A prospective multicenter study on genome wide associations to ranibizumab treatment outcome for age-related macular degeneration

We conducted a genome-wide association study (GWAS) on the outcome of anti-VEGF treatment for exudative age-related macular degeneration (AMD) in a prospective cohort. Four hundred and sixty-one treatment-naïve AMD patients were recruited at 13 clinical centers and all patients were treated with 3 monthly injections of ranibizumab followed by pro re nata regimen treatment for one year. Genomic DNA was collected from all patients for a 2-stage GWAS on achieving dry macula after the initial treatment, the requirement for an additional treatment, and visual acuity changes during the 12-month observation period. In addition, we evaluated 9 single-nucleotide polymorphisms (SNPs) in 8 previously reported AMD-related genes for their associations with treatment outcome. The discovery stage with 256 patients evaluated 8,480,849 SNPs, but no SNPs showed genome-wide level significance in association with treatment outcomes. Although SNPs with P-values of <5 × 10⁻⁶ were evaluated in replication samples of 205 patients, no SNP was significantly associated with treatment outcomes. Among AMD-susceptibility genes, rs10490924 in ARMS2/HTRA1 was significantly associated with additional treatment requirement in the discovery stage (P = 0.0023), and pooled analysis with the replication stage further confirmed this association (P = 0.0013). ARMS2/HTRA1 polymorphism might be able to predict the frequency of injection after initial ranibizumab treatment.

Glaucomatous changes in lamina pores shape within the lamina cribrosa using wide bandwidth, femtosecond mode-locked laser OCT

PURPOSE

The lamina cribrosa (LC) is known to play a critical role in the pathogenesis of glaucoma. Although it has been reported that striae-shaped or slit-shaped lamina pores are more frequent in eyes with primary open angle glaucoma (POAG), this observation is based only on fundus photography. The primary object of this study is to perform layer-by-layer comparisons of the shape of lamina pores within the LC in vivo.

DESIGN

Cross-sectional study.

METHODS

Optic nerve head B-scans were obtained using custom-made broad-wavelength optical coherence tomography with a mode-locked laser. A total of 300 single B-scans per eye were obtained and three-dimensional images were rendered from these image sequences to obtain 2-μm thin-slice en face images of the LC. Elongation indices (EIs) of the lamina pores were measured from the anterior surface (AS) of the LC to the deeper layers in 40-μm increments.

RESULTS

Thirteen eyes from 10 primary open angle glaucoma (POAG) patients of mean deviation -15.2 (-16.5, -12.9) (median [25,75 percentile]) dB and 10 eyes from 7 normal controls were studied. Although the EI value was not significantly different between the superior, temporal and inferior regions of the LC at any depth level in either group, it was greater at the AS than at the 40 μm and 80 μm depth levels (P < .001) in both groups, and was greater in the POAG group only at the AS and 40 μm depth level (P ≤ .05). After adjustment for age and refraction, the effects of depth and presence of POAG on the EI value remained significant. Also, the severity of glaucoma and depth were significant factors associated with EI in multivariate analysis.

CONCLUSIONS

Elongation of lamina pores was significantly more evident at the anterior surface and the 40-μm depth level of the LC in POAG eyes than in normal eyes, suggesting that nerve fiber bundles passing through the LC were under greater stress in the anterior layers of the LC.

Vertical asymmetry of lamina cribrosa tilt angles using wide bandwidth, femtosecond mode-locked laser OCT; effect of myopia and glaucoma

Purpose

Morphological features of the lamina cribrosa (LC) and optic disc may be important in the pathogenesis of glaucoma and myopic neuropathy. We therefore performed a cross-sectional study of patients with glaucoma and myopic neuropathy to evaluate vertical asymmetry of LC tilt angles (LCTAs) from Bruch’s membrane opening (BMO).

Material and methods

Forty-six control eyes and 35 primary open-angle glaucoma (POAG) eyes were included. A raster scanning protocol with 300 single B-scans (without averaging) were obtained using optical coherence tomography with a wide-bandwidth, femtosecond mode-locked (ML) laser. Superior temporal to inferior nasal (ST) direction and inferior temporal to superior nasal (IT) direction (±45° rotation with a horizontal line) lines were drawn, and the angle between the inner edge of the BMO plane and the best fitting line for the anterior LC plane was measured as the LCTA. The generalized estimating equation was used to analyze the eye-derived data.

Results

Although no significant differences in either ST-LTCAs or IT-LTCAs were observed between the glaucoma group and non-glaucoma group, the IT-LCTAs were found to be significantly greater than the ST-LCTA in both the glaucoma and non-glaucoma groups (P < 0.001). After adjustment for other potential confounding factors by multivariate analysis, greater refractive errors were significantly correlated with IT-LCTAs.

Conclusions

Vertical asymmetry of the LC tilting from the BMO plane exists in both normal and POAG eyes, and correlates with the degree of myopia.

Generation of broadband noise-like pulse from Yb-doped fiber laser ring cavity

We have demonstrated a generation of the noise-like pulse (NLP) with broadband spectrum in a nonlinear polarized evolution-based passive mode-locked Yb-doped fiber (YDF) ring laser. At the cavity dispersion of near zero, the NLP with spectrum bandwidth up to 131 nm (FWHM) was obtained at a central wavelength of 1070 nm with output power of 136 mW and 80 MHz repetition rate. To our best knowledge, this spectrum bandwidth of NLP is the broadest among the reported YDF lasers. The autocorrelation function of pulse contained the short (30 fs) and long (4.6 ps) components. This short coherence light source is well suited for the optical coherent tomography used for ophthalmology at a wavelength of ∼1000  nm.

New loci and coding variants confer risk for age-related macular degeneration in East Asians

Age-related macular degeneration (AMD) is a major cause of blindness, but presents differently in Europeans and Asians. Here, we perform a genome-wide and exome-wide association study on 2,119 patients with exudative AMD and 5,691 controls, with independent replication in 4,226 patients and 10,289 controls, all of East Asian descent, as part of The Genetics of AMD in Asians (GAMA) Consortium. We find a strong association between CETP Asp442Gly (rs2303790), an East Asian-specific mutation, and increased risk of AMD (odds ratio (OR)=1.70, P=5.60 × 10⁻²²). The AMD risk allele (442Gly), known to protect from coronary heart disease, increases HDL cholesterol levels by 0.17 mmol l⁻¹ (P=5.82 × 10⁻²¹) in East Asians (n=7,102). We also identify three novel AMD loci: C6orf223 Ala231Ala (OR=0.78, P=6.19 × 10⁻¹⁸), SLC44A4 Asp47Val (OR=1.27, P=1.08 × 10⁻¹¹) and FGD6 Gln257Arg (OR=0.87, P=2.85 × 10⁻⁸). Our findings suggest that some of the genetic loci conferring AMD susceptibility in East Asians are shared with Europeans, yet AMD in East Asians may also have a distinct genetic signature.

Age-related macular degeneration (AMD) is a major cause of blindness worldwide. Here, the authors carry out a two-stage genome-wide association study for AMD and identify three new AMD risk loci, highlighting the shared and distinct genetic basis of the disease in East Asians and Europeans.

Correlation between lamina cribrosa tilt angles, myopia and glaucoma using OCT with a wide bandwidth femtosecond mode-locked laser

Purpose

To measure horizontal and vertical lamina cribrosa (LC) tilt angles and investigate associated factors using prototype optical coherence tomography (OCT) with a broad wavelength laser light source.

Design

Cross sectional study.

Methods

Twenty-eight no glaucoma eyes (from 15 subjects) and 25 glaucoma eyes (from 14 patients) were enrolled. A total of 300 optic nerve head B-scans were obtained in 10 µm steps and the inner edge of Bruch's membrane opening (BMO) was identified as the reference plane. The vertical and horizontal angles between BMO line and approximate the best-fitting line for the surface of the LC were measured and potential associated factors were estimated with univariate and multivariate logistic regression analyses.

