT (pre-HD 251.39±39.29, post-HD 253.09±39.26; P=0.272) significantly changed after HD. However, mean IOP significantly decreased from 13.99±2.48 before HD to 12.65±2.41 mmHg after HD (P=0.001). IOP change was significantly correlated with serum albumin levels (P=0.008) and weight changes (P=0.047). CONCLUSION: HD can affect various ocular parameters. This is particularly true of IOP, which decreases significantly following HD.

Novel 'heavy' dyes for retinal membrane staining during macular surgery: multicenter clinical assessment.

PURPOSE: To evaluate the feasibility of two novel 'heavy' dye solutions for staining the internal limiting membrane (ILM) and epiretinal membranes (ERMs), without the need for a prior fluid-air exchange, during macular surgery. METHODS: In this prospective nonrandomized multicenter cohort study, the high molecular weight dyes ILM-Blue™ [0.025% brilliant blue G, 4% polyethylene glycol (PEG)] and MembraneBlue-Dual™ (0.15% trypan blue, 0.025% brilliant blue G, 4% PEG) were randomly used in vitrectomy surgeries for macular disease in 127 eyes of 127 patients. Dye enhanced membrane visualization of the ILM and ERMs, 'ease of membrane peeling', visually detectable perioperative retinal damage, postoperative best-corrected visual acuity (BCVA), dye remnants and other unexpected clinical events were documented by 21 surgeons. RESULTS: All surgeries were uneventful, and a clear bluish staining, facilitating the identification, delineation and removal of the ILM and ERMs, was reported in all but five cases. None of the surgeries required a fluid-air exchange to assist the dye application. BCVA at 1 month after surgery improved in 83% of the eyes in the MembraneBlue-Dual™ group and in 88% in the ILM-Blue™ group. No dye remnants were detected by ophthalmoscopy, and no retinal adverse effects related to the surgery or use of the dyes were observed. CONCLUSION: The 'heavy' dye solutions ILM-Blue™ and MembraneBlue-Dual™ can be injected into a fluid-filled vitreous cavity and may facilitate staining and removal of the ILM and/or ERMs in macular surgery without an additional fluid-air exchange.

Azithromycin 1.5% ophthalmic solution: efficacy and treatment modalities in chronic blepharitis.

PURPOSE: To assess the efficacy of topical 1.5% azithromycin in the treatment of moderate to severe chronic blepharitis and to compare the efficacy of two different treatment modalities. METHODS: A randomized clinical trial included 67 patients with chronic anterior and/or posterior blepharitis, followed-up for 3 months. Signs and symptoms were graded according to severity. Patients were randomized into two groups: 33 patients in group I and 34 patients in group II. Group I patients were treated with topical 1.5% azithromycin twice a day for three days, and Group II patients were treated with topical 1.5% azithromycin twice a day for three days then at bedtime for the rest of the month. All patients were instructed to apply warm compresses and an eye-friendly soap twice daily. RESULTS: Patients in both groups tolerated the treatment with minimal irritation. A significant improvement in signs and symptoms was noted at the one week follow-up visit. Group II showed a more pronounced and longer-lasting improvement that persisted after three months of follow-up. CONCLUSION: Topical 1.5% azithromycin ophthalmic solution is an effective treatment option for chronic blepharitis. In moderate to severe blepharitis, a one month treatment is safe and shows better improvement than the three-day protocol with no significant relapse until three months of follow-up.

Azithromycin 1.5% ophthalmic solution: efficacy and treatment modalities in chronic blepharitis / Solução oftálmica de azitromicina 1,5%: eficácia e modalidades de tratamento em blefarite crônica

PURPOSE: To assess the efficacy of topical 1.5% azithromycin in the treatment of moderate to severe chronic blepharitis and to compare the efficacy of two different treatment modalities. METHODS: A randomized clinical trial included 67 patients with chronic anterior and/or posterior blepharitis, followed-up for 3 months. Signs and symptoms were graded according to severity. Patients were randomized into two groups: 33 patients in group I and 34 patients in group II. Group I patients were treated with topical 1.5% azithromycin twice a day for three days, and Group II patients were treated with topical 1.5% azithromycin twice a day for three days then at bedtime for the rest of the month. All patients were instructed to apply warm compresses and an eye-friendly soap twice daily. RESULTS: Patients in both groups tolerated the treatment with minimal irritation. A significant improvement in signs and symptoms was noted at the one week follow-up visit. Group II showed a more pronounced and longer-lasting improvement that persisted after three months of follow-up. CONCLUSION: Topical 1.5% azithromycin ophthalmic solution is an effective treatment option for chronic blepharitis. In moderate to severe blepharitis, a one month treatment is safe and shows better improvement than the three-day protocol with no significant relapse until three months of follow-up.

