Genetic variants near TIMP3 and high-density lipoprotein-associated loci influence susceptibility to age-related macular degeneration.

We executed a genome-wide association scan for age-related macular degeneration (AMD) in 2,157 cases and 1,150 controls. Our results validate AMD susceptibility loci near CFH (P < 10(-75)), ARMS2 (P < 10(-59)), C2/CFB (P < 10(-20)), C3 (P < 10(-9)), and CFI (P < 10(-6)). We compared our top findings with the Tufts/Massachusetts General Hospital genome-wide association study of advanced AMD (821 cases, 1,709 controls) and genotyped 30 promising markers in additional individuals (up to 7,749 cases and 4,625 controls). With these data, we identified a susceptibility locus near TIMP3 (overall P = 1.1 x 10(-11)), a metalloproteinase involved in degradation of the extracellular matrix and previously implicated in early-onset maculopathy. In addition, our data revealed strong association signals with alleles at two loci (LIPC, P = 1.3 x 10(-7); CETP, P = 7.4 x 10(-7)) that were previously associated with high-density lipoprotein cholesterol (HDL-c) levels in blood. Consistent with the hypothesis that HDL metabolism is associated with AMD pathogenesis, we also observed association with AMD of HDL-c-associated alleles near LPL (P = 3.0 x 10(-3)) and ABCA1 (P = 5.6 x 10(-4)). Multilocus analysis including all susceptibility loci showed that 329 of 331 individuals (99%) with the highest-risk genotypes were cases, and 85% of these had advanced AMD. Our studies extend the catalog of AMD associated loci, help identify individuals at high risk of disease, and provide clues about underlying cellular pathways that should eventually lead to new therapies.

Bilateral, symmetric and simultaneous rhegmatogenous retinal detachment. Predisposition or coincidence? A case report.

The following is a case report of a 65-year-old patient who had previously been diagnosed with primary open-angle glaucoma and who was experiencing a sudden loss of both visual acuity and of superior visual field in both eyes. In the ophthalmological examination, a bilateral, symmetric rhegmatogenous retinal detachment that affected the inferior quadrants of both eyes was detected. The retinal detachment was caused by a retinal horseshoe break located at the equator of 6 h in each eye. The factors that could determine the predisposition for and/or the coincidence of bilateral and symmetric rhegmatogenous retinal detachment will be discussed.

Confocal microscopy and histopathological examination of diffuse lamellar keratitis in an experimental animal model.

PURPOSE: To investigate the cell populations and structural alterations of the cornea in an experimental model of diffuse lamellar keratitis (DLK) using confocal microscopy and histopathology. METHODS: A corneal flap was cut in 22 eyes of 11 New Zealand rabbits and the stromal interface was exposed to balanced salt solution (BSS, BSS group) and Pseudomonas aeruginosa lipopolysaccharide (LPS) endotoxin (5 mg/mL) (LPS 5 mg/mL group) and (3.5 mg/mL) (LPS 3.5 mg/mL group). Postoperatively, eyes were examined with a slit-lamp microscope (DLK grading) and confocal microscopy. Animals were sacrificed on day 3 (BSS group and LPS 5 mg/mL group) and day 4 (LPS 3.5 mg/mL group). Corneoscleral buttons were excised and processed for histopathologic examination. RESULTS: Seven eyes were excluded. Slit-lamp microscopy revealed no cellular infiltration in the BSS group (five eyes). In the LPS groups, all eyes developed DLK, with iritis only observed in grade III eyes. In the LPS 5 mg/mL group, four eyes had DLK grade III, with iritis in three eyes. In the LPS 3.5 mg/mL group, three eyes had grade II and three eyes had grade III with iritis. On confocal microscopy, the BSS group had no cellular infiltration. Dense accumulation of inflammatory cells at the interface was noted in both LPS groups. Histopathology in the BSS group had a normal appearance. In the LPS groups, an inflammatory infiltrate was present at the interface that consisted of three cell populations--eosinophils, neutrophils, and lymphocytes. CONCLUSIONS: Lipopolysaccharide endotoxin induced DLK in all exposed eyes, with iritis in a considerable proportion of eyes. The infiltrate consisted of three cell populations. Confocal microscopy showed the infiltrate in all affected eyes. Histopathological and confocal microscopic findings correlated well with the clinical appearance.

