Optical Intensities of Different Compartments of Subretinal Fluid in Acute Vogt-Koyanagi-Harada Disease.

PURPOSE: To investigate the optical intensity in different compartments of subretinal fluid in acute Vogt-Koyanagi-Harada (VKH) disease by using spectral domain optical coherence tomography (SD-OCT). METHODS: Fifty acute VKH eyes and 25 cases with acute central serous chorioretinopathy (CSCR) were included in this retrospective comparative study. The optical intensities of subretinal fluid, vitreous humour and the entire scanned region displayed by SD-OCT were measured with Image J by three independent readers. In the VKH eyes with subretinal septa, the subretinal fluid was segmented into two types of compartments, supra-septa space and sub-septa space. Optical intensity ratios of different compartments of subretinal fluids divided by vitreous humour or the entire scanned region were compared. RESULTS: The measurement of optical intensity was highly reproducible (intraclass correlation coefficient> 0.9). The optical intensity of the supra-septa space divided by the vitreous humour was significantly higher compared to that of sub-septa space in VKH (mean difference = 4.27 ± 5.15, p <0.001). The optical intensity ratio of the supra-septa space (1.14 ± 0.12), but not subsepta space (1.05 ± 0.05) in VKH, was significantly higher compared to that of the subretinal space in VKH without the subretinal septa (1.07 ± 0.08), and the subretinal fluid in CSCR (1.08 ± 0.09). Similar results were found for the optical intensity ratios divided by the entire scan region. CONCLUSION: The optical intensity in the supra-septa space of VKH is higher compared to the sub-septa space in VKH, subretinal space in VKH and CSCR, suggesting that the components in these spaces are different.

Comparison of the optical coherence tomographic characters between acute Vogt-Koyanagi-Harada disease and acute central serous chorioretinopathy.

BACKGROUND: Acute Vogt-Koyanagi-Harada (VKH) disease and acute central serous chorioretinopathy (CSCR) are two common disorders with serous retinal detachment caused by dysfunction of choroid. The purpose of this study is to compare the morphological changes of these two diseases with spectral domain optical coherence tomography (SD-OCT). METHODS: In this retrospective comparative study, the SD-OCT images of 65 eyes with acute VKH and 52 eyes with acute CSCR were reviewed for the presence of subretinal fluid, folds of retinal pigment epithelial (RPE), fluctuation of internal limiting membrane (ILM), subretinal septa, retinal pigment epithelium detachment (PED) and bulge of RPE. The foveal thickness was measured using the manual caliper of OCT software. The characteristics of SD-OCT were compared between two diseases. RESULTS: Subretinal fluid was present in both diseases. Folds of RPE, fluctuation of ILM, subretinal septa were seen only in VKH. Bulge of RPE presented only in CSCR. PED was more common in CSCR than in VKH (44.2% vs 3.1%, p < 0.001). The thickness of fovea and RPE undulation index were significantly greater in VKH compared to that in CSCR (746.7 ± 423.8 vs 444.9 ± 158.8 µm, p < 0.001 and 1.0667 ± 0.0509 vs. 1.0177 ± 0.0023, p = 0.003). CONCLUSION: Our study showed that although VKH and CSCR share similar features on SDOCT, there are characteristic differences between both disease entities.

Longitudinal evaluation of optic disc measurement variability with optical coherence tomography and confocal scanning laser ophthalmoscopy.

PURPOSE: To evaluate and compare the longitudinal variability of optical coherence tomography (OCT) and confocal scanning laser ophthalmoscopy (CSLO) optic disc measurements. METHODS: A total of 25 normal and 50 glaucomatous eyes from 75 subjects were included in the analysis. The optic disc was measured by OCT and CSLO. Three separate measurements collected over an average period of 8.5+/-0.9 months were used to evaluate reproducibility. Univariate and multivariate regression analyses were performed to evaluate the associations between age, refraction, diagnosis (glaucoma or normal), visual field mean deviation, optic disc area, signal strength variance (OCT), optic disc area variance (OCT), image quality SD (CSLO), reference height variance (CSLO), and rim area variability. RESULTS: The intraclass correlation coefficient of optic disc measurements (except for optic disc area) ranged between 0.86 and 0.95 for OCT and between 0.89 and 0.96 for CSLO. The intraclass correlation coefficient for rim area measurement was significantly higher in CSLO (0.95) than that of OCT (0.86, P<0.001). After adjustment for other predictors, optic disc area variance and reference height variance were the most important factors responsible for rim area variability in OCT and CSLO, respectively. CONCLUSIONS: Although both OCT and CSLO have relatively low variability for optic disc measurements, CSLO demonstrates higher measurement reproducibility for rim area compared with OCT. Variations of disc area in OCT and reference height in CSLO constituted a significant proportion of the rim area variability during longitudinal assessment.

Longitudinal variability of optic disc and retinal nerve fiber layer measurements.

