Fingerprint sign of the Henle fibre layer in epiretinal membrane: a cross-sectional and longitudinal study.

PURPOSE: To investigate the incidence and distribution of fingerprint-like microwaves in the Henle fibre layer (HFL) of the eyes with epiretinal membrane (ERM). METHODS: Patients with idiopathic ERM were included. The fingerprint sign was defined using en-face optical coherence tomography images of the HFL, and its extent was classified into three grades. RESULTS: At baseline, fingerprint sign was found in 70 of 83 (84.3%) eyes with ERM and was more frequently observed in eyes with a higher ERM stage (P < 0.001). Its extent increased (P < 0.001) with an increase in ERM stage or the central macular thickness (P < 0.001). Best corrected visual acuity (BCVA) was worse in eyes with a fingerprint sign than in those without (P = 0.024). Metamorphopsia was more common in eyes with a greater extent of fingerprint-like microwaves (P = 0.048). The fingerprint sign persisted over a mean follow-up period of 18.0 ± 23.3 without surgery. In 45 eyes that underwent surgery, the extent of fingerprint-like microwaves decreased at 1.2 months (P = 0.001), and further decreased at 13.7 months postoperatively (P = 0.019). However, the proportion of eyes with a fingerprint sign after surgery was similar to that observed preoperatively (P = 0.912). CONCLUSIONS: Fingerprint-like microwaves were commonly found in eyes with ERM and were associated with ERM severity and BCVA. The microwaves remained long after surgery, although their extent may have decreased after the ERM was resolved. These results suggest that ERM traction may cause long-lasting changes in the HFL.

Hyperreflective foci in the choroid of normal eyes.

PURPOSE: To investigate hyperreflective choroidal foci (HCF) using en face swept-source optical coherence tomography (SS-OCT) and determine the factors that contribute to the distribution of HCF in normal eyes. METHODS: In this retrospective study, we included healthy eyes with a normal fundus. HCF were defined as hyperreflective spots on en face SS-OCT images. The number, mean area, total area, and circularity of the HCF were compared with various choroid measurements obtained using SS-OCT, SS-OCT angiography, and fundus photography. RESULTS: We investigated 51 eyes from 51 patients. The mean patient age was 56.0 ± 14.7 years, and 32 (62.7%) were female. The number and total area of HCF did not differ between the female and male patients and the right and left eyes. The number of HCF was correlated with the stromal area of the choroid (r = 0.291, P = 0.040) and subfoveal choroidal vascularity index (r = - 0.364, P = 0.009). The total area of HCF was correlated with the stromal area of the choroid (r = 0.283, P = 0.045). However, the number and total area of HCF were not correlated with age, degree of macular tessellation, subfoveal choroidal thickness, and choriocapillaris vascular density and flow void area. CONCLUSION: HCF were observed in normal eyes, and their distribution was associated with the underlying stromal component of the choroid. The results of this study can be used as a reference for determining abnormal hyperreflective foci in the choroid of the eyes with various diseases.

MORPHOLOGIC AND ANATOMICAL FEATURES OF TYPE 1 MACULAR NEOVASCULARIZATION TRUNKS IN AGE-RELATED MACULAR DEGENERATION USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PURPOSE: To evaluate the morphologic features of macular neovascularization (MNV) trunks at different layers using optical coherence tomography angiography. METHODS: Type 1 MNV trunks in age-related macular degeneration were retrospectively evaluated at the subretinal pigment epithelium and sub-Bruch membrane (subBM) layers. The detectability and location of the trunks were compared. MNV trunks at the subBM layer on optical coherence tomography angiography B-scans were evaluated using a flow overlay. The correlations of the MNV trunk with optical coherence tomography angiography and optical coherence tomography parameters were evaluated. RESULTS: Among the 63 included eyes, 27 showed core vessels at the subretinal pigment epithelium layer and 52 showed MNV trunks at the subBM layer, which were connected with the MNV at the subretinal pigment epithelium layer. The locations of the MNV trunks in each layer were different. MNV trunk types at the subBM layer were related to disease duration, distance from the large choroidal vessels, and MNV vessel density. The large choroidal vessel diameter was correlated with the MNV trunk diameter at the subBM layer. CONCLUSION: Macular neovascularization trunks at the subBM layer were detected more frequently than distal MNV trunks at the subretinal pigment epithelium layer. Macular neovascularization trunk features at the subBM layer may be related to disease duration and a large choroidal vessel.