Combined photodynamic therapy and intravitreal triamcinolone acetonide for the treatment of myopic subfoveal choroidal neovascularization.

PURPOSE: To evaluate visual acuity changes and safety of combined treatment with photodynamic therapy (PDT) and intravitreal triamcinolone acetonide (IVTA) in myopic eyes with choroidal neovascularization (CNV). DESIGN: Prospective interventional case series. METHODS: Twelve eyes of 12 patients with subfoveal myopic CNV were treated with PDT followed by IVTA within a week. Changes in visual acuity and possible complications related to the combined therapy were assessed in periodic visits. RESULTS: After combined therapy, a significant increase in mean visual acuity was observed at one, three, and six months. A significant increase of mean intraocular pressure was observed after seven days, one month, and three months. Ten patients (83%) required topical antiglaucomatous therapy during follow-up. CONCLUSIONS: The combination of PDT and IVTA may increase the possibility of improving or stabilizing visual acuity in patients with subfoveal myopic CNV, but further studies are needed to asses the effects of this treatment.

Prophylactic perioperative antiviral therapy for LASIK in patients with inactive herpetic keratitis.

PURPOSE: To report the outcome of LASIK in patients with inactive herpetic keratitis in which perioperative antiviral prophylaxis was used to prevent the recurrence of ocular herpes. METHODS: We report an uncontrolled series of five patients with inactive herpetic keratitis for at least 1 year before surgery in whom LASIK was successfully performed. All patients showed normal topography, pachymetry, and corneal sensitivity with no central corneal scarring. Perioperative prophylaxis was used in each case with oral valacyclovir and topical acyclovir ointment. RESULTS: None of the eyes developed reactivation of herpetic keratitis during follow-up. CONCLUSIONS: This study suggests that perioperative antiviral prophylaxis may protect the cornea from herpes simplex virus reactivation after LASIK.

Confocal microscopy of stage 4 diffuse lamellar keratitis with spontaneous resolution.

PURPOSE: To report confocal microscopic findings at the onset of stage 4 diffuse lamellar keratitis and after its resolution. Stage 4 is the most severe form of diffuse lamellar keratitis. Its incidence is approximately 1 in 5000 and is associated with stromal melting, deep flap folds, central haze, hyperopic shift, irregular astigmatism, and severe decrease in visual acuity. METHODS: A 22-year-old woman underwent bilateral uncomplicated laser in situ keratomileusis (LASIK) for myopia. Postoperative course in the right eye was uneventful; however, in the left eye, stage 4 diffuse lamellar keratitis developed. Confocal microscopy examination was performed in both eyes at the onset of the syndrome and after its resolution. Findings in the eye with diffuse lamellar keratitis (left eye) were compared with the uninvolved (right) eye. RESULTS: The condition improved spontaneously and 2 years later, slit-lamp microscopy showed resolution of the folds and haze with subsequent improvement of visual acuity. However, confocal microscopic examination in the left eye revealed a persistent stromal subclinical haze on both sides of the lamellar cut and prominent folds that extended into the anterior stroma. CONCLUSION: Confocal microscopy revealed that in spite of normal appearance on slit-lamp microscopy, micromorphological alterations persisted after spontaneous resolution of stage 4 diffuse lamellar keratitis.

Confocal microscopy in late-onset diffuse lamellar keratitis after laser in situ keratomileusis.

This article reports a case of diffuse lamellar keratitis, without exposure of the flap interface, that developed in a patient who underwent intraepithelial photorefractive keratectomy 1 year after bilateral LASIK. Confocal microscopy was performed in both eyes at the onset of the diffuse lamellar keratitis and after its resolution. In the eye with diffuse lamellar keratitis, abundant round structures (inflammatory cells) were present at the interface; these structures disappeared after the keratitis resolved and were not present in the contralateral eye at any time. These confocal microscopic findings further support the hypothesis that diffuse lamellar keratitis is a nonspecific inflammatory response in corneas with a lamellar interface.