Results

The median (interquartile range) horizontal and vertical tilt angles were 7.10 (2.43–11.45) degrees and 4.15 (2.60–6.85) degrees in eyes without glaucoma and 8.50 (4.40–14.10) degrees and 9.30 (6.90–14.15) degrees in glaucoma eyes, respectively. The refractive errors had a statistically significant association with horizontal LC tilt angles (coefficients, −1.53 per diopter) and glaucoma had a significant correlation with vertical tilt angles (coefficients, 6.56) using multiple logistic regression analysis (p<0.001).

Conclusions

OCT allowed evaluation of the internal tilting of the LC compared with the BMO. The horizontal internal LC tilt angle was correlated with refractive errors, corresponding to myopic physiological changes, and vertical internal LC tilt was correlated with glaucoma, corresponding to glaucomatous pathological changes. These parameters have important implications for investigation of the correlation between myopia, glaucoma and LC morphological features.

Three-dimensional optic nerve head images using optical coherence tomography with a broad bandwidth, femtosecond, and mode-locked laser

Purpose

The aim of this study was to demonstrate the fine laminar structure of the optic nerve head (ONH), in vivo, using a broad wavelength, ultra-high resolution, and optically coherent tomography (OCT) system.

Methods

This high-resolution OCT system, based on a 200 nm bandwidth spectrometer and an 8 femtosecond ultra-short, mode-locked, coherent laser light source, enabled in vivo cross-sectional ONH imaging with 2.0 μm axial resolution. A total of 300 optic disc B-scans, which consisted of 300 × 2048 pixels, were obtained in 10 μm steps. Three-dimensional images were rendered from these images to obtain n face images of the optic disc. Fundus photography, scanning laser ophthalmoscopy (SLO), and standard OCT were also performed for all subjects.

Results

Thirty-six eyes of normal subjects and ten eyes of glaucoma patients with mean age of 40.0 ± 10.0 years were enrolled in this study. Sequential en face images, from the ONH surface to deeper layers, were reconstructed in 2.0 μm steps. Observation of the images indicated variations in the shape and arrangement of the lamina pores at different depths. Clear lamina pores were identified by this technique in 44 eyes, compared with the fundus camera (identified in six eyes), SLO (identified in 14 eyes), and standard OCT (identified in 24 eyes) (all comparisons, p < 0.001).

Conclusions

The fine structure of the ONH could be resolved in vivo using our OCT, providing improved imaging that can be used in research and clinical applications for a better characterization of the anatomical and pathological features associated with glaucoma.

Electronic supplementary material

The online version of this article (doi:10.1007/s00417-014-2870-5) contains supplementary material, which is available to authorized users.

Prognostic phenotypic and genotypic factors associated with photodynamic therapy response in patients with age-related macular degeneration

BACKGROUND

This study aimed to demonstrate the phenotypic and genotypic factors associated with photodynamic therapy (PDT) for age-related macular degeneration (AMD).

METHODS

The study included 149 patients with exudative AMD treated by PDT. Eight phenotypic factors and ten genotypic factors for three single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996) in the complement factor H (CFH) gene, rs 11200638-SNP in the high temperature requirement A-1 (HTRA1) gene, two SNPs (rs699947, rs2010963) in the vascular endothelial growth factor (VEGF) gene, and four SNPs (rs12948385, rs12150053, rs9913583, rs1136287) in the pigment epithelium-derived factor (PEDF) gene were evaluated.

RESULTS

A significant association with best-corrected visual acuity change was demonstrated in the greatest linear dimension, presence or absence of pigment epithelial detachment, and HTRA1-rs11200638 genotype statistically (P=3.67×10(-4), 1.95×10(-2), 1.24×10(-3), respectively). Best-corrected visual acuity in patients with AA genotype of HTRA1-rs11200638 significantly decreased compared with that in patients with GG genotype (P=1.33×10(-3)). Logistic regression analyses demonstrated HTRA1-rs11200638 genotype was most strongly associated with best-corrected visual acuity outcome from baseline at 12 months after photodynamic therapy (P=4.60×10(-3); odds ratio 2.363; 95% confidence interval 1.303-4.285).

CONCLUSION

The HTRA1-rs11200638 variant showed the most significant association. Therefore, this variant may be used as a prognostic factor to estimate the PDT response with significant predictive power.

A genome-wide association study for diabetic retinopathy in a Japanese population: potential association with a long intergenic non-coding RNA

Elucidation of the genetic susceptibility factors for diabetic retinopathy (DR) is important to gain insight into the pathogenesis of DR, and may help to define genetic risk factors for this condition. In the present study, we conducted a three-stage genome-wide association study (GWAS) to identify DR susceptibility loci in Japanese patients, which comprised a total of 837 type 2 diabetes patients with DR (cases) and 1,149 without DR (controls). From the stage 1 genome-wide scan of 446 subjects (205 cases and 241 controls) on 614,216 SNPs, 249 SNPs were selected for the stage 2 replication in 623 subjects (335 cases and 288 controls). Eight SNPs were further followed up in a stage 3 study of 297 cases and 620 controls. The top signal from the present association analysis was rs9362054 in an intron of RP1-90L14.1 showing borderline genome-wide significance (P_met = 1.4×10⁻⁷, meta-analysis of stage 1 and stage 2, allele model). RP1-90L14.1 is a long intergenic non-coding RNA (lincRNA) adjacent to KIAA1009/QN1/CEP162 gene; CEP162 plays a critical role in ciliary transition zone formation before ciliogenesis. The present study raises the possibility that the dysregulation of ciliary-associated genes plays a role in susceptibility to DR.

Ocular localization and transduction by adenoviral vectors are serotype-dependent and can be modified by inclusion of RGD fiber modifications

Purpose

To evaluate localization and transgene expression from adenoviral vector of serotypes 5, 35, and 28, ± an RGD motif in the fiber following intravitreal or subretinal administration.

Methods

Ocular transduction by adenoviral vector serotypes ± RGD was studied in the eyes of mice receiving an intravitreous or subretinal injection. Each serotype expressed a CMV-GFP expression cassette and histological sections of eyes were examined. Transgene expression levels were examined using luciferase (Luc) regulated by the CMV promoter.

Results

GFP localization studies revealed that serotypes 5 and 28 given intravitreously transduced corneal endothelial, trabecular, and iris cells. Intravitreous delivery of the unmodified Ad35 serotype transduced only trabecular meshwork cells, but, the modification of the RGD motif into the fiber of the Ad35 viral vector base expanded transduction to corneal endothelial and iris cells. Incorporation of the RGD motif into the fiber knob with deletion of RGD from the penton base did not affect the transduction ability of the Ad5 vector base. Subretinal studies showed that RGD in the Ad5 knob shifted transduction from RPE cells to photoreceptor cells. Using a CMV-Luc expression cassette, intravitreous delivery of all the tested vectors, such as Ad5-, Ad35- and Ad28- resulted in an initial rapid induction of luciferase activity that thereafter declined. Subretinal administration of vectors showed a marked difference in transgene activity. Ad35-Luc gene expression peaked at 7 days and remained elevated for 6 months. Ad28-Luc expression was high after 1 day and remained sustained for one month.

Conclusions

Different adenoviral vector serotypes ± modifications transduce different cells within the eye. Transgene expression can be brief or extended and is serotype and delivery route dependent. Thus, adenoviral vectors provide a versatile platform for the delivery of therapeutic agents for ocular diseases.

[Corneal subepithelial infiltrates that developed following intravitreous injection of bevacizumab]

BACKGROUND

Anti-vascular endothelial growth factor (anti-VEGF) therapies including intravitrous bevacizumab injection (IVB) emerged as an effective treatment for various fundus diseases. Reports of adverse reactions derived from bevacizumab itself are rare. We report a case in which corneal subepithelial infiltrates developed following IVB.

CASE

A sixty-six-year-old man presented with visual acuity loss due to cystic macular edema secondary to branch retinal vein occlusion. He developed vascular congestion and subepithelial infiltrates in the peripheral cornea on day 2 following the first IVB. The findings resolved with topical steroid in twelve days.

