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PurposeTo evaluate the potential for artificial intelligence-based video analysis to determine surgical instrument characteristics when moving in the three-dimensional vitreous space.MethodsWe designed and manufactured a model eye in which we recorded choreographed videos of many surgical instruments moving throughout the eye. We labeled each frame of the videos to describe the surgical tool characteristics: tool type, location, depth, and insertional laterality. We trained two different deep learning models to predict each of the tool characteristics and evaluated model performances on a subset of images.ResultsThe accuracy of the classification model on the training set is 84% for the x-y region, 97% for depth, 100% for instrument type, and 100% for laterality of insertion. The accuracy of the classification model on the validation dataset is 83% for the x-y region, 96% for depth, 100% for instrument type, and 100% for laterality of insertion. The close-up detection model performs at 67 frames per second, with precision for most instruments higher than 75%, achieving a mean average precision of 79.3%.ConclusionsWe demonstrated that trained models can track surgical instrument movement in three-dimensional space and determine instrument depth, tip location, instrument insertional laterality, and instrument type. Model performance is nearly instantaneous and justifies further investigation into application to real-world surgical videos.Translational relevanceDeep learning offers the potential for software-based safety feedback mechanisms during surgery or the ability to extract metrics of surgical technique that can direct research to optimize surgical outcomes.

Purpose: To report the anatomic outcomes and retinal structure changes from lens-sparing vitrectomy (LSV) for eyes with Stage 3 or 4 familial exudative vitreoretinopathy (FEVR)., Methods: Overall, 133 consecutive eyes of 119 patients with Stage 3 (51 eyes) or 4 (82 eyes) FEVR who underwent LSV between January 2012 and May 2023 were retrospectively reviewed., Results: One hundred twenty-nine eyes (97.0%) achieved traction relief through one LSV operation. The extent of retinal detachment improved in 98 eyes (73.7%), remained stable in 32 eyes (24.1%), and progressed in three eyes (2.3%). At long-term follow-up, 39 (29.3%) and 60 (45.1%) eyes had completely or partially reattached retina, respectively. The median change of venular angle was 3.6° (95% CI, 3.5-10.5; P < 0.001) and -9.9° (95% CI, -15.8 to -4.6; P < 0.001) for temporal and nasal vessels, respectively. The mean disk-fovea distance was 0.3 papillary diameter shorter (95% CI, -0.4 to -0.2; P < 0.001), and the mean temporal venular arcade distance was 0.02 papillary diameter larger (95% CI, -0.16 to 0.21; P = 0.361)., Conclusion: These results suggest that LSV can relieve vitreoretinal traction and reattach the retina in late-stage FEVR eyes. Improvements in temporal and nasal venular angle and disk-fovea distance reflect positive retinal structure changes for patients., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Opthalmic Communications Society, Inc.)

Objective: To (i) correlate preoperative retinal nerve fibre layer (RNFL) thickness with visual parameters in patients with pituitary macroadenomas. (ii) study the predictive role of preoperative RNFL in visual outcome following surgery for pituitary macroadenomas (iii) correlate change in postoperative RNFL thickness (RNFLT) with visual outcome., Methods: Preoperative and post-operative RNFL thickness of thirty-three consecutive patients operated for pituitary macro adenoma between June 2022 and May 2023 were measured using Optical Coherence Tomography (OCT) and compared with standard visual examination findings and Magnetic Resonance Imaging (MRI) measurements., Results: A total of 66 eyes of 33 patients who underwent surgical excision of pituitary macro adenoma between June 2022 and May 2023 were studied. The mean age in years of the study group was 44.36 ± 13.77 and both sexes were equally represented (Male: Female = 16:17). RNFL thinning predominantly involved the temporal (51.21+/-15.19 μm) followed by nasal quadrants (62.67+/- 17.03 μm) and correlated well with the visual field (VF) deficit (p <0.001). Patients with severe disc pallor had extremely thin RNFL (less than 67 +/- 8.68 μm). Patients with moderate to severe visual acuity (VA) deficits had significantly thinner RNFLs (65.08±7.09) compared to patients with normal to mild impairment in vision. (83.185±1.2) (p<0.05). RNFL values were significantly thinner for patients with Wilson Grade C, D and E tumours (66.13 ±12.19 μm) compared to those in Grade A and B (77.67±22.12 μm). The mean preop RNFL of patients who showed post-operative improvement in vision was 87.025± 15.02 μm, of patients in whom vision remained static was 74.58 ±18.31 μm. The mean VA (Decimal) increased from a minimum of 0.60 at the pre-operative timepoint to a maximum of 0.68 at the post-operative timepoint. (Wilcoxon Test: V = 42.5, p = <0.001). The mean RNFLT (µm) increased from 77.14 μm at the pre-operative timepoint to 83.77 μm at the post-operative timepoint. (Wilcoxon Test: V = 218.0, p = <0.001). The mean change of RNFL in patients in whom vision improved was 3.6 μm and the mean change of RNFL in patients in whom vision remained static was 9.51 μm. Absence of postoperative visual improvement was noted despite postoperative RNFL thickness improvement in eyes which showed significant preoperative thinning of the nasal (<65 μm) and temporal (<52μm) quadrants., Conclusion: RNFL thinning corelates directly with visual acuity, visual field, and optic disc pallor. Patients with pituitary adenoma have preferential thinning of temporal and nasal quadrants. Visual outcome is better in patients with preserved RNFLT of values more than 82 +/- 5 μm. Reversal of RNFL thinning postoperatively need not necessarily correlate with visual improvement especially in patients who showed significant preoperative thinning of nasal and temporal quadrants., Competing Interests: Conflict of Interest Nil., (Copyright © 2024 Elsevier B.V. All rights reserved.)

