When segmenting intraretinal layers from multiple optical coherence tomography (OCT) images forming a mosaic or a set of repeated scans, it is attractive to exploit the additional information from the overlapping areas rather than discarding it as redundant, especially in low contrast and noisy images. However, it is currently not clear how to effectively combine the multiple information sources available in the areas of overlap. In this paper, we propose a novel graph-theoretic method for multi-surface multi-field co-segmentation of intraretinal layers, assuring consistent segmentation of the fields across the overlapped areas. After 2-D en-face alignment, all the fields are segmented simultaneously, imposing a priori soft interfield-intrasurface constraints for each pair of overlapping fields. The constraints penalize deviations from the expected surface height differences, taken to be the depth-axis shifts that produce the maximum cross-correlation of pairwise-overlapped areas. The method’s accuracy and reproducibility are evaluated qualitatively and quantitatively on 212 OCT images (20 nine-field, 32 single-field acquisitions) from 26 patients with glaucoma. Qualitatively, the obtained thickness maps show no stitching artifacts, compared to pronounced stitches when the fields are segmented independently. Quantitatively, two ophthalmologists manually traced four intraretinal layers on 10 patients, and the average error (4.58±1.46 μm) was comparable to the average difference between the observers (5.86±1.72 μm). Furthermore, we show the benefit of the proposed approach in co-segmenting longitudinal scans. As opposed to segmenting layers in each of the fields independently, the proposed co-segmentation method obtains consistent segmentations across the overlapped areas, producing accurate, reproducible, and artifact-free results.

The technique of cataract extraction with IOL placement and anterior prolapse of the optic through the anterior capsulorhexis shows promise to be a safe and viable option for pediatric patients with chronic uveitis treated with systemic immunotherapy.

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Background-Although the flipped classroom model provides an effective way to teach ophthalmology to medical students, there are concerns that it overburdens the learner. The purpose of this study was to assess medical students' perceptions of a case-based flipped classroom style compared with a traditional didactic lecture series and to evaluate the effects of case-based learning on students' confidence in managing common ophthalmic complaints.Methods-We created an interactive, case-based flipped classroom ophthalmology curriculum. Paired pre-and post-clerkship surveys were distributed to students on the first and last day of the 2-week clerkship. Questions were formatted as statements using a 6-point Likert scale to assess students' prior exposure to a flipped classroom, perceptions of the flipped classroom curriculum, and confidence in evaluating ophthalmic complaints.Results-A total of 75 students were included during the period July 2019 to March 2020. Pre-clerkship questionnaires revealed no preference for either teaching modality. Wilcoxon signed-rank testing comparing pre-and post-clerkship data revealed a significant increase in students' favoring the case-based flippedclassroom model. Participants reported significant reductions in pressure to perform, course burden, and overall anxiety as well as increased confidence in triaging common eye complaints.Conclusions-The case-based flipped classroom modality prioritizes key learning objectives while increasing student participation and confidence. The reproducibility and accessibility of standardized prepared video lectures and cases may help institutions to better incorporate ophthalmology into preexisting rotations.