Effect of Factor XIII-A G185T Polymorphism on Visual Prognosis after Photodynamic Therapy for Neovascular Macular Degeneration.

Macular degenerations represent leading causes of central blindness or low vision in developed countries. Most of these severe visual disabilities are due to age-related macular degeneration (AMD) and pathologic myopia (PM), both of which are frequently complicated by subfoveal choroidal neovascularization (CNV). Photodynamic therapy with verteporfin (PDT-V) is still employed for CNV treatment in selected cases or in combined regimen. In Caucasian patients, the common polymorphism G185T of factor XIII-A gene (FXIII-A-G185T; rs5985) has been described as predictor of poor angiographic CNV responsiveness to PDT-V. Nevertheless, the prognostic implications of this pharmacogenetic determinant on long-term visual outcome after a PDT-V regimen have not been evaluated. We retrospectively selected Caucasian patients presenting with treatment-naive CNV and receiving standardized PDT-V protocol for two years. The study population included patients affected by subfoveal CNV secondary to AMD or PM. We assessed the correlations between the polymorphic allele T of FXIII-A-G185T and: (1) total number of photodynamic treatments; and (2) change in visual acuity from baseline to the end of the follow-up period. Considering a total study population of 412 patients with neovascular AMD or PM, the carriers of 185 T-allele of FXIII-A (GT or TT genotype) received a higher number of photodynamic treatments than patients without it (GG wild-type genotype) (p < 0.01; mean number of PDT-V: 5.51 vs. 3.76, respectively). Moreover, patients with 185 T-allele of FXIII-A had a more marked worsening of visual acuity at 24 months than those with the GG-185 wild genotype (p < 0.01; mean difference in logMAR visual acuity: 0.22 vs. 0.08, respectively). The present findings show that the G185T polymorphism of the FXIII-A gene is associated with significant differences in the long-term therapeutic outcomes of patients treated with standardized PDT-V protocol. The comprehensive appraisal of both anti-thrombophilic effects due to FXIII-A G185T variant and photo-thrombotic action of PDT-V toward CNV provides several clues about the rationale of this intriguing pharmacogenetic correlation. Further investigations are warranted to outline the appropriate paradigm for guiding PDT-V utilization in the course of the combined therapeutic protocol for neovascular macular degeneration.

Does Insulin Like Growth Factor-1 (IGF-1) Deficiency Have a "Protective" Role in the Development of Diabetic Retinopathy in Thalassamia Major Patients?

RATIONALE: Both insulin and IGF-1 have been implicated in the control of retinal endothelial cell growth, neovascularization and diabetic retinopathy. Recent findings have established an essential role for IGF-1 in angiogenesis and demonstrated a new target for control of retinopathy that explains why diabetic retinopathy initially increases with the onset of insulin treatment. OBJECTIVE: This cross-sectional study was designed to give insights into relationship between Insulin-Growth-Factor 1 (IGF-1) levels and diabetic retinopathy (DR) in a sample of thalassemia major (TM) patients with insulin dependent diabetes mellitus (IDDM). This relation was not previously evaluated, despite the fact that both diseases co-exist in the same patient. The study also describes the clinical and biochemical profile of the associated complications in TM patients with and without IDDM. DESIGN: A population-based cross-sectional study. PARTICIPANTS: The study includes 19 consecutive TM patients with IDDM and 31 age- and sex-matched TM patients without IDDM who visited our out-patient clinics for an endocrine assessment. METHODS: An extensive medical history, with data on associated complications and current medications, was obtained. Blood samples were drawn in the morning after an overnight fast to measure the serum concentrations of IGF-1, glucose, fructosamine, free thyroxine (FT4), thyrotropin (TSH) and biochemical analysis. Serologic screening assays for hepatitis C virus seropositivity (HCVab and HCV-RNA) were also evaluated; applying routine laboratory methods. Plasma total IGF-1 was measured by a chemiluminescent immunometric assay (CLIA) method. Ophthalmology evaluation was done by the same researcher using stereoscopic fundus biomicroscopy through dilated pupils. DR was graded using the scale developed by the Global Diabetic Retinopathy Group. Iron stores were assessed by direct and indirect methods. RESULTS: Eighteen TM patients with IDDM (94.7 %) and ten non-diabetic patients (32.2 %) had IGF-1 levels below the 2.5(th) percentile of the normal values for the Italian population. The mean serum IGF-1 concentrations were significantly lower in the diabetic versus the non-diabetic TM groups (p < 0.001). DR was present in 4 (21 %) of 19 TM patients with IDDM and was associated with the main classical risk factors, namely inefficient glycemic control and duration of the disease but not hypertension. Using the scale developed by the Global Diabetic Retinopathy Group, the DR in our patients was classified as non proliferative diabetic retinopathy (NPDR). Only a few numbers of microaneurysms [1-3] were detected. Our data also confirm the strong association of IDDM in TM patients with other endocrine and non-endocrine complications.