It has been reported that the retinal vessel and macular region of the retina are displaced after macular hole (MH) surgery. However, there is no detailed information for correlations between retinal and choroidal displacements. We obtained optical coherence tomography angiography (OCTA) and en-face optical coherence tomography (OCT) images from 24 eyes to measure the retinal and choroidal vascular displacement before and after surgery. These images were merged into infrared images using blood vessel patterns. The same vascular bifurcation points were automatically selected for each follow-up image, and the displacements of the bifurcation points were analyzed as a vector unit for prespecified grid regions in a semi-automated fashion. The results showed displacements of the choroidal intermediate vessels and retinal vessels following MH surgery (p = 0.002, p < 0.001). The topographic changes showed inferior, nasal, and centripetal displacement of the retina and inferiorly displaced choroid. The ILM peeling size and basal MH size were significantly associated with the retinal displacement (p < 0.001 and p = 0.010). Additionally, changes in the amount of the choroidal displacement were significantly correlated with that of the retinal displacements (p = 0.002). Clinicians should keep in mind that there might be topographic discrepancies of the displacement between retina and choroid when analyzing them following surgery., (© 2024. The Author(s).)

Purpose: The effect of carotid artery stenting in patients with unilateral carotid artery stenosis on the retina and choroid was evaluated using swept-source optical coherence tomography angiography (SS-OCTA)., Methods: SS-OCTA examination was conducted before stenting and 4 days and 3 months after stenting. The retinal nerve fiber layer, ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer, superficial vascular complex (SVC), deep vascular complex (DVC), choroidal vascular volume (CVV), and choroidal vascular index were measured. Repeated-measures analysis of variance was performed to assess the impact of carotid artery stenting on optical coherence tomography angiography (OCTA) metrics., Results: At baseline, 303 eyes from 160 patients (61.82 ± 9.98 years; 85.29% males) were enrolled. SVC and DVC densities and CVV were lower in ipsilateral eyes (stenosed side) compared to contralateral eyes (all P < 0.05). Four days after stenting, a significant increase was seen in SVC density in ipsilateral eyes (P < 0.05) while a significant increase was seen in CVV in ipsilateral eyes and contralateral eyes (both P < 0.05). Three months after stenting (63 patients with 114 eyes), a significant decrease was seen in the GCIPL thickness of ipsilateral and contralateral eyes (all P < 0.001)., Conclusions: Short term after carotid artery stenting, ipsilateral eyes showed a rapid and significant increase in SVC density and CVV., Translational Relevance: Optical coherence tomography (OCT)/OCTA measurements may have the potential to detect retinal and choroidal changes after stenting. Future research on the long-term effect of stenting on the retina and choroid will be guided by these findings.

This study aimed to assess retinal alterations following membrane peeling procedures using novel ILM Forceps with laser ablated surface with the help of intraoperative optical coherence tomography (iOCT). A post-hoc analysis was performed to evaluate iOCT findings in eyes that underwent membrane peeling procedures with the novel ILM Forceps. Pre-peel and post-peel iOCT videos and images were evaluated for each eye to assess for post-peel anatomic alterations. Surgical video/iOCT scan correlation was conducted to evaluate the etiology of anatomic alterations. Thirty-two eyes were included in the analysis. Three eyes (9%) had focal full thickness retinal elevations identified on iOCT following tissue-instrument interaction with the ILM Forceps. Two eyes (6%) had focal inner retinal elevations and one eye (3%) had a full-thickness retinal elevation that were not related to direct tissue-instrument interaction but rather indirect peeling forces. iOCT-identified architectural alterations related to direct-tissue instrument interaction were relatively infrequent (< 10%) with similar frequency to previously reported alterations with other surgical instruments., (© 2024. The Author(s).)

Introduction: Postoperative delirium in older people may result from the interaction between intrinsic brain vulnerability (e.g. neurodegeneration) and precipitating factors (e.g. surgery induced cytokines). Intrinsic brain vulnerability may be overt (e.g. Alzheimer's disease) or preclinical. In cognitively intact older people presenting for surgery, identification of preclinical neurodegeneration using bedside tools could aid postoperative delirium risk stratification. Thinning of the circumpapillary retinal nerve fibre layer thickness is associated with neurodegenerative disorders e.g. Alzheimer's disease. We propose that thinning of the retinal nerve fibre layer may be present some older people with postoperative delirium due to preclinical neurodegeneration, albeit to a lesser extent than in overt dementia., Objectives: The primary objective: Feasibility of acquiring usable retinal images with the hand-held optical coherence device, at the bedside of older, hip fracture surgery patients. Secondary objective: Comparison of the circumpapillary retinal nerve fibre layer thickness between people who did/did not have postoperative delirium. Proportion of exclusions due to retinal pathology., Method: Feasibility study involving 30, cognitively intact, older people recovering from hip fracture surgery. Retinal images were obtained using the hand-held optical coherence tomography device at the participants' bedside. Imaging was deferred in participants who had postoperative delirium., Results: Retinal images that could be assessed for circumpapillary retinal nerve fibre layer thickness were obtained in 26 participants (22 no postoperative delirium, 4 postoperative delirium). The mean circumpapillary retinal nerve fibre layer thickness was lower in the participants who had postoperative delirium compared to those who did not experience postoperative delirium (Mean (95% CI) of 76.50 (62.60-90.40) vs 89.19 (85.41-92.97) respectively)., Conclusion: Retinal imaging at the patient's bedside, using hand-held OCT is feasible. Our data suggests that the circumpapillary retinal nerve fibre layer may be thinner in older people who experience postoperative delirium compared to those who do not. Further studies are required., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Noah et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Various retinal diseases require subretinal and/or intravascular injections, which are precise and challenging ocular microsurgeries. Robot-assisted surgery is expected to promote surgery precision, visualization, and success rates. This review summarizes recent research progress on robot-assisted surgery for subretinal and intravascular injections, emphasizing effectiveness, safety, and intelligence, and aiming to provide valuable insights for research on the application of surgical robots in the treatment of retinal diseases.

