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Purpose: To investigate the correlation between outer and inner retina optical coherence tomography (OCT) biomarkers and visual acuity in patients with idiopathic epiretinal membrane (iERM) and identify which of them may be predictive of visual function., Methods: A retrospective cross-sectional single-center study was conducted that included patients diagnosed with iERM. Spectral domain OCT images were obtained and assessed qualitatively and quantitatively. The association of OCT parameters with best corrected visual acuity was analyzed., Results: Charts of 97 eyes of 97 patients were reviewed. Central foveal thickness, maximal retinal thickness (MRT), photoreceptor outer segment length, outer foveal thickness, ganglion cell-inner plexiform layer complex thickening, inner retinal thickness and inner retinal layer irregularity index were among the major outcome measures. OCT scans were also assessed for the presence of cotton ball sign, ellipsoid zone disruption, ectopic inner foveal layer, disorganization of retinal inner layers (DRIL), intraretinal fluid, subretinal fluid (SRF) and epimacular membrane rip. Univariate analysis showed statistically significant association between all the aforementioned parameters with worse vision, except for cotton ball sign and SRF. Multivariate analysis found that MRT and severe DRIL were strongly correlated with worse vision ( p  < 0.001)., Conclusion: MRT and severe DRIL should be considered as negative prognostic factors for visual acuity.

Purpose: To evaluate the outcomes of a new antiglaucoma surgical method, a modification of the standard deep sclerectomy, the penetrating deep sclerectomy., Participants: Patients with medically uncontrolled primary open-angle glaucoma or pseudoexfoliative glaucoma were prospectively, in a consecutive way, enrolled in this study., Methods: The study was conducted in Glaucoma Unit, Department of Ophthalmology, University of Hospital of Alexandroupolis, Greece, in 29 eyes of 29 patients. In a fornix-based surgical procedure, all eyes underwent the proposed penetrating deep sclerectomy (deep sclerectomy plus trabeculectomy) with the use of mitomycin C applied intraoperatively (0.2 mg/mL for 2 min). The follow-up period was 3 years. Ocular examination was conducted before the operation and at 1, 3, 6, 12, 18, 24, and 36 months postoperatively., Results: The average reduction in intraocular pressure at the end of follow-up was 11.24 (57.88%). The complete success rate (intraocular pressure ⩽21 mm Hg without medication) after 3 years was 58.6%. The qualified success rate (intraocular pressure ⩽21 mm Hg without or with medication) was 75.86%. Postoperatively, the mean number of medication dropped from 3.75 ± 0.89 to 0.89 ± 0.98. Low postoperative complications were recorded., Conclusion: During the 3-year follow-up period, penetrating deep sclerectomy presented very positive outcome. The addition of a controlled perforation of the trabeculo-Descemet's membrane in deep sclerectomy, playing the role of an early goniopuncture, seems to ensure a satisfactory outcome and is not associated with additional complications.

Purpose: To evaluate the reproducibility of different Scheimpflug imaging-derived reference bodies in normal, keratoconus (KC), and crosslinked (CXL) eyes., Methods: In this prospective, observational study, 40 participants populated the control group (CG), while 33 and 34 patients formed the KC group and the CXL group, respectively. One eye was randomly selected when both were eligible. Elevation measurements were obtained using Scheimpflug camera, by applying the following reference bodies: the best fit sphere (BFS), the best fit toric ellipsoid (BFTE), the best fit toric ellipsoid with fixed eccentricity of 0.4 (BFTEF), the best fit ellipsoid (BFE), and the best fit torus, by 2 operators in 2 sessions. The variability of different reference bodies' parameters was assessed using intraclass correlation coefficient (ICC)., Results: Differences between operators were nonsignificant for all reference bodies' parameters in all study groups (p&gt;0.1). Regarding CG, BFS for both operators and BFTE for operator 1 presented the best intrasession repeatability (majority of ICCs &gt;0.90), while average interobserver reliability was recorded for the majority of reference bodies' parameters. Regarding KC and CXL groups, BFS, BFTEF, and BFE reference bodies demonstrated the best intrasession and interobserver reproducibility (majority of ICCs &gt;0.90) for both groups. Steep and flat radius parameters presented the best overall reproducibility, with the majority of ICCs for all reference bodies ranging above 0.90, in all study groups., Conclusions: High variability was encountered for most reference surfaces. Ellipsotoric surfaces presented acceptable repeatability in KC and post-CXL corneas.

