Estimating ranibizumab injection numbers and visual acuity at 12 months based on 2-month data on branch retinal vein occlusion treatment.

Anti-vascular endothelial growth factor treatment for macular edema secondary to branch retinal vein occlusion generally provides good visual acuity (VA) improvement but may require repeated injections for years. To reduce the number of patients who suffer from avoidable VA loss caused by treatment drop-out, providing prospects of the correlation between expected vision improvement and required number of injections at the early stages of treatment may be helpful. In this post hoc analysis of the phase IV, randomized, open-label ZIPANGU study, we investigated the correlation between the data from Month 2 and Month 12 in terms of VA and required ranibizumab injection numbers. Fifty-nine patients were evaluated (ranibizumab monotherapy, 29; combination therapy, 30). In the monotherapy group, patients who received 1 and 3 injections by Month 2 received a mean total of 2.8 and 8.3 injections during the year, respectively. Data from the combination group were similar. The correlation coefficients for VA scores at Months 2 and 12 were 0.60 and 0.51 for the monotherapy and combination groups, respectively (both p < 0.01). Based on VA and injection numbers at Month 2 of treatment, physicians could provide rough prospects on patients' expected final VA and required number of injections.

Correlations among age, sex, axial length, and subfoveal choroidal thickness in the choriocapillaris structure analyzed using multiple en face image averaging optical coherence tomography angiography.

PURPOSE: To analyze the structure of the choriocapillaris in healthy eyes by using averaged en face images acquired using swept source optical coherence tomography angiography and to examine the changes in the macular profile in relation to age, sex, axial length, and choroidal thickness. METHODS: This prospective, cross-sectional study included 81 eyes of 81 subjects without ophthalmologic or systemic diseases who underwent a full ophthalmologic examination, including 3 × 3-mm macular optical coherence tomography angiography. Four to nine choriocapillaris en face images were registered and averaged. The averaged images were then binarized and analyzed. RESULTS: The averaged choriocapillaris images showed a continuous capillary meshwork, whereas the unaveraged images had a granular appearance. The mean total area and size of flow voids were 0.99 ± 0.20 mm2 and 567.8 ± 201.5 µm2, respectively, and these values correlated positively with age (p = 0.002, R = 0.336 and p = 0.026, R = 0.247, respectively). Age-related gains in the mean total area and flow void size were 4.20 × 10-3 mm2 and 3.07 µm2 per year, respectively. However, the mean total area and flow void size had no significant correlation with axial length, subfoveal choroidal thickness, or sex. CONCLUSIONS: Multiple averaged en face swept source optical coherence tomography angiography is more effective than a single optical coherence tomography angiography scan for better visualizing the choriocapillaris. The total area and size of flow voids within a 3 × 3-mm macular area positively correlated with age. This technique can be useful for investigating the changes arising in macular diseases.

The randomized ZIPANGU trial of ranibizumab and adjunct laser for macular edema following branch retinal vein occlusion in treatment-naïve patients.

The ZIPANGU study assessed the efficacy and safety of ranibizumab as a one loading dose + pro re nata (one + PRN) regimen with/without focal/grid laser among treatment-naïve patients suffering from macular edema (ME) following branch retinal vein occlusion (BRVO). ZIPANGU was a phase IV, prospective, randomized, open-label, active-controlled, 12-month, two-arm, multicenter study. Treatment-naïve patients with visual impairment (19-73 letters) caused by ME, defined as central subfield thickness (CSFT) > 300 µm, due to BRVO were randomly assigned to ranibizumab monotherapy (n = 29) or combination therapy (ranibizumab + focal/grid short-pulse laser, n = 30). The primary endpoint was the number of ranibizumab injections. Secondary endpoints were mean changes in best-corrected visual acuity (BCVA) and CSFT, and safety. There were no statistically significant differences in the mean number of ranibizumab injections between monotherapy (4.3 injections) vs. combination (4.1 injections) therapy, or in CSFT. BCVA improvement in the monotherapy arm (22.0 letters) was better than the combination therapy arm (15.0 letters) (p = 0.035). Overall, both regimens appeared to be safe and well tolerated. One + PRN ranibizumab is safe and efficacious in treatment-naïve patients with ME secondary to BRVO. A conjunctive laser treatment did not lead to better functional outcomes or fewer ranibizumab injections.

Genome-wide association analyses identify two susceptibility loci for pachychoroid disease central serous chorioretinopathy.

