Filippo Missiroli

Typing of ARMS2 and CFH in age-related macular degeneration: case-control study and assessment of frequency in the Italian population.

OBJECTIVES To determine the effects of the polymorphisms CFH Tyr402His and ARMS2 del443ins54 on susceptibility to age-related macular degeneration (AMD) and to find the frequencies of these single-nucleotide polymorphisms in an Italian population that was not examined clinically. METHODS A total of 286 control subjects (126 men and 160 women) and 159 white patients (73 men and 86 women) harboring exudative AMD in 1 eye were recruited. A third group of 182 DNA samples from blood donors of the same geographical areas were also typed to assess the frequency of CFH Tyr402His and ARMS2 del443ins54 polymorphisms in the general population. The data were analyzed statistically by a standard 2 x 2 table, Fisher exact tests, and odds ratios. RESULTS The deletion-insertion at chromosome 10q26 (del443ins54) showed the strongest association with AMD in terms of both P value and odds ratio (P = 2.7 x 10(-15); odds ratio = 3.25), and a highly significant association was also confirmed for Tyr402His at the CFH locus (P = 9.9 x 10(-13); odds ratio = 2.86). We found no differences in allele and genotype association between classic and occult choroidal neovascularization. We also observed that 39% of the samples in the general Italian population were at least 5.4 times more likely than control subjects to develop AMD. CONCLUSIONS To our knowledge, this is the first confirmation of the association of del443ins54 in Italian patients with AMD, and we also confirmed the association of Tyr402His with CFH. Genetic analysis of the general population suggested that analysis of the ARMS2 and CFH risk alleles alone may be helpful in differentiating high-risk individuals (odds ratio > 5.00) from low-risk individuals (odds ratio < 0.45). CLINICAL RELEVANCE Individuals at high risk for developing AMD could be identified and selected for specific prevention programs. In this context, the development of prevention programs based on dietary antioxidants or on close monitoring of at-risk individuals should be considered or suggested.

Age-Related Macular Degeneration: Insights into Inflammatory Genes

Age-related macular degeneration (AMD) is a progressive neurodegenerative disease that affects approximately 8.7% of elderly people worldwide (>55 years old). AMD is characterized by a multifactorial aetiology that involves several genetic and environmental risk factors (genes, ageing, smoking, family history, dietary habits, oxidative stress, and hypertension). In particular, ageing and cigarette smoking (including oxidative compounds and reactive oxygen species) have been shown to significantly increase susceptibility to the disease. Furthermore, different genes (CFH, CFI, C2, C3, IL-6, IL-8, and ARMS2) that play a crucial role in the inflammatory pathway have been associated with AMD risk. Several genetic and molecular studies have indicated the participation of inflammatory molecules (cytokines and chemokines), immune cells (macrophages), and complement proteins in the development and progression of the disease. Taking into consideration the genetic and molecular background, this review highlights the genetic role of inflammatory genes involved in AMD pathogenesis and progression.

Haplotypes in IL-8 Gene Are Associated to Age-Related Macular Degeneration: A Case-Control Study

Background Age-related macular degeneration (AMD) is the main cause of blindness in the developed world. The etiology of AMD is multifactorial due to the interaction between genetic and environmental factors. IL-8 has a role in inflammation and angiogenesis; we report the genetic characterization of IL-8 allele architecture and evaluate the role of SNPs or haplotypes in the susceptibility to wet AMD, case-control study. Methods Case-control study including 721 AMD patients and 660 controls becoming from Italian population. Genotyping was carried out by Real Time-PCR. Differences in the frequencies were estimated by the chi-square test. Direct sequencing was carried out by capillary electrophoresis trough ABI3130xl. Results rs2227306 showed a p–value of 4.15*10−5 and an Odds Ratio (OR) for T allele of 1.39 [1.19–1.62]. After these positive results, we sequenced the entire IL-8 regulatory and coding regions of 60 patients and 30 controls stratified for their genotype at rs2227306. We defined two different haplotypes involving rs4073 (A/T), rs2227306 (C/T), rs2227346 (C/T) and rs1126647 (A/T): A-T-T-T (p-value: 2.08*10−9; OR: 1.68 [1.43–1.97]) and T-C-C-A (p-value: 7.07*10−11; OR: 0.60 [0.51–0.70]). To further investigate a potential functional role of associated haplotypes, we performed an expression study on RNA extracted from whole blood of 75 donors to verify a possible direct correlation between haplotype and gene expression, failing to reveal significant differences. Conclusions These results suggest a possible secondary role of IL-8 gene in the development of the disease. This paper outlines the importance of association between inflammation and AMD. Moreover IL-8 is a new susceptibility genomic biomarker of AMD.

