Comparison and Correlation of Retinal Sensitivity Between Microperimetry and Standard Automated Perimetry in Low-tension Glaucoma.

PRéCIS:: Our study demonstrated that in low-tension glaucoma (LTG) patients, Microperimeter-3 (MP-3)-derived and Humphrey Field Analyzer (HFA)-derived retinal sensitivities were similar and strongly correlated, allowing the respective data to be interrelated. PURPOSE: To compare and correlate retinal sensitivities obtained by Nidek MP-3 with those obtained from the HFA in eyes with LTG. MATERIALS AND METHODS: In this prospective comparative study, 45 eyes of 24 LTG patients underwent retinal sensitivity assessments using the MP-3 (Nidek Technologies) and the HFA (Carl Zeiss Meditec) at the UCLA-Doheny Eye Center. Global and pointwise retinal sensitivity measurements were compared and correlated between the 2 devices. RESULTS: No statistically significant differences (P=0.85) were noted between the mean retinal sensitivities determined by each device (MP-3: 26.33±4.31 dB; range, 13.05 to 31.60 vs. HFA: 26.42±3.98 dB; range, 17.17 to 30.96), and a strong correlation (r=0.66, P<0.001) was noted for retinal sensitivity measurements. In addition, moderate to strong correlations were observed between the mean retinal sensitivity derived by MP-3 versus HFA-derived mean deviation (r=0.57, P<0.001), as well as, the pattern standard deviation (r=0.67, P<0.001). The intraclass correlation coefficient was excellent (ICC=0.80, 95% confidence interval, 0.63-0.89), while the Bland-Altman analysis showed good agreement between the 2 devices with respect to retinal sensitivity. CONCLUSION: Retinal sensitivity measurements obtained by the MP-3 microperimetry instrument and the standard automated HFA perimeter were similar and highly correlated in patients with LTG. Given the potential benefits of microperimetry technology such as auto-eye-tracking and potentially more precise structure-function correlations, the use of microperimetry to monitor visual function in glaucoma management warrants further consideration.

Correlation between Guttata Severity and Thickness of Descemet's Membrane and the Central Cornea.

Purpose: To characterize and correlate guttata severity, Descemet's membrane thickness (DMT), central cornea thickness (CCT) in corneas with guttae using specular microscopy and spectral-domain optical coherence tomography (SD-OCT) and test the Doheny Image Reading Center (DIRC) specular microscopy-based corneal guttata severity scale. Methods: Forty-nine eyes of 49 patients with guttata and 36 eyes of age-matched of 36 normal controls were enrolled in the study. Three images of the central cornea and four of the peripheral cornea (inferior, superior, nasal and temporal) of each eye were taken using the Konan NSP-9900 specular microscope. A volume scan of the central cornea cross-section was collected on each eye using the Heidelberg Spectralis SD-OCT. The density of endothelial guttata based on specular images was graded on a 0-4 scale, and the Descemet's membrane thickness (DMT) and central corneal thickness (CCT) were manually measured by two trained graders. Results: The DIRC corneal guttata severity scale showed good reproducibility of all corneal endothelial images (weighted Kappa = 0.87). Mean DMT was 16.1 ± 2.4 µm in controls and 25.5 ± 10.9 µm in corneas with guttata (P < 0.001). Mean CCT was 552 ± 26 µm in controls and 603 ± 55 µm in corneas with guttata (P < 0.001). Guttata severity was significantly correlated with both DMT (r = 0.743, P < 0.001) and CCT (r = 0.569, P < 0.001). Age was moderately correlated with DMT (r = 0.472, P = 0.003) and mildly correlated with guttata severity (r = 0.285, P = 0.031), but was not correlated with CCT (r = 0.058, P = 0.681). Guttatta grade 3 corneas displayed an increase in DMT and guttata grade 4 was associated with a significant increase in CCT. Conclusions: The DMT and CCT are increased in corneas with guttata. The higher density of guttae is correlated with increased thickness. Specular microscopy combined with SD-OCT can be used as a good approach to assess the severity of FECD.

Quantitative Analysis of Retinal and Choroidal Vascular Parameters in Patients With Low Tension Glaucoma.