Mechanism of inflammation in age-related macular degeneration: an up-to-date on genetic landmarks.

Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment among people over 50 years of age, accounting for up to 50% of all cases of legal blindness in Western countries. Although the aging represents the main determinant of AMD, it must be considered a multifaceted disease caused by interactions among environmental risk factors and genetic backgrounds. Mounting evidence and/or arguments document the crucial role of inflammation and immune-mediated processes in the pathogenesis of AMD. Proinflammatory effects secondary to chronic inflammation (e.g., alternative complement activation) and heterogeneous types of oxidative stress (e.g., impaired cholesterol homeostasis) can result in degenerative damages at the level of crucial macular structures, that is photoreceptors, retinal pigment epithelium, and Bruch's membrane. In the most recent years, the association of AMD with genes, directly or indirectly, involved in immunoinflammatory pathways is increasingly becoming an essential core for AMD knowledge. Starting from the key basic-research notions detectable at the root of AMD pathogenesis, the present up-to-date paper reviews the best-known and/or the most attractive genetic findings linked to the mechanisms of inflammation of this complex disease.

Mechanism of inflammation in age-related macular degeneration.

Age-related macular degeneration (AMD) is a multifactorial disease that represents the most common cause of irreversible visual impairment among people over the age of 50 in Europe, the United States, and Australia, accounting for up to 50% of all cases of central blindness. Risk factors of AMD are heterogeneous, mainly including increasing age and different genetic predispositions, together with several environmental/epigenetic factors, that is, cigarette smoking, dietary habits, and phototoxic exposure. In the aging retina, free radicals and oxidized lipoproteins are considered to be major causes of tissue stress resulting in local triggers for parainflammation, a chronic status which contributes to initiation and/or progression of many human neurodegenerative diseases such as AMD. Experimental and clinical evidences strongly indicate the pathogenetic role of immunologic processes in AMD occurrence, consisting of production of inflammatory related molecules, recruitment of macrophages, complement activation, microglial activation and accumulation within those structures that compose an essential area of the retina known as macula lutea. This paper reviews some attractive aspects of the literature about the mechanisms of inflammation in AMD, especially focusing on those findings or arguments more directly translatable to improve the clinical management of patients with AMD and to prevent the severe vision loss caused by this disease.

Genetic predictors of response to photodynamictherapy.