CLINICAL IMPLICATION OF RETINAL NERVE FIBER LAYER SCHISIS AND MACULAR FLUORESCEIN LEAKAGE IN PRIMARY IDIOPATHIC EPIRETINAL MEMBRANE.

PURPOSE: We evaluated the relationship between macular fluorescein leakage and retinal nerve fiber layer (RNFL) schisis and investigated the visual prognostic values after pars plana vitrectomy (PPV) and idiopathic epiretinal membrane removal. METHODS: We analyzed the correlations between preoperative optical coherence tomography (OCT) parameters and macular leakage. The final best-corrected visual acuity and central macular thickness were compared according to the presence or absence of macular leakage and RNFL schisis. RESULTS: In 80 eyes with idiopathic epiretinal membrane treated with PPV and membrane peeling, preoperative macular leakage was associated with the presence of preoperative RNFL schisis and inner nuclear layer microcysts. Eyes with both macular leakage and RNFL schisis showed worse postoperative best-corrected visual acuity than those without both factors. CONCLUSION: In the presence of macular fluorescein leakage and RNFL schisis, postoperative best-corrected visual acuity is worse, and improvements in the central macular thickness are greater than those in the absence of both factors.

Choroidal thickness profile and clinical outcomes in eyes with polypoidal choroidal vasculopathy.

PURPOSE: To investigate the relationship between choroidal thickness (CT) profile and clinical outcomes after anti-vascular endothelial growth factor (VEGF) treatment in polypoidal choroidal vasculopathy (PCV). METHODS: Medical records of patients diagnosed with PCV who received anti-VEGF treatment over 12 months were reviewed. Subfoveal CT (SFCT) and peripapillary CT (PCT) were measured on swept-source optical coherence tomography images. Patients were divided into various groups based on choroidal profiles including SFCT, nasal PCT (nPCT) and ratio of SFCT to nPCT (SFCT/nPCT). Clinical outcomes were compared between the thin and thick CT groups. RESULTS: A total of 65 patients with PCV patients were included. After ant-VEGF treatment, SFCT was significantly decreased after anti-VEGF treatment (P = 0.001), but nasal PCT (nPCT) was not. Clinical outcomes were not different between the thin and thick SFCT groups. Total number of injections during the 12 months was significantly fewer in the thin nPCT group (3.4 ± 1.3) than in the thick nPCT group (4.5 ± 1.8) (P = 0.020). Complete resolution after loading injections was more frequently observed in the high SFCT/nPCT ratio (> 1.9) group (87.9%) than in the low SFCT/nPCT ratio (≤ 1.90) group (59.4%) (P = 0.009). The ratio of SFCT/nPCT showed the best predictive ability for poor responders (area under curve = 0.771). CONCLUSION: These results suggest that baseline nPCT and SFCT/nPCT ratio could be a good biomarker that reflects clinical outcomes after anti-VEGF treatment in PCV.

GANGLION CELL-INNER PLEXIFORM LAYER THICKNESS IN EYES WITH NONEXUDATIVE AGE-RELATED MACULAR DEGENERATION OF DIFFERENT DRUSEN SUBTYPES.

