Cell Types of the Human Retina and Its Organoids at Single-Cell Resolution.

Human organoids recapitulating the cell-type diversity and function of their target organ are valuable for basic and translational research. We developed light-sensitive human retinal organoids with multiple nuclear and synaptic layers and functional synapses. We sequenced the RNA of 285,441 single cells from these organoids at seven developmental time points and from the periphery, fovea, pigment epithelium and choroid of light-responsive adult human retinas, and performed histochemistry. Cell types in organoids matured in vitro to a stable "developed" state at a rate similar to human retina development in vivo. Transcriptomes of organoid cell types converged toward the transcriptomes of adult peripheral retinal cell types. Expression of disease-associated genes was cell-type-specific in adult retina, and cell-type specificity was retained in organoids. We implicate unexpected cell types in diseases such as macular degeneration. This resource identifies cellular targets for studying disease mechanisms in organoids and for targeted repair in human retinas.

Vasoactive peptides as biomarkers for the prediction of retinopathy of prematurity.

BACKGROUND: Retinopathy of prematurity (ROP) is a major complication in preterm infants. We assessed if plasma levels of midregional pro-atrial natriuretic peptide (MR-proANP) and C-terminal pro-endothelin-1 (CT-proET1) serve as early markers for subsequent ROP development in preterm infants <32 weeks gestation. METHODS: Prospective, two-centre, observational cohort study. MR-proANP and CT-proET1 were measured on day seven of life. Associations with ROP ≥ stage II were investigated by univariable and multivariable logistic regression models. RESULTS: We included 224 infants born at median (IQR) 29.6 (27.1-30.8) weeks gestation and birth weight of 1160 (860-1435) g. Nineteen patients developed ROP ≥ stage II. MR-proANP and CT-proET1 levels were higher in these infants (median (IQR) 864 (659-1564) pmol/L and 348 (300-382) pmol/L, respectively) compared to infants without ROP (median (IQR) 299 (210-502) pmol/L and 196 (156-268) pmol/L, respectively; both P < 0.001). MR-proANP and CT-proET1 levels were significantly associated with ROP ≥ stage II in univariable logistic regression models and after adjusting for co-factors, including gestational age and birth weight z-score. CONCLUSIONS: MR-proANP and CT-proET1 measured on day seven of life are strongly associated with ROP ≥ stage II in very preterm infants and might improve early prediction of ROP in the future. IMPACT: Plasma levels of midregional pro-atrial natriuretic peptide and C-terminal pro-endothelin-1 measured on day seven of life in very preterm infants show a strong association with development of retinopathy of prematurity ≥ stage II. Both biomarkers have the potential to improve early prediction of retinopathy of prematurity. Vasoactive peptides might allow to reduce the proportion of screened infants substantially.

Primary Open-Angle Glaucoma Progression in Glaucoma Patients with Unchanged Topical Treatment over 3 Years - Retrospective Observational Cohort Analysis.

BACKGROUND: Lowering intraocular pressure (IOP) is a mainstay of glaucoma therapy. It is, however, still an open question whether a comparable level of long-term IOP lowering achieved by different medications results in comparable protection for the retinal ganglion cells. The purpose of this study was to retrospectively analyze glaucoma damage progression in two cohorts of primary open-angle glaucoma patients with different and unchanged therapy over a period of 3 years, and the main objective of this study was to determine possible differences in terms of structural [retinal nerve fiber layer thickness (RNFL)] and functional [visual field (VF)] outcome. PATIENTS AND METHODS: The retrospective observational cohort analysis compared two differently treated groups of glaucoma patients with their original, at study entry, topical therapy unchanged over 3 years. The main endpoint was the time course of RNFL thickness and VF mean defect (MD). RESULTS: Twenty-one eyes were included in each group. The first group (21 eyes) was on a fixed combination of timolol and dorzolamide twice a day and the second group on one drop of prostaglandin analog, either latanoprost alone (15 eyes) or travoprost alone (6 eyes), in an unchanged regimen over a period of 3 years. IOP in mmHg at baseline and at 36 months was 11.9 ± 2.4 and 13.0 ± 2.1 in the first, and 12.9 ± 3.0 and 14.1 ± 3.2 in the second group, respectively. RNFL thickness values in micrometers were at baseline and at 36 months 77.8 ± 12.3 and 76.6 ± 15.2 in the first, and 77.5 ± 15.2 and 72.8 ± 14.5 in the second group, respectively. VF MD in dB were 1.7 ± 2.5 and 1.2 ± 2.9 in the first, and 0.9 ± 2.3 and 0.7 ± 2.6 in the second group, respectively. CONCLUSION: Both groups had comparable baseline, as well as mean overall IOP. However, the course of IOP levels over time was different in the two groups, showing earlier and more pronounced long-term drift in the prostaglandin analog-treated group. RNFL thickness was comparable at baseline, however, RNFL thinning over time was more pronounced in the prostaglandin analog-treated group. There were no statistical differences between the groups in terms of VF MD at baseline and over time.