In Western countries, therapeutic management of patients affected by choroidal neovascularization (CNV) secondary to different typologies of macular degeneration represents a major health care problem. Age-related macular degeneration is the disease most frequently associated with CNV development. Schematically, CNVs can be distinguished into classic and occult subtypes, which are characterized by variable natural history and different responsiveness to some therapeutic procedures. At present, the dramatic vision loss due to CNV can be mainly treated by two interventional strategies, which are utilizable in either single or combined modalities: photodynamic therapy with verteporfin (PDT-V), and intravitreal administration of drugs acting against vascular endothelial growth factor. The combined use of PDT-V and anti-angiogenic drugs represents one of the most promising strategies against neovascular macular degeneration, but it unavoidably results in an expensive increase in health resource utilization. However, the positive data from several studies serve as a basis for reconsidering the role of PDT-V, which has undergone a renaissance prompted by the need for a more rational therapeutic approach toward CNV. New pharmacogenetic knowledge of PDT-V points to exploratory prospects to optimize the clinical application of this intriguing photothrombotic procedure. In fact, a Medline search provides data regarding the role of several single nucleotide polymorphisms (SNPs) as genetic predictors of CNV responsiveness to PDT-V. Specifically, correlations between SNPs and different levels of PDT-V efficacy have been detected by examining the gene variants influencing (i) thrombo-coagulative pathways, i.e. methylenetetrahydrofolate reductase (MTHFR) 677C>T (rs1801133), factor V (F5) 1691G>A (rs6025), prothrombin (F2) 20210G>A (rs1799963), and factor XIII-A (F13A1) 185G>T (rs5985); (ii) complement activation and/or inflammatory processes, i.e. complement factor H (CFH) 1277T>C (rs1061170), high-temperature requirement factor A1 (HTRA1) promoter -512G>A (rs11200638), and two variants of the C-reactive protein (CRP) gene (rs2808635 and rs876538); and (iii) production and bioavailability of vascular endothelial growth factor (VEGFA -2578C>A [rs699947] and rs2146323). This article critically evaluates both the clinical plausibility and the opportunity to utilize the most important SNP-response interactions of PDT-V for an effective upgrade of the current anti-CNV therapeutic scenario. In addition, the pharmacogenetics of a very severe post-PDT-V adverse event, i.e. a decrease in acute vision, is briefly discussed. A comprehensive appraisal of the findings reviewed in this article should be carefully considered to design future trials aimed at verifying (after proper genotypic stratification of the enrolled patients) whether these innovative pharmacogenetic approaches will be able to improve the multifaceted interventional management of neovascular macular degeneration.

Pharmacogenetic aspects in therapeutic management of subfoveal choroidal neovascularisation: role of factor XIII-A 185 T-allele.

In Western Countries, the occurrence of choroidal neovascularization (CNV) secondary to different forms of macular degeneration represents a common cause of blindness. Particularly, age-related macular degeneration (AMD) and pathologic myopia (PM) are the most frequent diseases related to CNV development. At present, the combined employment of drugs acting against vascular endothelial growth factor (anti-VEGF) and photodynamic therapy with verteporfin (PDT-V) is a promising therapeutic strategy for neovascular macular degenerations. However, this approach inevitably leads to an increase in health-resource utilization. In several clusters of patients treated for CNV, correlations among common gene polymorphisms implicated in coagulation- or complement-cascade and different levels of, respectively, post-PDT-V or post-anti-VEGF benefit have been reported. Factor XIII-A G185T substitution (rs5985), a frequent anti-thrombophilic genetic variant of Caucasian ethnic groups, unequivocally influences a worsening of the CNV responsiveness to PDT-V in patients affected by either AMD- or PM-related CNV. These coherent pharmacogenetic findings point out the opportunities to: i. optimize the eligibility criteria of PDT-V and, ii. customize the interventional strategy against CNV, for finally minimizing the socio-economic burden of neovascular macular degenerations.

Inflammatory mediators and angiogenic factors in choroidal neovascularization: pathogenetic interactions and therapeutic implications.

Choroidal neovascularization (CNV) is a common and severe complication in heterogeneous diseases affecting the posterior segment of the eye, the most frequent being represented by age-related macular degeneration. Although the term may suggest just a vascular pathological condition, CNV is more properly definable as an aberrant tissue invasion of endothelial and inflammatory cells, in which both angiogenesis and inflammation are involved. Experimental and clinical evidences show that vascular endothelial growth factor is a key signal in promoting angiogenesis. However, many other molecules, distinctive of the inflammatory response, act as neovascular activators in CNV. These include fibroblast growth factor, transforming growth factor, tumor necrosis factor, interleukins, and complement. This paper reviews the role of inflammatory mediators and angiogenic factors in the development of CNV, proposing pathogenetic assumptions of mutual interaction. As an extension of this concept, new therapeutic approaches geared to have an effect on both the vascular and the extravascular components of CNV are discussed.