CONCLUSION

A case of subepithelial infiltrate in the peripheral cornea following IVB is reported. Since infiltrates were located along, and associated with the congestion of, the limbal vascular arcade, an innate immune response to bevacizumab may be indicated.

Five-year results of photodynamic therapy with verteporfin for Japanese patients with neovascular age-related macular degeneration

Purpose

To describe the treatment outcome of photodynamic therapy (PDT) in Japanese patients with age-related macular degeneration (AMD) followed for 5 years.

Patients and methods

We retrospectively reviewed clinical charts of 51 patients with AMD. Thirty-one eyes of typical AMD (tAMD) and 20 eyes of polypoidal choroidal vasculopathy (PCV) were evaluated.

Results

The mean logarithm of the minimum angle of resolution (logMAR) vision of all AMD patients was 0.807 at the baseline examination and 0.937 at the 5 year examination. Mean visual acuity letter score loss is similar between patients with tAMD (−7.25) and with PCV (−5.36) at the month 60 examination. The patients with lesions of classic choroidal neovascularization (CNV) had 10.0 letters loss, but the patients with lesions of occult CNV had only 1.43 letters loss. The number of retreatments peaked in year 1 and declined immediately for patients with tAMD, but patients with PCV had significantly more frequent retreatments in the years 3 and 4 than patients with tAMD (P = 1.48 × 10⁻², 5.96 × 10⁻³, respectively).

Conclusion

Visual outcomes in patients with Japanese patients with AMD treated with PDT after 5-year follow up were worse than that in short-term follow up reported previously. In addition, the difference in visual prognosis between tAMD and PCV was not demonstrated after long-term follow-up.

Montage images of spectral-domain optical coherence tomography in eyes with idiopathic macular holes

PURPOSE

To describe the morphologic and anatomic relationships at the vitreoretinal interface, from the macula into the periphery, in patients with idiopathic macular hole. Montaged images of posterior and peripheral spectral-domain (SD) optical coherence tomography (OCT) studies were used to describe the anatomic vitreoretinal relationships.

DESIGN

Prospective, consecutive, observational case series.

PARTICIPANTS

Forty-six eyes of thirty-six consecutive patients with idiopathic macular hole and their fellow eyes.

METHODS

Montage images of 4 radial OCT scans (horizontal, vertical, and 2 oblique scans) through the fovea were obtained in each case.

MAIN OUTCOME MEASURES

Montage SD OCT images.

RESULTS

In fellow eyes, potential precursor changes to macular hole revealed shallow perifoveal vitreous separation that extends peripherally toward the equator. Two distinct configurations were noted at the posterior vitreous face; eyes without holes had a smooth curvature, whereas eyes with holes were more likely to have wavy, folded, or scalloped vitreous surfaces. At the onset of separation, most posterior vitreous cortex had a smooth curvature, but posterior vitreous folds increased with progressive separation. Also notable were zones of double-layered retinoschisis in regions of adherent posterior vitreous. Resulting granular hyperreflection in the peripheral vitreous was detectable in 50% to 60% of stage 1 or 2 holes but in only 33% of stage 3 or 4 holes.

CONCLUSIONS

The SD OCT montages taken at serial stages of idiopathic macular holes document distinct configurations of the posterior vitreous face, granular hyperreflection in the peripheral vitreous, and areas of peripheral retinoschisis. Montaging SD OCT images provides novel cross-sectional images of the vitreoretinal interface that may have broader application.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Association of elastin gene polymorphism to age-related macular degeneration and polypoidal choroidal vasculopathy

PURPOSE

To see if there is an association in Japanese between elastin gene (ELN) polymorphisms and neovascular age-related macular degeneration (AMD) or its subtypes, typical AMD (tAMD) and polypoidal choroidal vasculopathy (PCV).

METHODS

The authors genotyped five single nucleotide polymorphisms (SNPs), rs2301995, rs2856728, rs868005, rs884843, and rs13239907, at Kyoto University and Saitama Medical University. A case-control study was performed on 1296 patients with AMD and 478 controls.

RESULTS

A statistically significant association was detected between the rs2301995 SNP and AMD (P = 0.018). Furthermore, subtype analysis revealed a significant association of rs2301995 with tAMD (P = 0.0018), but not with PCV. The genotype distribution of rs2301995 also differed significantly between tAMD and PCV (P = 0.00030). The trend in genotype distribution of rs2301995 was similar between the Kyoto and the Saitama studies. The A allele frequency was higher in tAMD, whereas it was similar in PCV and in controls, which is opposite to that reported in a previous study that the A allele frequency is higher in PCV, whereas it is similar in tAMD and in controls. Haplotype analysis also showed that the ELN polymorphism is significantly associated with tAMD (P = 0.0055), but not with PCV.

CONCLUSIONS

ELN is associated with AMD in Japanese. Furthermore, the findings suggest that ELN is a susceptibility gene for tAMD but not for PCV, which is opposite to that reported in a previous study that ELN is the susceptibility gene for PCV but not for tAMD.

Complement factor H and high-temperature requirement A-1 genotypes and treatment response of age-related macular degeneration

PURPOSE

To determine whether there is an association between complement factor H (CFH), high-temperature requirement A-1 (HTRA1), vascular endothelial growth factor (VEGF), and pigment epithelium-derived factor (PEDF) genotypes and response to treatment with photodynamic therapy (PDT) for age-related macular degeneration (AMD) in a Japanese population.

DESIGN

Prospective, case-control study.

PARTICIPANTS

One hundred ten patients with exudative AMD treated by verteporfin PDT were recruited prospectively at the Department of Ophthalmology, Saitama Medical University Hospital, Saitama, Japan.

METHODS

The patients were genotyped for 4 single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996, rs2274700) in the CFH gene, a rs11200638-SNP in the HTRA1 gene, 3 SNPs (rs699947, rs1570360, rs2010963) in the VEGF gene, and 4 SNPs (rs12150053, rs12948385, rs9913583, rs1136287) in the PEDF gene using a TaqMan assay.

MAIN OUTCOME MEASURES

The treatment outcomes and genotypes of CFH, HTRA1, VEGF, and PEDF polymorphisms.

RESULTS

Best-corrected visual acuity 1 year after PDT was significantly increased in patients with the HTRA1-rs11200638 GG genotype as compared with patients with the GA or AA genotypes (P = 2.9 × 10⁻², 7.0 × 10⁻⁴, respectively). The rate of recurrence in the 12-month period after PDT was also associated with HTRA1-rs11200638 genotype (P = 3.12 × 10⁻²). Patients with the AA genotype of HTRA1-rs11200638 had an approximately 6-fold greater risk of the recurrence than patients with the GG genotype (P = 5.58 × 10⁻³). Significant differences were demonstrated in the mean time interval from the initial treatment to the time of recurrence for the genotypes of CFH-rs1410996/-rs2274700 (P = 8.50 × 10⁻³).

CONCLUSIONS

The HTRA1-rs11200638 and CFH-rs1410996/-rs2274700 variants were associated with response to PDT in this study population. These variants may be used for genetic biomarkers to estimate visual outcomes and recurrences in the response to PDT with significant predictive power.