PURPOSE: We sought to investigate the ganglion cell-inner plexiform layer (GCIPL) thickness in eyes with nonexudative age-related macular degeneration. METHODS: We classified eyes into four categories-pachydrusen, soft drusen, subretinal drusenoid deposit (SDD), and soft drusen with SDD-and compared the baseline mean macular GCIPL thickness according to the Early Treatment Diabetic Retinopathy Study grid and its change between groups. RESULTS: We classified 53, 29, 36, and 34 eyes into the four categories, respectively. The mean GCIPL thickness values in the 3-mm area were 82.61 ± 9.54 µm for the pachydrusen group, 79.11 ± 10.26 µm for the soft drusen group, 77.72 ± 6.04 µm for the SDD group, and 71.63 ± 8.69 µm for the soft drusen with SDD group (P < 0.001). The soft drusen with the SDD group showed a greater change in GCIPL thickness (-2.50 ± 0.29 µm/year) in the 3-mm area as compared with the pachydrusen group (-0.18 ± 0.35 µm/year), soft drusen group (-0.55 ± 0.36 µm/year), and SDD group (-0.55 ± 0.37) (all P < 0.001). CONCLUSION: The GCIPL thickness varied according to the type of nonexudative age-related macular degeneration. The thinner baseline GCIPL and its greater change in eyes with soft drusen with SDD may suggest that these eyes are experiencing more prominent neuroretinal degeneration in the central 3-mm area than those in the other groups.

FEATURES OF THE MACULAR AND PERIPAPILLARY CHOROID AND CHORIOCAPILLARIS IN EYES WITH NONEXUDATIVE AGE-RELATED MACULAR DEGENERATION.

PURPOSE: We investigated macular and peripapillary choroidal thickness (CT) and flow voids in the choriocapillaris in eyes with nonexudative age-related macular degeneration. METHODS: We retrospectively reviewed the medical records of patients with nonexudative age-related macular degeneration and classified their eyes into three categories: pachydrusen, drusen, and subretinal drusenoid deposit. Mean macular and peripapillary CT and choriocapillaris flow void area were compared among the three groups. RESULTS: The three groups included 29, 33, and 33 patients, respectively. The mean macular and peripapillary CT findings were 260.64 ± 75.85 µm and 134.47 ± 46.28 µm for the pachydrusen group; 163.63 ± 64.08 µm and 93.47 ± 39.07 µm for the drusen group; and 95.33 ± 28.87 µm and 56.06 ± 11.64 µm for the subretinal drusenoid deposit group (all, P < 0.001). Mean macular and peripapillary flow void area varied among the subretinal drusenoid deposit group (57.07 ± 6.16% and 55.38 ± 6.65%), drusen group (58.30 ± 6.98% and 49.11 ± 9.11%) and pachydrusen group (50.09 ± 5.77% and 45.47 ± 8.06%) (all P < 0.001). CONCLUSION: The peripapillary CT and flow voids in the choriocapillaris varied according to the features of drusen in nonexudative age-related macular degeneration eyes. Greater flow voids and thinner CT in eyes with subretinal drusenoid deposits may suggest that these eyes have diffuse choroidal abnormalities both in and outside the macula.

MORPHOLOGIC FEATURES OF THE RETINAL PIGMENT EPITHELIUM AND ASSOCIATED CHORIORETINAL CHARACTERISTICS IN EYES WITH EARLY AGE-RELATED MACULAR DEGENERATION AND SUBRETINAL DRUSENOID DEPOSITS.