Impact of coagulation-balance gene predictors on efficacy of photodynamic therapy for choroidal neovascularization in pathologic myopia.

PURPOSE: To investigate whether different coagulation-balance genetic backgrounds might explain the variable clinical outcomes detected, after a single photodynamic therapy with verteporfin (PDT-V), in Caucasian patients with subfoveal choroidal neovascularization (CNV) secondary to pathologic myopia (PM). DESIGN: Retrospective, consecutive, nonrandomized, interventional cases series. PARTICIPANTS: Two hundred thirty-four patients exclusively treated with standardized PDT-V for the presence of PM-related classic CNV. METHODS: The enrolled patients were subdivided as responders or nonresponders based on CNV responsiveness to the first PDT-V over a 3-month period. Three common gene polymorphisms, factor XIII-A G185T, methylenetetrahydrofolate reductase C677T, and methionine synthase reductase A66G, were genotyped by polymerase chain reaction in each patient. MAIN OUTCOME MEASURES: The measures of CNV responsiveness to PDT-V were the changes, respect to baseline, of fluorescein angiography CNV leakage, greatest linear dimension, and area of the lesion. Logistic regression analyses were performed to explore the predictive role of phenotypic (patient's age, baseline visual acuity, and baseline CNV area) and genotypic (all the mentioned mutations) variables regarding PDT-V efficacy. RESULTS: Responders to PDT-V were overrepresented within carriers of methylenetetrahydrofolate reductase 677 T-allele (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.8-5.4; P = 0.001) and, to a minor extent, among patients with better visual acuity at baseline (OR, 11.8; 95% CI, 1.6-88.0; P = 0.02). However, predictors of PDT-V lack of efficacy were patient's age (OR, 0.73; 95% CI, 0.62-0.86; P = 0.01) and, especially, factor XIII-A 185 GT/TT genotypes (OR, 0.19; 95% CI, 0.11-0.35; P = 0.0001). All the other considered predictive factors did not significantly influence the CNV responsiveness to PDT-V. CONCLUSIONS: These findings document the presence of pharmacogenetic correlations between common coagulation-balance gene polymorphisms and different CNV responsiveness to PDT-V in Caucasian patients with neovascular PM.

Parnaparin versus aspirin in the treatment of retinal vein occlusion. A randomized, double blind, controlled study.

INTRODUCTION: Retinal vein occlusion (RVO) is a common cause of unilateral visual loss. Evidence based treatment recommendations for patients with RVO cannot be made because of the lack of adequate clinical trials. To compare the efficacy and safety of aspirin and of a low molecular weight heparin, parnaparin, in the treatment of RVO. MATERIALS AND METHODS: In a multicenter, randomized, double blind, controlled trial eligible patients with a delay between symptoms onset and objective diagnosis of less than 15 days were randomized to aspirin 100 mg/day for 3 months or to a fixed daily dose of parnaparin, 12.800 IU for 7 days followed by 6.400 IU for a total of 3 months. Primary end-point of the study was the incidence of functional worsening of the eye with RVO at 6 months, as assessed by fluorescein angiography, visual acuity, and visual field. Study end-points were adjudicated by an independent committee. RESULTS: Sixty-seven patients were enrolled in the study and 58 of them (28 treated with parnaparin, 30 with aspirin) were evaluable for the analysis. Baseline characteristics were well balanced between groups. Functional worsening was adjudicated in 20.7% of patients treated with parnaparin and in 59.4% of patients treated with ASA (p=0.002). Recurrent RVO was diagnosed in 3 patients, all treated with ASA (p=n.s.). Bleeding rates were similar between the two groups. CONCLUSIONS: Parnaparin appears to be more effective than aspirin in preventing functional worsening in patients with RVO. The results of this study need to be confirmed in a larger clinical trial.