PRéCIS:: By using OCT-A, we observed a reduction of the superficial macular, peripapillary, and optic nerve, as well as the choriocapillaris in eyes with low tension glaucoma, compared with normal controls. PURPOSE: The purpose of this study was to investigate macular and optic disc vascular parameters in patients with low tension glaucoma (LTG) using optical coherence tomography angiography (OCTA). METHODS: In this cross-sectional study, images were prospectively acquired from both eyes of 26 patients with clinically diagnosed LTG and 22 age-matched volunteers with normal healthy eyes using the Zeiss swept-source (SS) OCTA (Plex Elite 9000, Carl Zeiss Meditec). Perfusion density (PD) and vessel length density (VLD) within a 5 mm diameter circle centered over the macula and optic nerve head were analyzed. RESULTS: The final analysis cohort included 49 eyes with LTG and 40 healthy control eyes. Mean age was 60±10 years in the LTG group and 60±17 years in the control group. The LTG group had a statistically significant reduction in PD of the choriocapillaris (CC) compared with normal controls (71.74±8.37% vs. 80.48±3.84%; P<0.001). There was no statistically significant difference in PD between the LTG and control groups for the superficial vascular plexus (SVP), deep capillary plexus (DCP) or the optic nerve head and peripapillary area (ONH+PP) (P>0.05). The LTG group did show statistically significant reductions in VLD compared with normal controls for the SVP (2083.64±153.76 mm/mm vs. 2154.63±144.18 mm/mm; P=0.03) and ONH + PP (1813.76±271.69 mm/mm vs. 1950.23±169.33 mm/mm; P=0.03), whereas the DCP VD was similar between the 2 groups (P>0.05). CONCLUSIONS: Eyes with low tension glaucoma seems to show a lower CC perfusion density, as well as a lower SVP and ONH+PP vessel length density compared to normal eyes.

MACULAR MICROVASCULAR NETWORKS IN HEALTHY PEDIATRIC SUBJECTS.

PURPOSE: To report optical coherence tomography angiography (OCTA) values in healthy pediatric eyes and to identify factors that may modify these values. METHODS: In this prospective observational cross-sectional study, macular OCTA images were acquired from healthy pediatric patients. Main outcome measures were 1) foveal avascular zone (FAZ) area at the level of the superficial retinal capillary plexus (SCP); 2) SCP and deep retinal capillary plexus (DCP) perfusion density (based on the area of vessels); 3) SCP and DCP vessel density (based on a map with vessels of 1-pixel width); and 4) CC perfusion density. Multiple regression analysis was performed to assess the effect of age, sex, ethnicity, refraction, and foveal macular thickness (FMT) on OCTA parameters. RESULTS: Seventy-seven eyes from 52 subjects (23 male and 29 female) were included in analysis. Mean age was 11.1 ± 3.3 years (range = 5.0-17.0 years). Twenty-nine (55.8%) subjects were white, 14 (27.0%) Hispanic, 8 (15.4%) Asian, and 1 (1.8%) African-American. Mean refraction was -0.1 ± 2.4 diopters (D) (range = -5.75 to +9.0 D). Mean FMT was 248.6 ± 18.6 µm. Larger FAZ area was significantly associated with older age (P = 0.014). Furthermore, larger FAZ area was associated with reduced FMT (P < 0.0001). Male sex was associated only with increased SCP perfusion density (P = 0.042). Increased CC perfusion density was associated with younger age (P = 0.022). CONCLUSION: We report data for pediatric OCTA parameters in healthy subjects. Several variables influence the density of macular microvascular networks, and these factors should be considered in the OCTA study of pediatric eye disorders.

Assessment of Corneal Changes Associated with Topical Antiglaucoma Therapy Using in vivo Confocal Microscopy.

PURPOSE: Ocular surface disease (OSD) is highly prevalent in eyes treated with chronic, topical antiglaucoma (A/G) therapy. The purpose of this study was to utilize in vivo confocal microscopy (IVCM) to evaluate the corneal morphology, including characteristics of corneal epithelial cells, presence of epithelial dendritic cells (DCs), and characteristics of subbasal nerve plexus, of eyes under topical A/G therapy versus normal eyes. METHODS: Central corneal images were prospectively captured from 30 eyes of 16 patients under topical A/G therapy (>6 months) and 20 normal control eyes, using IVCM (HRT 3 RCM, Heidelberg, Germany). Demographic data were collected, as well as information on the types and duration of A/G therapy. In addition, OSD index (OSDI) score, tear film breakup time, Schirmer 1 test results, density of epithelial wing cells (WCs) and basal cells (BCs), subbasal nerve features (density, tortuosity, and reflectivity), and presence of DCs were all assessed and recorded by trained Doheny Image Reading Center graders. RESULTS: IVCM findings of 30 glaucomatous eyes and 20 normal control eyes were analyzed. The mean OSDI score was 8.72 in controls and 32.06 in patients under A/G therapy (p = 0.002). Nerve fiber density, nerve fiber reflectivity, and BC density were all decreased in the A/G group (1,789.07 ± 785.70 µm/frame, 2.79 ± 0.83, 6,457.67 ± 692.55 cells/mm2, respectively) as compared to controls (2,815.981 ± 563.77 µm/frame, 3.52 ± 0.50, 7,854.13 ± 1,073.69 cells/mm2, respectively) (p < 0.05), whereas the decrease in WC density was statistically nonsignificant (p = 0.5). Nerve tortuosity and DC density were both significantly greater in the A/G eyes (3.00 ± 0.57, 71.24 ± 61.74 cells/mm2, respectively) compared to controls (2.10 ± 0.42, 34.08 ± 11.70 cells/mm2, respectively) (p < 0.05). Tear film breakup time and Schirmer 1 test results were significantly lower in the A/G group as compared to controls (p < 0.001). CONCLUSIONS: Using IVCM, our study identified significant microstructural alterations in the corneas of eyes treated with topical A/G therapy. In addition, our study also revealed that glaucoma patients treated with topical A/G therapy report significantly higher OSDI scores compared to controls. Thus, IVCM may be a useful tool in providing structural parameters to correlate with the functional OSDI assessments in the evaluation of ocular surface toxicity associated with topical A/G therapy.