Retrospective Analysis of Prognostic Value of Optical Coherence Tomography Angiography for the Development of Glaucomatous Damage - One Year Follow-Up Retrospective Observational Cohort Analysis.

PURPOSE: Detecting glaucoma damage progression is an essential component of follow-ups in glaucoma patients. It is still unclear which of the currently available and routinely used parameters of glaucoma damage heralds the loss of retinal ganglion cells first. We analysed local hospital data on primary open-angle glaucoma (POAG) patients and looked for correlations between the optical coherence tomography (OCT) structural, OCT angiography (OCTA), and visual field (VF) parameters. PATIENTS AND METHODS: Results of eye examinations of POAG patients at baseline, 6 months, and 12 months were analysed. Inclusion criteria were, apart from the diagnosis of POAG, availability and quality of all modalities of examination data and no surgical intervention on the eyes during the observation period. Data on VF mean defect (MD), OCT peripapillary nerve fibre layer (RNFL), OCT macular ganglion cell layer, and OCTA, peripapillary and in the macula, were parameters of interest. Correlations of structural (OCT and OCTA) on one, and functional parameters (VF MD) on the other side, at baseline and as changing over time (first 6 months vs. second 6 months) were performed. RESULTS: All together, data from 78 eyes of 78 POAG patients were included in the analysis. Correlations at baseline were all highly significant (Spearman's r-coefficients between 0.31 and 0.8, all p < 0.05). None of the correlations of parameter changes over time were significant (all p > 0.05). CONCLUSION: Whereas a robust correlation was observed at baseline between the structural (OCT and OCTA) and functional (VF MD) parameters, none of the examination modality could predict a change in the other modalities during the 1-year period. Results confirm the necessity of regularly performing both the structural and functional examinations in our glaucoma patients.

674 Cases of Late Postoperative Intraocular Lens Opacification of a Hydrophilic-Hydrophobic Acryl Intraocular Lens in Switzerland and Retrospective Opacification Risk Factor Assessment of 212 Cases.

PURPOSE: To report the prevalence of late postoperative opacification of a hydrophilic and hydrophobic acrylic intraocular lens (IOL) and to assess the risk factors in a subset of 212 eyes of patients referred to the University Eye Department in Basel, Switzerland. DESIGN: Retrospective case series. METHODS: A survey was performed at all large ophthalmological clinics in Switzerland regarding exchanged Lentis LS-502-1 lenses, and the number of affected eyes was counted. Moreover, consecutive patients who were referred to a tertiary clinic between September 2015 and November 2016 with Lentis LS-502-1 opacification were investigated. Peri- and postoperative charts, medical history, and topical and systemic medications were assessed. RESULTS: A total of 674 opacified Lentis LS-502-1 lenses have been reported in Switzerland, and 212 consecutive eyes of 182 patients were included in the study. All IOLs had a similar pattern of opacification with a yellowish, diffuse appearance, and most of them showed a small, paracentral, roundish area that was less affected or not at all. Arterial hypertension (73%), hypercholesterolemia (34%), and diabetes (21%) were the main associated systemic diseases, and statins (34%) and betablockers (34%) were the main treatments used. CONCLUSIONS: The prevalence of IOL opacification was 9.9%. No associated systemic eye disease or medications could be detected, which was implicated in the opacification process. The reason for opacification remains unclear, but it seems to be unrelated to the patient's state; therefore, it is attributed to primary calcification.