Predictive role of gene polymorphisms affecting thrombin-generation pathway in variable efficacy of photodynamic therapy for neovascular age-related macular degeneration.

Age-related macular degeneration (AMD) represents the leading cause of central blindness in developed countries. The majority of severe vision loss occurs in the neovascular form of AMD, generally characterized by the presence of choroidal neovascularization (CNV) beneath the fovea. Photodynamic therapy with verteporfin (PDT-V) and drugs acting against vascular endothelial growth factor are the most commonly employed treatments for AMD-related subfoveal CNV. The combined use of both these strategies is the most promising therapeutic approach towards this harmful disease. The therapeutic action of PDT-V depends to a photochemical perturbation of thrombo-coagulative processes within CNV. Predictive correlations between peculiar coagulation-balance gene polymorphisms and different levels of post-PDT-V benefit have been recently documented in Caucasian patients with neovascular AMD. Particularly, heterozygous A-allele carriers of factor V Leiden 1691 or prothrombin 20210 gene are characterized by a greater possibility to exhibit clinical benefit after PDT-V. Both mutations induce thrombophilia increasing the thrombin generation in plasma and, thus, they can consistently intensify the photothrombotic phase of the therapeutic CNV occlusion. In prospect, considering the different individual susceptibility to PDT-V, a preoperative assessment of the genotypic thrombophilic background could optimize the eligibility criteria of this intriguing treatment. This review summarizes some of the recent published patents on treatment of neovascular AMD, with a particular attention to PDT-V application in combined therapeutic modalities.

Predictive role of C677T MTHFR polymorphism in variable efficacy of photodynamic therapy for neovascular age-related macular degeneration.

Age-related macular degeneration (AMD) complicated by subfoveal choroidal neovascularization (CNV) is the leading cause of severe central blindness in developed countries. AMD-related CNVs are distinguishable in classic and occult subtypes, characterized by variable natural history and different responsiveness to therapeutic procedures. Combined and repeated use of photodynamic therapy with verteporfin (PDT-V) and antiangiogenic drugs represents the most promising strategy against neovascular AMD, but it is unavoidably associated with mounting health-resource utilization. Predictive correlations between peculiar coagulation-balance gene variants and different levels of post-PDT-V benefit have recently been documented in Caucasians with AMD-related CNVs. In particular, methylenetetrahydrofolate reductase C677T substitution, a common thrombophilic folate pathway genotypic polymorphism, influences a better CNV responsiveness to PDT-V in classic- but not in occult-CNV cases. These pharmacogenetic findings indicate the opportunities to optimize the eligibility criteria of PDT-V and/or to perform this intriguing therapy in a customized manner, for finally minimizing the socio-economic burden of neovascular AMD.

Efficacy of probing for children with congenital nasolacrimal duct obstruction: a retrospective study using fluorescein dye disappearance test and lacrimal sac echography.