Vasoproliferative tumors of ocular fundus: ultrasonographic characteristics.

The aim of this work is to describe ultrasonographic features in vasoproliferative tumors of ocular fundus (VPTOF). The charts of eight patients were retrospectively studied. Clinical data obtained by complete ophthalmologic examination and ultrasonographic findings were analyzed. Nodular masses affecting either the retina alone or the retina and the choroid were found. The surface contour of the tumor was regular in 5 and irregular in 3 cases. In dimensions, the mean (+/- SD) major base was 7.14 +/- 2.56 mm, minor base 6.74 +/- 2.48 mm, and height 2.38 +/- 1.26 mm. Internal structure was always solid and irregular, while reflectivity was mostly medium, and high in 6 eyes. Kappa angle was not present in any case. No signs of vascularity were detected. According to the results, it is suggested that ultrasonographic examination be performed along with ophthalmoscopy on differential diagnosis of VPTOF.

Ultrasonographic findings in circumscribed choroidal hemangioma after photodynamic therapy.

Circumscribed choroidal hemangioma (CCH) is a benign and relatively rare tumor located posteriorly to the equator. The most frequently associated clinical finding is an exudative retinal detachment (ERD). The aim of this work is to describe ultrasonographic findings in eyes diagnosed with CCH + ERD after photodynamic therapy (PDT). Five eyes of five patients diagnosed with CCH (2 men and 3 women; 3 right eyes and 2 left eyes; mean age 50.6 (range 42-63) years) were referred to the Unit of Ocular Oncology. All cases were selected for PDT since all of them showed a macula-off ERD and hence poor visual acuity. The PDT protocol consisted of verteporfin 6 mg/m2 body surface area and exposure to laser light dose at 689 nm at an intensity of 600 mW/cm2 (1 to 3 sessions depending on the persistence of ERD). Ultrasonographic examination was performed by use of the I3-ABD System (posterior segment 10 MHz B-scan and 8 MHz standardized diagnostic A-scan probes, Innovative Imaging Inc., Sacramento, CA, USA). Ultrasonographic findings recorded on the first examination were consistent with those previously described for CCH in the literature. Dimensions of the tumors were very similar in all cases. However, after PDT we detected significant reduction of the height of the tumor and increased reflectivity, without changes in internal structure. Moreover, we detected retinal reattachment in all cases and therefore a slight improvement in visual acuity. Significant changes in ultrasonographic findings can be found after PDT for CCH.

Genetic association study of age-related macular degeneration in the Spanish population.

PURPOSE: To investigate new genetic risk factors and replicate reported associations with advanced age-related macular degeneration (AMD) in a prospective case-control study developed with a Spanish cohort. METHODS: Three hundred and fifty-three unrelated patients with advanced AMD (225 with atrophic AMD, 57 with neovascular AMD, and 71 with mixed AMD) and 282 age-matched controls were included. Functional and tagging SNPs in 55 candidate genes were genotyped using the SNPlex™ genotyping system. Single SNP and haplotype association analysis were performed to determine possible genetic associations; interaction effects between SNPs were also investigated. RESULTS: In agreement with previous reports, ARMS2 and CFH genes were strongly associated with AMD in the studied Spanish population. Moreover, both loci influenced risk independently giving support to different pathways implicated in AMD pathogenesis. No evidence for association of advanced AMD with other previous reported susceptibility genes, such as CST3, CX3CR1, FBLN5, HMCN1, PON1, SOD2, TLR4, VEGF and VLDLR, was detected. However, two additional genes appear to be candidate markers for the development of advanced AMD. A variant located at the 3' UTR of the FGF2 gene (rs6820411) was highly associated with atrophic AMD, and the functional SNP rs3112831 at ABCA4 showed a marginal association with the disease. CONCLUSION: We performed a large gene association study in advanced AMD in a Spanish population. Our findings show that CFH and ARMS2 genes seem to be the principal risk loci contributing independently to AMD in our cohort. We report new significant associations that could also influence the development of advanced AMD. These findings should be confirmed in further studies with larger cohorts.