Feasibility and Safety of a Coaxial Dual-Wavelength Optical Coherence Tomography Apparatus.

PURPOSE: To evaluate the feasibility and safety of a coaxial dual-wavelength optical coherence tomography (OCT) device (marked as Hydra-OCT). METHODS: Healthy participants without ocular pathology underwent retinal imaging using the Hydra-OCT allowing for simultaneous measurement of retinal scanning of 840 and 1,072 nm wavelength. Before and after measurement, best-corrected visual acuity and patients' comfort were assessed. Representative OCT images from both wavelengths were compared by 5 independent graders using a subjective grading scheme. RESULTS: A total of 30 eyes of 30 participants (8 females and 22 males) with a mean age of 26.5 years (range from 19 to 55 years) were included. Dual-wavelength image acquisition was made possible in each subject. The participant's effort and comfort assessment using the Hydra-OCT imaging revealed an equivalent value as compared to the commercially available OCT machine. No adverse events were reported, and visual acuity was not altered by the Hydra-OCT. Imaging between the systems was comparable. CONCLUSIONS: This study provides evidence for the feasibility and safety of a coaxial dual-wavelength OCT imaging method under real-life conditions. The novel Hydra-OCT imaging device may offer additional insights into the pathology of retinal and choroidal diseases.

[Prospective Cohort Study of In-Hospital Patients Undergoing Ophthalmic Surgery for the Validation of ClassIntra: Classification of Intraoperative Adverse Events]. / Prospektive Kohortenstudie bei stationären augenchirurgischen Patienten für die Validierung der ClassIntra-Klassifikation für unerwünschte intraoperative Ereignisse.

BACKGROUND: To the best of our knowledge, there is no validated classification to assess intraoperative adverse events (iAEs) in ophthalmic surgery. ClassIntra is a newly developed classification for surgery- and anaesthesia-related iAEs that has been recently validated in various surgical disciplines, but not in ophthalmic surgery. We aim to assess the validity and practicability of ClassIntra in patients undergoing ophthalmic surgery. METHODS: A consecutive sample of in-hospital patients undergoing any type of ophthalmic surgery was included in this single-centre prospective cohort study. iAEs were classified using ClassIntra, consisting of 5 severity grades according to the symptoms of the patient and the required treatment. All patients were followed for two weeks to record all postoperative adverse events according to Clavien-Dindo. The primary endpoint was the risk-adjusted association between the most severe iAE and the weighted sum of all postoperative adverse events within the two-week follow-up using the Comprehensive Complication Index (CCI). In addition, ophthalmologists and anaesthesiologists were asked to complete an online survey assessing the severity of iAEs for 10 fictitious clinical case scenarios. Reliability was assessed by comparing the clinicians' ratings to the prespecified benchmark rating of the study team. RESULTS: In this study, 100 in-hospital patients with an average age of 64 years (SD 15) were included. The majority of all patients were ASA II (n = 53, 53%) or III (n = 42, 42%). Thirty-two iAEs were recorded in 22 patients (17 grade I, 12 grade II, 3 grade III). Ninety-four postoperative adverse events occurred in 50 patients (44 grade I, 36 grade II, 14 grade IIIa). We found a mean difference in CCI of 2,1 (95% confidence interval [CI] - 2,5 to 6,8) per one unit increase in severity grades of ClassIntra. Fifty ophthalmologists and anaesthesiologists completed the online survey (response rate 54%). The intraclass correlation coefficient was 0,79 (95% CI 0,64 to 0,94). CONCLUSIONS: The application of ClassIntra during daily routine in ophthalmic surgery showed the usefulness and practicability of this classification for the standardised assessment of intraoperative adverse events. Although construct validity could not be demonstrated, the good reliability in the survey's rating underlines the criterion validity of this newly developed classification in ophthalmic surgery.