The recently emerged pachychoroid concept has changed the understanding of age-related macular degeneration (AMD), which is a major cause of blindness; recent studies attributed AMD in part to pachychoroid disease central serous chorioretinopathy (CSC), suggesting the importance of elucidating the CSC pathogenesis. Our large genome-wide association study followed by validation studies in three independent Japanese and European cohorts, consisting of 1546 CSC samples and 13,029 controls, identified two novel CSC susceptibility loci: TNFRSF10A-LOC389641 and near GATA5 (rs13278062, odds ratio = 1.35, P = 1.26 × 10-13; rs6061548, odds ratio = 1.63, P = 5.36 × 10-15). A T allele at TNFRSF10A-LOC389641 rs13278062, a risk allele for CSC, is known to be a risk allele for AMD. This study not only identified new susceptibility genes for CSC, but also improves the understanding of the pathogenesis of AMD.

Retinal oximetry in branch retinal vein occlusion.

PURPOSE: To measure retinal oxygen saturation (SO2 ) in eyes with branch retinal vein occlusion (BRVO). METHODS: Retinal oximetry was performed using the Oxymap T1 retinal oximeter in 50 eyes (50 patients) with resolved BRVO. SO2 was calculated in each major retinal artery and vein in four quadrants. The superior or inferior hemisphere with BRVO was categorized as the affected hemisphere and the other as the unaffected hemisphere. RESULTS: Oxymap T1 allowed us to measure SO2 in major retinal vessels. Both arterial and venous SO2 in the affected hemisphere were significantly higher than those in the unaffected hemisphere. However, there was no significant difference in arteriovenous (A-V) difference in SO2 between the affected and unaffected hemispheres. Of the 50 included eyes, 32 had non-ischemic BRVO and 18 had ischemic BRVO. In the affected hemisphere, arterial SO2 was significantly higher in ischemic BRVO (106.9 ± 8.8%) than in non-ischemic BRVO (101.3 ± 9.2%, p = 0.044). There were no significant differences in venous SO2 between non-ischemic and ischemic BRVO. Consequently, the A-V difference in SO2 was significantly higher in ischemic BRVO (51.9 ± 13.9%) than in non-ischemic BRVO (43.4 ± 11.5%, p = 0.028). In multiple regression analysis, the type of perfusion (non-ischemic or ischemic) had associations with arterial SO2 (ß = 0.365, p = 0.013) and with A-V differences in SO2 in the affected hemisphere (ß = 0.406, p = 0.006). CONCLUSION: In ischemic BRVO, arterial SO2 and the A-V difference in SO2 in the affected hemisphere were significantly higher than in non-ischemic BRVO.

MACULAR ATROPHY FINDINGS BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY COMPARED WITH FUNDUS AUTOFLUORESCENCE IN TREATED EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To compare the areas of choriocapillaris (CC) nonperfusion and macular atrophy (MA) in treated exudative age-related macular degeneration. METHODS: This was a prospective, observational, cross-sectional study. Forty-four eyes exhibiting MA (42 patients with age-related macular degeneration), with a dry macula, underwent fundus autofluorescence and optical coherence tomography angiography. The area of MA detected by fundus autofluorescence and CC nonperfusion detected by optical coherence tomography angiography was measured using image analysis software. The rates of concordance between the MA and CC nonperfusion areas were calculated. We qualitatively and quantitatively compared the areas of MA and CC nonperfusion in age-related macular degeneration eyes. RESULTS: The mean areas of MA and CC nonperfusion were 5.95 ± 4.50 mm and 10.66 ± 7.05 mm, respectively (paired t-test, P < 0.001). In 39 eyes (88.6%), the CC nonperfusion area was larger than the MA area, and the mean CC nonperfusion area was significantly larger than the mean MA area. Fundus autofluorescence matching optical coherence tomography angiography showed that the CC nonperfusion area was almost included in the MA area. The mean concordance rate for the MA area inside the CC nonperfusion area was 87.7 ± 13.9%. CONCLUSION: The MA and CC nonperfusion areas markedly overlapped. The area of CC nonperfusion correlated with the MA area. Choroidal ischemia might be involved in the pathogenesis of MA in treated age-related macular degeneration.

Persistent metamorphopsia associated with branch retinal vein occlusion.