Objective: To review recent technological advancement in imaging, surgical visualization, robotics technology, and the use of artificial intelligence in surgical vitreoretinal (VR) diseases., Background: Technological advancements in imaging enhance both preoperative and intraoperative management of surgical VR diseases. Widefield imaging in fundal photography and OCT can improve assessment of peripheral retinal disorders such as retinal detachments, degeneration, and tumors. OCT angiography provides a rapid and noninvasive imaging of the retinal and choroidal vasculature. Surgical visualization has also improved with intraoperative OCT providing a detailed real-time assessment of retinal layers to guide surgical decisions. Heads-up display and head-mounted display utilize 3-dimensional technology to provide surgeons with enhanced visual guidance and improved ergonomics during surgery. Intraocular robotics technology allows for greater surgical precision and is shown to be useful in retinal vein cannulation and subretinal drug delivery. In addition, deep learning techniques leverage on diverse data including widefield retinal photography and OCT for better predictive accuracy in classification, segmentation, and prognostication of many surgical VR diseases., Conclusion: This review article summarized the latest updates in these areas and highlights the importance of continuous innovation and improvement in technology within the field. These advancements have the potential to reshape management of surgical VR diseases in the very near future and to ultimately improve patient care., Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article., (Copyright © 2024 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to evaluate the impact of vitrectomy and posterior hyaloid (PH) peeling on color alteration of optic nerve head (ONH) and retina as a surrogate biomarker of induced perfusion changes., Methods: Masked morphometric and colorimetric analyses were conducted on preoperative (<1 month) and postoperative (<18 months) color fundus photographs of 54 patients undergoing vitrectomy, either with (44) or without (10) PH peeling and 31 years of age and gender-matched control eyes. Images were calibrated according to the hue and saturation values of the parapapillary venous blood column. Chromatic spectra of the retinal pigment epithelium and choroid were subtracted to avoid color aberrations. Red, green, and blue (RGB) bit values over the ONH and retina were plotted within the constructed RGB color space to analyze vitrectomy-induced color shift. Vitrectomy-induced parapapillary vein caliber changes were also computed morphometrically., Results: A significant post-vitrectomy red hue shift was noted on the ONH (37.1 degrees ± 10.9 degrees vs. 4.1 degrees ± 17.7 degrees, P < 0.001), which indicates a 2.8-fold increase in blood perfusion compared to control (2.6 ± 1.9 vs. 0.9 ± 1.8, P < 0.001). A significant post-vitrectomy increase in the retinal vein diameter was also noticed (6.8 ± 6.4% vs. 0.1 ± 0.3%, P < 0.001), which was more pronounced with PH peeling (7.9 ± 6.6% vs. 3.1 ± 4.2%, P = 0.002)., Conclusions: Vitrectomy and PH peeling increase ONH and retinal blood flow. Colorimetric and morphometric analyses offer valuable insights for future artificial intelligence and deep learning applications in this field., Translational Relevance: The methodology described herein can easily be applied in different clinical settings and may enlighten the beneficial effects of vitrectomy in several retinal vascular diseases.

Silicone oil is used as endotamponade following vitreoretinal surgery to maintain the retina reattached when indicated. This study investigates the hypothesis that silicone oil causes insulation effects on the retina by affecting its response to light. Electrophysiological responses to a flash stimulus were recorded using full-field electroretinography (ERG) and visual evoked potentials (VEP). Recordings were performed in 9 patients who underwent surgery for retinal detachment, before (1–2 days) and after (2–3 weeks) silicone oil removal (SOR) in both the study and the control eye. Flash ERG and VEP recordings were performed according to the ISCEV standard protocol. Statistically significant differences were found in the study eye in the amplitudes of the ERG responses and their corresponding ratios, i.e. the amplitude after SOR over the amplitude before SOR, in all conditions tested. No differences were observed in the control eye. The mean ratio of photopic ERG response was 3.4 ± 2.4 for the study and 1.0 ± 0.3 for the control eye (p <0.001). The mean ratio of ERG flicker response was 3.1 ± 2.4 and 1.0 ± 0.3, respectively (p = 0.003). Scotopic flash ERG ratio was 5.0 ± 4.4 for the study and 1.3 ± 0.6 for the control eye (p = 0.012). No differences were observed for the amplitude and latency of flash VEP response after SOR. Silicone oil causes a reduction in flash ERG responses; no effect was found on flash VEP responses. ERGs in eyes filled with silicone oil should not be considered representative of retinal functionality, in contrast to VEPs, which are not affected by silicone oil presence. [ABSTRACT FROM AUTHOR]

Subretinal injection (SI) is a novel drug delivery method, directly to retina for treatment of various eye disease. However, manual injection requires surgical experience and precision due to physiological factors. Robots offer solution to this issue, by reducing hand tremor and increased accuracy. This systematic review analyzes current status on robot-assisted SI compared to conventional techniques. Systematic search across 5 databases was conducted to identify studies comparing manual and robot-assisted SI procedures. Extracted data included robotic systems, complications, and success rates. Four studies, including one human trial, two ex vivo porcine eye studies, and one artificial eye model study were included in the synthesis. The findings show early advantages of robot-assisted SI. Compared to traditional interventions, robot procedures result in reduced tremor, what potentially lowers the risk of complications, including retinal tears and reflux. The first in-human randomized trial showed encouraging results, with no significant differences in surgical times or complications between robot-assisted and manual SI. However, major limitation of robot-assisted procedures is longer procedure time. Robot-assisted SI holds promise by offering increased precision and stability, reducing human error and potentially improving clinical outcomes. Challenges include cost, availability, and learning curve. Overall, early stage of robot-assisted SI suggests advantages in precision, complication reduction, and potentially improved drug delivery. Further research in human randomized trials is needed to fully assess its full-scale clinical application., (© 2024. The Author(s).)

Background: A 7-year-old male child was brought by his parents with a complaint of low vision in both eyes for 2 months. The child had low vision in both the eyes for 1.5 years, but the parents noticed when it worsened further 2 months back, leading to profound vision loss. On ophthalmic evaluation, the child did not perceive light in the right eye. Furthermore, anterior segment examination showed complicated cataract and open funnel retinal detachment with intra-retinal cysts in ultrasound (USG) B scan. In the left eye, he could appreciate light but with poor fixation. Fundus evaluation of the left eye showed total retinal detachment on indirect ophthalmoscopy, which was confirmed on USG B scan. Since the right eye had poor visual potential, no intervention was done. The left eye underwent pars plana vitrectomy with silicone oil tamponade, which led to successful anatomical outcomes. The immediate and late postoperative periods were uneventful, and the child was kept under follow-up and was observed closely., Purpose: To educate regarding the surgical management of giant retinal tears in a pediatric patient., Synopsis: To inform regarding the surgical challenges faced and steps adopted to manage such cases., Highlights: Through this case, we want to highlight the challenges faced, such as delayed presentation, difficult preoperative evaluation, intraoperative difficulties such as mobile retina, absence of posterior vitreous detachment, and tenacious vitreous gel. We also want to emphasize on the steps taken to overcome the challenges., Conclusion: In such challenging situations, effective planning, careful manipulation, and persistence are essential for success., Video Link: https://youtu.be/T0Gy6Wj13zI., (Copyright © 2024 Copyright: © 2024 Indian Journal of Ophthalmology.)