CFH, VEGF, and PEDF genotypes and the response to intravitreous injection of bevacizumab for the treatment of age-related macular degeneration

We determined whether there is an association between complement factor H (CFH), high-temperature requirement A-1 (HTRA1), vascular endothelial growth factor (VEGF), and pigment epithelium-derived factor (PEDF) genotypes and the response to treatment with a single intravitreous injection of bevacizumab for age-related macular degeneration (AMD). Eighty-three patients with exudative AMD treated by bevacizumab injection were genotyped for three single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996) in the CFH gene, a rs11200638-SNP in the HTRA1 gene, three SNPs (rs699947, rs1570360, rs2010963) in the VEGF gene, and four SNPs (rs12150053, rs12948385, rs9913583, rs1136287) in the PEDF gene using a TaqMan assay. The CT genotype (heterozygous) of CFH-rs1061170 was more frequently represented in nonresponders in vision than TT genotypes (nonrisk allele homozygous) at the time points of 1 and 3 months, while there was no CC genotype (risk allele homozygous) in our study cohort (p = 7.66 × 10(-3), 7.83 × 10(-3), respectively). VEGF-rs699947 was also associated with vision changes at 1 month and PEDF-rs1136287 at 3 months (p = 5.11 × 10(-3), 2.05 × 10(-2), respectively). These variants may be utilized for genetic biomarkers to estimate visual outcomes in the response to intravitreal bevacizumab treatment for AMD.

Phenotype and genotype characteristics of age-related macular degeneration in a Japanese population

PURPOSE

To describe phenotype and genotype characteristics of age-related macular degeneration (AMD) in Japanese patients.

DESIGN

A case-control study.

PARTICIPANTS

A total of 550 case-control samples composed of 408 consecutive AMD cases and 142 controls.

METHODS

Clinical information assessing age, gender, affected eyes, fundus features, and fluorescein/indocyanine green angiograms were systematically evaluated. Four single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996, rs2274700) in the complement factor H (CFH) gene, 1 SNP (rs11200638) in the high-temperature requirement factor A1 (HTRA1) gene, 3 SNPs (rs699947, rs1570360, rs2010963) in the vascular endothelial growth factor (VEGF) gene, and 4 SNPs (rs12150053, rs12948385, rs9913583, rs1136287) in the pigment epithelium-derived factor (PEDF) gene were assessed using TaqMan technology.

MAIN OUTCOME MEASURES

The clinical phenotype information and genotypes of CFH, HTRA1, VEGF, and PEDF polymorphisms.

RESULTS

Of Japanese patients with neovascular AMD (nAMD), 219 (58.7%) had typical nAMD and 154 (41.3%) had polypoidal choroidal vasculopathy (PCV). The frequency of bilateral exudative involvement was similar between typical nAMD (15.5%) and PCV (13.6%) (P = 0.613). Significant soft drusen were observed in the fellow eyes of 88 (47.6%) of 185 patients with unilateral typical nAMD and in 25 (18.8%) of 133 patients with unilateral PCV (P = 1.24x10(-7)). A serous pigment epithelium detachment was seen in 55 (25.1%) of 219 patients with typical nAMD and in 64 (41.6%) of 154 patients with PCV. A significant association was noted in CFH-rs800292, CFH-rs1410996, CFH-rs2274700, and HTRA1-rs11200638 with AMD development (P = 2.36x10(-5), 7.18x10(-5), 7.18x10(-5), 2.70x10(-7), respectively; population attributable risk = 57.3%, 57.8%, 57.8%, and 58.9%, respectively). We estimated the highest-risk group to have an approximately 70-fold greater risk of nAMD compared with the lowest-risk group when analyzing a combination of 4 SNPs in the CFH and HTRA1 genes.

CONCLUSIONS

The Japanese AMD phenotype is characterized by a higher frequency of PCV, male predominance, and lower frequency of bilateral presentation compared with Caucasian AMD. Genotype analyses demonstrate a significant population attributable risk for SNPs in the CFH and HTRA1 genes and demonstrate joint effects for both genes. Gene variants in both CFH and HTRA1 contribute significantly to the AMD phenotype in a Japanese population.

[Outcome of photodynamic therapy for exudative age-related macular degeneration with good visual acuity]

PURPOSE

To evaluate visual outcome one year after photodynamic therapy (PDT) in patients with exudative age-related macular degeneration (AMD) showing good visual acuity (VA).

SUBJECTS AND METHODS

One hundred and thirteen patients with AMD who received PDT therapy were recruited for this study. The study subjects were divided into two groups : those having a better visual acuity than 0.6 (n = 34), and those with VA worse than 0.5 (n = 79). All patients were examined by corrected visual acuity, fundus biomicroscopy, and optical coherence tomography (OCT) before, 1 month, 3 months, and 12 months after PDT.

RESULTS

Visual acuity at 12 months was either at baseline visual acuity or improved in 82% of the better vision group. Foveal retinal thickness was significantly reduced with PDT in both the better vision and the worse vision groups (p = 0.04, 0.008, respectively). The greatest linear dimension (GLD) was significantly associated with significant vision decline among baseline factors (p = 0.049)such as gender and age.

CONCLUSIONS

PDT is an effective adjunct for AMD patients even when they have good baseline vision. To perform PDT safely for AMD in patients with good vision, both larger GLD and retinal pigment epithelial detachment have to be considered as a risk factor.

Coding and noncoding variants in the CFH gene and cigarette smoking influence the risk of age-related macular degeneration in a Japanese population

PURPOSE

Ethnic variation has been reported in age-related macular degeneration (AMD)-associated Y402H polymorphism in complement factor H (CFH). This variation is evident in the Japanese population. Recently a strong association between a novel single-nucleotide polymorphism (SNP; rs1410996) in the CFH gene and AMD has been identified in Caucasian patients. The present study was undertaken to investigate whether four coding and noncoding variants of the CFH gene, including rs1410996, are associated with AMD in native, unrelated Japanese patients.

METHODS

A total of 188 patients with AMD and 139 control subjects without AMD were recruited for the study. Four SNPs (rs800292, rs1061170, rs1410996, and rs2274700) in the CFH gene were assessed by genotyping assay. The information regarding systemic conditions and lifestyle including smoking were documented in each subject by standardized questionnaire.

RESULTS

The intronic SNP (rs1410996) and the synonymous SNP (rs2274700) were associated with a significant risk of AMD (P = 2.37 x 10(-5) and 3.52 x 10(-5), respectively). A significant association was also noted between a coding variant (rs800292, I62V) and AMD (P = 8.63 x 10(-6)). In contrast, the Y402H variant showed no significant association with AMD (P = 0.101). Two common haplotypes also demonstrated significant association with AMD (P = 1.08 x 10(-3) and 2.00 x 10(-5)). Among the environmental factors, smoking alone had a significant association with AMD (P = 1.17 x 10(-4)).

CONCLUSIONS

Although the Y402H variant was not significantly associated with AMD, other coding and noncoding variants in the CFH gene including rs1410996 and smoking moderately influenced the risk of AMD in a Japanese population.

Promoter polymorphisms of the pigment epithelium-derived factor gene are associated with diabetic retinopathy

Pigment epithelium-derived factor (PEDF or SERPINF1), a neuroprotective and anti-angiogenic factor, may play an important role in the pathogenesis of diabetic retinopathy (DR). In 416 patients with type 2 diabetes, four polymorphisms in the PEDF SNPs were identified, rs12150053 and rs12948385 in the promoter region, rs9913583 in the 5'-untranslated region, and rs1136287 (Met72Thr) in exon 3. Based on case-control studies, rs12150053 and rs12948385, but not rs9913583 and rs1136287, were significantly associated with DR. A logistic regression analysis revealed that the TC or CC genotype of rs12150053 was a significant risk factor for DR (odds ratio 2.40, p=0.0004). The GA or AA genotype of rs12948385 was also a significant risk factor for DR. In addition, a significant interaction between the vascular endothelial growth factor (VEGF) and PEDF SNPs in the susceptibility to DR was found. These results demonstrate that the PEDF gene, in cooperation with the VEGF gene, may contribute to the development of DR.

Association of the HTRA1 gene variant with age-related macular degeneration in the Japanese population

The purpose of this investigation was to determine whether the high-temperature requirement A-1 (HTRA1) gene polymorphism is associated with age-related macular degeneration (AMD) in native, unrelated Japanese patients. A total of 123 patients with AMD and 133 control subjects without AMD were recruited for this study. The single-nucleotide polymorphism (SNP) rs11200638 in the HTRA1 gene was assessed using a TaqMan assay. The risk A allele frequencies in the AMD cases and control patients were 0.577 and 0.380, respectively, and were associated with a significant risk of developing AMD (p=7.75x10(-6)). The results were more significant in subtype analyses with wet AMD (p=5.96x10(-7)). We conclude that the rs11200638 variant in the HTRA1 gene is strongly associated with AMD in the Japanese population. This result supports the hypothesis that the HTRA1 gene may increase susceptibility to AMD development and can participate in a potential new molecular pathway for AMD pathogenesis by extending this association across diverse ethnicities.

