Second eye of patients with unilateral neovascular age-related macular degeneration: Caucasians vs Chinese

Multimodal Imaging Comparison of Polypoidal Choroidal Vasculopathy Between Asian and Caucasian Populations

PURPOSE

Differences in multimodal imaging features between Asian and Caucasian eyes may contribute to our understanding of the etiology of the polypoidal choroidal vasculopathy (PCV). The purpose of this study was to compare the multimodal imaging features of Asian and Caucasian eyes with PCV.

DESIGN

Cross-sectional, retrospective, multicenter, observational case series.

METHODS

Consecutive treatment-naïve patients diagnosed with PCV based on indocyanine green angiography in accordance with published guidelines. Demographic and multimodal imaging findings based on color fundus photography, spectral domain optical coherence tomography, fluorescein angiography, and indocyanine green angiography were graded.

RESULTS

A total of 250 participants with PCV (128 Asian vs 122 Caucasian participants) were included. Asian participants presented with lower best-corrected visual acuity (mean ± SD: 0.7 ± 0.6 logMAR vs 0.4 ± 0.3 logMAR; P < .001) compared with Caucasian participants. More Asian eyes had subretinal hemorrhage (mean ± SD: 53.9% vs 24.6%; P < .001) and larger areas of hemorrhage (mean ± SD: 7.5 ± 15.2 mm² vs 1.3 ± 3.3 mm²; P < .001). More Asian eyes had pachyvessels (84.4% vs 28.7%; P < .001), choroidal vascular hyperpermeability (70.3% vs 17.2%; P < .001), and widespread polypoidal lesions (19.5% vs 8.2%; P = .005), and Caucasian eyes had more drusen (79.5% vs 49.2%; P = .02).

CONCLUSIONS

Multimodal imaging analysis revealed ethnic differences in disease characteristics of PCV, suggesting pathophysiologic mechanism of the disease vary based on ethnicity.

Association of Longitudinal Changes in Drusen Characteristics and Retinal Layer Volumes with Subsequent Subtype of Choroidal Neovascularisation

AIM

To investigate the longitudinal correlation between drusen characteristics and retinal layer volumes pre conversion and subsequent type of choroidal neovascularisation (CNV).

METHODS

This was a single-centre retrospective study. The study participants were patients with wet age-related macular degeneration (AMD) in one eye who developed wet AMD in the contralateral eye, with at least 2 years of follow-up prior to conversion. The Moorfields Eye Hospital database was searched for eligible patients and their data were recorded. Eyes were classified as occult or classic based on fundus fluorescein angiography. Optical coherence tomography (OCT) images were analysed for drusen characteristics and retinal layer volumes were analysed over time using automated software (Topcon 3D OCT-2000 and Orion, Voxeleron LLC, respectively). All values were obtained at baseline as well as year 1 and year 2 before conversion to wet AMD.

RESULTS

Fifty-one eyes with bilateral CNV showed high correlation of type of CNV between eyes (kappa statistic 0.89). A total of 49 wet AMD eyes (29 occult, 20 classic) were analysed for drusen parameters. Two patients with retinal angiomatous proliferation were excluded. Drusen count, area, and volume did not differ by CNV type, but the rates of change of drusen area (p = 0.046) and drusen volume (0.022) were higher in the occult group in the year preceding CNV development. Of the 49 eyes, 17 (10 occult, 7 classic) with available good quality OCT were analysed for retinal layer volumes. There was a progressive reduction in outer nuclear layer (ONL) volume (p = 0.002) and an expansion in outer plexiform layer volume (p = 0.015) in eyes that developed occult CNV.

CONCLUSION

Our study shows that rate of increase in drusen load and reduction in ONL are significant features seen in eyes developing occult CNV, highlighting new imaging markers that need to be replicated in larger studies. These markers provide insight into the pathogenesis of CNV and may serve as prognostic indicators, as classic CNV carries a poorer prognosis compared to occult CNV.