Clinical Relevance: Primary retinectomy in eyes not previously vitrectomized has been previously rarely performed in a minority of cases, unlike non-primary retinectomies in vitrectomized eyes., Background: This paper aims to determine anatomical and functional outcomes of primary retinectomy, and to assess structural macular changes among successful cases., Methods: In this retrospective multicentre cohort-study, 35 primary retinectomies in eyes undergoing initial vitrectomy for rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy C or D between 2014 and 2021 were included. The mean follow-up duration was 48 ± 59.24 months among successes and 46.54 ± 20.99 months among unsuccesses (p = 0.483)., Results: The anatomical success rate was 48.5% after one retinectomy and 60% after two retinectomies. Mean postoperative best corrected visual acuity (BCVA) was 1.85 ± 0.62 logMAR (6/425 Snellen equivalent). The difference from mean preoperative BCVA was not significant (p = 0.312). Final BCVA ≥ 6/60 was achieved in 17% of cases, and no cases gained ≥6/24. Final mean postoperative BCVA of successes was 1.69 ± 0.60 logMAR (6/294 Snellen equivalent) compared with 2.10 ± 0.57 logMAR (6/756 Snellen equivalent) of unsuccessful cases (p = 0.101). Post-operative macular optical coherence tomography was obtained from 95% of successes. Normal macular profile was found in 10% of cases, and the other cases demonstrated exudative maculopathy (60%), tractional maculopathy (20%) and macular atrophy (10%). Final BCVA was significantly higher in eyes with normal macular status compared to eyes with exudative maculopathy (p = 0.045) and macular atrophy (p = 0.025)., Conclusion: Primary retinectomy may be used for rhegmatogenous retinal detachment complicated with advanced proliferative vitreoretinopathy. Anatomical and functional outcome were inferior than non-primary retinectomies for grade C proliferative vitreoretinopathy. Functional outcome was influenced by macular status. Positive prognostic factors include final anatomical success and normal final macular anatomy.

The aim of this study was to introduce novel vector field analysis for the quantitative measurement of retinal displacement after epiretinal membrane (ERM) removal. We developed a novel framework to measure retinal displacement from retinal fundus images as follows: (1) rigid registration of preoperative retinal fundus images in reference to postoperative retinal fundus images, (2) extraction of retinal vessel segmentation masks from these retinal fundus images, (3) non-rigid registration of preoperative vessel masks in reference to postoperative vessel masks, and (4) calculation of the transformation matrix required for non-rigid registration for each pixel. These pixel-wise vector field results were summarized according to predefined 24 sectors after standardization. We applied this framework to 20 patients who underwent ERM removal to obtain their retinal displacement vector fields between retinal fundus images taken preoperatively and at postoperative 1, 4, 10, and 22 months. The mean direction of displacement vectors was in the nasal direction. The mean standardized magnitudes of retinal displacement between preoperative and postoperative 1 month, postoperative 1 and 4, 4 and 10, and 10 and 22 months were 38.6, 14.9, 7.6, and 5.4, respectively. In conclusion, the proposed method provides a computerized, reproducible, and scalable way to analyze structural changes in the retina with a powerful visualization tool. Retinal structural changes were mostly concentrated in the early postoperative period and tended to move nasally., (© 2024. The Author(s).)

Purpose: Subdamaging thermal retinal laser therapy has the potential to induce regenerative stimuli in retinal diseases, but validated dosimetry is missing. Real-time optoacoustic temperature determination and control could close this gap. This study investigates a first in vivo application., Methods: Two iterations of a control module that were optically coupled in between a continuous-wave commercial laser source and a commercial slit lamp were evaluated on chinchilla rabbits. The module allows extraction of the temperature rise in real time and can control the power of the therapy laser such that a predefined temperature rise at the retina is quickly achieved and held constant. Irradiations with aim temperatures from 45°C to 69°C were performed on a diameter of 200 µm and a heating time of 100 ms., Results: We analyzed 424 temperature-guided irradiations in nine eyes of five rabbits. The mean difference between the measured and aim temperature was -0.04°C ± 0.98°C. The following ED50 values for visibility thresholds could be determined: 58.6°C for funduscopic visibility, 57.7°C for fluorescein angiography, and 57.0°C for OCT. In all measurements, the correlation of tissue effect was higher to the temperature than to the average heating laser power used., Conclusions: The system was able to reliably perform temperature-guided irradiations, which allowed for better tissue effect control than simple power control. This approach could enhance the accuracy, safety, and reproducibility of thermal stimulating laser therapy., Translational Relevance: This study is a bridge between preclinical ex vivo experiments and a pilot clinical study.

Competing Interests: The authors declare that they have no conflict of interest.

The main objective of the present study is to use graphene as electrode neural interface material to design novel microelectrodes topology for retinal prosthesis and investigate device operation safety based on the computational framework. The study's first part establishes the electrode material selection based on electrochemical impedance and the equivalent circuit model. The second part of the study is modeling at the microelectrode-tissue level to investigate the potential distribution, generated resistive heat dissipation, and thermally induced stress in the tissue due to electrical stimulation. The formulation of Joule heating and thermal expansion between microelectrode-tissue-interface employing finite element method modeling is based on the three coupled equations, specifically Ohm's law, Navier's equation, and Fourier equation. Electrochemical simulation results of electrode material reveal that single-layer and few-layer graphene-based microelectrode has a specific impedance in the range of 0.02- [Formula: see text], comparable to platinum counterparts. The microelectrode of [Formula: see text] size can stimulate retinal tissue with a threshold current in the range of 8.7- [Formula: see text]. Such stimulation with the observed microelectrode size indicates that both microelectrodes and retinal tissue stay structurally intact, and the device is thermally and mechanically stable, functioning within the safety limit. The results reveal the viability of high-density graphene-based microelectrodes for improved interface as stimulating electrodes to acquire higher visual acuity. Furthermore, the novel microelectrodes design configuration in the honeycomb pattern gives the retinal tissue non-invasive heating and minimal stress upon electrical stimulation. Thus, it paves the path to designing a graphene-based microelectrode array for retinal prosthesis for further in vitro or in vivo studies.