PURPOSE: To investigate the features of the retinal pigment epithelium (RPE) on optical coherence tomography in eyes with early age-related macular degeneration with subretinal drusenoid deposit. METHODS: We classified the eyes into three types: nonundulating RPE, undulating RPE, and wedge-shaped RPE. We compared the retinal vessel densities, retinal thickness, and choroidal thickness of a 3-mm-diameter zone. RESULTS: We classified 33, 27, and 20 as nonundulating RPE, undulating RPE, and wedge-shaped RPE eyes, respectively. The vascular densities of the superficial and deep capillary plexus showed differences; nonundulating RPE group (23.93 ± 2.26% and 23.54 ± 1.78%), undulating RPE group (22.29 ± 2.80% and 21.94 ± 2.42%), and wedge-shaped RPE group (21.93 ± 2.70% and 20.63 ± 2.42%, P = 0.010 and P < 0.001). The mean retinal thickness and choroidal thickness were also different, nonundulating RPE group (298.26 ± 13.81 µm and 180.08 ± 55.49 µm), undulating RPE group (285.29 ± 21.88 µm and 148.45 ± 55.08 µm), and wedge-shaped RPE group (274.86 ± 20.62 µm and 135.75 ± 39.77 µm) (P = 0.001 and P = 0.007). CONCLUSION: Altered features of the RPE on optical coherence tomography may indicate advancement in disease and be part of an overall degeneration process in these eyes.

Features of the choriocapillaris on four different optical coherence tomography angiography devices.

PURPOSE: To investigate the features of the choriocapillaris using four different optical coherence tomography angiography (OCTA) devices. METHODS: OCTA images of the choriocapillaris from consecutive healthy subjects were obtained with four different OCTA devices (Zeiss PLEX Elite, Topcon DRI OCT-1 Atlantis, Zeiss AngioPlex, and Heidelberg Spectralis OCTA). The 3 × 3 mm OCTA images were processed with ImageJ. The mean vascular density and mean flow void area of the choriocapillaris were compared among devices. Flow voids were analyzed with two different imaging adjustment methods, auto-local threshold with the Phansalkar method and a method using a device-specific threshold value. RESULTS: The mean vascular density of the choriocapillaris differed among the four devices (all P < 0.001). The mean flow void area as measured with the auto-local threshold method also differed among devices (P < 0.001) and was not correlated among devices (all P > 0.05). Results for mean flow void area measured with a device-specific threshold value using the Plex-Elite and DRI OCT-1 Atlantis were correlated (ß = 2.271, P < 0.001), but there were no correlations among other devices (P > 0.05). For the Plex-Elite and DRI OCT-1 Atlantis, the mean flow void area was positively correlated between the two image adjustment methods (all P < 0.05). CONCLUSIONS: Vascular densities and flow void areas of the choriocapillaris varied according to the device used and the image adjustment method. The characteristics of different devices and the image adjustment method should be considered for analysis of the choriocapillaris.

Short-term effects of anti-vascular endothelial growth factor on peripapillary choroid and choriocapillaris in eyes with neovascular age-related macular degeneration.

PURPOSE: To investigate the effects of anti-vascular endothelial growth factor (anti-VEGF) on the peripapillary choroid and choriocapillaris in eyes with neovascular age-related macular degeneration (nAMD). METHODS: We included consecutive patients who underwent three monthly intravitreal injections of aflibercept or ranibizumab for nAMD, followed by swept-source optical-coherence tomography angiography (SS-OCTA). Peripapillary choroidal thickness (CT) and vascular density (VD) of the peripapillary choriocapillaris were measured in SS-OCT and OCTA images at baseline and at 1 month after three monthly injections of anti-VEGF. RESULTS: In 68 eyes of 68 patients with nAMD, peripapillary CT decreased from 124.5 ± 69.9 µm to 116.5 ± 68.2 µm (P = 0.003) after three monthly intravitreal injections of anti-VEGF. The mean vascular density (VD) of the peripapillary choriocapillaris also decreased from 73.99 ± 6.33 to 71.82 ± 6.51 (P < 0.001). The change in the peripapillary choriocapillaris VD was significantly affected by baseline peripapillary choriocapillaris VD, baseline peripapillary CT, and type of nAMD (P = 0.004, P = 0.028, P = 0.015, respectively). The baseline VD of the choriocapillaris was lower in non-responders (median, 70.63; 25-75%, 68.12-71.27) than in responders (median, 75.32; 25-75%, 70.09-79.96) (P = 0.032). CONCLUSION: These results suggest that anti-VEGF injection influences the peripapillary choriocapillaris flow out of exudative lesions, and that its effects depend on the baseline status of the choroid and choriocapillaris.