[Case of corneally displaced malignant conjunctival melanoma]

BACKGROUND

We studied the clinicopathologic characteristics in a patient with malignant conjunctival melanoma associated with corneal invasion.

CASE

A 62-year-old man had a small melanocytic lesion of the inferior palpebral conjunctiva. Previously he had undergone excisional biopsy and was diagnosed as having melanocytic hyperplasia without cytological atypia at an other hospital. He developed recurrence and was referred to us. The pigmentary lesion was observed in the entire inferior palpebral conjunctiva. Biomicroscopic examination revealed that there was a granular pigment lesion in the cornea. The patient was diagnosed as having conjunctival melanoma with corneal invasion and treated with orbital exenteration and chemotherapy in our hospital. Clinicopathologic tests revealed malignant melanoma cells invading through the bulbar conjunctiva and into the cornea. Ultrastructural study by electron microscopy of the pigmented tumor cells in the cornea showed several lobations of the nuclei, a large active-appearing nucleolus, and an aberrant granular melanosomal morphology.

CONCLUSIONS

The infiltration of palpebral malignant conjunctival melanoma was limited to the epidermis of the cornea.

Intraocular Biodistribution of Mono-L-aspartyl Chlorin e6 in a Primate Choroidal Neovascularization Model

BACKGROUND AND OBJECTIVE

To describe the biodistribution of a hydrophilic sensitizer, mono-L-aspartyl chlorin e6 (NPe6), in a primate model of choroidal neovascularization (CNV).

MATERIALS AND METHODS

NPe6 (25 mg/kg) and indocyanine green (ICG, 15 mg/kg) were intravenously administered simultaneously in monkeys with laser-induced CNVs. Eyes were enucleated and examined by fluorescence microscopy immediately, 20 minutes, and 1, 4, and 24 hours after dye injection.

RESULTS

Fluorescence peaked in retinal vessels immediately after dye administration; rapid washout began 1 hour postinjection. In contrast, experimental CNV demonstrated little fluorescence immediately after injection, with increased intensity at later time points. Peak dye fluorescence in CNV occurred 1 hour following dye injection. NPe6 fluorescence diminished rapidly and washed out completely by 24 hours. The dye accumulation and retention pattern of ICG dye resembled that of NPe6.

CONCLUSIONS

This study demonstrated the selective accumulation of NPe6 photosensitizer and ICG dye within experimental CNV and rapid clearance from the circulation and retinochoroidal tissue.

Treatment of stage 2 macular hole by intravitreous injection of expansile gas and induction of posterior vitreous detachment

PURPOSE

To demonstrate the morphological and functional outcomes of intravitreous injection of an expansile gas bubble for the treatment of stage 2 macular holes.

DESIGN

Prospective interventional case series.

PARTICIPANTS

Twenty eyes of 20 consecutive patients with unilateral stage 2 macular holes.

METHODS

The patients underwent intravitreous sulfur hexafluoride injection, followed by postoperative facedown positioning for 3 to 5 days. The patients were observed per protocol schedule with complete ophthalmological examination, including determination of corrected visual acuity (VA), slit-lamp biomicroscopic examination, funduscopic examination, and optical coherence tomography (OCT). Follow-up was greater than 12 months for all patients (mean, 19.5).

MAIN OUTCOME MEASURES

Posterior vitreous detachment, anatomical closure of the hole, VA, and hole diameter as measured by OCT.

RESULTS

Detachment of the posterior vitreous at the macula was achieved in 19 of 20 eyes (95%). Ten cases (50%) had anatomical closure of the hole with intravitreous gas injection alone. The remaining 10 cases (50%) achieved anatomical closure of the hole after subsequent vitreous surgery. There was a significant difference in hole diameter (P = 0.004) and in pretreatment vision (P = 4.5x10(-5)) in patients for whom gas alone resulted in hole closure and those proceeding to vitreous surgery. Hole closure by gas injection alone was achieved in 7 of 7 eyes (100%) with pretreatment vision better than 20/40 and in 6 of 7 eyes (86%) when the hole was smaller than 200 mum. There were no major complications in this series of patients. Successfully treated macular holes remained closed at all follow-up points during the study period.

CONCLUSION

An intravitreous injection of an expansile concentration of the inert sulfur hexafluoride gas alone frequently induces detachment of the posterior vitreous in the aged eye. Anatomical closure of the hole without major complications is more likely in smaller holes with better pretreatment vision. This technique may have clinical application for stage 2 holes in selected cases. A number of potential advantages including decreased morbidity and a potential cost savings may result from successful utilization of this procedure.

Transpupillary thermotherapy-induced modification of angiogenesis- and coagulation-related gene expression in the rat posterior fundus

PURPOSE

To study gene expression changes in the rat retina and choroid following transpupillary thermotherapy (TTT) and to identify molecular mechanisms that may enhance treatment of choroidal neovascularization, complicating age-related macular degeneration.

METHODS

One fundus of Brown Norway rats was treated with an 810 nm diode laser while the contralateral fundus received no treatment. The mRNA was extracted and processed for cDNA microarray analysis. Genes with increased expression were validated by semiquantitative reverse transcription polymerase chain reaction (PCR) and quantitative real-time PCR (qRT-PCR).

RESULTS

Of the 14,815 cDNA elements on the array, 12 genes were up-regulated in TTT treated eyes. Upregulation of eight of these 12 genes could be verified by semiquantitative RT-PCR. The eight verified genes were EPCR, IL-1beta, MCP-1, TSP-1, Fgl, Asns, MT-2, and NMDMC, which included 4 angiogenesis- and coagulation-related genes.

CONCLUSIONS

This study demonstrates upregulation of angiogenesis- and coagulation-related genes following TTT. The response profile and its temporal relationships provide insight into the molecular mechanisms that lead to vascular occlusion and antiangiogenesis induced by TTT.

Bilateral Optic Neuropathy Associated with Multiple Myeloma

A 51-year-old man had reduced vision and bilateral optic disc swelling as the initial clinical manifestation of multiple myeloma. Brain imaging failed to disclose any abnormalities. Before any therapy was begun, visual function began to improve substantially. Three months after chemotherapy was started, visual function and optic disc appearance returned to near normal. There were no features to suggest polyneuropathy-organomegaly-endocrinopathy-M protein-skin changes (POEMS) syndrome. Visual loss in myeloma is usually caused by compression or infiltration of the optic nerves by tumor. The mechanism of the optic neuropathy in this case remains unknown.

[Ultra-late phase of indocyanine green angiography in a case with metastatic choroidal tumor]

PURPOSE

To report a case with metastatic choroidal tumor evaluated with ultra-late phase of indocyanine green (ICG) angiography.

CASES

A 43-year-old woman had metastatic choroidal tumor originating from the thymus with an associated serous retinal detachment. ICG video-angiography demonstrated the tumor as hypofluorescent during the arterio-venous phase and hyperfluorescent during the conventional late phase (about 30 minutes after dye injection), and in the ultra-late phase (24 hours after dye injection). The original and metastatic tumors were treated by radiotherapy, resulting in flattening of the choroidal tumor and resolution of the serous retinal detachment. After the treatment, ICG angiography showed decay of ICG fluorescence and no apparent late accumulation of residual ICG in the tumor.

CONCLUSION

In a case with metastatic choroidal tumor, ICG dye accumulated in the tumor tissue before the treatment, but it decreased after treatment. This finding suggested that dye accumulation may be correlated with the tumor activity and requires a further study, enrolling patients with metastatic choroidal tumor for ICG angiographic evaluation.