Predictors for visual field progression and the effects of treatment with dorzolamide 2% or brinzolamide 1% each added to timolol 0.5% in primary open-angle glaucoma.

PURPOSE: This study aims to identify progression factors in patients with primary open-angle glaucoma (POAG), including the effects of treatment with dorzolamide 2% or brinzolamide 1%, each added to timolol 0.5%. METHODS: A sample of 161 POAG patients were prospectively randomized to receive either dorzolamide 2% (DT) or brinzolamide 1% (BT) b.i.d., each added to timolol 0.5%, during a 60-month, evaluator-masked study. Progression was determined by perimetric criteria. Factors associated with visual field progression were estimated using a conditional Cox hazard model with patient intraclass correlation and were expressed as hazard ratios (HRs) with 95% confidence intervals (95% CIs). RESULTS: Predictive baseline factors were lower diastolic blood pressure (DBP), lower mean arterial pressure (MAP), antihypertensive treatment, lower end-diastolic velocity (EDV) in the ophthalmic artery (OA) and short posterior ciliary artery (SPCA), and a higher resistivity index (RI) in the OA and SPCA. Progression risk decreased by approximately 30% and 20% with each centimetre per second increase of EDV in the OA and SPCA, respectively, from baseline to the last follow-up visit. Each RI decrease (or increase) of 0.01 unit in the OA or SPCA was associated with an approximate 20% decrease (or increase) in risk for progression. In a multivariate analysis, progression risk was significantly lower in eyes treated with DT (HR=0.65, 95% CI 0.41-0.90) compared with those treated with BT. CONCLUSIONS: Progression increased with lower DBP, lower MAP, antihypertensive medication, lower EDV in the OA and SPCA, and higher RI in the OA and SPCA. The risk for progression in patients treated with DT was half that in patients treated with BT.

A comparison of the long-term effects of dorzolamide 2% and brinzolamide 1%, each added to timolol 0.5%, on retrobulbar hemodynamics and intraocular pressure in open-angle glaucoma patients.

PURPOSE: To compare the effect on the retrobulbar hemodynamics and intraocular pressure (IOP) of dorzolamide 2% and brinzolamide 1%, each added to timolol 0.5% in patients with primary open-angle glaucoma (POAG). METHODS: 146 POAG patients were prospectively randomized to receive either dorzolamide 2% or brinzolamide 1% BID, each added to timolol 0.5%, during a 60-month evaluator-masked study. At baseline and every 6 months for 60 months, we measured the retrobulbar hemodynamic parameters in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCA) using color Doppler imaging (CDI), intraocular pressure (IOP), and blood pressure measurements. RESULTS: Dorzolamide significantly increased the end-diastolic velocity (EDV) in the OA in 1.22 cm/s, 95% confidence interval (95% CI) 0.90-1.56 cm/s, P < 0.001 and reduced the resistivity index (RI) in the OA in 0.04 units, 95% CI 0.03-0.05, P < 0.001. None of the retrobulbar parameters changed significantly on therapy with brinzolamide when the results were analyzed at month 60. Both dorzolamide and brinzolamide significantly decreased IOP (-4.3, 95% CI -4.5 to -4.2 mmHg and -4.3, 95% CI -4.4 to -4.2 mmHg, respectively). Dorzolamide significantly reduced the RI in the OA from 0.74 (0.02) to 0.70 (0.02), CRA from 0.66 (0.02) to 0.62 (0.02), and SPCA from 0.66 (0.02) to 0.62 (0.02), P < 0.001, respectively. CONCLUSIONS: Our results suggest augmented retrobulbar blood flow after 5 years of treatment with dorzolamide but not with brinzolamide, each added to timolol, in POAG patients.