Understanding the molecular composition of pathogenic tissues is a critical step in understanding the pathophysiology of disease and designing therapeutics. First described in 2009, single cell RNA sequencing (scRNAseq) is a methodology whereby thousands of cells are simultaneously isolated into individual micro-environments that can be altered experimentally and the genome-wide RNA expression of each cell is captured. It has undergone significant technological improvement over the last decade and gained tremendous popularity. scRNAseq is an improvement over prior pooled RNA analyses which cannot identify the cellular composition and heterogeneity of a tissue of interest. This new approach offers new opportunity for new discovery, as tissue samples can now be sub-categorized into groups of cell types based on genome-wide gene expression in an unbiased fashion. As ophthalmologists, we are uniquely positioned to obtain pathologic samples from the eye for further study. ScRNAseq has already been applied in ophthalmology to characterize retinal tissue, and it may offer the key to understanding various pathological processes in the future. [ABSTRACT FROM AUTHOR]

This Quasi Experimental study was conducted at Major Eye Clinic, Gujranwala, from January to December 2022, to study the effect of muting the sound of Argon Laser machine on patient compliance and the pain felt during pan-retinal photocoagulation (PRP). Eighty patients were included in the study with proliferative diabetic retinopathy (PDR), retinal breaks, lattice and myopic fundus degenerations for which PRP was performed. A total of 80 patients were enrolled, who were divided in two groups with 40 patients in each group. Group A patients received muted machine settings, while group B underwent regular PRP. The mean age was 54.6±3.4 years. Sixty-eight (85%) cases were of PDR, 4 (5%) of retinal breaks, 3 (3.75%) of lattice degenerations associated with breaks, and 5 (6.25%) of laser barrage. In group A, 28 (70%) patients had grade 1 and grade 2 pain score, while in group B, 26 (65%) had grade 3 and grade 4 pain score. It was concluded that by eliminating machine sound, noise anxiety can be greatly reduced ensuring better patient cooperation.

Even after idiopathic macular hole (MH) surgery and with successful closure of MH, aniseikonia is a common postoperative symptom. We investigated the correlation of MH diameter, retinal displacement and retinal layer thicknesses with aniseikonia in 41 eyes of 41 patients undergoing MH surgery with internal limiting membrane peeling. Aniseikonia was measured with the New Aniseikonia Test. Retinal displacement (RD%) was defined as change of retinal distance between the temporal margin of the optic papilla and the intersection of the retinal vessels. Changes of thicknesses of the inner nuclear layer (INL%) and the outer retinal layer (OR%) were calculated. Aniseikonia improved postoperatively. Preoperative aniseikonia and their improvement at 6 months correlated with MH diameters (P = 0.004-0.046). Improvement of aniseikonia correlated with temporal RD% (P = 0.002-0.012). Improvement of vertical aniseikonia correlated with INL% at 2 weeks and with the nasal OR% at 1, 3, and 6 months (P = < 0.001-0.028). MH diameter and age were significant predictors for improvement of aniseikonia. The greater the temporal retina displacement, and the thinner the postoperative INL and OR, the greater the improvement of aniseikonia. MH diameter and age are strong predictors for improvement of aniseikonia after MH surgery., (© 2024. The Author(s).)

Aim: The aim of the study is to retrospectively evaluate the anatomical success rate and functional results of 25G+ PPV in the treatment of newly diagnosed rhegmatogenous retinal detachment (RRD)., Material and Methods: The set consists of 152 eyes of 152 patients, of which 71 (47%) were men, average age 54 years, operated on by one surgeon for RRD at the Eye Clinic of the University Hospital and Medical Faculty of Masaryk University Brno from 1.7.2019 to 4.5.2021 using the 25G+ PPV technique. 25G+ PPV with pre-equatorial cerclage was performed on 7 patients. The patients' anamnesis included blunt ocular trauma and uncomplicated cataract surgery with implantation of a posterior chamber intraocular lens. The cause of RRD was retinal tear/s, regardless of their number and location. The transparency of the anterior segment of the eye enabled reliable visualization of the posterior segment. Preoperative proliferative vitreoretinopathy (PVR) grade A-D2 was admissible. Patients with a history of penetrating ocular trauma were excluded. The postoperative findings and functional outcomes of the patients were evaluated 1-3 months after PPV. The operation was anatomically successful if the retina was fully attached. Final visual acuity (VA) was evaluated for each patient. The final visual acuity examination was carried out typically on a Snellen optotype, either without correction, with the patient's own spectacle correction or with correction according to the current values on the autorefractometer. The arithmetic average was used for the numerical expression of the attained results, and the numerical values were also expressed in percentages. Since the different groups were not compared with each other, no statistical test was necessary to analyze the results., Results: In 150 (98.7%) of the 152 patients in the group, we achieved complete retinal reattachment, in 2 (1.3%) patients the retina remained detached, and we recorded anatomical failure of the treatment. Fifty (33%) patients achieved VA ≥ 4/8., Conclusion: In 133 (87.5%) patients, we are able to state anatomical success even without the presence of intraocular tamponade in the operated eye. These patients can be considered completely cured. 25G+ PPV has demonstrated its contribution to resolving RRD.

Background and Objective: Conventional (100 ms) pan-retinal photocoagulation (PRP) laser burns are larger than short-pulse (10 ms to 20 ms) PRP burns. This study investigates the effect of PRP burns of different sizes on retinal oxygenation., Method: A mathematical model using COMSOL Multiphysics 6 was used to create a three-dimensional abstraction of the coupled biology of the choroid, photoreceptor, and retinal tissues. Laser burn sizes were varied in the model, specifically considering burn diameters of 500 μm, 250 μm, and 125 μm, while keeping the total burn area constant., Results: Total increase in retinal oxygenation was the same for different burn sizes, but the oxygen distribution differed. Smaller burns resulted in a more even lateral oxygen distribution but with reduced penetration into the inner retina., Conclusions: Conventional and short-pulse PRP may affect retinal oxygenation differently, even when total burn area is the same. Further investigation into optimum burn size and pattern is required. [ Ophthalmic Surg Lasers Imaging Retina 2024;55:40-45.] .