[Melanoma-associated retinopathy with unknown primary site in a Japanese woman]

BACKGROUND

We report the clinical features of the first case of a Japanese person with melanoma-associated retinopathy.

CASE

A 44-year-old woman complained of photopsia and blurred vision in her right eye, and was treated with steroids for uveitis by an ophthalmologist. She was referred to our hospital for further examination. After one month of treatment, she still complained of photopsia in her right eye. The best corrected visual acuity in the right eye was 0.8 and these was sensitivity loss in the central visual field test. Ophthalmoscopy and fluorescein angiography showed some retinal vasculitis in the right eye. A full-field electroretinogram demonstrated a negative-type electroretinogram (ERG) waveform with attenuation of the b-wave amplitude in the right eye. A dark adaptation test revealed sensitivity loss of the rods. The lymph nodes on the right side of her neck were examined and the diagnosis was made of metastic cutaneous melanoma with unknown primary site; her visual dysfunction was diagnosed as melanoma-associated retinopathy. The retinal inflammation improved after steroid treatment, but her visual dysfunction remained. Chemotherapy and an immunotherapy regimen was begun, but 36 months later she died of metastatic melanoma in the lungs.

CONCLUSIONS

A woman treated for uveitis without any prior systemic and ocular diseases was diagnosed with melanoma-associated retinopathy and metastatic melanoma in the cervical lymph nodes of unknown primary origin. The first ocular symptoms were photopsia and blurred vision, not night blindness. ERG was useful for diagnosing this rare ocular condition in an early stage.

TRANSPUPILLARY THERMOTHERAPY

PURPOSE

To correlate changes in primate fundus after transpupillary thermotherapy (TTT) at two wavelengths.

METHODS

Twelve primate eyes were treated with TTT using a wavelength of 635 nm (n=7) or 810 nm (n=5). Laser parameters were as follows: 635 nm (spot size, 1 mm; duration, 30-8 seconds; and fluence [power over time], 20-91.4 J/cm) and 810 nm (spot size, 2 mm; duration, 60 seconds; and fluence, 96-436 J/cm). Fundus photography, fluorescein and indocyanine green angiography, and enucleation were performed at time 0 or 2 weeks after TTT for histologic analysis.

RESULTS

Threshold for fundus lesions (91.4 J/cm at 635 nm and 191 J/cm at 810 nm), acute and chronic retinal damage shown by histologic analysis (79.2 J/cm at 635 nm and 96 J/cm at 810 nm), and choroidal vessel occlusion (50 J/cm at 635 nm and 96 J/cm at 810 nm) were lower at 635 nm. Disorganization of the retina and retinal pigment epithelium was seen for both wavelengths at time 0 and 2 weeks after TTT. Occlusion of the choriocapillaris and choroidal stromal vessels was noted only in specimens obtained 2 weeks after TTT.

CONCLUSIONS

TTT resulted in acute and delayed damage to the neurosensory retina that persisted at 2 weeks. The 635-nm wavelength demonstrated a lower threshold fluence for visible fundus lesions, retinal damage, and choroidal vascular occlusion than the 810-nm laser.

Laser Photocoagulation and, to a Lesser Extent, Photodynamic Therapy Target and Enhance Adenovirus Vector–Mediated Gene Transfer in the Rat Retina

PURPOSE

To evaluate the transduction efficiency and localization of a reporter gene after intravitreous injection of adenovirus vector in laser photocoagulation (PC)- and photodynamic therapy (PDT)-treated eyes.

METHODS

Adult Lewis rats received fundus PC, fundus PDT, or no treatment. Intravitreous injection of an adenovirus vector containing the construct expressing beta-galactosidase (AdlacZ.11D) was performed in each group. All eyes were then enucleated for histochemistry and processed for quantitative image analysis.

RESULTS

In eyes with no treatment, there was moderate to intense staining for lacZ in the anterior segment, but little in the retina. In eyes treated with PC and PDT, there was significantly more LacZ staining in the retina. The increased staining corresponded closely with the sites treated with PC and PDT. Gene transduction in PC-treated eyes was enhanced and extended to at least 135 days after virus delivery, but not extended in PDT-treated eyes. Gene transfer and expression were targeted and enhanced at the site of laser burns, at all doses tested (3 x 10(5) to 3 x 10(9) particles per eye).

CONCLUSIONS

Compared with untreated eyes, eyes treated with PC and to a lesser extent PDT, manifest increased transduction efficiency, in areas of the retina that are targeted by laser treatment. This finding suggests a new and promising strategy for the treatment of retinochoroidal neovascularization. Adenovirus gene therapy in combination with PC or PDT would have the advantage of increased transduction efficiency; increased duration of transgene expression; targeted delivery; and, potentially, a lower effective dose of virus.

Functional VEGF C-634G polymorphism is associated with development of diabetic macular edema and correlated with macular retinal thickness in type 2 diabetes

Since vascular endothelial growth factor (VEGF) has a strong effect on induction of vascular permeability, VEGF is an attractive candidate gene for development of diabetic macular edema (ME). Among the 378 patients with type 2 diabetes studied, 203 patients had no retinopathy, 93 had non-proliferative diabetic retinopathy (NPDR), and 82 had proliferative diabetic retinopathy (PDR). ME was present in 16 patients with NPDR and 47 patients with PDR. We genotyped three VEGF polymorphisms: C-2,578A, G-1,154A, and C-634G. Genotype and allele distribution of C-634G, but not C-2,578A or G-1,154A, were significantly different between patients with and without diabetic retinopathy. Logistic regression analysis revealed that the C-634G genotype was a risk factor for DR (p = 0.002), and furthermore for ME (p = 0.047), independently from severity of DR, with the -634C allele increasing the risk. Macular thickness measured by optical coherence tomography was correlated with the C-634G genotype, with the trend increasing with the presence of more -634C alleles (p = 0.006). Stepwise regression analysis showed that duration of diabetes and presence of the C-634G genotype were independent predictors of macular thickness. In addition, basic transcriptional activity levels associated with the -634C allele were greater compared to those seen with the -634G allele in human glioma and lymphoblastic T-lymphocyte cells. These results demonstrate that the VEGF C-634G polymorphism is a genetic risk factor for ME as well as DR.

DECREASED ARTERIAL DYE-FILLING AND VENOUS DILATION IN THE MACULAR CHOROID ASSOCIATED WITH AGE-RELATED MACULAR DEGENERATION

PURPOSE

To compare the angioarchitecture of choroidal arteries and veins in patients with age-related macular degeneration (AMD) to the angioarchitecture of age-matched normal subjects using indocyanine green (ICG) angiography.

METHODS

ICG angiography was performed in 35 consecutive AMD patients and 18 normal age-matched volunteers with a fundus ICG camera. ICG video images, including the arterial and venous phases, were quantitatively analyzed using image analyzing software.

RESULTS

In patients with AMD, the choroidal arterioles are dilated, fewer, run a straighter course, and possess fewer bifurcations. The number of choroidal arteries and the macular fluorescent intensity in the arterial phase of choroidal filling was significantly less in patients with AMD as compared to age-matched normal controls (P = 0.008). The mean and maximum caliber of choroidal veins in the macula was dilated in AMD eyes than in age-matched normal control eyes (P < 0.001). There was no statistically significant difference in arterial dye filling or venous caliber observed in AMD eyes, with or without choroidal neovascular membrane (CNV).

CONCLUSION

Choroidal arterial perfusion in the macula was significant decreased in eyes with AMD with and without CNV, and was associated with choroidal venous dilation. These observations implicate poor choroidal perfusion of the macula in the pathogenesis of AMD.

Midperipheral mottling pigmentation with familial choroidal osteoma

PURPOSE

To describe a rare presentation of familial choroidal osteoma in two siblings.

METHODS

The clinical findings in two siblings over 4 years' follow-up.