OBJETIVO: Avaliar a eficácia do uso tópico de azitromicina 1,5% no tratamento de blefarite crônica moderada a grave, comparando a eficácia de duas diferentes modalidades de tratamento. MÉTODOS: Um ensaio clínico randomizado incluiu 67 pacientes com blefarite anterior e/ou posterior crônica, acompanhados por três meses. Os sinais e sintomas foram classificados de acordo com a gravidade. Os pacientes foram randomizados em dois grupos: 33 pacientes no grupo I e 34 pacientes no grupo II. Os pacientes do grupo I foram tratados com azitromicina tópica 1,5% duas vezes ao dia durante três dias, e os pacientes do grupo II foram tratados com azitromicina tópica 1,5% duas vezes ao dia durante três dias e, em seguida, ao deitar, durante o resto do mês. Todos os pacientes foram instruídos a aplicarem compressas quentes e higiene palpebral duas vezes ao dia. RESULTADOS: Os pacientes em ambos os grupos toleraram o tratamento com irritação mínima. Melhora significativa dos sinais e sintomas foi observada na visita de uma semana de acompanhamento. Grupo II mostrou uma melhora mais acentuada e mais duradoura que persistiu após três meses de acompanhamento. CONCLUSÕES: A solução de azitromicina oftálmica tópica 1,5% é uma opção eficaz de tratamento para a blefarite crônica. Em blefarite moderada a grave, o tratamento de um mês é seguro e demonstrou melhora acentuada em relação ao protocolo de três dias, sem recidiva significante até três meses de acompanhamento.

Clinical and molecular findings in three Lebanese families with Bietti crystalline dystrophy: report on a novel mutation.

PURPOSE: Bietti crystalline dystrophy (BCD) is a rare autosomal recessive disorder caused by mutation of the cytochrome P450, family 4, subfamily V, polypeptide 2 (CYP4V2) gene and characterized by retinal pigmentary abnormalities and scattered deposits of crystals in the retina and the marginal cornea. The aim of this study was to investigate the spectrum of mutations in CYP4V2 in Lebanese families, and to characterize the phenotype of patients affected with BCD. METHODS: Nine patients from three unrelated Lebanese families were clinically and molecularly investigated. Detailed characterization of the patients' phenotype was performed with comprehensive ophthalmic examination, color vision study, fundus photography, visual field testing, retinal fluorescein angiography, electroretinography, and electrooculography. One family was followed for 12 years. The 11 exons of the CYP4V2 gene were sequenced. RESULTS: Symptoms consisting of night blindness, loss of paracentral visual field, and disturbed color vision were apparent during the third decade of life. Ophthalmoscopy revealed posterior pole crystalline deposits and areas of retinal pigment epithelium atrophy. Fluorescein angiography disclosed geographic areas of the pigment epithelium layer and choriocapillaris atrophy in the posterior pole and fundus periphery. The most striking findings were those of normal electroretinographic responses in some patients and clinical heterogeneity. Two mutations in CYP4V2 were found: p.I111T (c.332T>C) in exon 3 in two families and the novel p.V458M (c.1372G>A) mutation in exon 9 in one family. CONCLUSIONS: These patients are affected with Bietti crystalline dystrophy without corneal involvement. Variation in disease severity and electroretinographic responses suggests that environmental or additional genetic factors influence the course of the retinal disease. The CYP4V2 p.I111T (c.332T>C) mutant allele may be especially prevalent among patients with BCD in Lebanon, resulting from a single founder.

Xanthophylls and eye health of infants and adults.

Lutein and zeaxanthin are the only carotenoids present in the eye. They cannot be synthesized de novo and are specifically concentrated in the macula. They appear to have at least two major functions: to filter out blue light and thus prevent ensuing damages to the eye and to act as antioxidants. Infants are particularly at risk from both blue light and oxidative damage to eye tissues. Lutein is present in human milk but is not currently added to infant formulas. Fortifying formulae with lutein in order to match more closely human milk might help protect the infant's sensitive eyes. In adults, the exact pathogenesis of age-related maculopathy remains unknown. Light damage, inflammation, and the disruption of cellular processes by oxidative stress may play an important role in the degenerative process. Manipulation of intake of xanthophylls has been shown to augment macular pigment, therefore it is thought that carotenoid dietary supplements could prevent, delay, or modify the course of age-related maculopathy. However, definite evidence of the effect of carotenoids, the optimal doses to use, and the supplementation duration are still under investigation.

