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Verification with RANSAC has become a crucial step for local feature-based matching applications in machine vision. Details of its implementation are directly relevant to time consumption and the quality of the estimated results. A novel method of robust model estimation for matched images with a large viewpoint change, namely Random Sample Consensus Based on Data Filter and Simulated Annealing, FSASAC in short, is introduced. FSASAC begins by filtering out most outliers according to their distributions, and then adjusts the sample probability of matched pairs by Simulated Annealing in the process of iteration. The process of sampling ceased until the current best hypothesis met with the termination conditions. Finally, FSASAC is presented experimentally, both on synthesized data and image pairs. Choose some modified methods as the comparative objectives. The results indicate that FSASAC can estimate the optimal model from image pairs with lower number of iterations and run-time under the condition of large viewpoint change, even when the outlier ratio is higher than 90%.

More than 6 million small-incision lenticule extraction (SMILE) procedures have been performed worldwide since 2011. Therefore, its long-term safety and efficacy should be investigated. This study aimed to evaluate 10-year refractive outcomes, corneal stability, axial length, and wavefront aberrations in patients who underwent SMILE to correct myopia. Thirty two patients (32 eyes) who underwent SMILE-based myopic correction. Corrected distance visual acuity, uncorrected distance visual acuity, corneal stability, axial length, and wavefront aberrations were evaluated preoperatively and at 1 month and 1, 5, and 10 years postoperatively. At 10 years postoperatively, the safety and efficacy indices for the patients included in this study were 1.19 ± 0.21 and 1.04 ± 0.27, respectively. For 26 (81%) and 30 eyes (94%), correction to within ±0.50 D and ±1.00 D of the target was achieved, respectively. Over the 10-year follow-up duration, a mean −0.32 ± 0.56 D regression was observed (−0.03 ± 0.06 D/year). Relative to baseline, horizontal and vertical comas significantly increased, as did the incidence of higher-order aberrations (all P < 0.001), whereas axial length and corneal elevation remained stable during follow-up. These results indicate that the SMILE-based correction for myopia of up to -10 Dioptres is safe, effective, and stable, with relatively constant wavefront aberrations and corneal stability over time after treatment. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to investigate the changes in the retina and choroid of children after 650 nm low-level red light therapy (LLRLT). Methods: In this prospective study, 25 subjects in the Shanghai Eye and ENT Hospital of Fudan University were included from August 2021 to September 2021. One eye was randomly selected to receive LLRLT for 3 min. Swept-source optical coherence tomography (OCT) and OCT angiography were used to measure retinal fovea perfusion density (RFPD), retinal fovea thickness (RFT), choroidal fovea blood flow (CFBF), and choroidal fovea thickness (CFT) before LLRLT, 5 min and 1 h after LLRLT. Baseline characteristics between LLRLT and non-LLRLT eyes were compared. Changes in the retinal and choroidal parameters were analyzed by ANCOVA models. SAS software was used for data analysis. The difference was considered statistically significant if p < 0.05. Results: There was no difference in baseline characteristics between LLRLT eyes and non-LLRLT eyes. The RFPD in LLRLT eyes significantly increased 5 min after LLRLT, and the increment was 1.70 ± 0.83% (p = 0.0389). The RFPD significantly decreased from 5 min to 1 h after LLRLT with a mean of −2.62 ± 0.86% decrement (p = 0.0031). The RFPD levels returned to baseline at 1 h after LLRLT (p = 0.8646). However, compared with insignificant RFPD changes in non-LLRLT eyes, there was no significant difference in RFPD changes at any sampling point. No significant changes in RFT, CFBF, and CFT were found in LLRLT eyes at each sampling point. Conclusion: Although 3 min of LLRLT has no effect on the choroid, it may cause a short-term transient increase in RFPD. It will provide theoretical support for the role of LLRLT in myopia control. [ABSTRACT FROM AUTHOR]