Evaluation of Corneal Epithelial Thickness Imaged by High Definition Optical Coherence Tomography in Healthy Eyes.

PURPOSE: To evaluate corneal epithelial thickness (CET) and corneal thickness (CT) in healthy eyes using spectral domain optical coherence tomography. METHODS: Thirty-six healthy eyes were imaged using the Cirrus high-definition (HD)-optical coherence tomography device. The average CET and CT were assessed using Cirrus Review Software within predefined concentric corneal ring-shaped zones. Specific regions of CET (superior, inferior, temporal, nasal, superonasal, inferotemporal, superotemporal, and inferonasal) were also assessed. The difference between zones was compared between males and females. RESULTS: The average CET was 48.3, 47.1, 46.1, and 45.8 µm in the 4 concentric zones (0-2, 2-5, 5-7, and 7-9 mm), respectively (P < 0.001). The average CT was 533.5, 550.8, and 579.4 µm in the 3 zones (0-2, 2-5, and 5-7 mm), respectively (P < 0.001). There was no statistically significant correlation between CET and CT in any of the measured zones. Males had thicker corneas than did females in each of the 3 CT zones (P < 0.05), but CET did not differ significantly. The CET superonasal-inferotemporal in 2.0 to 5.0 mm and CET superotemporal-inferonasal in 5.0- to 7.0-mm zones were significantly thinner in males than in females (-1.15 vs. 0.9 µm, -3.5 vs. -1.9 µm), respectively (P < 0.05). CONCLUSIONS: Optical coherence tomography-based analysis of CET reveals that it is thinner in the periphery, whereas the total corneal thickness is greater. Although total CT seems to be influenced by sex, CET is not. Regional and sex-based variations in CT may need to be considered when assessing corneal and epithelial alterations in the setting of disease.

Analysis of ocular inflammation in anterior chamber-involving uveitis using swept-source anterior segment OCT.

PURPOSE: To evaluate the utility of swept-source (SS) optical coherence tomography (OCT) to objectively analyze the degree of anterior chamber (AC) inflammation. METHODS: Thirty-eight eyes of 32 patients with uveitis and 20 control eyes were enrolled. SS OCT B-scans were obtained, and the number of cells in the B-scans was counted using two methods: (1) manual grading by Point Picker plug-in of Image J ( http://bigwww.epfl.ch/thevenaz/pointpicker/ ) and (2) automated grading by the Image J Particle Analysis algorithm ( http://imagej.net/Particle_Analysis ). The automated and manual AC cell counts were correlated with the Standardization of Uveitis Nomenclature score. RESULTS: The average numbers of AC inflammatory cells counted by the automated method were 8 ± 4.0, 18 ± 3.0, 42 ± 14.0, 81 ± 32.0, 117 ± 57.0, and 275 ± 67.0 cells/mm2 for grades 0, 0.5 + , 1 + , 2 + , 3 + , and 4 + , respectively. For the same clinical categories, the average manual cell counts were 6 ± 4.0, 18 ± 3.0, 34 ± 14.0, 72 ± 32.0, 92 ± 43.0, and 168 ± 65.0 cells/mm2, respectively. Zero cells were detected in the AC of healthy eyes. The automated and manual methods were highly correlated (R = 0.98, p < 0.001) and showed good correlation with the clinical grading (R = 0.88, p < 0.001). A mean AC particle size of 117.4 ± 108.8 µm was obtained by the automated method. CONCLUSIONS: Quantification of the AC cells imaged by SS AS-OCT shows good correlation with categorical clinical severity assessments in uveitis eyes. This approach may provide a more objective method for monitoring uveitis and response to uveitis therapy.

Evaluation of the corneal epithelium in non-Sjögren's and Sjögren's dry eyes: an in vivo confocal microscopy study using HRT III RCM.

BACKGROUND: The corneal epithelium is directly affected in dry eye syndrome. Thus, we attempted to describe the morphological features and evaluate the cellular density within the corneal epithelial layers in patients with non-Sjögren's (NSDE) and Sjögren's syndrome dry eyes (SSDE) by in vivo confocal microscopy (IVCM). METHODS: Central cornea was prospectively imaged by IVCM in 68 clinically diagnosed aqueous tear-deficient dry eyes and 10 healthy age-matched control eyes. Morphological characteristics of corneal epithelial layers and cellular densities were evaluated by four trained graders from the Doheny Eye Institute. RESULTS: Corneal epithelium in dry eyes presents morphological changes such as areas of enlarged and irregular shaped cells. In comparison with controls, the density of superficial epithelial cells was decreased in both the NSDE (P < 0.05) and SSDE groups (P < 0.01); the density of the outer layer of wing cells was smaller but not significantly different in NSDE (P > 0.05), but was lower in the SSDE group (P < 0.01); the density of the inner layer of wing cells was decreased in both the NSDE (P < 0.05) and SSDE groups (P < 0.01) and the density of basal epithelial cells was lower in both the NSDE (P < 0.01) and SSDE groups (P = 0.01). For all cell counts, the interclass correlation coefficient showed good agreement between graders (ICC =0.75 to 0.93). CONCLUSIONS: IVCM represents a reliable technique for examining the corneal epithelial microstructural changes associated with dry eyes, as well as for objectively and reproducibly quantifying cell densities within all corneal epithelial layers.

