Evaluation of ocular microvascular characteristics in smokers and patients with chronic obstructive pulmonary disease using an optical coherence tomography angiography.

PURPOSE: To investigate retinal microvascular changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) and to compare these values with those of smokers and healthy non-smokers. METHODS: This study was performed on 38 eyes of 38 patients with COPD, 30 eyes of 30 smokers, and 31 eyes of 31 healthy non-smokers. Foveal avascular zone (FAZ) area, superficial (SCP) and deep (DCP) capillary plexus (whole image, fovea, parafovea, and perifovea) and radial peripapillary capillary (RPC) vessel densities (whole image, peripapillary, and inside disc) were evaluated via OCTA device (Optovue, Fremont, CA, USA). The forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) ratio and FEV1 values of patients with COPD were recorded. RESULTS: There were statistically similar values in smoking pack-years between the smoker and COPD groups (p = 0.059). Entire SCP and DCP vessel densities were significantly different among the all groups (p < 0.05); for these parameters, the control group had the highest and the COPD group had the lowest vessel density values. Significantly decreased RPC vessel densities in all regions were detected in the COPD group compared with the other groups. Multiple regression analysis showed significant positive correlations between the FEV1 and the SCP, DCP, and RPC vessel densities (for all, p < 0.05). CONCLUSIONS: This study detected lower vessel densities in patients with COPD than in smokers and healthy controls and reported decreased vessel density measurements with increasing COPD severity. COPD patients with or without a history of smoking may benefit from higher prioritization in terms of ophthalmic screening to prevent ocular complications.

Long-term Effects of Uncomplicated Traumatic Hyphema on Corneal and Lenticular Clarity.

PURPOSE: To evaluate the long-term effects of uncomplicated traumatic hyphema on endothelial morphology, anterior segment structure, and corneal and lenticular densitometry. METHODS: In this retrospective comparative study, eyes with a history of uncomplicated traumatic hyphema were compared with the healthy contralateral unaffected eyes. The corneal endothelial cell properties were captured using specular microscopy. Anterior segment analysis, corneal densitometry (12-mm corneal diameter), and lens densitometry measurements were performed using the Pentacam imaging system. RESULTS: Measurements were obtained at a mean follow-up of 49.5 ± 15.8 months after injury. The average endothelial cell density was significantly lower in the study group than in the control group (2,506.6 ± 294.0 cells/mm² vs. 2,665.7 ± 195.0 cells/mm², p = 0.020). There was no difference between the groups in respect of polymegathism and pleomorphism (p = 0.061 and p = 0.558, respectively). All the investigated corneal tomographic and angle parameters were similar in both groups (all p > 0.05). The corneal densitometry values in all concentric zones and layers showed no statistically significant difference between the groups (p > 0.05 for all). The lens zone 1 densitometry value was significantly higher in the study group than in the control group (9.6% ± 1.1% vs. 8.9% ± 1.2%, p = 0.031). No difference was observed in zone 2 and 3 (p = 0.170 and p = 0.322, respectively). The degree of hyphema was not correlated with endothelial cell and lenticular clarity loss (p = 0.087 and p = 0.294, respectively). CONCLUSIONS: Even if traumatic hyphema is not complicated, long-term outcomes indicate endothelial cell loss and increased lenticular density.

Comparison of radial peripapillary capillary density results of individuals with and without Helicobacter pylori infection.

PURPOSE: To evaluate the radial peripapillary capillary density using optical coherence tomography angiography in patients with and without Helicobacter pylori infection. METHODS: This prospective, cross-sectional study comprised 52 patients (52 eyes: Group 1) and 38 patients (38 eyes: Group 2) with and without H. pylori infections, respectively. The radial peripapillary capillary density and retinal nerve fiber layer thickness in 4 equal quadrants and 2 equal hemispheres in the peripapillary region were calculated using optical coherence tomography angiography. The optic nerve head parameters of the patients were also assessed. RESULTS: The groups were similar in terms of age, gender, and the optic nerve head parameters. The radial peripapillary capillary densities in the superior hemisphere and quadrant were significantly lower in Group 1 than in Group 2 (p=0.039 and p=0.028, respectively) and were positively correlated with the superior hemisphere's retinal nerve fiber layer thickness (p<0.001 and p<0.001, respectively). Similarly, the radial peripapillary capillary densities in the inferior hemisphere and quadrant were also significantly lower in Group 1 compared to Group 2 (p=0.03 and p=0.017, respectively) and were positively correlated with the inferior hemisphere's retinal nerve fiber layer thickness (p<0.001 and p<0.001, respectively). The retinal nerve fiber layer thickness in the nasal and temporal quadrants were significantly decreased in Group 1 when compared to Group 2 (p=0.013 and p=0.022) and were positively correlated with the corresponding radial peripapillary capillary densities of the 2 quadrants (p=0.002 and p=0.022). CONCLUSION: The decreased radial peripapillary capillary density in the H. pylori-positive patients suggests that H. pylori may play a role in the etiopathogenesis of glaucoma.