Purpose: Various surgical techniques have been described for managing persistent macular holes after an unsuccessful vitrectomy with internal limiting membrane (ILM) peeling. However, the closure and functional improvement rates after these procedures are limited. Therefore, the aim of this study was to evaluate the usefulness of radial retinal incisions (retinotomies) in eyes with persistent large macula holes despite previous vitrectomy with ILM peeling., Design: In a retrospective case series, closure rate and best-corrected visual acuity (BCVA) were evaluated in eyes with persistent macular holes after an unsuccessful vitrectomy that included posterior vitreous detachment and ILM peeling., Subjects: 22 eyes of 22 patients (10 men and 12 women) underwent re-vitrectomy with radial retinal incisions. All the patients had undergone an unsuccessful surgery before., Methods: Small-incision re-vitrectomy with radial retinal incisions (retinotomies) and air tamponade was performed., Main Outcome Measurements: For all eyes, high-definition SD-OCT scans (SD-OCT Spectralis, Heidelberg Engineering GmbH, Germany) of the macula were routinely performed before surgery; 1 week and 1 month after surgery; and at final follow-up. Additionally, age, gender, axial length, macular hole diameter, biomicroscopic fundus evaluation and best-corrected visual acuity (BCVA) in logMAR and Snellen at baseline, 1 and 4 months after operation, and at the final follow-up visit were analyzed., Results: The mean baseline macular hole diameter was 668.5 ± 226.8 μm. At the final examination, 16 (72.72%) of the 22 macula holes were closed. Visual acuity increased in 17 eyes, was stable in 3 eyes, and decreased in 2 eyes owing to central retinal atrophy in both. The mean BCVA increased from logMAR 1.04 ± 0.29 at baseline to 0.57 ± 0.31 (Snellen 0.11 ± 0.05 to 0.33 ± 0.18). In all successful cases, macula hole closure was attained after 3 days, and none of the eyes showed macula hole recurrence., Conclusion: The results of this limited case series suggest that radial retinal incisions of the rim in persistent macula holes after initial surgery with ILM peeling increase the success rate of macula hole closure and results in a relevant increase in BCVA. However, as the number of eyes included in this series is limited, the results must be confirmed in a study with a larger sample size., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Almost one-fifth of patients undergoing surgery for sellar/supra-sellar tumors do not gain a significant improvement in their vision. Various methods have been described to predict prospective visual outcomes in them, although they lack uniformity., Objective: The study was conducted to predict visual outcomes following surgery for sellar and supra-sellar tumors compressing the anterior optic pathway based on pre-operative optical coherence tomography (OCT) parameters., Methods and Materials: This was a record-based observational descriptive longitudinal study done in a tertiary care center in India. Thirty-seven patients (74 eyes) diagnosed with sellar supra-sellar lesions were included in the study. Patients' ophthalmic evaluations, done pre-operatively and 3 months post-operatively, were reviewed. Spectral-domain OCT and segmentation were done using the automated segmentation technology of Spectralis software. The thickness of the respective layers was measured., Results and Conclusions: The mean age of the study population was 42.68 years. Eyes with a pre-operative visual acuity component of VIS (visual impairment score) ≤61, pre-operative ganglion cell layer thickness ≥26.31 um, a pre-operative inner plexiform layer thickness of ≥25.69 um, a pre-operative ganglion cell inner plexiform layer thickness of 52.00 um, pre-operative ganglion cell complex thickness ≥84.47 μm, and a pre-operative inner retinal layer thickness of ≥205.25 μm were more likely to have an improved visual outcome. Eyes with a pre-operative duration of visual symptoms of ≥15 months, VIS ≥126.50, a pre-operative decimal visual acuity of <0.035, a pre-operative visual field index of ≤8%, a pre-operative macular thickness of ≤287.06 um, a pre-operative macular RNFL (retinal nerve fiber layer) thickness ≤66.00 μm, and a pre-operative peri-papillary RNFL thickness ≤64.62 μm were unlikely to have visual improvement., (Copyright © 2024 Copyright: © 2024 Neurology India, Neurological Society of India.)

Background: Idiopathic epiretinal membrane (iERM) is a common disorder of the vitreomacular interface characterized by decreased visual acuity and metamorphopsia. This study aimed to analyze the association between the anatomical change of the retina and functional outcomes in iERM patients so as to derive the prognostic factors of visual acuity (VA) and metamorphopsia., Methods: Forty-five patients (one eye per patient; 45 eyes in total) who underwent pars plana vitrectomy and membrane peeling for iERM by a single surgeon were enrolled in this retrospective study. The results on best-corrected visual acuity (BCVA) and metamorphopsia as well as retinal images were obtained before the surgery and 1, 3, 6 months after the surgery. The BCVA and retinal microstructure, including central retinal thickness (CRT), ganglion cell layer (GCL) thickness, inner nuclear layer (INL) and outer nuclear layer + outer plexiform layer (ONL+OPL), and continuity of photoreceptor inner/outer segment (IS/OS) junction before and after iERM surgery were compared using paired samples t -test (continuous variables) or Chi-square test (categorical variables). Multiple regression analysis was carried out to explore the association among BCVA, M-score, and the parameters derived from optical coherence tomography., Results: Compared with preoperative data, a significant improvement in BCVA was observed 1, 3, and 6 months postoperatively (t = 5.37, p < 0.0001; t = 7.29, p < 0.0001; t = 6.44, p < 0.0001 for 1, 3, and 6 months postoperatively, respectively), whereas the M-score only decreased significantly 3 and 6 months after the surgery (t = 2.36, p = 0.02; t = 5.00, p < 0.0001, respectively). In comparison with the baseline, the CRT, INL, and ONL+OPL thickness showed a significant decrease at each postoperative follow-up time, and GCL thickness (t = 3.86, p = 0.0002) and IS/OS disruption ratio (χ 2 = 4.86, p = 0.027) were markedly reduced only 6 months postoperatively. Six-month postoperative BCVA was considerably associated with preoperative CRT and ONL+OPL thickness, as well as postoperative CRT, ONL+OPL thickness, and severity of IS/OS disruption. Moreover, the M-score after surgery was markedly correlated with both the preoperative and postoperative INL and CRT thickness., Conclusions: Both VA and M-score in iERM patients were significantly improved after vitrectomy. Pre- and post-operative CRT was significantly associated with both postoperative BCVA and M-score. Besides, pre- and post-operative INL thickness was correlated to postoperative metamorphopsia, and postoperative BCVA was associated with postoperative ONL+OPL thickness and IS/OS integrity.