Evaluation of the new photosensitizer Stakel (WST-11) for photodynamic choroidal vessel occlusion in rabbit and rat eyes.

PURPOSE: To evaluate the photodynamic potential of a new hydrosoluble photosensitizer (WST-11, Stakel; Steba Biotech, Toussus-Le-Noble, France), for use in occlusion of normal choroidal vessels in the rabbit eye and CNV (choroidal neovascularization) in the rat eye. METHODS: Occlusive and nonocclusive parameters of Stakel and verteporfin photodynamic therapy (PDT) were investigated in pigmented rabbits. Eyes were followed by fluorescein angiography (FA) and histology at various intervals after PDT. RESULTS: When occlusive parameters (fluence of 50 J/cm(2), 5 mg/kg drug dose and DLI [distance to light illumination] of 1 minute) were used, Stakel PDT was efficient immediately after treatment without associated structural damage of the RPE and retina overlying the treated choroid in the rabbit eye. Two days later, total occlusion of the choriocapillaries was seen in 100% of the treated eyes, along with accompanying histologic structural changes in the overlying retina. When the occlusive parameters (fluence, 100 J/cm2; drug dose, 12 mg/m2; and DLI, 5 minutes) of verteporfin PDT were used, occlusion of the choriocapillaries was observed in 89% of the treated eyes. Histology performed immediately after treatment demonstrated structural damage of the overlying retina and RPE layer. Weaker, nonocclusive Stakel PDT parameters (25 J/cm2, 5 mg/kg, and DLI of 10 minutes) did not induce choriocapillary occlusion or retinal lesions on FA or histology. Weaker, nonocclusive verteporfin PDT parameters (10 J/cm2, 0.2 mg/kg, and DLI of 5 minutes) did not induce choriocapillary occlusion. However, histology of these eyes showed the presence of damage in the retinal and choroidal tissues. Moreover, preliminary results indicate that selective CNV occlusion can be achieved with Stakel PDT in the rat eye. CONCLUSIONS: Unlike verteporfin PDT, Stakel PDT does not cause direct damage to the RPE cell layer or retina. These observations indicate that Stakel PDT may have a high potential for beneficial therapeutic outcomes in treatment of AMD.

Electrically assisted ocular gene therapy.

Electrotransfer and iontophoresis are being developed as innovative non-viral gene delivery systems for the treatment of eye diseases. These two techniques rely on the use of electric current to allow for higher transfection yield of various ocular cell types in vivo. Short pulses of relatively high-intensity electric fields are used for electrotransfer delivery, whereas the iontophoresis technique is based on the application of low voltage electric current. The basic principles of these techniques and their potential therapeutic application for diseases of the anterior and posterior segments of the eye are reviewed. Iontophoresis has been found most efficient for the delivery of small nucleic acid fragments such as antisense oligonucleotides, siRNA, or ribozymes. Electrotransfer, on the other hand, is being developed for the delivery of oligonucleotides or custom designed plasmids. The wide range of strategies already validated and the potential for targeting specific types of cells confirm the promising early observations made using electrotransfer and iontophoresis. These two nonviral delivery systems are safe and can be used efficiently for targeted gene delivery to ocular tissues in vivo. At the present, their application for the treatment of ocular human diseases is nearing its final stages of adaptation and practical implementation at the bedside.

Ultrasound biomicroscopy study of the Verisyse aphakic intraocular lens combined with penetrating keratoplasty in pseudophakic bullous keratopathy.