Long-term evaluation of posterior corneal surface parameters after accelerated corneal cross-linking with a comparison with uncross-linked keratoconic eyes.

PURPOSE: To evaluate the 36 months changes in posterior corneal surface parameters in keratoconic eyes after accelerated corneal cross-linking and to compare the data with uncross-linked progressive and non-progressive keratoconic eyes. METHODS: Thirty five cross-linked, 30 uncross-linked progressive, and 30 uncross-linked non-progressive keratoconic eyes were included. Maximum keratometry (Kmax), thinnest pachymetry, minimum radius of curvature back (Rminback), asphericity back, posterior elevation and corneal densitometry, back corneal higher order aberrations (HOAs), back surface deviation (Db), final D, posterior radius of curvature (PRC) and 'B' unit values were recorded at baseline and at the 12, 24, 36 months follow-up. Data were analyzed with repeated measures ANOVA and paired t-tests. RESULTS: Kmax and thinnest pachymetry were significantly changed in the cross-linked and progressive uncross-linked groups. Rminback, asphericity back, and HOAs did not change in either group. Total posterior corneal densitometry improved; posterior elevation, Db and B unit worsened in the cross-linked group and did not change in the uncross-linked groups. PRC and final D worsened in the cross-linked and progressive uncross-linked groups, and did not change in the non-progressive group. CONCLUSION: Despite a decreased Kmax, the posterior corneal surface parameters, posterior elevation values were determined to have significantly worsened in the cross-linked group and this increase was higher than in progressive uncross-linked eyes.

Comparison of radial peripapillary capillary density results of individuals with and without Helicobacter pylori infection / Comparação dos resultados da densidade capilar peripapilar radial de indivíduos com e sem infecção por Helicobacter pylori

ABSTRACT Purpose: To evaluate the radial peripapillary capillary density using optical coherence tomography angiography in patients with and without Helicobacter pylori infection. Methods: This prospective, cross-sectional study comprised 52 patients (52 eyes: Group 1) and 38 patients (38 eyes: Group 2) with and without H. pylori infections, respectively. The radial peripapillary capillary density and retinal nerve fiber layer thickness in 4 equal quadrants and 2 equal hemispheres in the peripapillary region were calculated using optical coherence tomography angiography. The optic nerve head parameters of the patients were also assessed. Results: The groups were similar in terms of age, gender, and the optic nerve head parameters. The radial peripapillary capillary densities in the superior hemisphere and quadrant were significantly lower in Group 1 than in Group 2 (p=0.039 and p=0.028, respectively) and were positively correlated with the superior hemisphere's retinal nerve fiber layer thickness (p<0.001 and p<0.001, respectively). Similarly, the radial peripapillary capillary densities in the inferior hemisphere and quadrant were also significantly lower in Group 1 compared to Group 2 (p=0.03 and p=0.017, respectively) and were positively correlated with the inferior hemisphere's retinal nerve fiber layer thickness (p<0.001 and p<0.001, respectively). The retinal nerve fiber layer thickness in the nasal and temporal quadrants were significantly decreased in Group 1 when compared to Group 2 (p=0.013 and p=0.022) and were positively correlated with the corresponding radial peripapillary capillary densities of the 2 quadrants (p=0.002 and p=0.022). Conclusion: The decreased radial peripapillary capillary density in the H. pylori-positive patients suggests that H. pylori may play a role in the etiopathogenesis of glaucoma.

