Risk factors for ocular hypotony after XEN Gel Stent implantation.

PURPOSE: To investigate the incidence of postoperative hypotony, and risk factors for the development of hypotony in eyes who had undergone XEN Gel Stent implantation. METHODS: In this retrospective, single-centre case series, medical records of 170 consecutive eyes who had undergone XEN Gel Stent implantation with or without simultaneous phacoemulsification for primary or secondary open angle glaucoma were analysed. Primary outcome parameters were the incidence of postoperative hypotony and potential risk factors for its development, and secondary parameters were pre- and postoperative visual acuity, intraocular pressure (IOP), and number of IOP-lowering eye drops. RESULTS: Postoperative hypotony ≤ 6 mmHg occurred in 57% of eyes. Hypotony was without complications in 70.1%, 13.4% had transient complications with spontaneous resolution, and 16.5% had complications requiring treatment. Mean visual acuity logMAR before surgery accounted for 0.47 ± 0.46 in all eyes and 0.47 ± 0.48 at the 4-week visit. There was no significant difference of BCVA in the group of eyes with and without postoperative hypotony before and after surgery. The mean IOP before surgery was 24.6 ± 8.4 mmHg and decreased significantly to 18.4 ± 10.2 after 4 weeks. Eyes with an axial length over 24.3 mm had a threefold increased risk for postoperative hypotony (OR 3.226, 95% confidence interval 1.121-9.279). This risk was decreased in eyes with simultaneous cataract surgery (OR 0.483, 95% confidence interval 0.258-0.903). CONCLUSION: In our sample, postoperative hypotony was a common complication after XEN Gel Stent implantation, but serious, persistent complications were rare. A longer axial length predisposes the eye for the development of hypotony.

Serum Selenium Levels in Glaucoma: a Pilot Study.

BACKGROUND: Trace elements are assumed to be involved in glaucoma pathogenesis via changes in oxidative stress. Especially serum selenium (Se) has been linked to this neurodegenerative disease. Serum Se levels differ between countries due to nutrition and ethnicity. It was the aim of the present study to investigate serum Se levels in primary open-angle glaucoma (POAG) patients and controls in Germany and to consider potential age and gender effects. MATERIAL AND METHODS: The Se concentration of 39 serum samples (22 patients with POAG, 17 controls) were analyzed by inductively coupled plasma-sector field mass spectrometry (ICP-sf-MS) in high resolution mode. Covariance and percentile regression were analyzed. Age and gender were defined as confounding factors and their different trends were investigated. Moreover, age was examined across different quantiles of Se levels. RESULTS: Total serum least-squares means (LS-means) Se levels were 132.02 µg/L (controls) and 134.86 µg/L (POAG). Total serum Se levels did not differ between the study groups (p > 0.05). Significant age and gender effects of serum Se were observed. Quantile analysis showed that the 1st serum Se quantile decreased with increasing age in POAG patients in contrast to controls. The odds ratios of the 1st serum Se were 1.3 (with 2nd quantile) and 1.3 (with 3rd quantile), respectively. CONCLUSION: The serum Se level of the German cohort was almost half of those of the published US cohort (glaucoma 209.11 ng/mL; control 194.45 ng/mL). Age and gender effects were observed; the serum Se level increased with age in women (controls and POAG), however, Se levels decreased with age in men (controls and POAG).

Five-Year Long-Term Follow-Up of Selective Laser Trabeculoplasty in Open-Angle Glaucoma.