Posterior vitreous findings in cases of spontaneous retinal reattachment.

PURPOSE: To describe the posterior vitreous findings in two patients with retinal detachment who experienced spontaneous retinal reattachment. DESIGN: Two observational case reports. TESTING: Biomicroscopic and high-resolution echographic evaluation of the vitreoretinal relationships. MAIN OUTCOME MEASURES: Retinal reattachment and echographic vitreoretinal relationships. RESULTS: Two patients, one with a rhegmatogenous retinal detachment and one with a tractional retinal detachment, were noted to have a partial posterior vitreous detachment with vitreoretinal adherence at the time of presentation. Spontaneous retinal reattachment occurred in both cases, with echography showing complete vitreous separation from the retina. CONCLUSIONS: Complete posterior vitreous detachment may release tractional components in retinal detachment and contribute to spontaneous retinal reattachment.

Amniotic membrane as support for human retinal pigment epithelium (RPE) cell growth.

PURPOSE: The aim of this work was to culture human retinal pigment epithelium (hRPE) cells over human amniotic membrane (hAM). Human AM was studied for its viability as an adequate support for transplantation of an hRPE cell monolayer with preserved cell polarity to the subretinal space. METHODS: Human AM was obtained from pregnant women during caesarean section. The hAM was sectioned and the pieces were fixed to culture dishes. Human RPE cells were cultured from adult corneal donors and were seeded over hAM. Phase-contrast photographs were obtained. Selected specimens were processed by transmission electronic microscopy (TEM). RESULTS: The attachment and growth of hRPE cells over hAM was observed. Human RPE cells constituted tight colonies that maintained epithelial phenotype. Using TEM, we identified a monolayer of hRPE cells, with cuboidal to spheroidal morphology. These cells showed integration with the substrate and cell-cell contacts were detected. CONCLUSION: Amniotic membrane may be a suitable substrate for hRPE growth. Further studies are required in order to determine the viability of hRPE on hAM in the subretinal space.

Abnormal cell cycle regulation in primary human uveal melanoma cultures.

Uveal malignant melanoma is the most frequent primary intraocular tumor in adult humans. The cellular events leading to neoplasic transformation of normal uveal melanocytes are not well known when compared to other cancers. In this study, we investigated the role of G1 and G1/S regulatory proteins of the cell cycle in human uveal melanoma (UM) primary cell cultures, since these proteins are common targets in tumor development. Further, freshly established and characterized tumor cells are a better model for in vitro studies when compared to cell lines established long ago. Human primary cell cultures from eight different UM were established, as well as one primary culture from rhesus uveal normal melanocytes (UNM). Primary human UM cultures were characterized by a low establishment and growing rate. From four successful cultures, three showed a high expression of cyclin D1, cyclin E, p16NK4A, and p27KIP1 with no variations in cyclin A, cyclin-dependent kinase 2 (CDK2), and CDK4. Interestingly, in one of the cultured tumors, tumor suppressor protein retinoblastoma (Rb) did not bind E2F despite the fact that Rb was found in its hypophosphorylated form. No mutations in either RB1 or the Rb-binding pocket of E2F-1 were detected. Furthermore, we identified seven proteins co-immunoprecipitating with Rb in this tumor, including Lamin A/C and six proteins not previously reported to bind Rb: Hsc70, high mobility group protein 1 (HMG-1), hnRPN, glyceraldehyde 3 phosphate dehydrogenase (G3PDH), EF-1, and EF-2. Our results indicate that the overexpression of cyclins D1/E and CDKIs p16 and p27, together with a deregulation of the Rb/E2F pathway, may be implicated in the development of human UM.

Biomicroscopia ultrasónica en oftalmología

Monografía accesible a texto completo en formato html que consta de introducción y doce capítulos, entre los que se encuentran: bases físicas de la biomicroscopia ultrasónica, instrumentación y práctica de la exploración bioultrasónica, biomicroscopia ultrasónica del globo ocular normal, tumores intraoculares del segmento anterior, etc.