Purpose: To evaluate the sensitivity and specificity of corneal biomechanical metrics, anterior segment data, and a combination model in differentiating forme fruste keratoconus (FFK) from normal corneas., Methods: A total of 50 FFK eyes were identified by calculation of the KISA index and recruited FFK group. Results were compared with 50 normal eyes (NG group) randomly selected from 50 patients. The following parameters were evaluated for their diagnostic capacity by evaluation of their receiver operating characteristic curves (ROC): corneal hysteresis (CH), corneal resistance factor (CRF), corneal astigmatism (Cyl), anterior chamber depth (ACD), corneal volume (CV) at 3 mm (CV3) and at 5 mm (CV5), maximum posterior elevation value (PEL), central corneal thickness (CCT), thinnest corneal thickness (TCT) and its coordinates (TCTx, TCTy ), the ratio TCT/CCT, pachymetric progression indexes (PPImin, PPIavg, and PPImax), and Ambrósio's relational thickness (ARTmin, ARTavg, and ARTmax). Logistic regression was attempted for identification of a combined diagnostic model., Results: Significant differences were detected in all studied parameters except the Cyl, ACD, TCTx, and CV. Among individual parameters, the highest predictive accuracy was for ARTavg (area under the curve [AUC] 95.4%, sensitivity 90%, specificity 88.9%) and TCT (AUC 95.3%, sensitivity 90.9%, specificity 89%). Sufficient predictive accuracy (AUC 99.4%, sensitivity 98.8%, specificity 94.6%) was identified in a diagnostic model that combined the CRF, ARTavg, and PEL parameters., Conclusions: None of the individual parameters provide sufficient diagnostic capacity in FFK. However, diagnostic models that combine biomechanical and tomographic data seem to provide high accuracy in differentiating FFK from normal corneas.

Purpose: To perform qualitative evaluation of the aqueous humor (AH) outflow mechanism in glaucoma and nonglaucoma patients by means of tonography assessment and mathematical analysis., Methods: Sixty-two primary open angle and 58 pseudoexfoliation glaucoma patients were recruited in a non-interventional, observational study between 2004 and 2007. Qualitative and quantitative outflow assessment was acquired by means of a digital tonographer and mathematical analysis. Qualitative results were represented using slope analysis of the change of the AH outflow rate over the tonography study. The results were compared to the control group (CG; n=100) as well as to a pseudoexfoliation group (PEX; n=46)., Results: Regarding quantitative analysis, glaucoma groups exhibited significantly lower outflow facility compared to nonglaucoma ones (p<0.001). Outflow facility value was significantly correlated to cup to disc ratio (Pearson correlation r=-0.3, p<0.001). Regarding qualitative analysis, the primary open-angle glaucoma (POAG) group presented a significant profile variation at the beginning of the tonography, expressed as an increased resistance of the AH outflow. Both glaucoma groups exhibited profile stabilization at the end of the measurement, suggesting that the outflow rate remained constant, while nonglaucoma groups followed a continuous reduction of the AH outflow rate throughout the study., Conclusions: The POAG, PXG, PEX, and CG groups demonstrated both qualitative and quantitative tonographic profile differences. The observed differences in the glaucoma groups suggest a distinct pathomechanism between POAG and PXG. It is suggested that POAG patients have a temporary disruption of the AH flow pathway, while PXG patients have a generalized increased flow resistance.