RESULTS

Two brothers (15 and 12 years old) had bilateral choroidal osteomas. Both had bilateral peripapillary yellowish-white lesions and midperipheral mottling pigment appearance, which are not seen in sporadic cases. Extensive midperipheral area with mottling pigment appearance was noted by fluorescein angiography (FA) as scattered multiple hyperfluorescent dots. The yellowish-white lesions showed diffuse hyperfluorescence with FA and hypofluorescence with indocyanine green angiography (ICG). ICG also revealed irregular hyperfluorescent areas within the tumor, indicating abnormal choroidal vessels on the tumor. In the left eye of the younger brother, the subretinal fibrosis due to choroidal neovascularization superior to the macula extended down toward the foveal region over 2 years, resulting in visual deterioration.

CONCLUSION

The midperipheral mottling pigment appearance of familial choroidal osteoma cases is unique and different from most sporadic cases, suggesting that familial choroidal osteoma might have separate etiologic or modified factors.

[A new approach for studying the retinal and choroidal circulation]

One advantage of advanced computer technology is the high throughput with which the retinal and the choroidal circulation can be evaluated from new aspects. To study the choroidal circulation, we first reevaluated indocyanine green video angiography to improve the visualization of indocyanine green (ICG) images, then applied computer technology to analyze images obtained by an ICG video camera system. We also developed a new instrument to measure oxygen saturation levels in the fundus using spectral retinal imaging technology. I. Choroidal circulation. 1. Reevaluation of ICG video camera system: For this purpose, the bio-chemical nature of ICG was studied. 1) Spectral absorption of ICG: The peak absorption of ICG in distilled water was 780 nm as measured with a spectrophotometer. Its maximum absorption shifted from 780 nm to 805 nm after gradually mixing ICG with human serum protein. Conjugation time of ICG as well as fluorescein sodium with human serum protein was then measured by a stopped flowmeter. It was found that fluorescein sodium conjugated with human serum protein within a few milliseconds, while ICG required more than 600 seconds before equilibrium of the binding was reached. From these observations, we developed a new ICG video system with dual light sources; one, a 780 nm diode laser for the early dye filling phase, and the other, a 805 nm diode laser for the later phase of ICG angiography. 2) Binding properties of ICG in human blood: Blood samples were obtained from three healthy volunteers after intravenous administration of ICG. The resulting plasma samples were fractionated by agarose gel immunoelectrophoresis and polyacrylamide gel DISC electrophoresis. The electrophoretic pattern obtained by each method was observed with an ICG fundus video system. We also studied the affinity of ICG for lipids that are common molecular components of lipoproteins such as high-density lipoprotein (HDL) and low-density lipoprotein (LDL). Four kinds of ICG solutions mixed with phospholipid, free cholesterol, esterified cholesterol, and triacrylglycerol were observed with the ICG fundus video system. Both electrophoretic studies showed that ICG bound intensely to HDL and moderately to LDL, and only the solution with phospholipid fluoresced brightly when observed with the ICG fundus video system. 2. Residual fundus ICG fluorescence: Residual fundus fluorescence observed in the late phase of ICG angiography may be delineated differently in normal subjects and in patients with age-related macular degeneration (ARMD). We performed ICG angiography on 8 normal subjects aged below 36 years (8 eyes), 9 normal subjects aged above 62 years (9 eyes), and 21 patients with ARMD aged 50 to 88 years (37 eyes). The intensity and pattern of fluorescence from angiograms obtained in the ultra-late phase, 24 hours after dye injection, was recorded and analyzed. In the ultra-late phase, 95% of ARMD eyes with choroidal neovascularization (CNV) showed geographic hypofluorescent lesions. These hypofluorescent lesions occurred in 73% of ARMD eyes without CN, while age-matched normal subjects had no hypofluorescent lesions. The mean intensity of fluorescence in the normal elder subject group was significantly higher than that seen in the normal younger subject group. These findings may reflect aging change and bio-distribution of lipid on the Bruch-RPE complex. 3. The early dye filling pattern of the choroid: We performed ICG angiography on 10 healthy young volunteers aged 22 to 26 years (23.4+/-1.3; mean+/-standard deviation) using an improved ICG video camera system. ICG (50 mg) dissolved in 2 ml in distilled water was injected through the antecubital vein. Although the choroidal dye filling varied among subjects, it always began in the macular area. In the 10 subjects, initial dye filling had two patterns: reticular (n=8) and flush (n=2). The choroidal circulation filled completely before the retinal circulation did. Bright fluorescence in the macula and fast blood flow may be correlated with ample blood volume and abundant blood vessels in the macular area. 4. The spreading pattern of ICG fluorescence in the choroid: The ICG images obtained for observing the early dye filling pattern of the choroid were further processed with a computer-assisted image analyzer. Subtracted images were made using the early ICG frames with a time interval of 0.12 second. Ninety frames of time-sequential images for 3 seconds starting from the initial dye appearance in the choroid were prepared to construct an animated image. In the initial phase of eye filling, patchy fluorescence appeared in the fovea. The fluorescence then spread centrifugally in all directions in a wave-like pulsatile manner towards the peripheral fundus with increasing brightness. Thus an animated video of subtracted images allowed us to evaluate flow dynamics at the level of the choriocapillaris. Using this new approach, pathogenic involvement of choroidal circulation in varied chorioretinal diseases such as central serous chorioretinopathy can be studied with precision. II. Retinal circulation. We developed a new device to study the oxygen saturation (OS) levels in a wider fundus area. We call this device a spectral retinal image (SRI) system. We are pursuing the possibility of this instrument being in clinics to evaluate chorioretinal diseases. 1. Introduction of the device: The instrument consists of a Sagnac interferometer that has been mounted on top of a fundus camera, and a software module which consists of an acquisition module and an analysis module. The image acquisition process takes 6 seconds during which the fundus is illuminated by the white incandescent light of the fundus camera at the regular power settings. OS values in each pixel of the fundus image with a 35-degree view can then be estimated from the respective spectrum that is obtained by Fourier-transforming the interferometer signals. Each OS value is represented by a specific color, and each pixel of the fundus image is painted accordingly. 2. Clinical applications. 1) Control study: OS levels of both retinal arteries and veins within a 1 disc diameter (DD) area around the disc were measured from 20 SRIs obtained from 10 healthy volunteers, and were 96.65+/-3.30% and 56.05+/-4.69%, respectively. Then 30 healthy volunteers were recruited for further study in which the OS values were calculated in five retinal regions: (1) juxta-papillary area within 1.75 DD, (2) fovea within 1.0 DD, (3) papillomacular region within 1.0 DD, (4) superior area of the posterior fundus within 1.0 DD, and (5) inferior posterior area of the posterior fundus within 1.0 DD. The OS level of the juxta-papillary area was the highest, while that of the fovea was the lowest and the other three posterior retinal regions were in the middle. Thus OS levels differed at various areas in the retina with statistical significance. In spite of abundant choroidal circulation in the fovea, the overlying retina may have a relative by low oxygen level. As the retinal pigment epithelium may be efficient enough to block the effect of the choroid optically, our results may indicate that the OS levels represent the OS of the retina. 2) Measurement of OS levels in eyes with retinal circulatory disturbances: Eleven eyes of 10 patients with central retinal vein occlusion (CRVO), which showed various degrees of severity, and 4 fellow unaffected eyes of selected patients were examined by both fluorescein angiography (FAG) and the new SRI system. The fluroescein angiograms were correlated with OS maps that were calculated from the SRI. OS grading demonstrated by OS maps correlated well with severity of CRVO, as estimated by FAG. Thus our SRI system is noninvasive with reproducible results, and may prove to be a useful clinical tool to evaluate the degree of retinal ischemia. 3) Measurement of OS levels in eyes with glaucoma: Forty-seven eyes with open angle glaucoma (OAG) of 47 patients and 21 eyes of 21 age-matched normal subjects were recuited for the study. Twelve eyes with low-tension glaucoma (LTG) were included in the OAG eyes and the rest of the OAG eyes had primary OAG. All patients and normal subjects were examined by SRI. Visual field tests for OAG eyes were done with a Humphrey Field Analyzer using the 30-2 program, Swedish interactive threshold argorithm (SITA). OS levels in the retina at 5 different points: superior, inferior, superio- and inferio-temporal, and nasal region within a juxta-papillary area of 200 microm in diameter were calculated from the SRI. OS levels of retinal arteries were also measured and there were no significant differences between OAG and the control group. OAG eyes showed reduced OS levels in the inferio-temporal retina with statistical significance. This observation was more prominent in LTG eyes. The reduced OS levels observed in OAG eyes correlated well with mean deviation (MD) and the sum of total deviation of the 17 points in corresponding areas in the visual field analysis.