PURPOSE: Selective laser trabeculoplasty (SLT) is known as a safe laser therapy for an effective reduction in intraocular pressure (IOP). The aim of this study was to examine the therapeutic success of SLT in open-angle glaucoma (OAG) patients with a long-term follow-up of 5 years. METHODS: Forty-six eyes of forty OAG patients, some with previous intraocular surgery, underwent SLT (24 males, 16 females). Therapeutic success was categorized as: category (I) - IOP reduction ≤ 21 mmHg and > 20% compared to baseline IOP with additional glaucoma medication; category (II) - IOP reduction ≤ 18 mmHg and > 30% compared to baseline IOP with additional glaucoma medication; category (III) - IOP reduction ≤ 18 mmHg without any additional glaucoma medication at all follow-ups. Therapeutic failure was defined as the necessity of any further glaucoma surgery (IV). RESULTS: (1) SLT was well tolerated in all eyes, and no severe side effects or complications were recorded. (2) After 1-year follow-up, therapeutic success was 27% (I), 30% (II), and 3% (III). The therapeutic failure rate was 40% (IV). (3) After 2 years follow-up, therapeutic success was 7% (I), 10% (II), and 0% (III). The therapeutic failure rate was 83% (IV). (4) After 3 years follow-up, the therapeutic failure rate increased up to 100% (IV). CONCLUSION: SLT seemed to be effective in lowering IOP in the first year in the present cohort, however, the long-term effect is low and additional local therapy or surgical interventions are necessary.

Two-Year Follow-Up: Therapeutic Success with Respect to Axial Length of Stand-Alone Xen45 Gel Stent Implantation and Combined Procedures.

BACKGROUND: Up to now, no data have been available on the therapeutic success rate of Xen45 gel stent with respect to axial length (AL). The present study aimed to investigate a potential influence of AL on therapeutic success in stand-alone Xen45 gel stent implantation or combination with cataract surgery in open-angle glaucoma patients (OAG) with a follow-up of 2 years. MATERIALS AND METHODS: In this retrospective observational study, 98 eyes of 87 glaucoma patients of the Department of Ophthalmology, University of Erlangen Nürnberg, and from the Erlangen Glaucoma Registry (NCT00494923; ISSN 2191-5008, CS-2011) underwent stand-alone Xen45 gel stent implantation or a combination with cataract surgery. Therapeutic success was defined as ≥ 20% IOP reduction with the same or fewer anti-glaucomatous eye drops needed compared to baseline, yet without additional glaucoma-related surgery (expect bleb needling). Therapeutic failure was classified as any additional glaucoma-related surgery, IOP reduction < 20% or if more local anti-glaucomatous eye drops were applied compared to baseline. RESULTS: The therapeutic success rate was 60.7% (1 year) and 62.5% (2 years). No statistical difference was observed when procedures were combined with cataract surgery (p > 0.05). Subgroup analysis yielded no significantly different therapeutic success when considering glaucoma subtype [1 year: 61.5% (POAG), 60% (SAOG), 2 years: 54.5% (POAG), 69.2% (SOAG); p > 0.05]. Anti-glaucomatous medication use was lowered from 2.72 ± 1.04 at baseline to 0.61 ± 0.99 (1 year) and 0.7 ± 1.04 (2 years). The therapeutic success rate was seen to be independent of axial length for group and subgroup analysis (p > 0.05). Emmetropic eyes (22.0 - 24.5 mm) showed a statistically higher needling rate than myopic eyes (> 24.5 mm, p = 0.02). CONCLUSION: Minimal invasive glaucoma surgery is one therapeutic option in OAG eyes, with good reduction in IOP even after 24 months (with additional bleb needling). Therapeutic success seemed to be independent of axial length in the present study.

Structural changes of macular inner retinal layers in early normal-tension and high-tension glaucoma by spectral-domain optical coherence tomography.

PURPOSE: Assessment of the diagnostic ability of segmented macular inner retinal layer thickness and peripapillary retinal nerve fiber layer (pRNFL) measured by spectral-domain optical coherence tomography (SD-OCT) in patients with normal-tension (NT) and high-tension (HT) perimetric and preperimetric glaucoma. METHODS: The 212 participants included 45 healthy subjects, 55 patients with ocular hypertension, 56 patients with preperimetric glaucoma, and 56 patients with perimetric glaucoma. The preperimetric and perimetric groups were further subdivided into NT and HT groups. Sectoral and global thickness of macular retinal nerve fiber layer (mRNFL), ganglion cell layer (mGCL), inner plexiform layer (mIPL), ganglion cell complex (mGCC), and pRNFL were measured using SD-OCT (Spectralis, Heidelberg Engineering, Germany). Diagnostic performance was ascertained by sectoral and global comparison of the sensitivities at specificity ≥ 95%. RESULTS: For all layers, the largest thickness decrease was reported in the HT perimetric group. In all groups, the sensitivities of mGCL showed a comparable diagnostic value to pRNFL in order to distinguish between healthy subjects and glaucoma patients. In the perimetric group, mGCL (85.7%) exhibited higher sensitivities than mRNFL (78.6%) and mGCC (78.6%). Both mRNFL and pRNFL demonstrated equal diagnostic performance in the HT perimetric group (88.5 and 96.2%), in the NT groups, mRNFL was inferior to all other layers. CONCLUSION: The sensitivities of mGCL and mRNFL were comparable to the sensitivities of pRNFL. In clinical application, mGCL and mRNFL, with a focus on the temporal and inferior sectors, may provide a convincing supplementation to pRNFL. CLINICAL TRIAL REGISTRATION: Erlangen Glaucoma Registry www.clinicaltrials.gov ID: NCT00494923.