THREE-DIMENSIONAL ANALYSIS OF SUBMACULAR PERFORATING SCLERAL VESSELS BY ENHANCED DEPTH IMAGING OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: To analyze submacular perforating scleral vessels (PSVs) using enhanced depth imaging spectral domain optical coherence tomography (EDI-SDOCT). METHODS: Twenty-two eyes of 11 healthy women were included in this retrospective study. Central EDI-SDOCT scans (3 × 4.5 × 1.9 mm, 13.5 mm scan area) were acquired and postprocessed by denoising, manual sclera segmentation, and PSV investigated by five graders. RESULTS: Mean age was 22.4 ± 6.2 years. Mean refractive error was -0.44 ± 0.8 diopters. Mean axial length was 23.08 ± 0.63 mm. The coefficient of agreement for grading was good. Mean number of submacular PSVs was 0.33 ± 0.2 per mm (range from 0 to 9 per eye). Subfield analysis showed 0.2 ± 0.5 (range 0-2) and 2.1 ± 1.8 (range 0-7) vessels, respectively, for central 1-mm diameter and 3-mm diameter. Quadrant analysis showed 0.7 ± 0.9, 0.5 ± 0.9, 0.3 ± 0.6, and 0.4 ± 0.6 vessels, respectively for superior, inferior, nasal, and temporal quadrants. Total number of PSV showed no significant side difference (median difference 0.5, confidence interval -3.0 to 3.0, P = 0.94) or an influence of axial length (P = 0.16). CONCLUSION: This is the first description of three-dimensional EDI-SDOCT visualization of submacular PSV in healthy eyes. This method allows for in vivo imaging of a critical component of outer retinal perfusion at the posterior pole.

A pilot study to image the vascular network of small melanocytic choroidal tumors with speckle noise-free 1050-nm swept source optical coherence tomography (OCT choroidal angiography).

PURPOSE: To visualize and measure the vascular network of melanocytic choroidal tumors with speckle noise-free swept source optical coherence tomography (SS-OCT choroidal angiography). METHODS: Melanocytic choroidal tumors from 24 eyes were imaged with 1050-nm optical coherence tomography (Topcon DRI OCT-1 Atlantis). A semi-automated algorithm was developed to remove speckle noise and to extract and measure the volume of the choroidal vessels from the obtained OCT data. RESULTS: In all cases, analysis of the choroidal vessels could be performed with SS-OCT without the need for pupillary dilation. The proposed method allows speckle noise-free, structure-guided visualization and measurement of the larger choroidal vessels in three dimensions. The obtained data suggest that speckle noise-free OCT may be more effective at identifying choroidal structures than traditional OCT methods. The measured volume of the extracted choroidal vessels of Haller's layer and Sattler's layer in the examined tumorous eyes was on average 0.982463955 mm(3) /982463956 µm(3) (range of 0.209764406 mm(3) /209764405.9 µm(3)to 1.78105544 mm(3) /1781055440 µm(3)). Full thickness obstruction of the choroidal vasculature by the tumor was found in 18 cases (72 %). In seven cases (18 %), choroidal vessel architecture did not show pronounced morphological abnormalities (18 %). CONCLUSION: Speckle noise-free OCT may serve as a new illustrative imaging technology and enhance visualization of the choroidal vessels without the need for dye injection. OCT can be used to identify and evaluate the choroidal vessels of melanocytic choroidal tumors, and may represent a potentially useful tool for imaging and monitoring of choroidal nevi and melanoma.

Inter-device size variation of small choroidal nevi measured using stereographic projection ultra-widefield imaging and optical coherence tomography.