PURPOSE: To evaluate the longitudinal variability of optic disc and retinal nerve fiber layer (RNFL) measurements obtained from optical coherence tomography (OCT), scanning laser polarimetry (SLP), and confocal scanning laser ophthalmoscopy (CSLO). METHODS: Forty-five normal and 43 glaucomatous eyes of 88 subjects were analyzed in this longitudinal study. RNFL thickness was measured by OCT (StatusOCT; Carl Zeiss Meditec, Dublin, CA) and SLP (GDx VCC; Carl Zeiss Meditec). Neuroretinal rim area was measured by CSLO (HRT 3; Heidelberg Engineering, GmbH, Dossenheim, Germany). Three separate measurements taken over an average period of 8.8 +/- 1.2 months were used to evaluate measurement variability. Reproducibility coefficient, coefficient of variation, intraclass correlation coefficient (ICC), and sensitivity to change [(97.5 percentile value - 2.5 percentile value)/2 x within-subject standard deviation (Sw)] of the global measures were calculated. The association between RNFL and rim area measurement variability and visual field MD (mean deviation) was evaluated with regression analysis. RESULTS: Low variability was found for global and sectorial rim area and RNFL measurements. The reproducibility coefficient, ICC, and sensitivity to change for OCT average RNFL thickness, GDx VCC TSNIT average, and HRT global rim area were 11.7 microm (95% confidence interval [CI]: 10.5-12.9 microm), 0.97 (0.96-0.98), 10.2 (9.2-11.4); 4.7 microm (4.2-5.1 microm), 0.98 (0.97-0.99), 11.3 (10.2-12.6); and 0.22 mm(2) (0.19-0.24 mm(2)), 0.97 (0.95-0.98), 9.3 (8.4-10.4), respectively. No association was found between OCT (r = 0.010 [95% CI: -0.200-0.219], P = 0.924) and SLP (r = -0.034 [95% CI: -0.241-0.177], P = 0.756) RNFL thickness variances and visual field MD. The association between CSLO rim area variance and visual field MD became insignificant after adjustment for reference height variance. CONCLUSIONS: Longitudinal RNFL and neuroretinal rim measurements obtained with OCT, SLP, and CSLO have low variability. As the measurement variability does not change with the severity of glaucoma, these parameters are useful for assessment of glaucoma progression.

Comparison of macular thickness measurements between time domain and spectral domain optical coherence tomography.

PURPOSE: To compare macular thickness measurements obtained from time domain optical coherence tomography (OCT) and spectral domain OCT and to evaluate their repeatability and agreement. METHODS: Thirty-five healthy normal subjects were included. In one randomly selected eye in each subject, three serial macular measurements were obtained from a time domain OCT (Stratus OCT, Carl Zeiss Meditec, Dublin, CA) and a spectral domain OCT (3D OCT; Topcon, Tokyo, Japan) by an experienced technician in random order. Total and regional macular thicknesses obtained by the two OCTs were compared. Their agreement was examined with Bland-Altman plots. Repeatability (2.77 x within subject SD [Sw]), coefficient of variation (CVw; Sw/overall mean), and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability. RESULTS: Low variability for macular thickness measurements was found in both time domain and spectral domain OCTs. The range of the respective CVw and ICC values were 1.6% to 3.2% and 0.85 to 0.91 for Stratus OCT and 0.6% to 2.4% and 0.92 to 0.99 for 3D OCT. 3D OCT demonstrated better repeatability for total and regional macular thicknesses (all with P

PI3K/akt, JAK/STAT and MEK/ERK pathway inhibition protects retinal ganglion cells via different mechanisms after optic nerve injury.

Recently we unexpectedly found that PI3K/akt, JAK/STAT and MEK/ERK pathway inhibitors enhanced retinal ganglion cell (RGC) survival after optic nerve (ON) axotomy in adult rat, a phenomenon contradictory to conventional belief that these pathways are pro-survival. In this study we showed that: (i) the RGC protection was pathway inhibition-dependent; (ii) inhibition of PI3K/akt and JAK/STAT, but not MEK/ERK, activated macrophages in the eye, (iii) macrophage removal from the eye using clodronate liposomes significantly impeded PI3K/akt and JAK/STAT inhibition-induced RGC survival and axon regeneration whereas it only slightly affected MEK/ERK inhibition-dependent protection; (iv) in the absence of recruited macrophages in the eye, inhibition of PI3K/akt or JAK/STAT did not influence RGC survival; and (v) strong PI3K/akt, JAK/STAT and MEK/ERK pathway activities were located in RGCs but not macrophages after ON injury. In retinal explants, in which supply of blood-derived macrophages is absent, MEK/ERK inhibition promoted RGC survival whereas PI3K/akt or JAK/STAT inhibition had no effect on RGC viability. However, MEK/ERK inhibition exerted opposite effects on the viability of purified adult RGCs at different concentrations in vitro, suggesting that this pathway may be bifunctional depending on the level of pathway activity. Our data thus demonstrate that inhibition of the PI3K/akt or JAK/STAT pathway activated macrophages to facilitate RGC protection after ON injury whereas the two pathways per se did not modulate RGC viability under the injury conditions (in the absence of the pathway activators). In contrast, the MEK/ERK pathway inhibition protected RGCs via macrophage-independent mechanism(s).