RESUMO Objetivos: Avaliar a densidade capilar peripapilar radial de pacientes com e sem infecção por Helicobacter pylori (H. pylori) por meio de angiotomografia de coerência óptica. Métodos: Cinquenta e dois olhos de 52 pacientes com infecção por H. pylori (Grupo 1) e 38 olhos de 38 pacientes sem infecções por H. pylori (Grupo 2) foram incluídos neste estudo prospectivo e transversal. A densidade capilar peripapilar radial (%) e a espessura da camada de fibra nervosa retiniana (μm) em 4 setores iguais e 2 hemisférios iguais foram calculados automaticamente na região peripapilar por angiotomografia de coerência óptica. Os parâmetros da cabeça do nervo óptico dos pacientes também foram avaliados. Resultados: Os grupos foram semelhantes em relação aos parâmetros: idade, sexo e cabeça do nervo óptico. As densidades capilares peripapilares radiais no hemisfério superior, hemisfério inferior, quadrante superior e quadrante inferior foram significativamente menores no Grupo 1 do que no Grupo 2 (p=0,039, p=0,03, p=0,028 e p=0,017 respectivamente). As densidades capilares peripapilares radiais, tanto no hemisfério superior quanto no quadrante superior, foram correlacionadas positivamente com a espessura da camada de fibra nervosa da retina do hemisfério superior (p<0,001 e p<0,001). As densidades capilares peripapilares radiais no hemisfério inferior e no quadrante inferior foram positivamente correlacionadas com a espessura da camada do nervo retiniano do hemisfério inferior (p<0,001 e p<0,001). A espessura da camada da fibra nervosa retiniana nos quadrantes nasal e temporal diminuiu significativamente no Grupo 1 quando comparado ao Grupo 2 (p=0,013 e p=0,022), e esses valores foram positivamente correlacionados com as densidades capilares peripapilares radiais correspondentes nos quadrantes nasal e temporal (p=0,002 e p=0,022). Conclusão: A diminuição das densidades capilares peripapilares radiais nos olhos de indivíduos positivos para H. pylori sugere que H. pylori pode desempenhar um papel na etiopatogenia do glaucoma.

Evaluation of the radial peripapillary capillary density in unilateral branch retinal vein occlusion and the unaffected fellow eyes.

Background: Given that unilateral branch retinal vein occlusion (BRVO) and glaucoma share common systemic vascular risk factors, the fellow eyes of patients with BRVO may be at increased risk of glaucoma. Objectives: To analyze the radial peripapillary capillary density (RPCD) in eyes with unilateral BRVO and their unaffected fellow eyes using optical coherence tomography angiography (OCTA). Design: Cross-sectional, prospective study. Methods: The study included 120 eyes of 80 patients: 40 affected eyes of BRVO, 40 fellow eyes of BRVO, and 40 control eyes. The RPCD, retinal nerve fiber layer thickness (RNFLT) were analyzed using OCTA. Results: RPCDs in the whole image, peripapillary region, all the hemispheres, and quadrants were statistically lower in the affected eyes than in both the fellow and control eyes (p < 0.05 for all). RPCD values in the whole image and the peripapillary region were significantly lower in the fellow eyes than in the control eyes (p = 0.013, and p = 0.021, respectively). RNFLTs in the peripapillary region, inferior hemisphere and inferior quadrant were significantly lower in the affected eyes than in the control eyes (p < 0.05 for all). No significant differences were detected between the fellow eyes and the control eyes in term of RNFLT values in any regions (p > 0.05 for all). Conclusion: Lower RPCD values despite similar RNFLT values were observed in the fellow eyes of patients with unilateral BRVO compared with healthy controls. These results may indicate the shared vascular mechanisms and risk factors that account for the development of BRVO and glaucoma.

Retinal Microcirculation Alterations in Microalbuminuric Diabetic Patients With and Without Retinopathy.

PURPOSE: To investigate the effect of microalbuminuria (MA) on superficial vessel density (SVD), deep vessel density (DVD), and choriocapillaris vessel density (CVD) in type-2 diabetic patients. METHODS: Twenty patients without diabetic retinopathy (DR) and MA (group 1), 20 patients without DR but with MA (group 2) and 30 patients with mild DR and MA (group 3) were enrolled in this prospective and cross-sectional study. SVD, DVD, and CVD of all patients were screened with optical coherence tomography angiography (OCTA). The relationships between these values and age, diabetes duration and metabolic parameters were also evaluated. RESULTS: The whole macular SVD value was 50.15 ± 4.52 in group 1 and 47.81 ± 4.12 in group 2 (p = .04). The whole macular DVD value was 47.66 ± 2.76 in group 1, 44.37 ± 3.39 in group 3 (p = .02). Parafoveal DVD value was 52.58 ± 3.47 in group 1, 51.84 ± 2.23 in group 2, and 49.23 ± 3.38 in group 3 (p G1&3 = .001, p G2&3 = .02). Perifoveal DVD value was 47.92 ± 3.30 in group 1, 43.96 ± 4.19 in group 2, and 42.85 ± 2.98 in group 3 (p G1&2 = .02 and p G1&3 < .001). There were inverse correlations between diabetes duration, urea, creatinine, albumin, urinary sodium and some DVD values (p < .05, for all). Also, there were inverse correlations between parafoveal and perifoveal DVD values and MA (p = .002 and p = .031). Additionally, inverse correlations were determined between diabetes duration, creatinine, urea, serum Na and some CVD values (p < .05 for all).Conclusion: Decreased SVD and DVD values measured by OCTA in type-2 diabetic patients, whether they have mild DR or not, may be associated with MA causing early retinal microvascular changes.