Comparison of manual & automated analysis methods for corneal endothelial cell density measurements by specular microscopy / Comparación de los métodos de análisis manual y automatizado para medir la densidad celular endotelial corneal mediante microscopio especular

Purpose: To determine the reliability of corneal endothelial cell density (ECD) obtained by automated specular microscopy versus that of validated manual methods and factors that predict such reliability. Methods:Sharp central images from 94 control and 106 glaucomatous eyes were captured with Konan specular microscope NSP-9900. All images were analyzed by trained graders using Konan CellChek Software, employing the fully- and semi-automated methods as well as Center Method. Images with low cell count (input cells number <100) and/or guttata were compared with the Center and Flex-Center Methods. ECDs were compared and absolute error was used to assess variation. The effect on ECD of age, cell count, cell size, and cell size variation was evaluated. Results:No significant difference was observed between the Center and Flex-Center Methods in corneas with guttata (p = 0.48) or low ECD (p = 0.11). No difference (p = 0.32) was observed in ECD of normal controls < 40 yrs old between the fully-automated method and manual Center Method. However, in older controls and glaucomatous eyes, ECD was overestimated by the fully-automated method (p = 0.034) and semi-automated method (p = 0.025) as compared to manual method. Conclusion: Our findings show that automated analysis significantly overestimates ECD in the eyes with high polymegathism and/or large cell size, compared to the manual method. Therefore, we discourage reliance upon the fully-automated method alone to perform specular microscopy analysis, particularly if an accurate ECD value is imperative

Objetivo: Determinar la fiabilidad de la densidad celular endotelial corneal (ECD) obtenida mediante microscopio especular automático frente a métodos manuales validados y factores predictivos de la fiabilidad. Métodos: Se capturaron imágenes nítidas de 94 controles y 106 ojos glaucomatosos con un microscopio especular Konan NSP-9900. Todas las imágenes fueron analizadas por examinadores expertos mediante el software Konan CellChek, utilizando los métodos automatizado total, semiautomático y de centrado. Se compararon las imágenes con bajo recuento celular (número de células <100) y/o córnea guttata con el método de centrado y centrado flexible. Se compararon las ECD, utilizándose el error absoluto para valorar la variación. Se evaluó el efecto de la ECD sobre la edad, el recuento celular, el tamaño celular y la variación del tamaño celular. Resultados: No se observó diferencia significativa entre los métodos de centrado y centrado flexible en las córneas con guttata (p = 0,48) o baja ECD (p = 0,11). No se observó diferencia (p = 0,32) en cuanto a ECD en los controles normales < 40 años entre el método totalmente automatizado y el método de centrado manual. Sin embargo, en los controles mayores y en los ojos glaucomatosos, la ECD fue sobreestimada por el método totalmente automatizado (p = 0,034) y el método semiautomático (p = 0,025), en comparación al método manual. Conclusión: Nuestros hallazgos muestran que los análisis automatizados sobreestiman considerablemente la ECD en los ojos con alto polimegatismo y/o gran tamaño celular, en comparación al método manual. Por tanto, no recomendamos confiar en el método totalmente automatizado por sí solo para realizar estudios mediante microscopio especular, particularmente en casos en que la precisión del valor de ECD sea imperativo

Increased choriocapillaris vessel density in amblyopic children: a case-control study.

PURPOSE: To investigate the choriocapillaris in children with amblyopia, using optical coherence tomography angiography (OCT-A). METHODS: Patients with amblyopia and age-matched controls were prospectively imaged using OCT-A. On OCT-A, the choriocapillaris measures 30 µm starting 31 µm posterior to the retinal pigment epithelium. The section of choriocapillaris under superficial retinal vessels was excluded from analysis to avoid shadowing or projection artifacts. The main outcome measure was choriocapillaris vessel density. Secondary outcome measures were foveal macular thickness and parafoveal macular thickness. RESULTS: A total of 20 eyes of 16 patients with amblyopia and 25 eyes of 25 controls were included. Mean age of amblyopic subjects was 7.6 ± 3.6 years; of controls, 9.3 ± 2.2 years (P = 0.10). Mean refractive error of subjects was 4.3 ± 6.2 D; of controls, 0.0 ± 1.6 D (P = 0.004). Mean choriocapillaris vessel density was 74.8 ± 5.8 in the amblyopic group and 71.1 ± 3.6 in the control group, which was significant even after adjusting for age and refractive error (P = 0.012). There was no difference between groups in foveal macular thickness or parafoveal macular thickness; however, outer parafoveal macular thickness (the inner boundary of the inner nuclear layer to the retinal pigment epithelium outer boundary) was significantly greater in amblyopic eyes than in control eyes, even after adjusting for age and refractive error (203 ± 11 µm and 189 ± 12 µm, resp. [P = 0.014]). CONCLUSIONS: In our study cohort, amblyopic eyes were found to have increased choriocapillaris vessel density as well as a greater outer parafoveal macular thickness, which may be due to alterations in outer retinal maturation.