PURPOSE: Our purpose was to compare the tumor sizes of small choroidal nevi using ultra-widefield imaging (UWF) and different optical coherence tomography systems. METHODS: Thirteen choroidal nevi were measured using automatic and manual segmentation techniques, including enhanced depth imaging spectral-domain optical coherence tomography (EDI-SDOCT) and 1050 nm swept source OCT (SSOCT), to compare to measurements obtained using the Optos projection ultra-widefield fundus (UWF) imaging technique. Segmentation artifacts were evaluated for all 13 cases, alongside an additional 12 choroidal nevi, using SSOCT. RESULTS: In tumor eyes, segmentation artifacts for the choroid-sclera interface were found in 42 % of SSOCT scans. EDI-SDOCT can underestimate tumor dimensions and differs up to -8.41 % compared to UWF imaging and by 1.25 % compared to SSOCT cases. The horizontal length of the nevi showed an average difference between EDI-SDOCT and SSOCT of ± 9.38 %. Measured markers showed an average difference in length of ± 12.51 %. The average tumor thickness showed a difference of ± 11.47 %. Comparisons between EDI-SDOCT/UWF, SSOCT/EDI-SDOCT, and marker EDI-SDOCT/SSOCT showed significant mean differences of -122 µm (CI: -212 to -31 µm, p = 0.013), 134 µm (CI: 65-203 µm, p = 0.0012), and -193 µm (CI: -345 to -41 µm, p = 0.017), whereas SSOCT/UWF showed no significant difference with a measurement of 13 µm (CI: -69-95 µm, p = 0.74). CONCLUSIONS: Automatic segmentation of nevi requires much caution, because a choroidal tumor can trigger many artifacts. It would be beneficial to monitor choroidal nevi using the same type of OCT technology, because a tumor is displayed differently.

Autologous internal limiting membrane transplantation achieves anatomic closure and functional improvement in the treatment of large, persistent macular holes.

PURPOSE: To evaluate the clinical outcome of subretinal autologous internal limiting membrane (ILM) transplantation during pars-plana vitrectomy for persistent full-thickness macular hole (FTMH) repair. METHODS: Retrospective, consecutive case series of 13 eyes (13 patients) undergoing small-incision vitrectomy with ILM transplantation and air tamponade for large persistent FTMH after prior unsuccessful vitrectomy with posterior hyaloid detachment and ILM peeling. MAIN OUTCOME MEASUREMENTS: For all eyes, high-definition spectral domain optical coherence tomography scans (SD-OCT Spectralis, Heidelberg Engineering GmbH, Germany) of the macula were routinely performed before surgery, 1 and 4 weeks after surgery, and at the final follow-up visit. Additionally, age, gender, axial length, macular hole diameter, biomicroscopic fundus evaluation and best-corrected visual acuity (BCVA) at baseline, 1 and 4 weeks after surgery, and at the final follow-up visit were analyzed. RESULTS: Anatomic closure was achieved in all 13 cases (100% success rate). Closure pattern was classified in accordance with to Rossi et al. (Graefe's Arch Clin Exp Ophthalmol 258(12):2629-2638, 2020). Mean baseline BCVA logMAR was 0.93, mean postoperative BCVA logMAR was 0.66 with a mean postoperative follow-up period of 11.4 months. No re-opening occurred during the observation period. CONCLUSIONS: Placing an autologous ILM-transplant in the subretinal space beneath the margin of the FTMH can support anatomic restauration and functional improvement in large, persistent FTMHs.

Human selection bias drives the linear nature of the more ground truth effect in explainable deep learning optical coherence tomography image segmentation.

Supervised deep learning (DL) algorithms are highly dependent on training data for which human graders are assigned, for example, for optical coherence tomography (OCT) image annotation. Despite the tremendous success of DL, due to human judgment, these ground truth labels can be inaccurate and/or ambiguous and cause a human selection bias. We therefore investigated the impact of the size of the ground truth and variable numbers of graders on the predictive performance of the same DL architecture and repeated each experiment three times. The largest training dataset delivered a prediction performance close to that of human experts. All DL systems utilized were highly consistent. Nevertheless, the DL under-performers could not achieve any further autonomous improvement even after repeated training. Furthermore, a quantifiable linear relationship between ground truth ambiguity and the beneficial effect of having a larger amount of ground truth data was detected and marked as the more-ground-truth effect.