Purpose: To evaluate the psychometric properties of the Greek National Eye Institute Refractive Error Quality of Life Questionnaire (NEI-RQL-42)., Methods: We developed the Greek version of the instrument using forward and backward translation. To examine reliability, Cronbach alpha for each subscale was used as an index of internal consistency. Test-retest reliability was evaluated with intraclass correlation coefficients (ICC). Regarding construct validity, both convergent and discriminant validities were calculated by means of multi-trait analysis. Furthermore, the instrument was evaluated by Rasch analysis, as well., Results: Three patient groups were studied (emmetropes (n = 20), myopes (n = 41), and hyperopes (n = 18)). Emmetropes scored significantly better in the majority of subscales, while myopes scored better than hyperopes in clarity of vision (p = 0.012), near vision (p<0.001), and satisfaction with correction (p = 0.001). Cronbach alpha ranged from 0.490 (glare) to 0.948 (expectations), with most subscales having high internal consistency. The ICCs ranged from 0.76 to 0.93 for all subscales. All items passed the convergent and discriminant validity tests. Strong correlations were detected between uncorrected visual acuity and near vision, expectations, activity limitations, dependence on correction, worry, and suboptimal correction subscales. Rasch analysis revealed potential weaknesses of the instrument that are associated with the assumptions of the model itself. Specifically, 3 items and 17.5% of the participants fell outside the tolerance box. Moreover, principal component analysis indicated average unidimensionality for the instrument., Conclusions: Traditional validation methods indicate that the Greek NEI-RQL-42 scale has adequate psychometric properties for comparative studies in local populations. Rasch analysis indicates significant misfits to the model that should be taken into consideration and evaluated in future studies. These misfits might reflect inherent weaknesses of the original NEI-RQL-42 and not of its adaptation to Greek norms.

Purpose: To evaluate the Goldmann applanation tonometer (GAT), the Pascal dynamic contour tonometer (PDCT), and the ocular response analyzer (ORA) tonometer in measuring intraocular pressure (IOP) in keratoconic eyes before and after riboflavin/ultraviolet A corneal collagen crosslinking (CXL), to assess agreement among devices and to analyze the impact of some ocular parameters on their measurements., Methods: Fifty keratoconic eyes were included. Intraocular pressure was measured with GAT, PDCT, and ORA before and after CXL. Fifty nonkeratoconic eyes served as controls. Device agreements were calculated by Bland-Altman analysis. The effect of some ocular characteristics on IOP measurement differences between tonometers was determined., Results: Between the 2 groups, there were statistically significant differences in all examined parameters. Preoperatively, in both groups a statistically significant difference was found in IOP measurements among devices (p<0.05). Bland-Altman analysis showed a bias among devices. On average, PDCT overread GAT and ORA. The IOP measurement differences were better predicted by corneal resistance factor. Postoperatively, in keratoconus eyes, there was no statistically significant difference in IOP measurements among the 3 tonometers (p>0.05). The IOP readings with all tonometers after treatment were higher than those obtained preoperatively; however, not to a statistically significant level, with the exception of PDCT and ORA readings at the first month postoperatively. Corneal resistance factor measurements have no significant change after CXL., Conclusions: Pascal dynamic contour tonometer could provide more consistent and closer to the true IOP readings than GAT and ORA in healthy eyes with corneal thickness outside the 520-550 µm range, in keratoconus patients and after CXL. Corneal resistance factor was associated significantly with agreement among devices.

Purpose: To develop a reliable and practical questionnaire for glaucoma awareness and evaluate the impact of potential determinants., Methods: Patients with primary open-angle, pigmentary, and exfoliation glaucoma, as well as healthy controls, were recruited. The instrument included questions about demographic characteristics, as well as 8 questions assessing the participant's familiarity with glaucoma. Rasch analysis was used for the validation of the questionnaire. The effect of demographics as potential determinants of awareness was examined with a multivariate logistic regression analysis. Bonferroni-corrected statistical significance was tested with the Mann-Whitney U test or one-way analysis of variance. Association between demographics and questionnaire scores was examined with Spearman correlation., Results: As indicated by power analysis, responses from 175 patients (mean age 65.5 years) and 314 controls (mean age 43.3 years) were analyzed. Rasch analysis indicated no multidimensionality and good item-person targeting. Mean ± SD awareness scores for the glaucoma and control groups were 4.43 ± 2.10 and 4.20 ± 2.11, respectively (p=0.207). Sex and residence were not predictors of disease awareness, whereas educational level was only a determinant in the control group (p<0.001). Income was a predictor only for patients (r=0.357, p<0.001), whereas family history was predictive for both groups (p<0.001). Logistic regression analysis revealed that only family history was associated with increased awareness (Chi(2)=4.61, p=0.03, odds ratio 1.98)., Conclusions: This study introduces a practical and valid instrument for the assessment of glaucoma awareness.