PURPOSE: To evaluate anterior segment modifications after penetrating keratoplasty (PKP), previous anterior chamber intraocular lens (IOL) removal, and Verisyse IOL (AMO) implantation over the iris or under the iris for the treatment of pseudophakic bullous keratopathy (PBK) using ultrasound biomicroscopy. SETTING: Department of Ophthalmology, Poitiers University Hospital, Poitiers, France. METHODS: A prospective randomized comparative case series included 27 patients (27 eyes) with PBK who had PKP and implantation of a Verisyse VRSA54 aphakic IOL. The IOL was implanted over the iris in 13 patients (Group A) and under the iris in a reversed position in 14 patients (Group B). Ultrasound biomicroscopy scans 6 months after surgery measured central anterior chamber depth (ACD), iris thickness (IT), distance of the haptics from the corneal endothelium (CED), distance of the haptics from the ciliary body (CBD), angle opening distance (AOD) 500 mum from the scleral spur (AOD500) and the iridocorneal angle theta on the 4 o'clock meridian lines (AOD3; AOD9; AOD12; AOD6/theta12, theta6, theta3, theta9). RESULTS: No significant difference was found in IT, CBD, or AOD12 between Group A and Group B (P >.05). In Group B, the mean ACD was deeper by approximately 55% (P = .008); CED3 was larger by 69% (P = .0162), CED9 by 80% (P = .0128), AOD3 by 57% (P = .0309), AOD9 by 140% (P = .0057), and AOD6 by 44% (P = .0399); and theta3 was wider by 52% (P = .046), theta9 by 123% (P = .0068), theta12 by 50% (P = .0492), and theta6 by 81% (P = .0237). CONCLUSION: Ultrasound biomicroscopy showed that in eyes that had PKP with Verisyse IOL enclavation to the posterior plane of the iris, which involved posterior translation of the iridal plane, the ACD was significantly deeper and the CED and AOD were significantly larger than in eyes with anterior enclavation of the IOL.

Amniotic membrane transplantation in severe bacterial keratitis.

PURPOSE: To determine whether a combination of early amniotic membrane transplantation (AMT) and early topical corticosteroid treatment could be a safe adjuvant therapy during antibacterial treatment in severe bacterial keratitis (BK) for relieving pain, avoiding iatrogenic epithelial toxicity, and allowing earlier use of topical steroids. METHODS: In a prospective noncomparative case series, 12 patients with severe microscopically-proven BK were treated with immediate maximal topical antibiotics followed by AMT at 48 hours (single-layer epithelial side-down or multilayer epithelial side-up), plus topical steroid treatment at 72 hours. Pain relief (NRS-11 numeric rating pain scale) and the corneal epithelium healing were measured. RESULTS: The follow-up rate was 7.5 person-months, with AMT performed once in 2 patients and twice in 10 patients with BK caused by Pseudomonas aeruginosa (5), Klebsiella pneumoniae (1), Moraxella cattharalis (1), Staphylococcus aureus (1), Staphylococcus epidermidis (2), or Streptococcus pneumoniae (1). A significant decrease in the pain score was noted from the admission day (median, 8; range, 7-10) to shortly after AMT (at day 3: median, 2; range, 1-3). Epithelial healing was achieved between 8 and 45 days (mean, 25.5 +/- 9.7 days). Neither perforation nor neovascularization was observed. CONCLUSIONS: Early AMT combined with topical corticosteroid in severe BK provides immediate pain relief and allows epithelial healing.

Ocular gene therapy: a review of nonviral strategies.

Along with viral vectors, non-viral strategies have been developed in order to efficiently deliver nucleic acids to ocular cells. During the last decade, we have observed that the outcome of these non-viral delivery systems depends on the genetic material used, the targeted tissue or cells, the expected effect duration, and the routes of administration. Assessment of efficiency has been evaluated in normal eyes or in animal models of ocular diseases. The chemical and physical methods that have been adapted for the delivery of nucleic acids to ocular tissues are highlighted and discussed in this review. Also, the results obtained with different non-viral strategies from their initial conception to their present development are summarized. At the present, selective targeting of ocular tissues and cells can be achieved using the most yielding route of administration to the eye in combination with an appropriate drug delivery technique.

Oligonucleotide-polyethylenimine complexes targeting retinal cells: structural analysis and application to anti-TGFbeta-2 therapy.