Michael T. Trese, MD (1946-2022), a vitreoretinal surgeon, made significant contributions to the field of retina. Although most known for his work in pediatric retina surgery, he was a pioneer in areas such as medical retina, translational research, and telemedicine. This article reviews his major contributions to spread his knowledge more widely to vitreoretinal trainees and specialists. We discuss six areas where Trese made a lasting impact: lens-sparing vitrectomy, familial exudative vitreoretinopathy, congenital X-linked retinoschisis, autologous plasmin enzyme, regenerative medicine, and telemedicine. [ Ophthalmic Surg Lasers Imaging Retina 2023;54:701-712.] .

Purpose: To report the outcomes of the Peeling and Internal Limiting Membrane Reposition (PAIR) technique in myopic foveoschisis., Methods: A retrospective case series of eyes with myopic foveoschisis that underwent vitrectomy and PAIR. Visual acuity, fundus photographs, and optical coherence tomography measurements were obtained and analyzed. Data are presented as medians (ranges)., Results: A total of seven eyes underwent PAIR and were followed up for 339 days (188-436 days). No intraoperative complications were noted. One eye exhibited postoperative macular hole formation, but the hole was healed through fluid-gas exchange. At the last follow-up, the visual acuity had improved from 20/66 (20/332-20/40) to 20/40 (20/100-20/25), and the central foveal thickness had decreased from 576 µ m to 269 µ m. A repositioned internal limiting membrane (ILM) was observed in six of the eyes, and inner retinal dimples were noted in only two eyes. However, retinal wrinkles under the repositioned or perifoveal ILM were noted in five eyes., Conclusion: The PAIR technique relieved traction, restored the ILM, and achieved functional and morphological improvement in eyes with myopic foveoschisis. Limited occurrence of inner retinal dimples and retinal thinning was noted, but retinal wrinkles occurred, likely due to ILM contracture.

This protocol describes how to obtain high-quality retinal cryosections in larger animals, such as rabbits. After enucleation, the eye is briefly immersed in the fixative. Then, the cornea and iris are removed and the eye is left overnight for additional fixation at 4 °C. Following fixation, the lens is removed. The eye is then placed in a cryomold and filled with an embedding medium. By removing the lens, the embedding medium has better access to the vitreous and leads to better retinal stability. Importantly, the eye should be incubated in embedding medium overnight to allow complete infiltration throughout the vitreous. Following overnight incubation, the eye is frozen on dry ice and sectioned. Whole retinal sections may be obtained for use in immunohistochemistry. Standard staining protocols may be utilized to study the localization of antigens within the retinal tissue. Adherence to this protocol results in high-quality retinal cryosections that may be used in any experiment utilizing immunohistochemistry.

To generate and evaluate synthesized postoperative OCT images of epiretinal membrane (ERM) based on preoperative OCT images using deep learning methodology. This study included a total 500 pairs of preoperative and postoperative optical coherence tomography (OCT) images for training a neural network. 60 preoperative OCT images were used to test the neural networks performance, and the corresponding postoperative OCT images were used to evaluate the synthesized images in terms of structural similarity index measure (SSIM). The SSIM was used to quantify how similar the synthesized postoperative OCT image was to the actual postoperative OCT image. The Pix2Pix GAN model was used to generate synthesized postoperative OCT images. Total 60 synthesized OCT images were generated with training values at 800 epochs. The mean SSIM of synthesized postoperative OCT to the actual postoperative OCT was 0.913. Pix2Pix GAN model has a possibility to generate predictive postoperative OCT images following ERM removal surgery., (© 2023. The Author(s).)

Purpose: To assess the characteristics of completed panretinal photocoagulation (PRP), using ultra-widefield imaging in proliferative diabetic retinopathy., Methods: Quantitative assessment of ultra-widefield imaging images of 133 patients with proliferative diabetic retinopathy with completed PRP was made using ImageJ software. The parameters assessed included distance of laser spots from the optic disk, foveal center, superior and inferior arcades, and extent of the maximum width of laser. Areas assessed were total area of the image, area of the inner limit within which laser spots are restricted, minimum areas of unlasered patches, total area lasered, and ideal area to be covered by PRP., Results: Two hundred one images were assessed for the final analysis. The mean distance of laser spots was 4.2 ± 2.4 mm from the optic disk (nasal) and 6.6 ± 2.5 mm from the foveal center (temporal). The mean distance of laser spots from the superior arcade vessel was 3.2 ± 1.9 mm and 6.2 ± 4.4 mm from the inferior arcade. The mean area of the retina that should have been ideally lasered was found to be 900 ± 267 mm 2 , and the actual area lasered was found to be 681 ± 254.4 mm 2 ., Conclusion: Approximately one-quarter area of the retina continues to remain ischemic because of the lack of inadequate coverage of PRP. Further longitudinal studies are recommended, using ultra-widefield imaging to objectively assess the adequacy of PRP and its role in modulating the course of progression of the retinopathy.