PURPOSE: To evaluate B-scan echography for the assessment of lacrimal sac (LS) in pediatric epiphora secondary to congenital nasolacrimal duct obstruction (CNLDO), and to verify its predictive role in functional efficacy of nasolacrimal duct probing. PATIENTS AND METHODS: Thirty-nine eyes of 23 consecutive children, treated with a single probing for persistent CNLDO-related epiphora, were retrospectively studied. These cases were investigated both collectively and considering two sub-groups: group A (ten patients [20 eyes] 13 months. Fluorescein dye disappearance test at 10 minutes (FDDT-10) and ultrasound examination of LS were performed before and after probing. An echographic LS scoring system (grade 0 = no LS enlargement; grade 1 = slight longitudinal LS enlargement; grade 2 = longitudinal and slight transverse LS enlargement; grade 3 = marked longitudinal and transverse LS enlargement) was introduced as a predictor of probing efficacy, estimating FDDT-10 modification between pre- and post-operative checks. RESULTS: Echographic LS evaluation was easily practicable without sedation. In the total cluster and in both age sub-groups, post-probing FDDT-10 decreased with respect to pre-probing value (p < 0.001). Post-probing LS score improved with respect to pre-probing check within the total cluster and group A (p < 0.05). Strong correlation between pre-probing LS alteration and functional probing failure was present in each studied cluster (all p values <0.0001). Within group B, a greater gain of post-probing FDDT-10 was more frequent in patients with a better pre-probing LS score, as well as in younger children (both p values <0.0001). CONCLUSIONS: In children with CNLDO-related epiphora, B-scan echography of the LS can represent a reliable and useful examination for a better understanding of the functional prognosis after probing treatment.

Topical and oral ketorolac administration increases the intraocular pressure-lowering effect of latanoprost.

PURPOSE: To verify the influence of a non-steroidal anti-inflammatory drug (NSAID), ketorolac (topical and oral) on the intraocular pressure reduction induced by 0.005% latanoprost topical administration, both in patients affected by primary open-angle glaucoma and in healthy controls. METHODS: Two groups of subjects were enrolled for this randomized, prospective, masked clinical study: 16 glaucomatous patients well controlled with 0.005% latanoprost eyedrops (group I) and 16 healthy adult volunteers (group II). Group I subjects were treated at one-week intervals with 10 mg of oral ketorolac, oral placebo, topical ketorolac, and topical placebo, respectively; for each administration modality, the switch between drug and placebo was performed in a randomized, crossover, double-blind fashion. Group II subjects followed the same protocol, with the topical once-daily 0.005% latanoprost treatment starting three days prior to the ketorolac/placebo administration. Intraocular pressure (IOP) was investigated in both groups on the day of oral/topical administration of ketorolac or placebo at baseline (8:00 AM) and at the following intervals: 1, 2, 4, 8, 12, and 24 hours. RESULTS: No significant IOP changes after oral and topical placebo administration were observed in either group. In contrast, when the subjects received ketorolac (either oral or topical), a marked decrease in IOP was recorded, with a noticeable fall at the first hour after the NSAID administration (p = 0.01), which remained still significant 8 hours later (p < 0.05). CONCLUSION: Topical and oral ketorolac strengthens the latanoprost-induced IOP-lowering effect both in glaucomatous patients and in healthy subjects.

Coagulation gene predictors of photodynamic therapy for occult choroidal neovascularization in age-related macular degeneration.

PURPOSE: To determine whether different coagulation-balance genetic polymorphisms explain the variable clinical outcomes of photodynamic therapy with verteporfin (PDT-V) in Caucasian patients with occult subfoveal choroidal neovascularization (CNV) due to age-related macular degeneration (AMD). METHODS: The clinical records of consecutive patients with AMD-related occult CNV, treated with PDT-V for evidence of disease progression, were retrospectively examined. Eighty-four eligible subjects were subdivided into responders and nonresponders based on CNV responsiveness to the first PDT-V over a 3-month period. Six gene polymorphisms (i.e., factor V G1691A, prothrombin G20210A, factor XIII-A G185T, methylenetetrahydrofolate reductase C677T, methionine synthase A2756G, and methionine synthase reductase A66G) were genotyped in each patient. Logistic regression analyses were performed to explore the predictive role of phenotypic and genotypic variables for PDT-V effectiveness. RESULTS: Regression models documented that PDT-V nonresponders were more frequently patients with the hyperfibrinolytic G185T mutation of factor XIII-A (odds ratio [OR], 0.28; 95% confidence interval [CI], 0.11-0.73; P < 0.01). Univariate logistic regression was indicative of an overrepresentation of PDT-V responders among the combined carriers of thrombophilic factor V 1691A and prothrombin 20210A alleles (OR = 3.8; 95% CI: 0.94-15.6; P = 0.07). All the other predictors considered did not significantly influence the short-term CNV responsiveness to PDT-V. CONCLUSIONS: These data provide evidence of the presence of a pharmacogenetic relationship between peculiar coagulation-balance genetic backgrounds and different levels of PDT-V effectiveness in patients with AMD with occult CNV.