Precision of Optic Nerve Head and Retinal Nerve Fiber Layer Parameter Measurements by Spectral-domain Optical Coherence Tomography.

PURPOSE: The aim of this study was to assess the repeatability and reproducibility (R&R) of Bruch membrane opening based on minimum rim width (BMO-MRW), minimum rim area (BMO-MRA) and peripapillary retinal nerve fiber layer thickness (RNFLT) with the Spectralis optical coherence tomography (Heidelberg Engineering) for normal and glaucoma subjects. Precise measurement of these parameters can support detection of structural glaucomatous damage and progression. METHODS: This cross-sectional study included 16 healthy controls and 16 patients with glaucoma. One eye was randomly selected and included in this study. Subjects underwent 1 baseline and 3 follow-up measurements, using 3 different Spectralis optical coherence tomography devices in randomized order, each operated by a single operator. Outcome measures were global and sectorial averages of BMO-MRW and BMO-MRA, and of peripapillary RNFLT obtained from 12/14/16-degree circle scans. Coefficients of variation (COV) were calculated and a mixed-effects analysis of variance was performed to compare R&R between devices. RESULTS: COVs of global and sectorial BMO-MRW measurement under repeatability conditions ranged from 0.51% to 1.7% (normal, 0.62% to 1.3%; glaucoma, 0.64% to 2.3%). Respective COVs under reproducibility conditions ranged from 0.89% to 1.9% (normal, 0.77% to 2.8%; glaucoma, 1.1% to 2.6%). COVs of global and sectorial RNFLT measurements under repeatability conditions ranged from 0.5% to 2.8%. Respective COVs under reproducibility conditions ranged from 1.6% to 3.5%. CONCLUSIONS: For R&R, the COVs of measured parameters were by trend higher for glaucoma eyes compared with normal controls. The BMO-MRW measurement system has an excellent precision taking into account that major and minor corrections of segmentation have to be done by the examiner before evaluation.

Predictive Factors for Visual Field Conversion: Comparison of Scanning Laser Polarimetry and Optical Coherence Tomography.

PURPOSE: The purpose of this study was to compare the ability of scanning laser polarimetry (SLP) and spectral-domain optical coherence tomography (SD-OCT) to predict future visual field conversion of subjects with ocular hypertension and early glaucoma. METHODS: All patients were recruited from the Erlangen glaucoma registry and examined using standard automated perimetry, 24-hour intraocular pressure profile, and optic disc photography. Peripapillary retinal nerve fiber layer thickness (RNFL) measurements were obtained by SLP (GDx-VCC) and SD-OCT (Spectralis OCT). Positive and negative predictive values (PPV, NPV) were calculated for morphologic parameters of SLP and SD-OCT. Kaplan-Meier survival curves were plotted and log-rank tests were performed to compare the survival distributions. Contingency tables and Venn-diagrams were calculated to compare the predictive ability. RESULTS: The study included 207 patients-75 with ocular hypertension, 85 with early glaucoma, and 47 controls. Median follow-up was 4.5 years. A total of 29 patients (14.0%) developed visual field conversion during follow-up. SLP temporal-inferior RNFL [0.667; 95% confidence interval (CI), 0.281-0.935] and SD-OCT temporal-inferior RNFL (0.571; 95% CI, 0.317-0.802) achieved the highest PPV; nerve fiber indicator (0.923; 95% CI, 0.876-0.957) and SD-OCT mean (0.898; 95% CI, 0.847-0.937) achieved the highest NPV of all investigated parameters. The Kaplan-Meier curves confirmed significantly higher survival for subjects within normal limits of measurements of both devices (P<0.001). Venn diagrams tested with McNemar test statistics showed no significant difference for PPV (P=0.219) or NPV (P=0.678). CONCLUSIONS: Both GDx-VCC and SD-OCT demonstrate comparable results in predicting future visual field conversion if taking typical scans for GDx-VCC. In addition, the likelihood ratios suggest that GDx-VCC's nerve fiber indicator<30 may be the most useful parameter to confirm future nonconversion. (http://www.ClinicalTrials.gov number, NTC00494923; Erlangen Glaucoma Registry).