Choriocapillaris flow features and choroidal vasculature in the fellow eyes of patients with acute central serous chorioretinopathy.

PURPOSE: The purpose of the study is to investigate the characteristics of choriocapillaris flow based on the underlying choroidal vasculature in fellow eyes with central serous chorioretinopathy (CSC). METHODS: We included 57 patients with CSC and normal controls. Characteristics of choriocapillaris flow were evaluated using swept-source optical coherence tomography (OCT) angiography. We divided the choroidal layer into the vascular and stromal beds according to the choroid vessels on en-face OCT images. We compared the flow void area and mean vascular density of the choriocapillaris according to the underlying choroidal beds in the CSC and control group. RESULTS: The mean vascular density of the choriocapillaris in the CSC group was not different from that of the control group (P = 0.289). The flow void area was more frequently found in the CSC group (59.6%) than in the control group (29.8%, P = 0.002). The presence of the flow void area in the CSC group was associated with greater macular choroidal thickness (P = 0.004). In the CSC group, the mean flow void area and ratio of the choriocapillaris over the vascular bed were larger than those over the stromal bed (all P < 0.001). CONCLUSIONS: The location of the flow void area of the choriocapillaris was associated with the distribution of the underlying choroidal vessels. This suggests that the underlying choroidal vessels may affect choriocapillaris perfusion in pachychoroid eyes.

OCULAR PERFUSION PRESSURE AND CHOROIDAL THICKNESS IN CENTRAL SEROUS CHORIORETINOPATHY AND PIGMENT EPITHELIOPATHY.

PURPOSE: To investigate ocular perfusion pressure (OPP) in patients with central serous chorioretinopathy (CSC) and pigment epitheliopathy (PE). METHODS: In this retrospective study, we included patients with acute idiopathic unilateral CSC and age- and sex-matched normal controls. The patients with CSC were classified into two groups according to the PE presence on their fellow eyes. We compared OPP among CSC patients with or without PE and normal controls. RESULTS: Among a total of 47 patients with CSC, 21 were classified into the PE group and 26 into the non-PE group. The mean OPP (±SD) of CSC and fellow eyes in the PE group (50.02 ± 4.98 and 50.83 ± 4.12 mmHg, respectively) was greater than that in the non-PE group (43.69 ± 6.88 and 44.0 ± 6.57 mmHg, respectively) and normal controls (45.64 ± 8.73 mmHg) (all, P < 0.05). The mean macular choroidal thickness of CSC and fellow eyes in the PE group (344.4 ± 31.8 and 310.1 ± 37.0 µm, respectively) was thicker than that in the non-PE group (318.5 ± 43.8 and 282.8 ± 36.1 µm, respectively) (all, P < 0.05). Greater macular choroidal thickness and higher OPP were associated with PE (P = 0.002 and P = 0.003). CONCLUSION: Forty-five percent of the patients with acute unilateral CSC had PE in their fellow eyes. Increased OPP may influence the development of bilateral CSC characteristics.

Healthcare Utilization and Treatment Patterns in Diabetic Macular Edema in Korea: a Retrospective Chart Review.