12-month retrospective study and review of photodynamic therapy with verteporfin for subfoveal choroidal neovascularization in age-related macular degeneration.

PURPOSE: To evaluate the 12-month visual outcome of photodynamic therapy with verteporfin (PDT-V) for patients with subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration and to verify the predictive role of visual and angiographic factors. METHODS: This retrospective, interventional, consecutive case series study included subjects with different forms of subfoveal CNV. All patients received PDT-V according to Treatment of Age-Related Macular Degeneration With Photodynamic Therapy/Visudyne in Photodynamic Therapy guidelines. A review of medical and angiographic records was performed. RESULTS: Two hundred sixteen patients were divided into 4 study groups: group I, 60 eyes with classic CNV; group II, 56 eyes with predominantly classic CNV; group III, 42 eyes with minimally classic CNV; and group IV, 58 eyes with occult CNV. In groups I and II, best-corrected visual acuity (BCVA) was moderately decreased, without reaching a statistically noticeable level during the entire follow-up; lesion size reduction only reached significance in group I. Groups III and IV showed evident worsening of BCVA (P < 0.05), despite concomitant reduction in CNV size (statistically remarkable only for occult CNV). All study groups exhibited a significant correlation between higher baseline BCVA and better final visual outcome. In groups II and IV, smaller baseline CNV sizes also favorably influenced final BCVA. CONCLUSIONS: Standardized PDT-V minimizes deterioration of central vision only in patients with classic and predominantly classic CNV. Irrespective of the CNV type, better BCVA at presentation represents a good predictive sign. In predominantly classic and occult lesions, minor initial CNV dimension is also a positive prognostic element.

Circadian changes of intraocular pressure and ocular perfusion pressure after timolol or latanoprost in Caucasians with normal-tension glaucoma.

PURPOSE: To evaluate the circadian effects on intraocular pressure (IOP) and ocular perfusion pressure (OPP) of 0.5% timolol or 0.005% latanoprost in Caucasian patients affected by normal-tension glaucoma (NTG). PATIENTS AND METHODS: In this crossover trial, 30 consecutive NTG subjects underwent three 24-hour assessments of IOP, blood pressure (BP), heart rate (HR), and OPP [calculated according to the formula OPP = (1/3 systolic BP + 2/3 diastolic BP) x 2/3 - IOP]: at baseline, and after 1-month treatment with timolol or latanoprost. These parameters were recorded at 4 a.m., 8 a.m., noon, 4 p.m., 8 p.m., and midnight. RESULTS: Both timolol and latanoprost reduced IOP (p < 0.001), with a difference in favour of latanoprost of 1.3 mmHg (95% CI 0.9, 1.6; p < 0.001). After timolol, BP and HR decreased with respect to baseline (p < 0.001). Latanoprost increased mean OPP (3.6 mmHg, 95% CI 2.9, 4.3; p < 0.001), whereas timolol did not improve it. CONCLUSIONS: Latanoprost induces an IOP reduction greater than timolol, also achieving a better circadian flattening of the IOP curve. Only latanoprost significantly increased mean 24-hour OPP. The management of Caucasian NTG patients should be critically realized, considering the 24-hour influence of each IOP-lowering drug on the ocular blood perfusion.

Increased retinal blood flow in patients with active Graves' ophthalmopathy.