PURPOSE: To investigate longitudinal changes in metamorphopsia associated with branch retinal vein occlusion. METHODS: In this prospective observational case series, we included 32 eyes (32 patients) with branch retinal vein occlusion and acute macular edema. Eyes were treated as needed with intravitreal ranibizumab injections for 12 months. At baseline and 1, 6, and 12 months after initiating treatment, metamorphopsia was quantified using M-CHARTS. Retinal morphology was examined through optical coherence tomography. RESULTS: Logarithm of the minimum angle of resolution visual acuity progressively improved from 0.342 ± 0.304 (Snellen equivalent: 20/44) at baseline to 0.199 ± 0.259 (20/32) and 0.118 ± 0.195 (20/26) at 1 and 12 months, respectively (both P < 0.001). The M-CHARTS score significantly decreased from 0.63 ± 0.61 at baseline to 0.45 ± 0.50 at 1 month (P = 0.044), but no further improvement was achieved with 1 year of additional treatment (6 months: 0.47 ± 0.53 [P = 0.094] and 12 months: 0.50 ± 0.44 [P = 0.173]). Three (13.6%) of 22 eyes with baseline metamorphopsia had complete metamorphopsia resolution. At 12 months, the M-CHARTS score was correlated with baseline foveal thickness (r = 0.373, P = 0.035) and the baseline M-CHARTS score (r = 0.503, P = 0.003). A multiple regression analysis revealed that only the baseline M-CHARTS score was correlated with the 12-month M-CHARTS score (ß = 0.460, P = 0.027). CONCLUSIONS: Eyes with branch retinal vein occlusion often have persistent metamorphopsia, even when visual acuity and retinal morphology improve. Metamorphopsia at 12 months was correlated with metamorphopsia and foveal thickness at baseline.

One-year outcomes of fixed treatment of intravitreal aflibercept for exudative age-related macular degeneration and the factor of visual prognosis.

The aim of this study was to investigate the efficacy of periodic intravitreal aflibercept (IVA) in exudative age-related macular degeneration, and to explore the predictive factors for visual outcome.This is a prospective interventional case series.Fifty-two eyes of 52 treatment-naïve age-related-macula-degeneration patients were enrolled. All participants received IVA bimonthly following 3 monthly loading dose. The primary endpoint was change in best corrected visual acuity (BCVA) and central retinal thickness (CRT), and the secondary outcomes included changes in subfoveal choroidal thickness (SCT), macular atrophy (MA), and retinal average sensitivity (AS) determined by microperimetry at 12 months compared with baseline. The predictive factors for the change of BCVA were examined.Of 52 enrolled patients, 4 patients were drop out. Remaining 48 patients were examined. Mean logMAR BCVA significantly improved from 0.42 ±â€Š0.37 at baseline to 0.29 ±â€Š0.34 at 12 months (P = .008). Mean CRT and SCT significant reduced from 285.6 ±â€Š135.2 µm, 247.9 ±â€Š96.7 µm at baseline to 233.4 ±â€Š98.0 µm, 208.1 ±â€Š94.6 µm at 12 months, respectively (P < .001). At 12 months, 35 eyes of 48 eyes (72.3%) were archived dry macula. MA occurred in 7 eyes of 35 eyes with dry macula at 12 months (20.0%). AS was significant improved (P = .027) between baseline (median: 15.7 dB) and 12 months (median: 19.5 dB). The BCVA of the cases with MA involved fovea was significant worse. Age was significantly predicted for the BCVA at 12 months.IVA administered over 1 year improved BCVA, AS, and morphological findings, and the predictive factors for BCVA were age and MA-involved fovea.

Clinical Features of Central Serous Chorioretinopathy With Type 1 Choroidal Neovascularization.

PURPOSE: To evaluate the type 1 choroidal neovascularization (CNV) incidence and associated factors in eyes with central serous chorioretinopathy (CSC). DESIGN: Retrospective case series. METHODS: Records of 363 eyes (324 patients) with CSC were reviewed. Age, sex, CSC type, choroidal vascular hyperpermeability (CVH), best-corrected visual acuity (BCVA), subfoveal choroidal thickness (SCT), and systemic hypertension (HT) were assessed and compared between subjects with and without neovascular CSC. RESULTS: We identified 219 and 144 eyes with chronic and acute CSC, respectively. The mean participant age was 55.2 ± 12.0 years, and 58 (15.6%) eyes had neovascular CSC. Age (no CNV: 54.8 ± 12.1 years, CNV: 57.3 ± 10.9 years; P = .118) and SCT (no CNV: 388.0 ± 104.5 µm, CNV: 377.4 ± 108.9 µm; P = .487) were comparable between eyes with and without CNV. However, BCVA (logarithm of the minimum angle of resolution) was significantly worse in subjects with CNV (0.28 ± 0.33 [20/38] vs 0.15 ± 0.29 [20/28]; P = .014). Neovascular CSC occurred more often in women (72 [23.6%] vs 20 [34.5%], P = .099) and in cases of chronic CSC (171 [56.1%] vs 48 [82.8%], P < .001), CVH (205 [67.2%] vs 58 [100%], P < .001), and HT (91 [29.8%] vs 24 [41.4%], P = .092). Chronic CSC (P = .001), female sex (P = .075), and poor BCVA (P = .091) were associated with neovascular CSC (multiple regression). CONCLUSIONS: Chronic CSC, female sex, CVH, and poor BCVA are risk factors for CNV in eyes with CSC.