Can Glaucomatous Visual Field Progression be Predicted by Structural and Functional Measures?

PURPOSE: The aim of this study was to compare the predictive value of retinal nerve fiber layer thickness (RNFLT) measurements obtained by optical coherence tomography (OCT), morphometric parameters of confocal scanning laser ophthalmoscopy (CSLO), and frequency-doubling technique perimetry to predict visual field conversion of normal individuals, ocular hypertensive subjects, and early preperimetric glaucoma patients as determined by standard automated perimetry (SAP). PATIENTS AND METHODS: This longitudinal single-center study included 107 eyes of 56 controls, 164 eyes of 98 patients with ocular hypertension, and 169 eyes of 110 patients with preperimetric glaucoma. At baseline, all patients and controls underwent OCT (Spectralis OCT), CSLO (Heidelberg Retina Tomograph) examination, optic disc photography, and frequency-doubling technique perimetry. At baseline SAP was normal in all participants. Univariate and multivariate hazard ratios (HRs) were measured to model the conversion-free survival including morphometric functional and clinical variables. RESULTS: The median follow-up period was 6.9 years. In total, 48 eyes (10.9%) demonstrated visual field conversion in the follow-up. RNFLT temporal-inferior outside normal limits demonstrated the highest HR with 1.2 (95% confidence interval, 1.1-1.4) per 10 µm loss for OCT, and Glaucoma probability score global outside normal limits demonstrated the highest HR with 1.3 (95 % confidence interval, 1.1-1.5) per 0.1 increase for CSLO in a multivariate model adjusted for photograph-based glaucoma staging, central corneal thickness, and SAP pattern SD. CONCLUSIONS: Both measurement of RNFLT by OCT and Glaucoma probability score by CSLO are highly predictive of future visual field conversion and provide independent predictive information beyond optic disc assessment, central corneal thickness, and SAP pattern SD.

Comparison of Bruch's Membrane Opening Minimum Rim Width and Peripapillary Retinal Nerve Fiber Layer Thickness in Early Glaucoma Assessment.

PURPOSE: To compare the diagnostic value of Bruch's membrane opening minimum rim width (BMO-MRW) and retinal nerve fiber layer thickness (RNFLT) in patients with ocular hypertension, preperimetric, and perimetric glaucoma. METHODS: One hundred eighty-one eyes consisting of 40 healthy controls, 41 ocular hypertensive subjects, 50 subjects with preperimetric glaucoma and 50 with perimetric glaucoma were included. One randomly selected eye was included. All patients underwent slit-lamp examination, funduscopy, achromatic perimetry, and 24-hour IOP profile. Bruch's membrane opening-MRW and RNFLT (3 peripapillary circle scans, 12°/14°/16°) data were obtained using spectral domain optical coherence tomography. Areas under the receiver operating characteristics curves (AUROC) as well as sensitivity at fixed specificity were computed globally and for six vertical split sectors. Venn diagrams were plotted to identify patients that were diagnosed by one of the two parameters only. RESULTS: For RNFLT the smallest circle diameter showed highest diagnostic accuracy and was used for comparison with BMO-MRW. Distinguishing perimetric glaucoma, RNFLT and BMO-MRW showed comparable AUROCs in global (AUROC, 95% confidence interval: 0.954, 0.911-0.996 and 0.929, 0.872-0.986) and sectoral (0.929, 0.877-0.981 and 0.946, 0.904-0.996) analysis. For preperimetric glaucoma BMO-MRW and RNFLT also demonstrated comparable performance in global (0.839, 0.757-0.921 and 0.821, 0.731-0.912) and sectoral (0.860, 0.782-0.938 and 0.835, 0.750-0.920) analysis. When identifying ocular hypertensive eyes AUROCs were lower for global RNFLT and BMO-MRW (0.493, 0.365-0.621 and 0.562, 0.433-0.691). A combined parameter showed an AUROC of 0.959, 0.921 to 0.996 for perimetric and 0.849, 0.770 to 0.929 for preperimetric glaucoma. CONCLUSIONS: Bruch's membrane opening-MRW and RNFLT are comparably useful parameters for discrimination of preperimetric and perimetric glaucomatous eyes and show potential to assist each other in glaucoma diagnosis. (www.ClinicalTrials.gov number, NTC00494923; Erlangen Glaucoma Registry.).