PURPOSE: To investigate retinal blood flow by Heidelberg retina flowmeter in patients with active Graves' ophthalmopathy. MATERIALS AND METHODS: Thirty patients with active Graves' ophthalmopathy in euthyroid state and thirty normal controls were enrolled in this study. All subjects underwent heart rate, systolic and diastolic blood pressure detection, complete ophthalmological examination, Hertel's exophthalmometry, and retinal blood flow analysis by Heidelberg retina flowmeter. Patients additionally underwent automated threshold perimetry and extraocular muscle thickness measurement by A-scan ecography. RESULTS: A significant statistical difference was found in exophthalmometry (P<0.001), intraocular pressure (P<0.001) and retinal blood flow (P<0.05) between patients and controls. In patients, muscle enlargement was significantly correlated with retinal blood flow (r=0.49, P=0.005) and proptosis (r=0.37, P=0.04). A significant positive correlation (r=0.52, P=0.002) was also found between intraocular pressure and proptosis. CONCLUSIONS: Active Graves' ophthalmopathy patients present an increased retinal blood flow.

Predictive role of coagulation-balance gene polymorphisms in the efficacy of photodynamic therapy with verteporfin for classic choroidal neovascularization secondary to age-related macular degeneration.

OBJECTIVES: Age-related macular degeneration (AMD) represents the leading cause of blindness in Western populations. The majority of severe vision loss occurs in the exudative form of AMD, characterized by the development of choroidal neovascularization (CNV) beneath the fovea. Photodynamic therapy with verteporfin (PDT-V) represents one of the most largely employed modality that maybe achieves the subfoveal CNV inactivation in AMD patients. Although several ocular factors have been hitherto investigated as predictors, these researches have weakly contributed to PDT-V optimization. As PDT-V benefit is determined by CNV photothrombosis, we have retrospectively studied several coagulation-balance gene polymorphisms as predictors of PDT-V efficacy. METHODS: Ninety Caucasian patients with neovascular AMD were subdivided in responder and nonresponder, on the basis of CNV responsiveness to PDT-V application. Six gene polymorphisms, that is factor V G1691A, prothrombin G20210A, factor XIII-A G185T, methylenetetrahydrofolate reductase C677T, methionine synthase A2756G, and methionine synthase reductase A66G, were genotyped in the entire cohort. RESULTS: Logistic regression models showed that PDT-V responders were more prevalent within patients with prothrombin G20210A mutation [odds ratio (OR)=5.6, 95% confidence interval (CI) (1.2, 27.2), P=0.03], and within methylenetetrahydrofolate reductase 677T carriers [OR=6.9, 95% CI (2.7, 18.1), P<0.001]. Conversely, PDT-V nonresponders were overrepresented in carriers for factor XIII-A 185T [OR=0.13, 95% CI (0.05, 0.36), P<0.001]. CONCLUSION: These results provide evidences for the presence of pharmacogenetic relationship between peculiar coagulation-balance gene polymorphisms and different levels of PDT-V effectiveness in patients with AMD-related CNV.

Effect of 2% dorzolamide on retinal blood flow: a study on juvenile primary open-angle glaucoma patients already receiving 0.5% timolol.

AIM: To investigate whether dorzolamide modifies peripapillary retinal haemodynamics in juvenile primary open-angle glaucoma (JPOAG) patients treated with timolol. METHODS: In 40 JPOAG subjects, before and after dorzolamide coadministration with timolol, the following examinations were achieved: intraocular pressure (IOP), blood pressure (BP), ocular perfusion pressure (OPP), heart rate (HR), visual field and retinal flowmetry. RESULTS: Adjunctive therapy with dorzolamide induced the following modifications: IOP reduction [1.75 mmHg, 95% confidence interval (CI) 1.23, 2.26; P < 0.05], OPP increase (5.09 mmHg, 95% CI 2.97, 7.20; P < 0.02) and retinal blood flow improvement (35.0 arbitrary units, 95% CI 12.20, 57.80; P < 0.03). BP, HR and visual field indices did not change. CONCLUSIONS: Dorzolamide, in association or in fixed combination with timolol, significantly improves retinal blood flow in JPOAG patients.