Purpose: To present a case of ocular decompression retinopathy occurring after an uncomplicated nonpenetrating glaucoma procedure (deep sclerectomy with mitomycin C)., Methods: A 52-year-old man with medically uncontrolled exfoliation glaucoma in the left eye underwent uneventful deep sclerectomy with mitomycin C. The patient had no history or laboratory evidence of any bleeding disorder., Results: On the first postoperative day, visual acuity fell from the preoperative level of Snellen 0.2 to hand movement and the intraocular pressure was 5 mmHg. Funduscopy revealed a small intravitreal hemorrhage and multiple, extended retinal hemorrhages in all quadrants of the fundus. After standard postoperative medication with antibiotic/steroid eyedrops, the patient's visual acuity returned to preoperative levels and the retinal hemorrhages were absorbed. Three and a half months postoperatively, the fundus was free of bleedings., Conclusions: Although decompression retinopathy has previously been described after penetrating glaucoma surgery, the condition can also occur after uncomplicated deep sclerectomy. Despite the dramatic presentation, the prognosis remains favorable.

Purpose: To determine the reproducibility of optical coherence tomography/scanning laser ophthalmoscope (OCT/SLO) measurements within and between observers and within and between sessions in healthy eyes., Methods: Forty eyes of 40 healthy volunteers recruited from the outpatient service of the Department of Ophthalmology at the University Hospital of Alexandroupolis, Greece, were included. Retinal thickness scans were performed 3 times by two experienced operators within each of 3 sessions, which took place within a month, using the spectral OCT/SLO. The OCT/SLO provides retinal nerve fiber layer (RNFL) thickness and volume measurements and a 3D tomography analysis of optic nerve head. Statistical analysis was conducted using Bland-Altman plots, coefficient of variation (CoV), and intraclass correlation coefficient (ICC)., Results: As shown by the CoV values, RNFL parameters were generally found to have high reproducibility (CoV ranging from 4.3% to 10.9% for both operators), whereas optic disc parameters had scores reaching up to 22.5%. On the other hand, as shown by the ICC values, intraobserver and interobserver reproducibility for the OCT/SLO was high for optic disc parameters but low for RNFL thickness and volume measurements. Interobserver reproducibility was found to be highest for the maximum cup depth parameter and lowest for the superior volume. Bland-Altman plots indicate that bias is minimal for practically all parameters and scatterplot homoscedasticity is high., Conclusions: According to our data, SLO/OCT generally has a good reproducibility profile, as differences between the two operators were small. However, additional studies on the reproducibility of measurements with the OCT/SLO are needed.

Purpose: to evaluate the retinal nerve fiber layer(RNFL) profile of healthy controls, persons with exfoliation syndrome (XFS), and patients with exfoliation glaucoma (XFG) and primary open angle glaucoma(POAG)., Methods: One eye from each of 269 participants was analyzed. Fifty eyes were normal , 45 eyes had XFS, 89 eyes had POAG, and 89 had XFG. Glaucoma patients were divided according to the severity of the disease into mild and advanced groups. All participants underwent imaging with the GDx-VCC device. Measurements of the parameters TSNIT average, TSNIT SD, and nerve fiber indicator (NFI) were performed. Polametric RNFL thickness values were compared by means of Bonferroni-corrected t-tests., Results: Regarding control and glaucoma groups, statistically significant differences were identified in all GDx parameters. RNFL thickness values of the control group differed significantly from the values of the XFS group. There was no statistically significant difference between RNFL thickness values for the mild POAG and mild XFG groups or for the advanced POAG and advanced XFG groups., Conclusions: Polarimetry-determined RNFL in eyes with XFS is thinner than that of healthy eyes. No differences in RNFL thickness were found when eyes with POAG and XFG of similar severity were compared.