CFH and VIPR2 as susceptibility loci in choroidal thickness and pachychoroid disease central serous chorioretinopathy.

Central serous chorioretinopathy (CSC) is a common disease affecting younger people and may lead to vision loss. CSC shares phenotypic overlap with age-related macular degeneration (AMD). As recent studies have revealed a characteristic increase of choroidal thickness in CSC, we conducted a genome-wide association study on choroidal thickness in 3,418 individuals followed by TaqMan assays in 2,692 subjects, and we identified two susceptibility loci: CFH rs800292, an established AMD susceptibility polymorphism, and VIPR2 rs3793217 (P = 2.05 × 10-10 and 6.75 × 10-8, respectively). Case-control studies using patients with CSC confirmed associations between both polymorphisms and CSC (P = 5.27 × 10-5 and 5.14 × 10-5, respectively). The CFH rs800292 G allele is reportedly a risk allele for AMD, whereas the A allele conferred risk for thicker choroid and CSC development. This study not only shows that susceptibility genes for CSC could be discovered using choroidal thickness as a defining variable but also, deepens the understanding of differences between CSC and AMD pathophysiology.

CLINICAL FEATURES OF TREATED AND UNTREATED TYPE 1 IDIOPATHIC MACULAR TELANGIECTASIA WITHOUT THE OCCURRENCE OF SECONDARY CHOROIDAL NEOVASCULARIZATION FOLLOWED FOR 2 YEARS IN JAPANESE PATIENTS.

PURPOSE: To evaluate the clinical features of Type 1 idiopathic macular telangiectasia (IMT) followed up for 2 years. METHODS: Forty-nine patients with unilateral Type 1 IMT were examined. Thirty-one IMT eyes were treated with direct laser photocoagulation and/or intravitreal bevacizumab; the remaining 18 eyes, with good vision or slight macular edema, were untreated. Changes in best-corrected visual acuity and central retinal thickness between baseline and 24 months after the initial visit were examined. RESULTS: Of 49 eyes, nine were treated with direct laser photocoagulation, 12 with laser photocoagulation and intravitreal bevacizumab, 10 with intravitreal bevacizumab monotherapy, whereas 18 did not receive any treatment. The mean logarithm of the minimum angle of resolution best-corrected visual acuity was 0.20 ± 0.19 (median, 20/29) and 0.13 ± 0.22 (median, 20/25) at baseline and 24 months, respectively (P = 0.023). The mean central retinal thickness was 375.0 ± 94.5 µm and 315.3 ± 78.5 µm at baseline and 24 months, respectively (P < 0.001). Retinal vein occlusion and retinal macroaneurysm occurred in six eyes and one eye, respectively, during follow-up. CONCLUSION: Treatment with laser photocoagulation and/or intravitreal bevacizumab may be effective for Type 1 IMT, 36.7% of IMT eyes required no treatment over a 2-year follow-up, and other retinal vascular events were not uncommon.

Metamorphopsia associated with central retinal vein occlusion.