Changes in macular drusen parameters preceding the development of neovascular age-related macular degeneration

PURPOSE

To assess the rate of change in macular drusen load in fellow eyes of patients with unilateral neovascular age-related macular degeneration (AMD) to evaluate whether the change in drusen load determines the onset and type of choroidal neovascularisation (CNV).

METHODS

Subjects with unilateral neovascular AMD with a minimum of 2 years follow-up were identified retrospectively from the hospital electronic database. Drusen count, area and volume measurements at the macula of the contralateral eye were recorded using the commercial software on the Topcon 3D OCT-2000 devices over the previous 2 years. The mean rate of change of these parameters over time was compared between fellow eyes that converted to various CNV subtypes and those that did not.

RESULTS

Two hundred forty-eight patients met the inclusion criteria. Of these patients, 179 patients did not progress to neovascular AMD (Group 1) while 69 patients converted (Group 2) at the end of 2 years follow up. Mean drusen volumes and drusen areas increased significantly in Group 2 in the 2nd year by 0.031 mm³ (p < 0.001) and 0.572 mm² (p = 0.002), respectively. However, there was no difference in the rate of change between the two groups at year 1. Furthermore, for each 0.1 mm increase in the cubed root of baseline mean drusen volume increases the odds of progressing to CNV by 40% (95% CI 1.2-1.6; p < 0.001). The increase in drusen volume was higher in the occult CNV group compared to classic CNV (p = 0.048).

CONCLUSION

A significant increase in mean drusen volume occurs in eyes in the preceding 12 months prior to conversion to neovascular AMD and this change is more significant in eyes with occult CNV.

Ocular Risk Factors for Exudative AMD: A Novel Semiautomated Grading System

Purpose. To evaluate the contribution of the ocular risk factors in the conversion of the fellow eye of patients with unilateral exudative AMD, using a novel semiautomated grading system. Materials and Methods. Single-center, retrospective study including 89 consecutive patients with unilateral exudative AMD and ≥3 years of followup. Baseline color fundus photographs were graded using an innovative grading software, RetmarkerAMD (Critical Health SA). Results. The follow-up period was 60.9 ± 31.3 months. The occurrence of CNV was confirmed in 42 eyes (47.2%). The cumulative incidence of CNV was 23.6% at 2 years, 33.7% at 3 years, 39.3% at 5 years, and 47.2% at 10 years, with a mean annual incidence of 12.0% (95% CI = 0.088–0.162). The absolute number of drusen in the central 1000 and 3000 μm (P < 0.05) and the absolute number of drusen ≥125 µm in the central 3000 and 6000 µm (P < 0.05) proved to be significant risk factors for CNV. Conclusion. The use of quantitative variables in the determination of the OR of developing CNV allowed the establishment of significant risk factors for neovascularization. The long follow-up period and the innovative methodology reinforce the value of our results. This trial is registered with ClinicalTrials.gov NCT00801541.

Characteristics of fundus autofluorescence and drusen in the fellow eyes of Japanese patients with exudative age-related macular degeneration

BACKGROUND

The main purpose of this study is to investigate the characteristics of fundus autofluorescence (FAF) and area of soft drusen among the fellow eyes of unilateral typical age-related macular degeneration (typical AMD) and polypoidal choroidal vasculopathy (PCV) in Japanese patients.

METHODS

FAF images were obtained from the fellow eyes of unilateral typical AMD (n = 64), unilateral PCV (n = 95), unilateral retinal angiomatous proliferation (RAP) (n = 4) and 56 control subjects, then classified into normal, minimal-change, and abnormal patterns by two graders. Interobserver variability between two graders and intraobserver variability were assessed for FAF classifications, and cases with inconsistent decisions were finally classified by the third grader. Soft drusen were segmented and their total areas were compared between the fellow eyes of typical AMD and PCV. Area(s) with increased autofluorescence were segmented to assess the relationship with soft drusen area(s).