Confocal Laser Scanning Tomography to Predict Visual Field Conversion in Patients With Ocular Hypertension and Early Glaucoma.

PURPOSE: To compare Moorfields regression analysis (MRA), Glaucoma probability score (GPS), and different discriminant functions to predict future visual field conversion of patients with ocular hypertension and early glaucoma. PATIENTS AND METHODS: The study included 120 eyes of patients with ocular hypertension and 110 eyes of patients with early glaucoma from the Erlangen glaucoma registry. Annually, all patients underwent standard automated perimetry, 24-hour intraocular pressure profile, optic disc photography, and HRT (Heidelberg Retina Tomograph I-III; Heidelberg Engineering) measurements. The cohort was divided into 2 groups based on the development of repeatable glaucomatous visual fields. Positive predictive values and negative predictive values were compared for MRA, GPS, and the classification of Bathija, Iester, Mardin, and Mikelberg at baseline. Kaplan-Meier Survival curves and Logrank tests were used to evaluate equality of survival distributions for different test results. RESULTS: Median follow-up was 9.04 years. 26 eyes (11.3%) demonstrated glaucomatous visual field loss in the follow-up. MRA temporal-superior and temporal-inferior outside normal limits were predictive of future visual field loss with positive predictive values of 33.3% and 28.6%. Normal GPS Temporal Sector demonstrated a negative predictive value of 96.4% and normal results in discriminant functions between 94.7% and 95.5%. CONCLUSIONS: Confocal scanning laser tomography is a useful imaging modality to predict future visual field conversion. Development of visual field defects in 10 years is highly unlikely, if GPS classification and/or classification of discriminant analysis at baseline are normal. MRA temporal-superior and temporal-inferior outside normal limits are associated with future VF conversion (ClinicalTrials.gov number, NCT00494923).

The Effect of Long-term Antiglaucomatous Drug Administration on Central Corneal Thickness.

PURPOSE: To evaluate rates of changes per year of central corneal thickness after antiglaucomatous drug administration with ß-blockers, prostaglandin analogs, and carbonic anhydrase inhibitors monotherapy and combined topical antiglaucomatous therapy, in a cohort of patients with ocular hypertension, glaucoma suspects, and patients with perimetric glaucoma as compared with normal controls. PATIENTS AND METHODS: This retrospective single-center study included 130 eyes as healthy controls, 121 eyes of ocular hypertensive patients, 105 eyes of glaucoma suspects, and 49 eyes of perimetric glaucoma patients. All patients underwent standard automated perimetry, 24-hour intraocular pressure profile, optic disc photography, and optical coherence pachymetry (OCP; Heidelberg Engineering). The cohort was divided into 8 groups on the basis of topical antiglaucomatous medication. Linear regression analysis was conducted to analyze the relationship between central corneal thickness and exposure to antiglaucomatous medication during the follow-up. RESULTS: Central corneal thickness did not change during the follow-up for investigated diagnostic subgroups. There was a statistically significant decrease in central corneal thickness for eyes treated with prostaglandin monotherapy (-3.1 µm/y for left eye), and a combined therapy with prostaglandins, carbonic anhydrase inhibitors, and ß-blockers (-5.8 and -3.8 µm/y for right and left eye, respectively). CONCLUSIONS: We recommend regular measurements before and during therapy with prostaglandin monotherapy and a combined therapy with prostaglandins, carbonic anhydrase inhibitors, and ß-blockers. Follow-up intraocular pressure measurements may be underestimated for eyes treated with the aforementioned treatment regimens if central corneal thickness is not measured on a regular basis.