Association between disorganization of the retinal inner layers and capillary nonperfusion area in patients with retinal vein occlusion / Associação entre a desorganização das camadas internas da retina e areas sem perfusão capilar em pacientes com oclusão de veia retiniana

ABSTRACT Purpose: To determine the correlation between the extent of disorganization of the retinal inner layers (a parameter of spectral domain optical coherence tomography) and optical coherence tomography angiography parameters in eyes with center-involved macular edema associated with retinal vein occlusion. Methods: This retrospective observational study included 34 eyes of 34 patients with newly diagnosed macular edema associated with retinal vein occlusion and evidence of center-involved macular edema. Optical coherence tomography angiography and spectral domain optical coherence tomography were evaluated after resolution of the macular edema. Disorganization of the retinal inner layers was determined via spectral domain optical coherence tomography and optical coherence tomography angiography parameters, including foveal avascular zone area in the superficial capillary plexus and capillary nonperfusion areas, foveal avascular zone area in full retinal vasculature, foveal avascular zone perimeter, acircularity index of the foveal avascular zone, and foveal density. Results: The mean disorganization of the retinal inner layers extent was 512.72 ± 238.47 microns, and the mean capillary nonperfusion area was 4.98 ± 2.85 mm2. There was a positive correlation between the extent of disorganization of the retinal inner layers and capillary nonperfusion area (p<0.001, r=0.901). Greater extent of disorganization of the retinal inner layers and the capillary nonperfusion area was correlated with wider foveal avascular zone area (p=0.014 and p=0.036, respectively) in the superficial capillary plexus and decreased foveal density (vessel density in 300 microns around the foveal avascular zone) (p=0.031 and p=0.022, respectively). These parameters were also correlated with decreased vessel density in both the superficial capillary plexus and deep capillary plexus in the parafoveal and peri­foveal regions (p<0.05 for all). Conclusions: Disorganization of the retinal inner layers appears to be a correlated biomarker of capillary ischemia in retinal vein occlusion. The extent of disorganization of the retinal inner layers was strongly correlated with the capillary nonperfusion area. This may support the notion that the extent of disorganization of the retinal inner layers can be used as an easily obtainable and crucial surrogate marker of capillary ischemia.

RESUMO Objetivo: Determinar a correlação entre a ex­tensão da desorganização das camadas internas da retina, que constitui um parâmetro da tomografia de coerência óptica de domínio espectral, e os parâmetros da angiografia por tomografia de coerência óptica em olhos com edema macular com envolvimento central associado à oclusão da veia retiniana. Métodos: Este estudo retrospectivo observacional incluiu 34 olhos de 34 pacientes com edema macular recém-diag­nosticado associado à oclusão da veia retiniana e com evidência de edema macular com envolvimento central. Após a resolução do edema macular, foram avaliadas a tomografia de coerência óptica de domínio espectral e a angiografia por tomografia de coerência óptica. A desorganização das camadas internas da retina foi determinada através de parâmetros da tomografia de coerência óptica de domínio espectral e da angiografia por tomografia de coerência óptica, incluindo a área da zona avascular foveal no plexo capilar superficial e nas regiões sem perfusão capilar, a área da zona avascular foveal na vascularização total da retina, o perímetro da zona avascular foveal, o índice de não circularidade da zona avascular foveal e a densidade foveal. Resultados: A extensão média da desorganização das camadas internas da retina foi de 512,72 ± 238,47 mm e a área média da região sem perfusão capilar foi de 4,98 ± 2,85 mm2. Houve uma correlação positiva entre a extensão da desorganização das camadas internas da retina e a área da região sem perfusão capilar (p<0,001, r=0,901). Maior extensão da desorganização das camadas internas da retina e da região sem perfusão capilar correlacionaram-se a uma área maior da zona avascular foveal (respectivamente, p=0,014 e p=0,036) no plexo capilar superficial e a uma menor densidade foveal (a densidade vascular nos 300 μm à volta da zona avascular foveal; respectivamente, p=0,031 e p=0,022), e também se correlacionaram a uma menor densidade vascular tanto no plexo capilar superficial como no profundo, nas regiões parafoveal e perifoveal (p<0,05 em todas as correlações). Conclusão: A desorganização das camadas internas da retina parece ser um biomarcador correlacionado com a isquemia capilar na oclusão da veia retiniana. O fato de que a extensão dessa desorganização se correlacionou fortemente com a área sem perfusão capilar sugere o uso da extensão da desorganização das camadas internas da retina como um marcador substituto de isquemia capilar, sendo este um marcador importante e facilmente obtido.