Reproducibility of Central Corneal Thickness Measurements in Normal Eyes Using the Zeiss Cirrus 5000 HD-OCT and Pentacam HR.

OBJECTIVES: To determine the repeatability and reproducibility of Central Corneal Thickness (CCT) measurements using two different anterior segment imaging modalities, including those obtained with the new anterior segment lens attachments for the Cirrus 5000 HD-OCT. METHODS: A total of 32 eyes from 16 normal volunteers (8 male, 8 female) were enrolled in this prospective study. CCT was measured by the same examiner using the Cirrus 5000 HD-OCT and Pentacam HR. The results of CCT obtained by each method were averaged and compared using t-test analysis. The agreement between the measurement methods was evaluated. Coefficient of Repeatability (CoR) and Intra-Class Correlation Coefficient (ICC) were computed. RESULTS: The mean measurements taken with the Cirrus OCT anterior chamber lens (CCTAC), HD cornea lens (CCTHDC) and pachymetry scans (CCTPach) were 545.35 ± 31.02, 537.87 ± 26.82, and 532.04 ± 29.82 µm, respectively. The mean CCT obtained with the Pentacam (CCTPent) was 545.51 ± 30.71 µm. CCTPent were significantly higher than CCTHDC and CCTPach (p< 0.0001). In contrast, the CCTPent and CCTAC were similar (p=0.87). CCT, as evaluated by the two different instruments, showed excellent correlation (r > 0.98, p< 0.0001) with an ICC > 0.99 (95% CI, 0.97 - 0.99). CoR was the highest for CCTPach (3.7 ± 1.4, 95% CI (3.0- 4.6)). CONCLUSION: CCT measurements from the Cirrus OCT using the new anterior segment lens attachments and the Pentacam HR are highly correlated. This should allow the use of a standardized correction factor if necessary to inter-relate the measurements between the two devices.

Reproducibility of Macular Thickness Measurements in Eyes Affected by Dry Age-Related Macular Degeneration From Two Different SD-OCT Instruments.

BACKGROUND AND OBJECTIVE: To compare macular thickness measurement algorithms of two different spectral-domain optical coherence tomography (SD-OCT) devices in eyes affected by dry age-related macular degeneration (AMD). PATIENTS AND METHODS: Patients with dry AMD and healthy volunteers from the retina clinic of the Doheny Eye Center - UCLA were imaged using two different SD-OCT devices: the RS-3000 Advance (Nidek, Padova, Italy) and the Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA). All patients had been previously diagnosed with drusen or geographic atrophy due to AMD. The commercial instrument software was used to generate the macular retinal thickness measurements, and measurements were compared between devices. RESULTS: Eighty-five diseased eyes from 49 patients and 16 healthy control eyes from eight normal volunteers were included in this study. The macular thickness measurements generated by the two instruments in eyes with AMD differed significantly in mean retinal thickness in the foveal center subfield (257.34 µm ± 51.72 µm using the Nidek OCT vs. 238.20 µm ± 51.89 µm using the Cirrus OCT; P < .001). The mean difference in macular thickness between the two devices was 19.14 µm ± 5.84 µm for diseased eyes and 17.06 µm ± 5.28 µm in normal control eyes, and this was not statistically different between the two groups (P > .05). The macular thickness measurements in diseased eyes, as evaluated by the two different instruments, however, showed excellent correlation (r = 0.99; P < .001), with an intraclass correlation coefficient of 0.99 (95% confidence interval, 0.98-0.99). Post hoc evaluation of cases with larger differences also showed differences in foveal center selection and variabilities in boundary selection with specific pathology. CONCLUSION: Macular thickness measurements provided by the Nidek and Cirrus OCT instruments in eyes with dry AMD are highly correlated but show a consistent difference, which may allow the use of a standard correction factor to be applied to better interrelate measurements between the devices. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:410-415.].

Comparison of manual & automated analysis methods for corneal endothelial cell density measurements by specular microscopy.