Endothelial nitric oxide synthase gene is associated with diabetic macular edema in type 2 diabetes

OBJECTIVE

We examined the endothelial nitric oxide (eNOS) gene polymorphisms to assess its possible association with diabetic retinopathy and macular edema.

RESEARCH DESIGN AND METHODS

A total of 226 patients with type 2 diabetes and 186 healthy subjects were studied. Type 2 diabetic patients consisted of 110 patients without retinopathy, 46 patients with nonproliferative diabetic retinopathy, and 71 patients with proliferative diabetic retinopathy. Diabetic macular edema was present in 48 patients. Three polymorphisms of the eNOS gene were determined: T-786C in the promoter region, 27-bp repeat in intron 4, and Glu298Asp in exon 7.

RESULTS

Close linkage disequilibrium was observed between the T-786C polymorphism and the 27-bp repeat, as has been previously reported, but Glu298Asp was not in linkage disequilibrium with the other two polymorphisms. The eNOS gene polymorphisms were not significantly associated with the presence of retinopathy or with retinopathy severity or type 2 diabetes itself. However, by both association study and multiple logistic regression analysis, the T-786C and 27-bp repeat polymorphisms were significantly associated with a risk of developing macular edema with the -786C allele and the "a" allele increasing the risk.

CONCLUSIONS

The present study suggests that the eNOS gene is a novel genetic risk factor for diabetic macular edema. The eNOS gene polymorphisms may contribute to the development of macular edema by impairing basal eNOS expression and resulting in the breakdown of the blood-retina barrier.

Enhanced documentation of slit-lamp images of the human vitreous stained with fluorescein sodium

BACKGROUND AND OBJECTIVE

To develop a new method to document the slit-lamp image of the vitreous body as stained with fluorescein sodium.

PATIENTS AND METHODS

The system consists of a Goldmann-type slit-lamp biomicroscope, a highly sensitive monochromatic charge-coupled device camera, and a video attachment for real-time observation and recording. As a standard procedure, observation of the vitreous was conducted 60 minutes after intravenous administration of 500 mg of fluorescein sodium. This method was applied to 19 eyes with various eye diseases.

RESULTS

Fine details of the vitreous were observed in all of the eyes. Posterior vitreous detachment could be recorded in 5 of the 19 eyes examined. Vitreoschisis and large lacunae were documented in 11 eyes.

CONCLUSION

This method promises to be of value in detecting early age-related and pathological changes of the vitreous such as posterior vitreous detachment and vitreoschisis in clinics.

Asymmetry of choroidal venous vascular patterns in the human eye

PURPOSE

To describe the angioarchitecture of choroidal veins in normal subjects using indocyanine green (ICG) angiography.

DESIGN

Consecutive observational case series.

PARTICIPANTS

Thirty-six eyes of 33 healthy volunteers ranging in age from 21 to 81 years (50.0+/-18.2 [mean +/- standard deviation]).

METHODS

Indocyanine green angiography was performed with a modified Topcon fundus ICG camera. Montage images were obtained during the venous phase of the ICG angiogram.

MAIN OUTCOME MEASURES

Indocyanine green angiographic montage images covering all areas of the observable fundus.

RESULTS

Eighteen of 36 eyes examined (50%) showed asymmetry of choroidal venous vascular patterns consistent with a preferential route of choroidal venous drainage of the macular region. Twelve of the 18 eyes with a preferred drainage route drained superotemporally; the remaining 6 eyes drained by either an inferotemporal or a superonasal route. A preferential choroidal venous drainage route in the macula was identified with equal frequency in young and old subjects. Of 36 eyes examined, 27 (75%) lacked ICG angiographic evidence of symmetric separation of outer choroidal veins.

CONCLUSIONS

There is ICG angiographic evidence of asymmetry of choroidal venous drainage in one half of normal individuals. The relative frequency of a resulting preferential drainage route in a group of normal subjects and the equal distribution in young and old subjects indicate that this finding is neither pathologic nor attributable to aging. There is also ICG angiographic evidence for a lack of symmetric separation in the outer choroidal venous system in the majority of normal human subjects tested, indicating that classic watershed zones may not be present or are less prominent in this portion of the choroidal vasculature.

COMPARISON OF EPIRETINAL MEMBRANES OF DIFFERING PATHOGENESIS USING OPTICAL COHERENCE TOMOGRAPHY

PURPOSE

To compare optical coherence tomography (OCT) images of idiopathic epiretinal membranes (ERMs) with those of secondary ERMs.

METHODS

OCT was performed on 70 eyes of 63 consecutive patients with biomicroscopic evidence of ERMs and 23 eyes of 23 healthy volunteers without ERMs. OCT findings were correlated with the clinical pathogenesis of the ERM.

RESULTS

Evaluation by OCT established that 48 of 70 ERMs were globally adherent to the retina and that 22 of 70 ERMs were focally adherent to the retina. When correlated to clinical pathogenesis, 20% of idiopathic membranes and 52% of secondary membranes were focally attached to the retina. There was a significant difference in the pattern of membrane attachment to the retina in the two pathogenic groups (P = 0.007). Eight of nine eyes with macular pseudoholes were associated with globally adherent membranes.

CONCLUSION

Secondary ERMs are more likely to be characterized by focal retinal adhesion than are primary ERMs. Primary ERMs tend to be globally adherent. This finding may contribute to understanding the underlying mechanisms of ERM formation in different clinical settings.

Intraocular gene transfer of pigment epithelium-derived factor rescues photoreceptors from light-induced cell death

In this study, we investigated whether intraocular gene transfer of pigment epithelium-derived factor (PEDF) ameliorates the extent of light-induced photoreceptor cell death. Lewis rats received intravitreous injection of 3 x 10(9) particles of adenoviral vector expressing PEDF (AdPEDF.11) in one eye and 3 x 10(9) particles of empty adenoviral vector (AdNull.11) in the contralateral eye. The rats were then dark-adapted for 3 days after which they were continuously exposed to fluorescent light (2,500 lux) for 0, 6, 24, 96, and 168 h. Both eyes were then enucleated and processed for morphometric analysis. Cell death in the retina was examined using TUNEL staining with a propidium iodide counterstain. The photoreceptor cell counts in each of the three groups were significantly different (P < 0.001). Eyes that received intravitreous injection of AdNull.11 or no injection showed a greater number of pyknotic photoreceptor cells and a reduced photoreceptor cell density as compared to eyes treated with intravitreous AdPEDF.11 injection. AdNull.11 treated eyes showed a lesser but still significant protection of photoreceptor cells when compared to untreated eyes. Fewer TUNEL-positive photoreceptor cells were present in AdPEDF.11 treated eyes than in AdNull.11 treated or untreated eyes (P = 0.004). The amplitudes of the ERG a-wave, b-wave, and oscillatory potentials (OPs) were increased significantly by treatment (P < 0.05). These data suggest that adenovirus vector-mediated intraocular expression of PEDF significantly increases photoreceptor cell survival following excessive light exposure. Neuroprotection may result from inhibition of light-induced apoptotic processes. This study provides proof of concept for a gene transfer approach to modulating retinal cell death resulting from photo-oxidative damage and supports the hypothesis that gene transfer of PEDF is broadly applicable to modulating apoptosis in the retina.