Predicted and measured retinal nerve fiber layer thickness from time-domain optical coherence tomography compared with spectral-domain optical coherence tomography.

IMPORTANCE: New methods are needed to compare peripapillary retinal nerve fiber layer thickness (pRNFLT) measurements taken from time-domain optical coherence tomography (TD-OCT) and spectral-domain OCT (SD-OCT). OBJECTIVE: To compare the agreement of measured and predicted pRNFLT using different equations based on pRNFLT measurements obtained by TD-OCT and SD-OCT. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional single-center study that took place at the Department of Ophthalmology, University of Erlangen-Nuremberg from November 16, 2005, to June 3, 2015, and included 138 eyes of control participants, 126 eyes of patients with ocular hypertension, 128 eyes of patients with preperimetric glaucoma, and 160 eyes of patients with perimetric glaucoma. All participants had standard clinical examinations to obtain TD-OCT (via Stratus OCT) and SD-OCT (via Spectralis OCT) measurements of pRNFLT. Two groups were matched for diagnostic subgroup, eye side, sex, and age. The TD-OCT measurements of the first group were used to predict the mean SD-OCT and 6-sector vertical-split pRNFLT measurements of the second group and vice versa. The agreement between the predicted pRNFLT calculations of conversion equations and measured pRNFLT of the second group was evaluated by intraclass correlation coefficients and Bland-Altman plots. MAIN OUTCOMES AND MEASURES: Mean and sectoral pRNFLT measurements obtained by TD-OCT and SD-OCT as well as the agreement between measured and predicted pRNFLT. RESULTS: The agreement for all investigated equations to predict mean pRNFLT measurements with intraclass correlation coeffecients ranged from 0.937 to 0.939. Bland-Altman plots demonstrated systemic biases between -0.7 µm and +1.1 µm for measured and predicted mean pRNFLT measurements. The ratio method demonstrated an intraclass correlation coefficient of 0.969 for the temporal-inferior sector. The best color-code agreement between both OCT devices was achieved by the no conversion method, with κ = 0.731 (95% CI, 0.656-0.806) for the mean pRNFLT. CONCLUSIONS AND RELEVANCE: These data suggest that the prediction of mean pRNFLT values by equations derived from TD-OCT and SD-OCT can be conducted with high levels of agreement. In individual cases and singular sectors, high prediction errors may occur. When longitudinal imaging data from both TD-OCT and SD-OCT are available, conversion equations may provide longitudinal comparability.

Thickness related textural properties of retinal nerve fiber layer in color fundus images.

Images of ocular fundus are routinely utilized in ophthalmology. Since an examination using fundus camera is relatively fast and cheap procedure, it can be used as a proper diagnostic tool for screening of retinal diseases such as the glaucoma. One of the glaucoma symptoms is progressive atrophy of the retinal nerve fiber layer (RNFL) resulting in variations of the RNFL thickness. Here, we introduce a novel approach to capture these variations using computer-aided analysis of the RNFL textural appearance in standard and easily available color fundus images. The proposed method uses the features based on Gaussian Markov random fields and local binary patterns, together with various regression models for prediction of the RNFL thickness. The approach allows description of the changes in RNFL texture, directly reflecting variations in the RNFL thickness. Evaluation of the method is carried out on 16 normal ("healthy") and 8 glaucomatous eyes. We achieved significant correlation (normals: ρ=0.72±0.14; p≪0.05, glaucomatous: ρ=0.58±0.10; p≪0.05) between values of the model predicted output and the RNFL thickness measured by optical coherence tomography, which is currently regarded as a standard glaucoma assessment device. The evaluation thus revealed good applicability of the proposed approach to measure possible RNFL thinning.