PURPOSE: To determine the reliability of corneal endothelial cell density (ECD) obtained by automated specular microscopy versus that of validated manual methods and factors that predict such reliability. METHODS: Sharp central images from 94 control and 106 glaucomatous eyes were captured with Konan specular microscope NSP-9900. All images were analyzed by trained graders using Konan CellChek Software, employing the fully- and semi-automated methods as well as Center Method. Images with low cell count (input cells number <100) and/or guttata were compared with the Center and Flex-Center Methods. ECDs were compared and absolute error was used to assess variation. The effect on ECD of age, cell count, cell size, and cell size variation was evaluated. RESULTS: No significant difference was observed between the Center and Flex-Center Methods in corneas with guttata (p=0.48) or low ECD (p=0.11). No difference (p=0.32) was observed in ECD of normal controls <40 yrs old between the fully-automated method and manual Center Method. However, in older controls and glaucomatous eyes, ECD was overestimated by the fully-automated method (p=0.034) and semi-automated method (p=0.025) as compared to manual method. CONCLUSION: Our findings show that automated analysis significantly overestimates ECD in the eyes with high polymegathism and/or large cell size, compared to the manual method. Therefore, we discourage reliance upon the fully-automated method alone to perform specular microscopy analysis, particularly if an accurate ECD value is imperative.

Comparison of Noncontact Specular and Confocal Microscopy for Evaluation of Corneal Endothelium.

PURPOSE: To compare endothelial cell analysis obtained by noncontact specular and confocal microscopy, using the Konan NSP-9900 and Nidek ConfoScan4 systems, respectively. METHODS: Three groups including 70 healthy eyes, 49 eyes with Fuchs endothelial corneal dystrophy (FECD), and 78 eyes with glaucoma were examined with both the Konan NSP-9900 specular microscope and the Nidek ConfocScan4 confocal microscope. Certified graders at the Doheny Image Reading Center compared corneal endothelial images from both instruments side by side to assess image quality. Endothelial cell density (ECD) measurements were calculated and compared using three different modalities: (1) each instrument's fully automated analysis; (2) each instrument's semiautomatic analysis with grader input; and (3) manual grading methods by certified grader. RESULTS: All normal eyes yielded gradable endothelial images, and most but not all glaucomatous eyes yielded images with high enough image quality to allow grading. In addition, in corneas with severe FECD, poor image quality precluded ECD grading by specular microscopy in 20 eyes (40.8%) but in only 4 (8.2%) confocal images from the same eyes. For the gradable images, the ECD values obtained using the manual grading method from either device were comparable with no statistically significant difference (P>0.05) between specular and confocal devices. Machine-generated ECD values were significantly different from manual results, measuring greater in all cases with specular microscopy. Machine-generated ECD values from confocal microscopy also differed significantly from manual determinations, but not in a consistent direction. Semiautomatic methods for both instruments obtained clinically acceptable ECD values. CONCLUSIONS: Automatic machine-generated ECD measurements differed significantly from manual assessments of corneal endothelium by both specular and confocal microscopy, suggesting that automated results should be used with caution. But ECD values derived manually were comparable between the two devices in both normal and glaucomatous eyes, suggesting that manually graded images from the two instruments can be used interchangeably for reliable ECD measurements. Because of a higher proportion of gradable images, confocal microscopy may be superior to specular microscopy for ECD measurements in FECD.

Corneal features in ocular graft-versus-host disease by in vivo confocal microscopy.

PURPOSE: The purpose of our study was to determine the morphological features of the corneal epithelial layers, sub-basal nerve plexus and anterior stroma in patients with ocular graft-versus-host disease (oGVHD) compared to non-GVHD dry eyes and normal controls, using in vivo confocal microscopy (IVCM). METHODS: IVCM was used to capture central cornea images from eight volunteers with normal healthy eyes, ten patients with non-GVHD dry eye syndrome (DES) and 15 patients with clinically diagnosed oGVHD, in a cross-sectional study. Morphological changes of the corneal epithelial layers and anterior stroma, characteristics of corneal nerves and presence of dendritic cells (DCs) were then evaluated. RESULTS: IVCM images obtained from 66 eyes were analyzed. The density of superficial epithelial cells was 636.07 ± 101.05 cells/mm2 in the oGVHD group, 827 ± 99.62 cells/mm2 in the DES group and 1277.2 ± 121.42 cells/mm2 in the control group (P < 0.001). The density of wing cells was 4499.79 ± 976.36 cells/mm2 in the oGVHD group, 4662.85 ± 319.72 cells/mm2 in DES group and 6556.38 ± 503.99 cells/mm2 in the control group (p < 0.001). The density of basal cells was 7850.93 ± 723.51 cells/mm2 in the oGVHD group, 8570 ± 913.32 cells/mm2 in DES group and 9759.8 ± 251.99 cells/mm2 in the control group (p < 0.01). The density of nerve fibers was 11.22 ± 5.46 mm/mm2 in the oGVHD group, 14.50 ± 4.27 mm/mm2 in DES group and 19.56 ± 4.75 mm/mm2 in the control group (p < 0.01). The DC density was 67.88 ± 71.82 cells/mm2 in the oGVHD group, 40.06 ± 31.95 cells/mm2 in the DES group and 29.45 ± 8.1 cells/mm2 in the control group (P > 0.05). Visible networks of activated keratocytes were seen in the anterior stroma of eyes with oGVHD and DES, but not in normal controls. CONCLUSIONS: IVCM revealed distinct microstructural changes in the corneas of patients with oGVHD and DES, similar between the two groups. Our findings suggest implications for use of IVCM to evaluate and monitor patients with dry eyes associated or not with GVHD.