Densitometric analysis of cornea in patients with neovascular age-related macular degeneration after intravitreal aflibercept loading dose.

PURPOSE: To evaluate the anatomic changes in the cornea and anterior segment following intravitreal aflibercept loading dose for neovascular age-related macular degeneration. METHODS: The study included 40 eyes of 40 patients with neovascular age-related macular degeneration. Each patient underwent a loading dose of one injection per month for three consecutive doses of aflibercept (0.05 ml/2 mg). Before and after the loading dose, a record was made for each patient of corneal topography, anterior segment, corneal densitometry, and lens densitometry parameters with the Pentacam HR and specular microscopy parameters with a non-contact specular microscope. The data before and after the aflibercept loading dose were compared. RESULTS: Corneal densitometry parameters in the 0- to 2-mm and 2- to 6-mm concentric zones of the posterior layer were significantly higher after the loading dose compared with baseline (p = 0.03, p = 0.04, respectively). Corneal densitometry parameters of the anterior, central, and total corneal layer in the 10- to 12-mm concentric zone were also significantly higher after the loading dose compared with baseline (p = 0.009, p = 0.02, and p = 0.007, respectively). No significant changes were determined in respect of corneal topography, anterior segment, lens densitometry, and specular microscopy parameters (p > 0.05 for all). CONCLUSION: The aflibercept loading dose caused slightly increased densitometric values in some corneal regions while it did not affect the corneal topography, anterior segment, lens densitometry, and specular microscopy parameters.

Comparative Evaluation of Central Corneal Thickness in Cross-Linked Keratoconic Eyes.

PURPOSE: To compare the central corneal thickness (CCT) measurements measured by using the Pentacam Scheimpflug system with the CCT measured using ultrasound pachymetry (UP) and to compare the compatibility between the methods in normal, keratoconic, and cross-linked keratoconic corneas. METHODS: The study included 50 eyes of 50 patients with keratoconus (keratoconus group), 50 eyes of 50 patients with progressive keratoconus who underwent corneal cross-linking treatment (CCL group), and 50 eyes of 50 healthy subjects (control group). Patients in the keratoconus and CCL groups were further classified into mild (mean keratometry [Km] ≤ 47 D) and moderate keratoconus subgroups (47.0 < Km < 52.0 D). CCT values were noted from the Pentacam Scheimpflug and UP. RESULTS: The difference between the Pentacam and UP values was largest in the CCL group (-20.9 0.21.5 µm), followed by the keratoconus and control groups (-10.6 0.20.3 and 0.4 0.6.8 µm). The Pentacam and UP measurements were not comparable in the keratoconus and CCL groups (P = 0.001 and P < 0.001), whereas they were comparable in the control group (P = 0.62). In subgroup analysis, the 2 methods were comparable in the mild keratoconus subgroup (P = 0.12) and not comparable in the moderate keratoconus subgroup and in both mild and moderate subgroups of the CCL group (P = 0.001, P < 0.001 and P < 0.001). CONCLUSIONS: Pentacam Scheimpflug tomography and UP can be used interchangeably in normal and mild keratoconic eyes, but not in moderate keratoconic and cross-linked keratoconic eyes. Pachymetry measurements from Scheimpflug must be interpreted with extreme caution with different methods before planning an invasive procedure in these eyes.

Topometric and Tomographic Evaluation of Subclinical Keratoconus.

PURPOSE: To investigate the corneal topometric and tomographic findings that can be used in the diagnosis of subclinical keratoconus. METHODS: A retrospective cohort study. The study group was selected from patients with clinically evident keratoconus in one eye and subclinical keratoconus without evident topographic findings in fellow eye. The age-matched control group was selected from patients who were candidates for laser in situ keratomileusis (LASIK) and did not develop ectasia after LASIK surgery at least 1-year follow-up. All subjects underwent topographic, topometric and tomographic (Belin-Ambrósio Enhanced Ectasia Display III) analyses via a Pentacam HR rotating Scheimpflug camera (Oculus, Germany, version 1.20r.98) before LASIK surgery. RESULTS: The study group consisted of 151 patients (69 male and 82 female, mean age of 24.8 ± 7.2 years) and the control group also consisted of 150 patients (70 male and 80 female, mean age of 26.0 ± 6.3 years). There were statistically significant differences in all measured topometric (p˂.05) and tomographic (p˂.001) parameters between the eyes with subclinical keratoconus and those of the control group. In discriminating eyes with subclinical keratoconus from normal eyes, final D showed the highest area under curve value (0.858, sensitivity 85.2%, specificity 66.7%), followed by maximum pachymetric progression index (0.809, sensitivity 81.9%, specificity 69.4%) and average pachymetric progression index (0.796, sensitivity 81.9%, specificity 68.1%) in receiver operating characteristic analysis. CONCLUSION: Topometric and tomographic parameters might be useful for early detection of keratoconus, but the sensitivity and specificity of any parameter are not high enough to be used alone.

