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Purpose: To evaluate the performance of corneal epithelial thickness mapping (ETM) and demonstrate simultaneous measurement of ETMs and corneal topography using REVO NX (Optopol Technology, Zawiercie, Poland)-an OCT device for anterior and posterior segment imaging., Methods: One hundred thirty-seven eyes of 137 normal subjects and patients with corneal diseases were recruited to the study. Each subject was scanned with REVO NX. ETMs and corneal topography maps were reconstructed from a single measurement. Corneal topography was also carried out using Pentacam (Oculus, Wetzlar, Germany). One hundred twenty-eight eyes were qualified for the final analysis. Forty healthy eyes were used to evaluate the performance of ETM, and 88 eyes were used to compare ETMs and corneal topography. The repeatability and reproducibility of ETMs in healthy subjects were assessed on the basis of 17 spatial zones derived from an 8-mm diameter corneal scan using within-subject standard deviation, test-retest repeatability, within-subject coefficient of variation (CoV), and intraclass correlation coefficient (ICC)., Results: The ICC for both repeatability and reproducibility of ETMs for the central sector was 0.95. The ICC value for the other sectors was only moderately lower. However, the CoV for repeatability (≤1.55%) was slightly higher than the value reported for the RTVue device (Optovue, Inc, Fremont, California, USA), for which a CoV in the central zone of 1.07% was reported in unoperated eyes. The superior quadrants were found to be the thinnest while the inferior ones were the thickest. ETMs and topography maps created from a single OCT measurement present a complementary image of the cornea., Conclusions: ETMs obtained using REVO NX show high levels of repeatability and reproducibility in normal eyes. Because the topographic and epithelial thickness analyses are performed using the same data, which means they are based on the exact same 3D corneal model, they do not require reciprocal centration and map matching. This ensures a complete point-to-point correlation between ETMs and corneal topography maps, which paints a fuller picture of a given pathology., Competing Interests: The author declares that he has no conflicts of interest and no commercial relationship with Optopol Technology and Oculus. Dr. Sikorski has provided clinical consultation to Optopol Technology, free of charge., (Copyright © 2022 Bartosz L. Sikorski.)

Purpose: To compare the results obtained with two threshold strategies of visual field assessment: Humphrey SITA Fast (SFA) (Carl Zeiss Meditec) and PTS 2000 Advanced Threshold (ADV) (Optopol Technology) in healthy subjects and patients with glaucoma., Methods: The study sample comprised of 53 healthy volunteers and 69 patients with glaucoma. One eye of each patient was examined with the SFA and ADV strategies. The quantitative comparisons of test duration and global indices were made using correlation coefficients. The sensitivity and specificity of the algorithms were evaluated based on the GHT results and the adjusted Anderson-Patella (A&P) criteria., Results: The ADV test duration was shorter both in healthy subjects (by 5%) and patients with glaucoma (by 18%). The mean differences in MS values between the SFA and the ADV strategies were 1.06 ± 1.13 dB (MS SFA -MS ADV ) in healthy subjects and 1.00 ± 1.92 dB (MS SFA -MS ADV ) in patients with glaucoma. The MD index of ADV tests was lower than the SFA in the healthy (-0.74 ± 1.09 dB) (MS SFA -MS ADV ) and glaucoma group (-0.85 ± 2.19 dB) (MS SFA -MS ADV ). The mean differences in PSD values determined using both methods were -0.86 ± 0.67 dB (PSD SFA -PSD ADV ) and -0.53 ± 1.48 dB (PSD SFA -PSD ADV ) in healthy subjects and patients with glaucoma, respectively. Analysis of receiver operating characteristic curves built from MD and PSD indices show bigger area under curve in SFA than in ADV (0.983 vs.0.968 and 0.986 vs. 0.938, respectively). The GHT-based sensitivity and specificity for the ADV strategy were 92.75% and 77.36%, respectively, as compared to 92.75% and 90.57%, respectively, for the SFA strategy., Conclusions: Both SFA and ADV enable effective identification of glaucomatous defects within 5 minutes. The ADV strategy, however, is significantly faster. The correlation between the global indices of SFA and ADV is very high. Both strategies offer very high sensitivity when using both GHT and A&P criteria., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Bartosz L. Sikorski and Adriana Laudencka.)