BACKGROUND: Limited data exist on real-world treatment patterns for diabetic macular edema (DME) in Korea. In this study, we investigated DME treatment patterns from 2009 to 2014 and the impact of baseline treatment on healthcare resource utilization and visual acuity (VA) outcomes. METHODS: A retrospective cohort chart review of DME patients treated at 11 hospital ophthalmology clinics between January 1, 2012 and December 31, 2013 was conducted. We collected data on demographics, healthcare resource utilization (clinic visits, treatment visits, and visits for ocular investigations), distribution of DME treatments, and VA. RESULTS: Overall, 522 DME patients (men, 55.2%; mean age, 59 years; mean HbA1c [n = 209], 8.4%) with 842 DME eyes were evaluated. For all treatments, healthcare resource utilization was significantly higher during the first 6 months versus months 7-12, year 2, or year 3 (P ≤ 0.001), but was highest for patients whose first treatment was an anti-vascular endothelial growth factor (VEGF) treatment (visits/quarter; anti-VEGF, 1.9; corticosteroids, 1.7; laser, 1.4). Use of macular laser therapy decreased (44% to 8%), whereas use of anti-VEGF injections increased (44% to 69%) during the study period. However, VA improvement was not commensurate with healthcare resource utilization of anti-VEGF treatment (mean VA gain, 2.7 letters). CONCLUSION: A trend toward increasing use of intravitreal anti-VEGF injections for DME treatment was observed in Korea. However, the frequency of dosing and monitoring was lower in clinical practice versus major clinical trials, which may have led to the less-than-favorable improvements in visual outcomes.

Choriocapillaris layer imaging with swept-source optical coherence tomography angiography in lamellar and full-thickness macular hole.

PURPOSE: To present characteristics of choriocapillaris layer imaging with swept-source optical coherence tomography angiography (SS-OCTA) in eyes with macular hole (MH). METHODS: Patients with MH were included. Vascular density of choriocapillaris (VDC) and central flow void areas were obtained using SS-OCTA. Data were compared with age- and gender-matched normal controls. RESULTS: Fifty-one patients with MH and 51 controls were included. Among the 51 patients with MH, 19 had lamellar MH (LMH) and 32 had full-thickness MH (FTMH). While VDC in LMH (79.26 ± 4.06%) was not significantly different from that seen in fellow eyes (79.88 ± 4.28%, P = 0.729) and normal controls (80.53 ± 4.21%, P = 1.000), VDC in surgically closed FTMH (74.60 ± 7.37%) was similar to that of fellow eyes (75.45 ± 7.39%, P = 0.400) but lower than that of controls (78.37 ± 7.13%, P = 0.011). On univariate analysis of 32 patients with unilateral sealed FTMH, VDC was not correlated with basal hole area (P = 0.797) or preoperative area of disrupted ellipsoid zone (P = 0.863). Central flow void was detected in 32 eyes. Mean central flow void area was 0.82 ± 0.84 mm2, which correlated with preoperative area of disrupted ellipsoid zone (P = 0.001). CONCLUSIONS: Choriocapillaris layer imaging using SS-OCTA showed that choriocapillaris in both eyes of patients with unilateral FTMH had different characteristics from eyes with LMH or normal controls. These results suggest that variation in choriocapillaris layer flow is involved in the pathogenesis of MH.

Retinal vascular flow and choroidal thickness in eyes with early age-related macular degeneration with reticular pseudodrusen.

BACKGROUND: To investigate the characteristics of retinal vessels and retinal thickness in eyes with early age-related macular degeneration (AMD) with or without reticular pseudodrusen. METHODS: We retrospectively evaluated the clinical history and optical coherence tomography (OCT) and OCT angiography images of consecutive patients with early AMD. We calculated the retinal vessel densities of the superficial and deep capillary plexus with the ImageJ software (National Institutes of Health, Bethesda, MD, USA) and investigated the relationship with mean retinal thickness and subfoveal choroidal thickness. RESULTS: We included 135 early AMD eyes and classified 60 of them into a reticular pseudodrusen group and 75 into a non-reticular pseudodrusen group. The vascular densities of the superficial and deep capillary plexus in the reticular pseudodrusen group (32.35% ± 3.67 and 26.71% ± 2.88%) were not different from those of the non-reticular pseudodrusen group (33.18% ± 2.2% and % 27.43 ± 1.79%; P = 0.546 and P = 0.318, respectively). The retinal thickness of the reticular pseudodrusen group (287.31 µm ± 24.36 µm) did not differ from that of the non-reticular pseudodrusen group (294.27 µm ± 20.71 µm; P = 0.493), while subfoveal choroidal thickness in the reticular pseudodrusen group (158.13 µm ± 42.53 µm) was lower than that in the non-reticular pseudodrusen group (237.89 µm ± 60.94 µm; P <  0.001). Multivariate analysis revealed that lower vascular density of the superficial capillary plexus and subfoveal choroidal thickness were associated with retinal thinning in reticular pseudodrusen group (P = 0.003 and P = 0.036) and older age was associated with retinal thickness in the non-reticular pseudodrusen group (P = 0.005). CONCLUSIONS: Retinal thinning in early AMD patients with reticular pseudodrusen was accompanied by choroidal and retinal vascular loss, which suggests a possible linkage of retinal thinning with vascular alterations.