RESULTS

Assessment for interobserver variability between two graders and intraobserver variability in one grader showed substantial agreement (κ = 0.70) and almost perfect agreement (κ = 0.85), respectively. In the final decision mediated by third grader, the proportions of eyes with either minimal-change FAF pattern or abnormal FAF pattern in the fellow eyes of both typical AMD (37 cases, 58 %) and PCV (47 cases, 49 %) were significantly higher than that of the control cases (15 cases, 27 %; p < 0.01). The proportion of abnormal FAF pattern in the fellow eyes of typical AMD (20 cases, 31 %) was higher than that of PCV (15 cases, 16 %; p < 0.05). Total soft drusen areas in the fellow eyes of typical AMD (0.369 ± 0.718 mm(2)) were larger than those of PCV (0.173 ± 0.408 mm(2); p < 0.05), and those in the eyes with abnormal FAF pattern were larger than those with minimal-change FAF pattern or normal FAF pattern (p < 0.01). Image analysis revealed a relationship between increased autofluorescence and soft drusen, especially in the cases with large total soft drusen areas.

CONCLUSIONS

FAF characteristics were different between the fellow eyes of unilateral typical AMD and PCV in Japan, which might be due to the difference of total soft drusen areas between them.

Analyses of single nucleotide polymorphisms and haplotype linkage of LOC387715 and the HTRA1 gene in exudative age-related macular degeneration in a Chinese cohort

PURPOSE

To investigate the effect of single nucleotide polymorphisms (SNPs) and haplotypes in the genes encoding age-related maculopathy susceptibility 2 (LOC387715/ARMS2) and high-temperature requirement A-1 (HTRA1) in a case-control study in a Chinese cohort of individuals with exudative age-related macular degeneration (AMD).

METHODS

We genotyped 2 SNPs, namely, LOC387715 rs10490924 and HTRA1 rs11200638, in 159 exudative AMD patients and 140 age- and sex-matched control subjects. All the four possible haplotypes of these two SNPs were detected. Comparisons of the risk genotypes and risk or protective haplotypes across multiple populations were performed.

RESULTS

Allelic or genotype association tests yielded significant results at P < 0.001. We observed that homozygous risk genotypes (TT in rs10490924 and AA in rs11200638) were more strongly associated with AMD than the heterozygous genotypes (GT in rs10490924 and geographic atrophy in rs11200638) for both SNPs. Comparisons of the odds ratios for genotypes revealed that there is ethnic disparity in AMD prevalence, even within the Chinese population. The haplotype TA, comprising both the SNPs, was identified as an at-risk factor and was significantly associated with AMD, whereas the protective haplotype GG was significantly overrepresented in the controls (P < 0.001). The frequency of the TA haplotype was relatively higher in the Chinese population than in the white population in both groups, whereas the frequency of the GG haplotype was relatively lower in the Chinese controls than in the white and Japanese controls.

CONCLUSION

Both SNPs are significantly associated with exudative AMD in the Chinese cohort and seem to contribute equally to the disease status. A higher frequency of homozygous risk genotypes and risk haplotype and a lower frequency of protective haplotype in the Chinese may be the cause of higher prevalence of exudative AMD in the Chinese than in the whites.

Estimated prevalence and risk factor for age-related maculopathy

PURPOSE

To assess the estimate prevalence and risk factors for age-related maculopathy (ARM) in Seoul, Korea.

PATIENTS AND METHODS

We examined 9,530 subjects with, 40 years of age or older between January 2006 and December 2006 in Seoul, Korea. Subjects underwent fundus photography, clinical examinations (including blood analyses), and completed detailed questionnaires. Fundus images were graded according to definitions from the Wisconsin Age-Related Maculopathy Grading System.