Purpose: To present a new method of measuring ocular axial dimensions, termed OCT biometry (B-OCT)., Design: Observational cross-sectional study and evaluation of new diagnostic technology., Methods: B-OCT was implemented in the spectral domain OCT device for posterior and anterior segment imaging (REVO NX, Optopol Technology). A total of 349 eyes (214 of healthy subjects, 115 of patients with cataract, and 20 with severe macular diseases) were enrolled in the study. The results of B-OCT were compared to swept source OCT-based IOLMaster 700 (Carl Zeiss Meditec). Differences in measurement values between the two biometers were determined using the paired t -test. Agreement was assessed through intraclass correlation coefficients (ICCs) and Bland-Altman plots., Results: B-OCT obtained with REVO NX provides excellent interobserver reproducibility (ICC for: axial length (AXL) = 1.000; central corneal thickness (CCT) = 0.933; anterior chamber depth (ACD) = 0.933; lens thickness (LT) = 0.985) and intraobserver repeatability (ICC for: AXL = 1.000; CCT ≥ 0.994; ACD = 0.998; LT ≥ 0.993). The correlation between measurements made using both devices was outstanding (ICC for: AXL, healthy = 1.000; AXL, cataractous = 1.000; ACD, healthy = 0.998; ACD, cataractous = 0.997; LT, healthy = 0.998; LT, cataractous = 0.997; CCT, healthy = 0.989; CCT, cataractous = 0.979). The mean AXL measurement difference in healthy eyes was -0.001 ± 0.016 mm (the 95% LoA ranged from -0.034 to 0.031); mean ACD difference was 0.000 ± 0.024 mm (95% LoA, -0.047 to 0.047); mean LT difference was -0.002 ± 0.024 mm (95% LoA, -0.050 to 0.046); and mean CCT difference  was -0.8 ± 5.1  μ m (95% LoA, -10.81 to 9.26). The mean AXL measurement difference in cataractous eyes was -0.003 ± 0.022 mm (95% LoA, -0.046 to 0.039); mean ACD difference was 0.003 ± 0.029 mm (95% LoA, -0.054 to 0.059); mean LT difference was -0.002 ± 0.025 (95% LoA, -0.051 to 0.048); and mean CCT difference was 2.7 ± 6.4  μ m (95% LoA, -9.80 to 15.7)., Conclusion: The study shows small, nonsignificant differences between the biometric measurements obtained with REVO NX B-OCT and IOLMaster 700, which is of high significance for IOL power selection. As B-OCT utilizes a conventional OCT device, the measurements of the ocular axial dimensions are combined with high-resolution macular scans for the simultaneous assessment of central retina as a part of screening for macular pathology. The presented method is the first spectral domain OCT-based biometry technique and the only one integrated into a standard OCT device. Thus, it brings novel functionality to OCT technology., Competing Interests: The authors declare that they have no conflicts of interest.

Purpose. To evaluate the spatial distribution of photoreceptor inner and outer segment junction (IS/OS) reflectivity changes after successful vitrectomy for macula-off retinal detachment (PPV-mOFF) using spectral domain optical coherence tomography (SdOCT). Methods. Twenty eyes after successful PPV-mOFF were included in the study. During a mean follow-up period of 15.3 months, SdOCT was performed four times. To evaluate the IS/OS reflectivity a four-grade scale was used. Results. At the first follow-up visit the IS/OS had very similar reflectivity in entire length of the central scan with total average value of 1,05. At the second visit the most significant increase of the reflectivity was observed in temporal and nasal parafovea with average values of 2,17 and 2,22, respectively. The third region of increased reflectivity of an average value of 2,33 appeared during the third follow-up visit and was located in the foveola. At the last follow-up visit in entire central cross section the IS/OS reflectivity exceeded grade 2 reaching the highest average values in nasal and temporal parafovea and foveola. Conclusions. A gradual increase of the IS/OS reflectivity was observed in eyes after PPV-mOFF. The process is not random and starts independently in the peripheral and central part of the macula which may be attributed to the variable regenerative potential of cones and rods.