Comparison of the Center and Flex-Center Methods of Corneal Endothelial Cell Analysis in the Presence of Guttae.

PURPOSE: To compare endothelial cell analysis by the center and flex-center methods in corneas with guttae of differing severity and to determine the minimum countable cell number for using only the flex-center method. METHODS: Forty-seven eyes with corneal guttae and 50 age-matched normal controls were enrolled in the study. Three images were captured in each central cornea with the noncontact specular microscope. Endothelial cell density (ECD), coefficient of variation (CV), and percentage of hexagonal cells (HEX) were analyzed by trained graders, using both center and flex-center methods. RESULTS: Consistent ECD and HEX values were obtained in normal eyes by both methods (P > 0.05). In corneas with guttae, ECD values obtained by the center method were 2.4% higher than those obtained with the flex-center method (P < 0.001). ECD values derived by both methods disagreed only when <30 cells were identified or <20 cells were analyzed. CV values obtained by the center method were 17.1% (P < 0.001) lower than those obtained by the flex-center method. HEX values obtained with both methods (P > 0.05) agreed. Regardless of guttae density, the ECD, CV, and HEX values of 3 images of each eye were in agreement (P > 0.05). CONCLUSIONS: In corneas with guttae, both center and flex-center methods can reliably determine ECD. Although current practice recommends the center method when at least 100 cells can be counted, our study suggests that the center method can provide a reliable ECD value when there are ≥30 contiguous countable cells in a central cornea endothelial image. The flex-center method is recommended when <30 contiguous cells are identified.

Correlation between corneal innervation and inflammation evaluated with confocal microscopy and symptomatology in patients with dry eye syndromes: a preliminary study.

PURPOSE: To evaluate corneal innervation and inflammatory cell infiltration using in vivo confocal microscopy (IVCM) and to correlate these findings with subjective symptoms of dry eye, as measured by the Ocular Surface Disease Index (OSDI) in patients with non-Sjögren's (NSDE) and Sjögren's syndrome dry eyes (SSDE). METHODS: Central corneal images were prospectively captured from 10 age-matched healthy control eyes, 24 eyes with clinically diagnosed NSDE and 44 eyes with clinically diagnosed SSDE, using IVCM (HRT III RCM). Density, tortuosity and reflectivity of corneal nerves, presence of inflammatory dendritic cells (DCs) and OSDI scores were evaluated. RESULTS: Images obtained by IVCM from 78 eyes were analyzed. The density of nerve fibers was 1562 ± 996 µm/frame in the SSDE group, 2150 ± 1015 µm/frame in the NSDE group and 2725 ± 687 µm/frame in the control group (P < 0.05, ANOVA). In comparison to the control group, the density of nerve fibers was decreased in the SSDE (P < 0.001) and the NSDE groups (P = 0.06), with increased nerve tortuosity and decreased reflectivity in both groups (both P < 0.05). The density of DCs was 71.65 ± 72.54 cells/mm2 in the SSDE group, 40.33 ± 31.63 cells/mm2 in the NSDE group and 27.53 ± 5.58 cells/mm2 in the control group (P < 0.05, ANOVA). In comparison to the control group, the density of DCs was increased in the SSDE (P < 0.001) and the NSDE groups (P = 0.07). Significant correlations were found between the nerve density and DC density (r = -0.57, P < 0.001), between the nerve density and OSDI scores (r = -0.91, P < 0.001) and between the nerve reflectivity and OSDI scores (r = -0.75, P < 0.001). CONCLUSIONS: The corneas of eyes affected with NSDE and SSDE are characterized by alterations in corneal innervation and infiltration of inflammatory DCs. Corneal nerve density and reflectivity are correlated with severity of subjective dry eye symptoms, as measured by OSDI score.

Quantitative Comparison of Swept-Source and Spectral-Domain OCT Angiography in Healthy Eyes.

BACKGROUND AND OBJECTIVE: To compare macular vessel density (VD) and foveal avascular zone (FAZ) area in healthy individuals using two different optical coherence tomography angiography (OCTA) devices. PATIENTS AND METHODS: In this prospective, comparative study, 25 eyes of 14 healthy subjects underwent fovea-centered 3 mm × 3 mm OCTA-imaging using the Triton (Topcon, Tokyo, Japan) and RS-3000 (Nidek, Gamagori, Japan) OCTA devices. Superficial and deep retinal layers (SRL/DRL) and FAZ were manually graded after threshold standardization to determine macular VD and area of the FAZ. RESULTS: The mean difference in the VD between the two devices was 0.105 and 0.096, and the coefficient of variation (CV) was 19.59% and 16.90% for the SRL and DRL, respectively. After skeletonization of vessels to remove variation related to vessel width, the mean difference was 0.174 mm-1 and 0.516 mm-1, and the CV was 3.49% and 1.07% for SRL and DRL, respectively. The mean difference of FAZ area was 0.001 mm2 and 0.010 mm2 in the SRL and DRL, respectively, and the CV was 2.17% and 5.74% for the SRL and DRL, respectively. CONCLUSION: Macular VD using skeletonized mapping and FAZ area in SRL and DRL were statistically similar between the two devices, demonstrating a possible comparison of quantitative values between different OCTA devices. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:385-391.].