Association between disorganization of the retinal inner layers and capillary nonperfusion area in patients with retinal vein occlusion.

PURPOSE: To determine the correlation between the extent of disorganization of the retinal inner layers (a parameter of spectral domain optical coherence tomography) and optical coherence tomography angiography parameters in eyes with center-involved macular edema associated with retinal vein occlusion. METHODS: This retrospective observational study included 34 eyes of 34 patients with newly diagnosed macular edema associated with retinal vein occlusion and evidence of center-involved macular edema. Optical coherence tomography angiography and spectral domain optical coherence tomography were evaluated after resolution of the macular edema. Disorganization of the retinal inner layers was determined via spectral domain optical coherence tomography and optical coherence tomography angiography parameters, including foveal avascular zone area in the superficial capillary plexus and capillary nonperfusion areas, foveal avascular zone area in full retinal vasculature, foveal avascular zone perimeter, acircularity index of the foveal avascular zone, and foveal density. RESULTS: The mean disorganization of the retinal inner layers extent was 512.72 ± 238.47 microns, and the mean capillary nonperfusion area was 4.98 ± 2.85 mm2. There was a positive correlation between the extent of disorganization of the retinal inner layers and capillary nonperfusion area (p<0.001, r=0.901). Greater extent of disorganization of the retinal inner layers and the capillary nonperfusion area was correlated with wider foveal avascular zone area (p=0.014 and p=0.036, respectively) in the superficial capillary plexus and decreased foveal density (vessel density in 300 microns around the foveal avascular zone) (p=0.031 and p=0.022, respectively). These parameters were also correlated with decreased vessel density in both the superficial capillary plexus and deep capillary plexus in the parafoveal and peri-foveal regions (p<0.05 for all). CONCLUSIONS: Disorganization of the retinal inner layers appears to be a correlated biomarker of capillary ischemia in retinal vein occlusion. The extent of disorganization of the retinal inner layers was strongly correlated with the capillary nonperfusion area. This may support the notion that the extent of disorganization of the retinal inner layers can be used as an easily obtainable and crucial surrogate marker of capillary ischemia.

Effects of Topical Nepafenac and Fluorometholone on Macular Thickness After Posterior Capsulotomy Using Neodymium-doped Yttrium-Aluminum-Garnet Laser.

OBJECTIVES: The aim of this study was to assess the effects of topical 0.1% nepafenac and 0.1% fluorometholone on macular thickness (MT) after a neodymium: yttrium-aluminum-garnet (Nd: YAG) laser posterior capsulotomy and to compare the findings with those of untreated patients. METHODS: This prospective study included 75 eyes of 75 patients with posterior capsule opacification. The patients were divided into 3 groups according to the medications administered after a capsulotomy procedure. Group 1 comprised 25 patients who were prescribed 0.1% nepafenac for a week, Group 2 consisted of 25 patients who were prescribed 0.1% fluorometholone for a week, and Group 3 consisted of 25 patients who were not prescribed any medication. A circular-shaped capsulotomy was performed in all cases. MT was measured before the capsulotomy and at the first day, first week, and first month after the procedure using spectral domain-optical coherence tomography and the change values were compared within and between groups. RESULTS: In Group 1, the superior and nasal parafoveal MT, temporal, and nasal perifoveal MT values at the first month were statistically significantly greater than those observed in the first week (p<0.05 for all values). In Group 2, the superior and nasal parafoveal MT and inferior perifoveal MT measurements in the first month were greater than those recorded the first week (p<0.05 for all values). In Group 3, there was a gradual increase seen in the first day, first week, and first month in the superior and temporal parafoveal MT value (p<0.05 for all). The change value in the parafoveal temporal quadrant was significant between groups, indicating a greater increase in the untreated group compared with the nepafenac and fluorometholone groups (p=0.04). CONCLUSION: An increase in MT can occur after an Nd: YAG laser posterior capsulotomy. Both topical 0.1% nepafenac and 0.1% fluorometholone can prevent this increase. The 2 drugs were comparable; neither demonstrated apparent superiority to the other.