Combined reduced fluence photodynamic therapy and intravitreal ranibizumab for polypoidal choroidal vasculopathy

Purpose: We performed a prospective noncomparative study to report the results of reduced fluence photodynamic therapy (PDT) combined with intravitreal ranibizumab in patients with polypoidal choroidal vasculopathy with active exudation and hemorrhage. Methods: Seventeen polypoidal choroidal vasculopathy eyes were treated, and follow-up for all patients was 12 months. Photodynamic therapy was administered with reduced fluence (exposure time of 70’’) and followed (48 hours later) by intravitreal ranibizumab (0.5 mg in 50 &mgr;L). Intravitreal ranibizumab, with or without reduced fluence PDT, was repeated as indicated by clinical and angiographic findings. Results: During the follow-up, the mean best-corrected visual acuity significantly improved from 0.45 ± 0.29 logarithm of the minimum angle of resolution at baseline to 0.29 ± 0.28 logarithm of the minimum angle of resolution at 12 months. The mean total macular volume (documented by optical coherence tomography retinal map examination) decreased from 7.5 ± 1.18 mm3 to 6.7 ± 0.8 mm3. In 95% of the cases, best-corrected visual acuity remained stable or improved. Conclusion: Reduced fluence PDT limits laser exposure, minimizing the risks of PDT-induced adverse effects. Intravitreal injections of ranibizumab 0.5 mg reduced bleeding and leakage in polypoidal choroidal vasculopathy eyes and interfere with rebound upregulation of vascular endothelial growth factor because of PDT-induced choroidal hypoperfusion. Combined treatment may improve treatment outcomes in polypoidal choroidal vasculopathy while minimizing ocular and systemic complications of treatment.

Long-term functional and morphologic retinal changes after ranibizumab and photodynamic therapy in myopic choroidal neovascularization

Purpose: To assess and compare the long-term functional and anatomical outcomes in eyes with myopic choroidal neovascularization (CNV) treated with intravitreal injections of ranibizumab or with photodynamic therapy (PDT). Methods: Eighty-five eyes of 85 consecutive patients with myopic CNV and treated with either PDT (43/85) or ranibizumab 0.5 mg (42/85) and at least 24 months of follow-up were collected. Data from the best-corrected visual acuity, optical coherence tomography, and fluorescein angiography were compared between the groups. Differences in the regression pattern of myopic CNV and the rate of chorioretinal atrophy development were also compared between the groups. Results: The effect of treatment over time on best-corrected visual acuity and the central retinal thickness was significantly greater in the ranibizumab group (P = 0.0012 and P < 0.0002, respectively), with eyes treated with ranibizumab showing a significant central retinal thickness decrease since the first visit and maintained until 24 months. The proportion of patients showing a complete closure of CNV was similar between the groups (93% [39 of 42 eyes in the ranibizumab group] vs. 88% [38 of 43 eyes in the PDT group], P = 0.48). Both treatments were associated with an increase of chorioretinal atrophy size, which was greater in the PDT-treated eyes (P = 0.016). Conclusion: Ranibizumab therapy showed a greater long-term efficacy compared with PDT in myopic CNV eyes, with a fewer proportion of eyes developing an increase of lesion and chorioretinal atrophy size.

A microbiological and confocal microscopy study documenting a slime-producing Staphylococcus epidermidis isolated from a nylon corneal suture of a patient with antibiotic-resistant endophthalmitis

BackgroundWe describe a case of posttraumatic endophthalmitis unresponsive to systemic (amoxicillin+clavulanic acid and piperacillin/tazobactam), intra-ocular (vancomycin) and topical (ofloxacin, tetracycline and sulfametoxazole) antibiotic therapy. Microbiological and confocal microscopy studies of a nylon corneal suture revealed the presence of a slime-producing strain of Staphylococcus epidermidis.MethodsWe describe the history and clinical presentation of a 77-year-old man in whom a high-grade posttraumatic endophthalmitis resolved only after the removal of a single nylon corneal suture. Microbiological investigations of the aqueous, vitreous and suture were performed, and the propensity of the suture-associated isolate to form biofilm was assessed using confocal microscopy.ResultsA single stain of S. epidermidis was isolated from both aqueous and vitreous specimens and from the suture. The planktonic form of the isolate was susceptible in vitro to the antibiotics administered to the patient, but the strain was capable of forming biofilms and this phenotype showed resistance to high concentrations of the same antibiotics.ConclusionsThe presence of a slime-producing strain of S. epidermidis should be considered in endophthalmitis that is unresponsive to specific antibiotic therapy, especially in cases in which an intra-ocular foreign body (e.g., a suture) is present.