Effect of Ambient Light Exposure on Ocular Fatigue during Sleep.

BACKGROUND: To investigate the influence of nocturnal ambient light on visual function and ocular fatigue. METHODS: Sixty healthy subjects (30 men and 30 women) aged 19 through 29 years with no history of ocular disease were recruited. All subjects spent 3 consecutive nights in the sleep laboratory. During the first and second nights, the subjects were not exposed to light during sleep, but during the third night, they were exposed to ambient light, measuring 5 or 10 lux at the eye level, which was randomly allocated with 30 subjects each. The visual function and ocular fatigue were assessed at 7 a.m. on the 3rd and 4th mornings, using best-corrected visual acuity, refractive error, conjunctival hyperemia, tear break-up time, maximal blinking interval, ocular surface temperature, and subjective symptoms reported on a questionnaire. RESULTS: Three men and three women subjects failed to complete the study (4 in the 5 lux; 2 from the 10 lux). For the entire 54 subjects, tear break-up time and maximal blinking interval decreased (P = 0.015; 0.010, respectively), and nasal and temporal conjunctival hyperemia increased significantly after sleep under any ambient light (P < 0.001; 0.021, respectively). Eye tiredness and soreness also increased (P = 0.004; 0.024, respectively). After sleep under 5 lux light, only nasal conjunctival hyperemia increased significantly (P = 0.008). After sleep under 10 lux light, nasal and temporal conjunctival hyperemia, eye tiredness, soreness, difficulty in focusing, and ocular discomfort increased significantly (P < 0.05). CONCLUSION: Nocturnal ambient light exposure increases ocular fatigue. Avoiding ambient light during sleep could be recommended to prevent ocular fatigue.

Effects of a high level of illumination before sleep at night on chorioretinal thickness and ocular biometry.

The choroid is affected by many factors. One of the factors, change in illumination has been suggested to influence choroidal thickness. However, the effects of bright light before sleep at night on the human eye are not well established. The purpose of this study was to investigate the effects of a high level of illumination in the evening on ocular measurements. Twenty-seven men with myopia spent seven consecutive nights in the sleep laboratory. During the first two nights, subjects were exposed to light at 150 lux between 20:00 and midnight. Then, for five consecutive nights, they were exposed to ambient light at 1000 lux between 20:00 and midnight. Ocular parameters and their diurnal variations were compared between the two periods and the effects of a high level of illumination were analyzed. After subjects were exposed to 1000 lux of illumination, axial length increased with borderline significance (p = 0.064). Macular volume and retinal thickness did not change. However, subfoveal choroidal thickness after exposure to 1000 lux of illumination (245.37 ± 52.84 µm) was significantly lower than that after 150 lux of illumination (268.00 ± 57.10 µm), (p < 0.001). Significant diurnal variations were found in mean keratometry (p = 0.039), intraocular pressure (IOP, p = 0.003), ocular perfusion pressure (OPP, p < 0.0001), macular volume (p = 0.019), and subfoveal choroidal thickness (p < 0.0001). A high level of illumination had significant effects on only IOP and OPP (p = 0.027 and 0.017, respectively). Bright light exposure before sleep at an intensity as high as 1000 lux reduced subfoveal choroidal thickness in healthy young men. In conclusion, diurnal variation in choroidal thickness can be affected by bright light exposure before sleep.