RESULTS

ARM was present in 235 subjects, corresponding to an estimate prevalence of 2.46%. Hepatitis B infection (positive status for HBsAg and HBcAb), serum triglyceride levels and high density lipoprotein levels remained as significant risk factors after age-adjustment. Multivariate analyses showed that the prevalence of ARM was significantly higher in older subjects [odds ratio (OR) 1.134; 95% CI 1.114-1.154] and those who were seropositive for hepatitis B surface antigen (OR 2.566; 95% CI 1.519-4.335).

CONCLUSION

The estimated prevalence of ARM was 2.46%. Age and hepatitis B infection may increase the risk of ARM.

Development of typical age-related macular degeneration and polypoidal choroidal vasculopathy in fellow eyes of Japanese patients with exudative age-related macular degeneration

PURPOSE

To investigate the development of typical age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in fellow eyes of Japanese patients with exudative AMD.

DESIGN

Retrospective observational consecutive case series.

METHODS

Two hundred and sixteen Japanese patients were enrolled in this study from the outpatient clinic of the University of Tokyo Hospital. Ninety-one patients had typical AMD and one hundred and twenty-five patients had PCV. The average follow-up period was 33.6 and 25.1 months for typical AMD and PCV patients.

RESULTS

The cumulative incidence of involvement in fellow eyes with overall exudative AMD, including both typical AMD and PCV, was 3.4% in one year, 9.3% in three years, and 11.3% in five years. It was 3.6%, 7.3%, and 11.2% in typical AMD, and 3.2%, 11.1%, and 11.1% in PCV in one, three, and five years, respectively. Before the development of exudative AMD, patients with typical AMD had a variety of funduscopic findings including retinal pigment epithelium (RPE) atrophy, drusen, drusenoid pigment epithelial detachments (PED), and normal macula. PCV patients, on the other hand, had funduscopic findings of RPE atrophy. Inner choroidal vascular abnormality of vascular network and polypoidal formation was observed in several eyes before the clinical manifestation of exudative changes.

CONCLUSIONS

Typical AMD and PCV had similar probabilities of involving the fellow eye in unilaterally affected Japanese patients. RPE atrophy was a prevailing finding in fellow eyes of patients who developed PCV. In PCV, choroidal vascular network and polypoidal formation gradually grow before exudative changes.

Prevalence of age-related maculopathy in the adult population in China: the Beijing eye study

OBJECTIVE

To evaluate the prevalence of age-related maculopathy (ARM) in adult Chinese living in rural or urban regions of mainland China.

DESIGN

Population-based prevalence study.

METHODS

The study included 4439 subjects (aged 40 or more years) out of 5324 subjects invited to participate (response rate 83.4%). It was held in rural and urban regions of Greater Beijing. The participants underwent a detailed ophthalmic examination including fundus photography. All fundus photographs were graded by the Wisconsin Age-Related Maculopathy Grading System.

RESULTS

Fundus photographs were available for 4376 (98.6%) subjects. Early ARM was present in 122 (1.4%) of 8655 (95% confidence interval [CI] 1.16% to 1.66%) eyes or 63 (1.4%) of 4376 (95% CI 1.09% to 1.79%) subjects, late ARM in 12 (0.14%) of 8655 (95% CI 0.06% to 0.22%) eyes or seven (0.2%) of 4376 (95% CI 0.04% to 0.28%) subjects, and exudative ARM as part of late ARM in seven (0.1%) of 8655 (95% CI 0.02% to 0.14%) eyes or six (0.1%) of 4376 (95% CI 0.03% to 0.25%) subjects. The prevalence of early ARM, late ARM, and exudative ARM, respectively, increased from 0.61%, 0.07%, and 0.07% in the 40-to-44-year age group, to 1.66%, 0.26%, and 0.26% in the 55-to-59-year group, and to 2.99%, 0.90%, and 0.60% in the group aged 75 years and older. ARM was causative for visual impairment (best-corrected visual acuity in the better eye, <20/60 and > or =20/400) or blindness (visual acuity <20/400) in one subject (0.023%).

CONCLUSIONS

Visual impairment due to ARM was relatively uncommon in the adult Chinese population in rural and urban regions.