This prospective study aimed to investigate metamorphopsia in eyes with central retinal vein occlusion (CRVO) and included 28 eyes (28 patients) with unilateral CRVO that had macular edema (ME) in the acute phase. The ME was treated with anti-vascular endothelial growth factor agents. At baseline and at 1 and 6 months after initiation of treatment, quantitative measurements of metamorphopsia were performed using M-CHARTS and the retinal morphologic changes were examined by optical coherence tomography. At baseline, metamorphopsia was detected on M-CHARTS in 14 (50.0%) eyes. The mean M-CHARTS score was 0.37 ± 0.53. At 1 month and 6 months after initiation of treatment, there was substantial resolution of ME and significant recovery of visual acuity. In contrast, metamorphopsia was still detected in 16 eyes at 6 months; the mean M-CHARTS scores were 0.29 ± 0.37 at 1 month and 0.32 ± 0.38 at 6 months, and had not significantly improved from baseline (p = 0.580, and p = 0.604, respectively). Although the M-CHARTS score at 6 months was associated with the baseline M-CHARTS score (p = 0.004), it did not have any associations with morphologic parameters at baseline. However, the M-CHARTS score at 6 months was significantly associated with foveal photoreceptor status, height of serous detachment, and parafoveal thickening at 1 month. Metamorphopsia associated with CRVO could be quantified using M-CHARTS, and often persisted in contrast with the recovery of visual acuity and resolution of ME after treatment with anti-vascular endothelial growth factor agents.

Paravascular inner retinal abnormalities in healthy eyes.

PURPOSE: To investigate the prevalence and characteristics of paravascular inner retinal abnormalities in healthy eyes. MATERIALS AND METHODS: In this prospective observational case series, we included 178 healthy eyes (178 patients) with no ocular diseases. Eyes with co-existing ocular diseases, e.g., epiretinal membrane, glaucoma, or high myopia, were excluded from the current study. The posterior pole and paravascular areas of the temporal arcade vessels were comprehensively examined by dense radial scanning of optical coherence tomography (OCT) with the extended field imaging technique. RESULTS: On fundus photography, no inner retinal abnormalities were detected along the temporal arcade vessels. On OCT sections, paravascular inner retinal abnormalities were seen in 77 (43.3%) eyes. In 71 (39.9%) eyes, inner retinal cystoid or fissure-like spaces that had no connection to the vitreous cavity were seen adjacent to the temporal arcade vessels. Most of these lesions were detected only on several consecutive OCT sections. In four (2.2%) eyes, inner retinal cleavages with openings to the vitreous cavity were seen adjacent to the temporal arcade vessels. These lesions were more frequently detected in the inferior hemisphere and along the major retinal veins. No eyes showed typical broad defects of the inner retinal tissue. There were no significant differences in age, gender, visual acuity, refractive error, or axial length between eyes with or without paravascular inner retinal abnormalities. CONCLUSIONS: Paravascular cystoid or fissure-like spaces were frequently seen in the inner retina of healthy eyes. However, we detected no typical paravascular inner retinal defects in healthy eyes.

The effect of vitreomacular and cataract surgery on oxygen saturation in retinal vessels.

PURPOSE: To evaluate the effects of vitreomacular and cataract surgery on retinal oximetry in vitreomacular disease. PATIENTS AND METHODS: Thirty-eight eyes with epiretinal membrane (ERM) and 15 with idiopathic macular hole (MH) underwent 25 gauge pars plana vitrectomy combined with cataract surgery and intraocular lens implantation. Retinal oximetry was performed using the Oxymap T1 before, 1 month, and 6 months after surgery. Oxymap T1 simultaneously captures monochrome images of the fundus at two different wavelengths of light. Built-in Oxymap Analyzer software measures the oxygen saturation and vessel diameter. RESULTS: Mean arterial oxygen saturation significantly increased from 96.8%±6.2% to 100.2%±5.8% at 1 month and to 99.6%±5.8% at 6 months after surgery (P<0.01). Mean venous oxygen saturation also significantly increased from 54.6%±7.5% to 61.2%±6.4% at 1 month and to 62.6%±5.9% at 6 months after surgery (P<0.01). Mean arteriovenous (A-V) difference decreased from 42.2%±6.6% to 39.0%±7.8% at 1 month and to 37.0%±6.9% at 6 months after surgery (P<0.01). The ERM and MH groups showed similar changes in retinal oxygen saturation. However, there were no significant changes in the caliber of major retinal vessels after surgery (from 125.2±15.2 µm to 124.0±15.4 µm in artery, from 168.7±14.6 µm to 169.8±14.6 µm in vein). CONCLUSION: Oxymap T1 was able to measure the increase in oxygen saturation in retinal arteries and veins, which led to a decrease in the A-V difference in oxygen saturation after vitrectomy combined with cataract surgery.

Effect of topical isopropyl unoprostone on macular atrophy progression in eyes with exudative age-related macular degeneration.