PURPOSE: The aim of this study was to characterize oligonucleotide-polyethylenimine (ODN/PEI) complex preparation for potential transfection of retinal cells in vitro and in vivo. METHODS: The effect of medium preparation [HEPES-buffered saline (HBS), water] on particle size and morphology was evaluated. Cultured Lewis rat retinal Müller glial (RMG) cells were transfected using fluorescein isothiocyanate (FITC)-ODN/PEI complexes specifically directed at transforming growth factor beta (TGFbeta)-2. Efficacy of transfection was evaluated using confocal microscopy, and regulation of gene expression was assayed using quantitative real-time RT-PCR and ELISA assay. One, 24, and 72 h after injection of FITC-ODN/PEI complexes into the vitreous of rat eyes, their distribution was analyzed on eye sections. RESULTS: Complexes prepared in HBS were smaller than complexes prepared in pure water and presented a core-shell structure. These particles showed a high cellular internalization efficacy, along with a significant and specific down-regulation of TGFbeta-2 expression and production in RMG cells, correlating with specific inhibition of cell growth at 72 h. In vivo, complexes efficiently transfect retinal cells and follow a transretinal migration at 24 h. After 72 h, ODN seems to preferentially target RMG cells without inducing any detectable toxicity. CONCLUSIONS: Specific down-regulation of TGFbeta-2 expression using ODN/PEI complexes may have potential interest for the treatment of retinal diseases associated with glial proliferation.

Nanoparticles for gene delivery to retinal pigment epithelial cells.

PURPOSE: To evaluate the safety and potential use of poly(lactic) acid (PLA) and poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) as vectors for gene transfer to RPE cells. METHODS: Experiments were conducted with primary bovine RPE cells and with the ARPE-19 human RPE cell line. Rhodamine loaded NPs were used to study factors influencing the internalization process by the various RPE cells: concentrations of NPs, duration of contact time, stage of cell culture and ambient temperature. The extent of NPs internalization was evaluated by fluorescence and phase microscopy. Potential NP toxicity was measured by the trypan blue exclusion dye test and the MTT method. Green fluorescent protein (GFP) plasmid or red nuclear fluorescent protein (RNFP) plasmid were sequestered in NPs. The ability ot these "loaded" NPs to generate gene transfection and protein expression in RPE cells was assessed both in vivo and in vitro by fluorescence and confocal microscopy. RESULTS: The extent of NP internalization in cultured cells increases with their concentration reaching a plateau at 1 mg/ml and a contact time of up to 6 h. Temperature and culture stage did not influence the in vitro internalization process. No toxic effects on RPE cells could be detected when these were incubated with up to 4 mg/ml of NPs. In human and bovine RPE cells incubated with GFP loaded NPs, cytoplasmic green fluorescence was observed in 14+/-1.65% of the cultured cells. Incubation with RNFP loaded NPs yielded a nuclear red fluorescence in 18.9+/-1.6% of the cells. These percentage levels of expression initially detected after 48 h of incubation remained unchanged during the following 8 additional days in culture. No significant differences in the extent of cytoplasm or nuclear fluorescence expression were observed between bovine or human RPE cultured cells. In vivo, a preferential RNFP expression within the RPE cell layer was detected after intra vitreous injection of RNFP plasmid loaded NPs. CONCLUSIONS: The ability of PLGA NPs to sequester plasmids, their nontoxic characteristics, and rapid internalization enables gene transfer and expression in RPE cells. These findings may be of potential use when designing future gene therapy strategies for ocular diseases of the posterior segment.

Ocular biocompatibility of a poly(ortho ester) characterized by autocatalyzed degradation.

The biocompatibility of autocatalyzed poly(ortho ester) (POE(70)LA(30)), a viscous, hydrophobic, bioerodible polymer, was investigated. POE(70)LA(30) was synthesized, sterilized by gamma irradiation, and injected in rabbit eyes at adequate volumes through subconjunctival, intracameral, intravitreal, and suprachoroidal routes. Clinical examinations were performed postoperatively at regular time points for 6 mo, and histopathologic analysis was carried out to confirm tissular biocompatibility. After subconjunctival injection, the polymer was well tolerated and persisted in the subconjunctival space for about 5 weeks. In the case of intracameral injections, polymer biocompatibility was good; the POE(70)LA(30) bubble was still present in the anterior chamber for up to 6 mo after injection. No major histopathologic anomalies were detected, with the exception of a localized Descemet membrane thickening. After intravitreal administration, POE(70)LA(30) biocompatibility was excellent, and no inflammatory reaction could be detected during the observation period. The polymer was degraded in approximately 3 mo. Suprachoroidal injections of POE(70)LA(30) were reproducible and well tolerated. POE(70)LA(30) triggered a slight elevation of the retina and choroid upon clinical observation. The polymer was detectable in the suprachoroidal space for about 6 mo. No inflammatory reaction and no major retinal anomalies could be detected by histology. In conclusion, POE(70)LA(30) appears to be a promising biomaterial for intraocular application, potentially providing sustained drug delivery over an extended period of time, with a good tolerance.