Effect of microalbuminuria on macular thickness in patients with type-2 diabetes mellitus.

PURPOSE: To investigate the effect of microalbuminuria on macular thickness in patients with type-2 diabetes mellitus with no or mild diabetic retinopathy and to investigate the relationship between macular thickness and metabolic parameters. MATERIALS AND METHODS: Fifty eight eyes of 58 patients without diabetic retinopathy (group 1) in microalbuminuria stage, 42 eyes of 42 patients with mild diabetic retinopathy (group 2) in microalbuminuria stage, and 50 eyes of 50 patients without diabetic retinopathy and microalbuminuria (group 3) were included in this study. After detailed ophthalmologic examination, all patients underwent spectral domain-optical coherence tomography measurements. Macular thickness was noted from nine different areas (fovea, four parafoveal, and four perifoveal areas) and compared between groups. The correlations between macular thickness and age, duration of diabetes mellitus, microalbuminuria, serum urea, creatinine, glycosylated hemoglobin (HbAIc), albumin, sodium (Na), and urinary Na were evaluated. RESULTS: The mean age was 53.29 ± 6.49 in group 1, 55.86 ± 6.97 in group 2, and 52.98 ± 5.66 years in group 3 (p = 0.06). The macular thickness values of superior, inferior, and nasal parafoveal areas were significantly different between groups (p = 0.001, p = 0.006, and p = 0.03, respectively). Bonferroni post test revealed that this difference originated from the difference between group 2 and 3 (p < 0.05 for all values). There were significant negative correlations between the macular thickness values of parafoveal areas and serum urea, HbA1c, albumin, microalbuminuria levels (p < 0.05 for all values). CONCLUSION: In this study, a significantly decreased parafoveal macular thickness was measured in patients with mild diabetic retinopathy and microalbuminuria compared to patients without diabetic retinopathy and microalbuminuria.

Tear function and ocular surface changes following corneal collagen cross-linking treatment in keratoconus patients: 18-month results.

PURPOSE: To investigate the long-term effects that CXL has on the tear function and ocular surface in keratoconus. METHODS: Twenty-one consecutive patients (24 eyes) with progressive keratoconus scheduled for CXL were included. All patients underwent the following procedures: conjunctival impression cytology analysis, ocular surface disease index (OSDI) score, tear osmolarity test, Schirmer test, tear film breakup time (TBUT), ophthalmic surface fluorescein (Fl) staining, and topographical corneal evaluation before as well as 3 and 18 months after accelerated CXL. RESULTS: There was no change in the median OSDI score, tear osmolarity test, Schirmer test, and the Fl staining score after CXL. The median TBUT increased from 9.00 s at baseline to 12.00 s at 18 months postoperative (P < 0.001). The cytological features of the temporal and superior bulbar conjunctiva deteriorated at 3 months post-CXL (P < 0.001). An improvement in impression cytology analysis of the temporal conjunctiva was noted at 18-month follow-up (P < 0.001). Significant improvements in the median maximum keratometry and mean keratometry (K-mean) readings were also noted 18 months after CXL (P < 0.001). The changes in the K-mean correlated significantly with the changes in TBUT levels at 18-month follow-up as compared to baseline (r = - 0.688, P < 0.001). CONCLUSIONS: The improvement in TBUT, conjunctival squamous metaplasia, and the goblet cell density indicates a favorable effect of CXL on the ocular surface and tear film in keratoconus, presumably due to the reduced corneal irregularity after CXL.

Corneal Endothelial Morphology and Thickness Changes in Patients with Gout

Objectives: To investigate corneal endothelial cell density (ECD), morphology, and central corneal thickness (CCT) in patients with gout compared with healthy subjects. Materials and Methods: Fifty eyes of 50 gout patients and 50 eyes of 50 healthy subjects without gout or any other systemic disease were included in this study. After detailed ophthalmologic examination, specular microscopy (Tomey EM-4000; Tomey Corp) measurement was performed for all participants. ECD, average cell area (ACA), coefficient of variation (CV), hexagonality ratio, and CCT values were recorded. Results: Mean ECD and hexagonality ratio were lower (p=0.004 and p=0.002) and CV, ACA, and CCT values were higher (p=0.001, p=0.007, and p=0.001) in patients with gout when compared to healthy subjects. There were significant correlations between gout disease duration and CD and hexagonality ratio (p=0.019 and p=0.043) and also between uric acid value and hexagonality ratio and CCT (p=0.044 and p=0.003). Conclusion: Altered corneal endothelial function was found in patients with gout when compared to healthy subjects and the alteration increased as gout duration and uric acid value increased.