Characteristics of retinal vessels in surgically closed macular hole: an optical coherence tomography angiography study.

PURPOSE: The purpose of our study was to investigate characteristics of retinal vessels in eyes with surgically closed macular holes (MH). METHODS: We included patients who underwent surgery for idiopathic MH and a follow-up examination using optical coherence tomography angiography (OCTA). The area of the foveal avascular zone (FAZ) and retinal vascular densities of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were calculated on the postoperative OCTA images and compared with those of age-matched normal controls. RESULTS: Twenty-eight patients with MH and 28 controls were included. Mean postoperative FAZ areas of SCP and DCP (0.317 ± 0.129 mm2 and 0.500 ± 0.174 mm2) were smaller than those of normal controls (0.406 ± 0.131 mm2 and 0.687 ± 0.147 mm2) (P = 0.013 and P < 0.001, respectively). Retinal vascular densities of SCP and DCP in the MH group (32.23 ± 1.45% and 31.85 ± 1.28%) were lower than those of the control group (33.26 ± 1.71% and 33.18 ± 1.89%) (P = 0.019 and P = 0.003, respectively). The retinal vascular densities of SCP and DCP were associated with postoperative mean ganglion cell-inner plexiform layer (GC-IPL) thickness (P = 0.033 and P = 0.035, respectively). The vascular densities were horizontally asymmetric and related to asymmetric distribution of GC-IPL thickness in the MH group. CONCLUSIONS: Surgically closed MH eyes had remodeled retinal vascular patterns, which were related to morphologic changes in the inner retinal layer. The healing process after MH surgery may be involved in asymmetric change in anatomy and hemodynamics of the inner retina.

THE EFFECT OF PHOTOPIGMENT BLEACHING ON FUNDUS AUTOFLUORESCENCE IN ACUTE CENTRAL SEROUS CHORIORETINOPATHY.

PURPOSE: To evaluate the effect of photobleaching on fundus autofluorescence (FAF) images in acute central serous chorioretinopathy. METHODS: We obtained prephotobleaching and postphotobleaching images using an Optomap 200Tx, and photobleaching was induced with a Heidelberg Retina Angiograph 2. Degrees of photobleaching were assessed as grayscale values in Optomap images. Concordances among the three kinds of images were analyzed. Hyper-AF lesions in prephotobleaching images were classified as Type 1 (changed to normal-AF after photobleaching) and Type 2 (unchanged after photobleaching). The FAF composite patterns of central serous chorioretinopathy lesions were classified as diffuse or mottled. Initial and final best-corrected visual acuity, central retinal thickness, and disease duration were compared according to fovea FAF type. RESULTS: Forty-one eyes of 41 patients were analyzed. The lesion brightness of postphotobleaching Optomap FAF showed greater concordance with Heidelberg Retina Angiograph 2 FAF (94.74%) than the prephotobleaching Optomap FAF (80.49%). Eyes with Type 1 fovea had greater initial and final best-corrected visual acuity (20/23 vs. 20/41, 20/21 vs. 20/32, P < 0.0001, P = 0.001, respectively) and shorter disease duration (19.68 ± 12.98 vs. 51.55 ± 44.98 days, P = 0.043) than those with Type 2 fovea. However, eyes with diffuse Type 2 fovea had only lower initial and final best-corrected visual acuity (20/23 vs. 20/45, 20/21 vs. 20/36, P < 0.0001, P < 0.0001, respectively) than those with Type 1 fovea. CONCLUSION: Understanding the photobleaching effect is necessary for the accurate interpretation of FAF images. Furthermore, comparing prephotobleaching and postphotobleaching FAF images may be helpful for estimation of lesion status in central serous chorioretinopathy.