Perimetric measurements with flicker-defined form stimulation in comparison with conventional perimetry and retinal nerve fiber measurements.

PURPOSE: We compared the results of flicker-defined form (FDF) perimetry with standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) thickness measurements using spectral domain optical coherence tomography (OCT). METHODS: A total of 64 healthy subjects, 45 ocular hypertensive patients, and 97 "early" open-angle glaucoma (OAG) patients participated in this study. Definition of glaucoma was based exclusively on glaucomatous optic disc appearance. All subjects underwent FDF perimetry, SAP, and peripapillary measurements of the RNFL thickness. The FDF perimetry and SAP were performed at identical test locations (G1 protocol). Exclusion criteria were subjects younger than 34 years, SAP mean defect (SAP MD) > 5 dB, eye diseases other than glaucoma, or nonreliable FDF measurements. The correlations between the perimetric data on one hand and RNFL thicknesses on the other hand were analyzed statistically. RESULTS: The age-corrected sensitivity values and the local results from the controls were used to determine FDF mean defect (FDF MD). The FDF perimetry and SAP showed high concordance in this cohort of experienced patients (MD values, R = -0.69, P < 0.001). Of a total of 42 OAG patients with abnormal SAP MD, 38 also displayed abnormal FDF MD. However, FDF MD was abnormal in 28 of 55 OAG patients with normal SAP MD. The FDF MD was significantly (R = -0.61, P < 0.001) correlated with RNFL thickness with a (nonsignificantly) larger correlation coefficient than conventional SAP MD (R = -0.48, P < 0.001). CONCLUSIONS: The FDF perimetry is able to uncover functional changes concurrent with the changes in RNFL thickness. The FDF perimetry may be an efficient functional test to detect early glaucomatous nerve atrophy. (ClinicalTrials.gov number, NCT00494923.).

Longitudinal analysis of progression in glaucoma using spectral-domain optical coherence tomography.

PURPOSE: To compare the longitudinal loss of RNFL thickness measurements by SD-OCT in healthy individuals and glaucoma patients with or without progression concerning optic disc morphology. METHODS: A total of 62 eyes, comprising 38 glaucomatous eyes with open angle glaucoma and 24 healthy controls, were included in the study (Erlangen Glaucoma Registry, NTC00494923). All patients were investigated annually over a period of 3 years by Spectralis SD-OCT measuring peripapillary RNFL thickness. By masked comparative analysis of photographs, the eyes were classified into nonprogressive and progressive glaucoma cases. Longitudinal loss of RNFL thickness was compared with morphological changes of optic disc morphology. RESULTS: Mixed model analysis of annual OCT scans revealed an estimated annual decrease of the RNFL thickness by 2.12 µm in glaucoma eyes with progression, whereas glaucoma eyes without progression in optic disc morphology lost 1.18 µm per year in RNFL thickness (P = 0.002). The rate of change in healthy eyes was 0.60 µm and thereby also significantly lower than in glaucoma eyes with progression (P < 0.001). The intrasession variability of three successive measurements without head repositioning was 1.5 ± 0.7 µm. The loss of mean RNFL thickness exceeded the intrasession variability in 60% of nonprogressive eyes, and in 85% of progressive eyes after 3 years. CONCLUSIONS: LONGITUDINAL MEASUREMENTS OF RNFL THICKNESS USING SD-OCT SHOW A MORE PRONOUNCED REDUCTION OF RNFL THICKNESS IN PATIENTS WITH PROGRESSION COMPARED WITH PATIENTS WITHOUT PROGRESSION IN GLAUCOMATOUS OPTIC DISC CHANGES. (www.clinicaltrials.gov number, NTC00494923.).

Glaucoma diagnostic performance of GDxVCC and spectralis OCT on eyes with atypical retardation pattern.