Biomechanical Analysis of Subclinical Keratoconus With Normal Topographic, Topometric, and Tomographic Findings.

PURPOSE: To investigate the corneal biomechanical responses of subclinical keratoconus with normal topographic, topometric, and tomographic findings. METHODS: In this prospective observational study, the study group was selected from patients with clinically evident keratoconus in one eye and subclinical keratoconus with normal topographic, topometric, and tomographic findings in the fellow eye. The control group was selected from candidates for contact lens use. The biomechanical analyses were performed using the Corvis ST (Oculus Optikgeräte, Wetzlar, Germany). The following parameters were analyzed: A1 velocity, A2 velocity, A1 length, A2 length, deformation amplitude ratio, stiffness parameter at the first applanation, Corvis Biomechanical Index, and Tomographic and Biomechanical Index (TBI). RESULTS: The study group consisted of 21 patients (10 men and 11 women; mean age: 27.7 ± 6.9 years), and the control group consisted of 35 patients (17 men and 18 women; mean age: 26.1 ± 5.8 years). No significant differences were found between the eyes with subclinical keratoconus and normal eyes in corrected distance visual acuity and the topographic, topometric, and tomographic parameters (P > .05). Significant differences were found in the values of A2 length, A1 velocity, A2 velocity, and TBI between the subclinical keratoconus group and the control group (P < .05). In distinguishing eyes with subclinical keratoconus from normal eyes, the TBI showed the highest area under the curve (0.790; cut-off: 0.29; sensitivity: 67%; specificity: 86%) in the receiver operating characteristic analysis. CONCLUSIONS: Biomechanical analysis with the Corvis ST may be used as a complementary diagnostic method in detecting subclinical keratoconus. [J Refract Surg. 2019;35(4):247-252.].

Longitudinal Evaluation of the Progression of Keratoconus Using a Novel Progression Display.

OBJECTIVES: To evaluate the longitudinal tomographic changes and to compare the discriminatory potential of a novel progression display between progressive and nonprogressive keratoconic eyes. METHODS: Retrospective evaluation was made of 81 eyes of 81 patients with keratoconus who had undergone Scheimpflug measurements at least twice with an interval of 12 months or longer between each measurement. The progressive group was defined as 36 eyes, which showed progression according to the definition of the global consensus on keratoconus and ectatic diseases when 2 of the 3 criteria were met, and the other 45 eyes were considered the nonprogressive group. The main outcome measures from progression display were "A" for anterior radius of curvature, "B" for posterior radius of curvature, "C" for thinnest pachymetry, "D" for distance visual acuity; Kmax; Q-value front and back; index of surface variance (ISV), vertical asymmetry, height asymmetry, and height decentration; overall deviation of normality (final D); average pachymetric progression index; and maximum Ambrósio relational thickness. RESULTS: The rate of change per year of A, B, C, thinnest pachymetry, Kmax, final D, and ISV was significantly different between groups (P≤0.01 for all values). It was determined that yearly change rates greater than 0.12 for A, 0.14 for B, 10.04 µm for thinnest pachymetry, 0.68 D for Kmax, 0.15 for final D, and 2.11 for ISV might indicate progression in keratoconus management. CONCLUSIONS: Belin progression display parameters may be useful in discriminating progressive from nonprogressive keratoconic eyes.

Corneal crosslinking in a case with Axenfeld-Rieger syndrome and unilateral pellucid marginal degeneration.

A 31-year-old male patient presented with the complaint of progressive vision loss in his left eye. Slit-lamp examination showed posterior embryotoxon, iris hypoplasia, and iridocorneal adhesion in both eyes, corectopia in the right, and peripheral inferior thinning and ectasia in the left eye. Corneal topography showed slightly asymmetric bowtie pattern in the right eye and crab-claw pattern in the left eye. Topographic examination was compared with his previous topography. The comparison showed 1.6-D steepening of maximum keratometry (Kmax ) and 22-µm decrease of thinnest corneal pachymetry. Corneal crosslinking treatment was performed on the left eye. At the postoperative 28-month follow-up visit, Kmax decreased from 54.1 to 53.0 D and corrected distance visual acuity improved to 20/20 with scleral lens. This is the first reported a case with Axenfeld-Rieger syndrome and pellucid marginal degeneration association. We suggest that corneal crosslinking can be useful for management of pellucid marginal degeneration and longer follow-up might be needed in order to corroborate the effectiveness of the corneal crosslinking procedure.