Ocular drug delivery targeting the retina and retinal pigment epithelium using polylactide nanoparticles.

PURPOSE: To study the kinetics of polylactide (PLA) nanoparticle (NP) localization within the intraocular tissues and to evaluate their potential to release encapsulated material. METHODS: A single intravitreous injection (5 micro L) of an NP suspension (2.2 mg/mL) encapsulating either Rh-6G (Rh) or Nile red (Nr) was performed. Animals were killed at various times, and the NPs localization within the intraocular tissues was studied by environmental scanning electron microscopy (ESEM), confocal microscopy, light microscopy histology, fluorescence microscopy, and immunohistochemistry. Eyes injected with blank NPs, free Rh, or PBS solution were used as the control. RESULTS: ESEM showed the flow of the NPs from the site of injection into the vitreous cavity and their rapid settling on the internal limiting membrane. Histology demonstrated the anatomic integrity of the injected eyes and showed no toxic effects. A mild inflammatory cell infiltrate was observed in the ciliary body 6 hours after the injection and in the posterior vitreous and retina at 18 to 24 hours. The intensity of inflammation decreased markedly by 48 hours. Confocal and fluorescence microscopy and immunohistochemistry showed that a transretinal movement of the NPs was gradually taking place with a later localization in the RPE cells. Rh encapsulated within the injected NPs diffused and stained the retina and RPE cells. PLA NPs were still present within the RPE cells 4 months after a single intravitreous injection. CONCLUSIONS: Intravitreous injection of PLA NPs appears to result in transretinal movement, with a preferential localization in the RPE cells. Encapsulated Rh diffuses from the NPs and stains the neuroretina and the RPE cells. The findings support the idea that specific targeting of these tissues is feasible. Furthermore, the presence of the NPs within the RPE cells 4 months after a single injection shows that a steady and continuous delivery of drugs can be achieved.

Phototherapeutic keratectomy for BIGH3-linked corneal dystrophy recurring after penetrating keratoplasty.

PURPOSE: To determine visual results and report side effects and complications after phototherapeutic keratectomy (PTK) for BIGH3-linked corneal dystrophy recurring after penetrating keratoplasty. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Forty-two excimer laser PTK procedures were performed in 42 eyes of 29 patients with BIGH3-linked corneal dystrophies. Genetic status of all patients was determined and allowed us to assess an unambiguous diagnosis. Preoperative diagnoses included LCDIIIA/A546T (1 eye), R124 l+DT125-DE126 (4 eyes), GICD/R555W (14 eyes), LCDI/R124C (6 eyes), SGD/R124 l (16 eyes), and CDBII/R555Q (1 eye). INTERVENTION: Two excimer lasers (Summit Excimed UV 200, Summit Technology, Waltham, MA and Nidek EC 5000, Nidek, Inc., Gamagori, Japan) were used to perform all PTKs. Indications for performing PTK after a graft were severe decrease of the best-corrected visual acuity (BCVA) related to recurrent corneal deposits and/or painful recurrent epithelial erosions. MAIN OUTCOME MEASURES: Preoperative and postoperative BCVA were analyzed, significant recurrences after treatment were noted, and postoperative complications were recorded. RESULTS: Mean preoperative BCVA was 0.2 +/- 0.12 in the decimal chart, mean postoperative BCVA was 0.52 +/- 0.16 with a mean follow-up of 3.13 +/- 1.77 years (range, 0.3-6.65 years). Visual acuity was significantly improved after surgery (P < 0.05). The magnitude of the change in visual acuity was dependent on the mutation (P < 0.001). Seven symptomatic recurrences were observed. One regressive graft rejection and 4 cases of severe postoperative haze were observed. No other complications were noted. CONCLUSIONS: PTK is a simple, safe, and efficient technique for the treatment of recurrent corneal dystrophies; in many cases it prevents or delays the major incumbent problems of repeated grafting.

Cryoextraction of episcleral Miragel buckle elements: a new technique to reduce fragmentation.

A step-by-step description of a surgical technique for episcleral Miragel buckle removal is reported. After dissection of the conjunctiva and the capsule surrounding the Miragel element, the extremity of the buckle is pulled out with a cryoprobe. The removal of Miragel episcleral buckle with the cryoprobe is a safe and effective technique with a low fragmentation rate and a reduction of the surgical risk related to the use of sharp forceps near a possibly weakened sclera. Procedure time seems also to be reduced.