Characterization of Corneal Involvement in Eyes With Mucous Membrane Pemphigoid by In Vivo Confocal Microscopy.

PURPOSE: To describe the morphological features of the corneal epithelial layers, subbasal nerve plexus, stroma, and endothelium in patients with mucous membrane pemphigoid (MMP) as shown by in vivo confocal microscopy (IVCM). METHODS: Central corneal images were captured from 10 healthy age-matched control eyes and 30 eyes with clinically diagnosed MMP by in vivo laser scanning confocal microscopy (HRT III RCM). Morphological changes of the corneal epithelial layers, stroma, and endothelium, characteristics of corneal nerves, and presence of inflammatory dendritic cells (DCs) were evaluated. RESULTS: Images obtained by IVCM from 40 eyes were analyzed. The eyes with MMP were divided into 2 groups based on clinical staging: 16 eyes with end-stage MMP and 14 eyes with non-end-stage MMP. Compared with controls, IVCM in eyes with end-stage MMP displayed severe conjunctivalization and neovascularization of the cornea, with otherwise limited identifiable cellular or structural elements. Those with non-end-stage MMP showed metaplasia of the corneal epithelial layers, presence of hyperreflective cells similar to conjunctival cells, intraepithelial defects, fibrosis of anterior stroma, and hyperreflective endothelial deposits. Images of the subbasal nerve plexus demonstrate significant reduction in density (1251.3 ± 806.9 µm/frame vs. 2688.8 ± 607.33 µm/frame, P < 0.001), increased tortuosity (2.76 ± 0.6 vs. 2.3 ± 0.42, not significant), decreased reflectivity (2.73 ± 0.4 vs. 3.46 ± 0.52, P < 0.01), and increased density of DCs (115 ± 88 cells/mm vs. 43.9 ± 28.14 cells/mm, P < 0.05) in MMP-affected eyes compared with controls. CONCLUSIONS: IVCM reveals profound and variable microstructural changes in the corneas of patients with MMP compared with normal controls. Our study demonstrated decreased corneal nerve density and elevated DC density in eyes with non-end-stage MMP compared with normal controls. Frequent scarring, conjunctivalization, and neovascularization observed in eyes with end-stage MMP preclude recognition by IVCM of the morphologic architecture of the corneal layers. Our findings suggest implications for using IVCM to evaluate and monitor patients with MMP.

Correlation Between Mesopic Retinal Sensitivity and Optical Coherence Tomographic Metrics of the Outer Retina in Patients With Non-Atrophic Dry Age-Related Macular Degeneration.

BACKGROUND AND OBJECTIVE: To determine the correlation between mesopic retinal sensitivity and optical coherence tomographic metrics of the outer retina in patients with intermediate age-related macular degeneration (AMD). PATIENTS AND METHODS: Participants with nonatrophic dry AMD underwent mesopic MP-3 microperimetry (Nidek, Padova, Italy) and both Nidek and Cirrus (Carl Zeiss Meditec, Dublin, CA) spectral-domain optical coherence tomography (SD-OCT). The volume of the outer retinal layers was measured on the Nidek SD-OCT scans using the automatic segmentation algorithm of Navis-EX software. In addition, drusen area and volume within a 5-mm circle centered on the fovea were determined using the Cirrus Advanced RPE Analysis Tool. The mean retinal sensitivity at 8° and 10° of fixation (5-mm and 6-mm circles) was calculated for every eye. The correlation between retinal sensitivity and patient age, outer retinal layer volume, drusen area, and drusen volume was assessed. RESULTS: Thirty-seven eyes from 25 patients with non-atrophic dry AMD were included in the study. The mean age of the patients was 76 years ± 9 years. The mean sensitivity across the whole tested retinal area was 24.9 dB ± 2.4 dB, with a sensitivity of 25.1 dB ± 2.4 dB within the central 5-mm circle. Drusen area within the central 5-mm circle was 0.7 mm2 ± 0.89 mm2 with a drusen volume of 0.03 mm3 ± 0.04 mm3. Retinal pigment epithelium and photoreceptor outer segment (RPE + OS) volume was 1.96 mm3 ± 0.1 mm3, and outer nuclear layer (ONL) volume was 1.91 mm3 ± 0.17 mm3. There was a significant correlation between RPE + OS volume and retinal sensitivity, as well as between patients' age and retinal sensitivity. There was no significant correlation between drusen area or volume and retinal sensitivity, nor between ONL volume and retinal sensitivity. CONCLUSION: In eyes with nonatrophic AMD, retinal sensitivity is correlated with the RPE + OS volume, but not the ONL volume or the area or volume of drusen. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:312-318.].