Modulation of Ku70/80, Clusterin/ApoJ Isoforms and Bax Expression in Indocyanine-Green-Mediated Photo-Oxidative Cell Damage

Purpose: In order to characterize the biological effects and molecular mechanism underlying indocyanine-green (ICG)-mediated photo-oxidative cell damage, human cultured retinal pigmented epithelium (RPE) cells preloaded with ICG were exposed to 810-nm laser irradiation. Cell viability and death induction were examined, as well as the modulation of proteins involved in cell death and DNA repair. Methods: ARPE-19 cells preloaded with 100 µM ICG were irradiated using continuous and micropulsed 810-nm laser for the dye photoactivation, and cell viability and apoptosis were evaluated. The expression and subcellular localization of Bax, Ku70, Ku80 and clusterin/ApoJ were analyzed by immunocytochemistry and Western blot. Results: ICG photoactivation induced apoptosis in RPE cells. The micropulsed laser irradiation induced a higher percentage of cell killing as compared to continuous wave. Cell killing was inhibited by sodium azide, suggesting the involvement of reactive oxygen species in the laser-induced cell damage. Bax was strongly induced after 4 and up to 24 h of treatment. The nuclear proapoptotic isoform of clusterin/ApoJ was selectively upregulated after 24 h of treatment. The DNA repair machinery was upregulated after 4 and up to 24 h. Conclusion: These data elucidate some molecular mechanisms involved in cell death induced by ICG photosensitization. The increase and relocalization of Bax into the mitochondria and the upregulation and translocation of the proapoptotic isoform of clusterin/ApoJ in the nucleus demonstrated the involvement of these proteins in the photo-oxidative cell death pathway. These data point out new molecular targets and suggest potential applications in the therapy of the retinal diseases that could benefit by selective RPE treatment.

Visual disability and quality of life in glaucoma patients

Glaucoma is an optic neuropathy that can result in progressive and irreversible vision loss, thereby affecting quality of life (QoL) of patients. Several studies have shown a strong correlation between visual field damage and visual disability in patients with glaucoma, even in the early stages of the disease. Visual impairment due to glaucoma affects normal daily activities required for independent living, such as driving, walking, and reading. There is no generally accepted instrument for assessing quality of life in glaucoma patients; different factors involved in visual disability from the disease are difficult to quantify and not easily standardized. This chapter summarizes recent works from clinical and epidemiological studies, which describe how glaucoma affects the performance of important vision-related activities and QoL.

Indocyanine Green Angiography and Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration

Purpose To compare the capability of indocyanine green angiography (ICGA) and optical coherence tomography angiography (OCTA) in detecting choroidal neovascularization (CNV). Methods In this prospective study, patients with CNV detected with fluorescein angiography (FA) underwent ICGA and OCTA, spectral domain OCT (SD-OCT), and infrared or fundus color photographs. CNV lesions were outlined on ICGA and OCTA images, and the composition and size of the CNV was documented. Results One hundred eighty-two eyes were included. With ICGA, well-defined lesions were observed in 37.9%, partly defined in 44.5%, and undefined in 17% of eyes. On OCTA, well-defined, partly defined, and undefined vessels were observed in 53.8%, 27.5%, and 18.7% of eyes, respectively. There was a good correlation between CNV size measured with the two instruments (r = 0.84). However, OCTA underestimated CNV area by about 4.5% (slope coefficient with linear regression: 0.55, 95% confidence interval [CI]: 0.46 to 0.65; intercept: 0.27, 95% CI: -0.2 to 0.56). On ICGA, CNV composition was capillary in 28%, mature in 14.3%, and mixed (capillary and major neovascular complex) in 57.7% of eyes. Similarly, OCTA revealed capillary, mature, and mixed CNV in 28.9%, 15.9%, and 55.5% of eyes, respectively. Conclusions OCTA provides the clinician the ability to perform precise structural and vascular assessment of CNV noninvasively. Our study is, to our knowledge, the largest OCTA analysis to date of CNV secondary to neovascular AMD analyzed simultaneously by ICGA and OCTA.

Aging of the Cornea

Unlike other ocular structures, as well as most tissues in the body, the cornea does not show important changes with normal aging. A variety of corneal aging changes have, however, been reported. Few of them are clinically evident, while others are demonstrated by chemical, biological, and structural studies. Distinction has to be made between conditions considered within the normal limits of aging and those of true disease processes that commonly affect the cornea in the elderly. The difference with other ocular structures is that changes of cornea due to aging are mostly asymptomatic and do not usually affect vision, hence they do not require treatment. However, some changes occur and, for example, the aged cornea becomes more susceptible to infection because of a decreased ability to resist a variety of physiological stresses. Furthermore, it is sometimes difficult to distinguish age specific deterioration from degenerations modified by environmental and genetic factors. The well-known clinical conditions that occur with age in the cornea will be described first. Then, a review of the effect of age on shape and different aspects of the cornea and its structural (anatomical) changes will be reported.