BACKGROUND: To evaluate the efficacy and safety of topical isopropyl unoprostone (IU) in treating macular atrophy in age-related macular degeneration (AMD) patients. METHODS: Fifty-two AMD patients with macular atrophy were included and randomly assigned (1:1) to the treatment (topical 0.15% IU) or placebo group. Subjects used study eye drops 3 times a day for 54 weeks. The macular atrophy was documented on fundus autofluorescence photographs and measured using RegionFinder. The enlargement rate of macular atrophy and the changes in visual acuity were examined statistically between baseline and 54 weeks. RESULTS: Forty-eight subjects were included in the analyses because 4 subjects withdrew from the study. The differences between the IU and placebo groups in mean and median area of macular atrophy were not statistically significant at baseline. The baseline median lesion size of macular atrophy was 2.33 mm in the IU group and 1.63 mm in the placebo group (P = 0.51). The intergroup difference in the enlargement ratio of macular atrophy (21 ±â€Š15% in the IU group and 111 ±â€Š96% in the placebo group) was statistically significant (P < 0.001). Additionally, visual acuity tended to improve over baseline in the IU group. No serious adverse events were observed. CONCLUSIONS: Topical IU therapy is safe and effective for treating macular atrophy in AMD patients.

ASSOCIATION BETWEEN PARAFOVEAL CAPILLARY NONPERFUSION AND MACULAR FUNCTION IN EYES WITH BRANCH RETINAL VEIN OCCLUSION.

PURPOSE: To investigate the parafoveal perfusion status of the superficial and deep capillary layer in eyes with resolved branch retinal vein occlusion, and to study its effects on retinal sensitivity. METHODS: In 27 enrolled eyes (27 patients) with resolved branch retinal vein occlusion, superficial and deep capillaries in the macular area (3- × 3-mm, centered on the fovea) were examined with optical coherence tomography angiography. Retinal sensitivity was examined with fundus-monitored microperimetry. RESULTS: Optical coherence tomography angiography clearly showed the parafoveal superficial and deep capillaries individually. On the affected side of retina, 25 eyes (92.6%) showed capillary nonperfusion; 23 (85.2%) in the superficial layer and 22 (81.5%) in the deep layer. Capillary nonperfusions of both layers frequently overlapped and appeared to be connected with each other. Mean (±SD) retinal sensitivity at the superficial capillary nonperfusion was 19.2 ± 6.3 dB, significantly lower than that at the superficial capillary perfusion (24.4 ± 2.8 dB, P < 0.001). Similarly, mean retinal sensitivity at the deep capillary nonperfusion was 20.8 ± 5.0 dB, significantly lower than that at deep capillary perfusion (24.3 ± 2.8 dB, P = 0.0016). Mean retinal sensitivity with superficial capillary nonperfusion was significantly lower than that with deep capillary nonperfusion (P = 0.0226). CONCLUSION: Optical coherence tomography angiography visualized parafoveal capillary nonperfusion in superficial and deep layers individually in eyes with resolved branch retinal vein occlusion. Retinal sensitivity was significantly reduced at these capillary nonperfusions.

Retinal Oximetry in a Healthy Japanese Population.

PURPOSE: To establish the normative database of retinal oximetry using Oxymap T1 in a healthy Japanese population, and study the reproducibility of the measurements in Japanese. METHODS: We measured oxygen saturation in the major retinal vessels with Oxymap T1 in 252 eyes of 252 healthy Japanese subjects. Fundus images acquired using Oxymap T1 were processed using built-in Oxymap Analyzer software. Reproducibility of retinal oximetry was investigated using 20 eyes of 20 healthy subjects. RESULTS: The mean retinal oxygen saturation of 4 quadrants in healthy Japanese was 97.0 ± 6.9% in arteries and 52.8 ± 8.3% in veins. The mean arteriovenous difference in oxygen saturation was 44.2 ± 9.2%. Both arterial and venous oxygen saturation were significantly lower in the temporal side of the retina, especially in the temporal-inferior vessels. However, the arteriovenous difference in oxygen saturation was limited in the 4 quadrants. Interphotograph, intervisit, and interevaluator intraclass correlation coefficients were 0.936-0.979, 0.809-0.837, and 0.732-0.947, respectively. In the major retinal arteries, oxygen saturation increased with age (r = 0.18, p<0.01), at a rate of 0.67% per 10 years. However, venous oxygen saturation showed no correlation with age. CONCLUSIONS: This study provides the normative database for the Japanese population. The arterial saturation value appears to be higher than other previous studies. Mean retinal oximetry in 4 quadrants with Oxymap T1 has high reproducibility.