PURPOSE: To investigate the impact of typical scan score (TSS) on discriminating glaucomatous and healthy eyes by scanning laser polarimetry and spectral domain optical coherence tomography (SD-OCT) in 32 peripapillary sectors. PATIENTS AND METHODS: One hundred two glaucoma patients and 32 healthy controls underwent standard automated perimetry, 24-hour intraocular pressure profile, optic disc photography, GDxVCC, and SD-OCT measurements. For controls, only very typical scans (TSS=100) were accepted. Glaucoma patients were divided into 3 subgroups (very typical: TSS=100; typical: 99≥TSS≥80, atypical: TSS<80). Receiver operating characteristic curves were constructed for mean retinal nerve fiber layer values, sector data, and nerve fiber indicator (NFI). Sensitivity was estimated at ≥90% specificity to compare the discriminating ability of each imaging modality. RESULTS: For discrimination between healthy and glaucomatous eyes with very typical scans, the NFI and inferior sector analyses 26 to 27 demonstrated the highest sensitivity at ≥90% specificity in GDxVCC and SD-OCT, respectively. For the typical and atypical groups, sensitivity at ≥90% specificity decreased for all 32 peripapillary sectors on an average by 10.9% and 17.9% for GDxVCC and by 4.9% and 0.8% for SD-OCT. For GDxVCC, diagnostic performance of peripapillary sectors decreased with lower TSS, especially in temporosuperior and inferotemporal sectors (sensitivity at ≥90% specificity decreased by 55.3% and by 37.8% in the atypical group). CONCLUSIONS: Diagnostic accuracy is comparable for SD-OCT and GDxVCC if typical scans (TSS=100) are investigated. Decreasing TSS is associated with a decrease in diagnostic accuracy for discriminating healthy and glaucomatous eyes by scanning laser polarimetry. NFI is less influenced than the global or sector retinal nerve fiber layer thickness. The TSS score should be included in the standard printout. Diagnostic accuracy of SD-OCT is barely influenced by low TSS.

Analysis of visual appearance of retinal nerve fibers in high resolution fundus images: a study on normal subjects.

The retinal ganglion axons are an important part of the visual system, which can be directly observed by fundus camera. The layer they form together inside the retina is the retinal nerve fiber layer (RNFL). This paper describes results of a texture RNFL analysis in color fundus photographs and compares these results with quantitative measurement of RNFL thickness obtained from optical coherence tomography on normal subjects. It is shown that local mean value, standard deviation, and Shannon entropy extracted from the green and blue channel of fundus images are correlated with corresponding RNFL thickness. The linear correlation coefficients achieved values 0.694, 0.547, and 0.512 for respective features measured on 439 retinal positions in the peripapillary area from 23 eyes of 15 different normal subjects.

Detection of nerve fiber atrophy in apparently effectively treated papilledema in idiopathic intracranial hypertension.

BACKGROUND: Since papilledema in idiopathic intracranial hypertension is a passive event not primarily affecting the visual tract, resolution with restitution ad integrum is expected if intracranial pressure is rebalanced. Retinal nerve fiber swelling due to papilledema in the acute phase and possible axon loss after long-lasting elevated intracranial pressure was investigated in a controlled cross-sectional study by scanning laser polarimetry. METHODS: A cohort of 23 patients with idiopathic intracranial hypertension according to the modified Dandy diagnostic criteria, and 23 controls matched for age and gender were investigated. All patients received neurological and ophthalmologic examination including scanning laser polarimetry (GDx VCC). Patients were divided into groups depending on the presence of a papilledema (group 1) or the regression of the papilledema after initiation of therapy (group 2). Therapy was based on recommendations of the German Society of Neurology. RESULTS: Scanning laser polarimetry showed an increase of nerve fiber thickness in group 1, and a decrease of the nerve fiber thickness in group 2 compared to controls. Ten of 13 patients showed signs of a regional axon loss in the deviation map of the GDx report, and six had a Nerve Fiber Index above 30. All patients with regressive papilledema and coincidence of visual field damage and pale optic disc appearance had a pathologic result in the GDx examination, but only four of ten patients with a pathologic GDx examination showed coincidence of pale optic disc appearance and visual field damage as sign of underlying optic disc atrophy. CONCLUSION: In patients with apparently effective treatment of clinical symptoms and a regression of papilledema in idiopathic intracranial hypertension, a retinal axon loss was detected by scanning laser polarimetry. Axon loss was even present in patients without clinical evidence of optic nerve atrophy.