Retinotomy refers to "cutting" or "incising" the retina, whereas retinectomy denotes "excising" the retina. Retinotomies and retinectomies aid in tackling traction and retinal shortening that persist following membrane dissection and scleral buckling. We performed a literature search using Google Scholar and PubMed, followed by a review of the references procured. All relevant literature was studied in detail and summarized. We discuss the indications of retinotomies and retinectomies for relaxing retinal stiffness, accessing the subretinal space for choroidal neovascular membrane, hemorrhage and abscess clearance, drainage retinotomies to allow retinal flattening, radial retinotomies to release circumferential traction, harvesting free retinal grafts, and prophylactic chorioretinectomies in trauma., Competing Interests: Declaration of Competing Interest Hung-Da Chou is a consultant for Novartis, Bayer, AbbVie, and Viatris. Sengul Ozdek is a consultant for Roche, Bayer, Novartis, and AbbVie. Andrew Chang is a consultant for Alcon, Novartis, Bayer, Hoffman La Roche, Apellis, and Allergan. Paisan Ruamviboonsuk is a consultant for Roche and Bayer. Rest of the authors report no disclosures., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Purpose: To describe the use of the amniotic membrane for the repair of the exit wound of a perforating injury involving the retina and the choroid., Methods: Case report., Results: A 46-year-old man presented one day after a perforating ocular injury with an exit wound close to the inferior temporal retinal vascular arcade. The next day, the patient underwent a combined vitrectomy and phacoemulsification with intraocular lens implantation. During vitrectomy, a retinochoroidectomy was performed at the exit wound and the internal limiting membrane was peeled over the macula and up to the exit wound. Laser retinopexy was followed by plugging of a piece of the amniotic membrane to the exit wound. A second piece of the amniotic membrane was used to cover the bare retinochoroidectomy area. The surgery was concluded with a silicone exchange. Postoperatively, no sign of proliferative vitreoretinopathy was observed, and at 3 months, the silicone oil was removed. The follow-up was uneventful, and the eye achieved a final visual acuity of 20/30., Conclusion: The amniotic membrane may offer a simple and safe solution for the repair of the exit wounds of perforating injuries involving the retina and the choroid. The use of the amniotic membrane for this purpose may afford the opportunity for early vitrectomy in the management of perforating ocular injuries., Competing Interests: The author does not have any proprietary interest or any commercial association that might pose a conflict of interest in connection with the submitted article.

Macular hole is a full-thickness neuroretinal defect in the fovea. The surgical solution is the removal of the internal limiting membrane (ILM) during vitrectomy with gas filling. Several surgical techniques have been described for the closure of refractory macular holes (about 5%), that reappear after successful surgery or do not close despite surgery. This article presents the first autologous neurosensory retina transplantation performed in Hungary for a large, refractory, full-thickness macular hole, with a brief overview of macular hole surgery. In September 2022, we performed a combined phacovitrectomy with ERM/ILM peeling and SF6 gas filling due to cataract, epiretinal membrane (ERM), and large macular hole due to the deterioration of vision in our patient's left eye for months, with a visual acuity of 6%. We drew the patient's attention to the importance of postoperative head positioning, which she ignored. With a visual acuity of 4%, due to a refractive macular hole (at the base: 983 μm, at the smallest diameter: 609 μm), on December 14, 2022, autologous neurosensory retina transplantation was performed using intraoperative OCT (Zeiss ARTEVO 800). At the end of the surgery, decalin was left in the eye to keep the graft in place, and the patient spent 5 days in a supine position. The decalin was removed with another operation, followed by C3F8 gas filling. 8 weeks after surgery, we documented a closed macular hole with 20% visual acuity, which was stable during the 6-month follow-up. Among the options considered for the resolution of refractory macular holes, autologous neurosensory retinal transplantation, which results in a visual improvement of our patient, is an intervention worth considering. Intraoperative OCT was a great help in performing the surgery. Although the decalin left temporarily in the eye helps to keep the transplant in place, it requires a continuous supine position and another operation is essential to remove it. Further experience is needed to establish the exact indication for autologous neurosensory retinal transplantation. Orv Hetil. 2023; 164(38): 1511-1517.

Purpose: To report a case of proliferative vitreoretinopathy (PVR) in a man with recurrent retinal detachment successfully managed without surgical intervention following the initiation of intravitreal methotrexate injections to arrest progression of PVR., Methods: Report of a case., Results: A 60-year-old man presented to the retina clinic 4 weeks after undergoing vitrectomy for rhegmatogenous retinal detachment and was found to have an inferior recurrent retinal detachment. He underwent repeat vitrectomy and scleral buckling with successful reattachment of the retina in the immediate postoperative period. At postoperative Week 2, preretinal membranes were noted inferiorly with stretching of the causative retinal break and localized subretinal fluid, consistent with early PVR. The patient underwent immediate laser barricade, and a course of intravitreal methotrexate injections was started. At the final follow-up 7 months later, the retina was fully attached without progression of PVR., Conclusion: Intravitreal methotrexate may play a role in arresting progression of early postoperative PVR and obviating the need for surgical intervention.

Purpose: To assess the risk of retinal displacement after scleral buckle (SB) versus pars plana vitrectomy with SB (PPV-SB)., Design: Multicenter prospective nonrandomized clinical trial., Methods: The study took place at VitreoRetinal Surgery in Minneapolis, Minnesota, Sankara Nethralaya in Chennai, India, and St. Michael's Hospital in Toronto, Canada from July 2019 to February 2022. Patients who underwent successful SB or PPV-SB for fovea-involving rhegmatogenous retinal detachment with gradable postoperative fundus autofluorescence (FAF) imaging were included in the final analysis. Two masked graders assessed FAF images 3 months postoperatively. Metamorphopsia and aniseikonia were assessed with M-CHARTs and the New Aniseikonia Test, respectively. The primary outcome was the proportion of patients with retinal displacement detected with retinal vessel printings on FAF in SB versus PPV-SB., Results: Ninety-one eyes were included in this study, of which 46.2% (42 of 91) had SB and 53.8% (49 of 91) underwent PPV-SB. Three months postoperatively, 16.7% (7 of 42) in the SB group and 38.8% (19 of 49) in the PPV-SB group had evidence of retinal displacement (difference = 22.1%; odds ratio = 3.2; 95% confidence interval [CI], 1.2-8.6; P = 0.02) on FAF. The statistical significance of this association increased after adjustment for extent of retinal detachment, baseline logarithm of the minimum angle of resolution, lens status, and sex in a multivariate regression analysis (P = 0.01). Retinal displacement was detected in 22.5% (6 of 27) of patients in the SB group with external subretinal fluid drainage and 6.7% (1 of 15) of patients without external drainage (difference = 15.8%; odds ratio = 4.0; 95% CI, 0.4-36.9; P = 0.19). Mean vertical metamorphopsia, horizontal metamorphopsia (MH), and aniseikonia were similar between patients in the SB and PPV-SB groups. There was a trend to worse MH in patients with retinal displacement versus those without retinal displacement (P = 0.067)., Conclusions: Scleral buckle is associated with less retinal displacement compared with PPV-SB, indicating that traditional PPV techniques cause retinal displacement. There is a trend toward increased risk of retinal displacement in SB eyes that underwent external drainage compared with SB eyes without drainage, which is consistent with our understanding that the iatrogenic movement of subretinal fluid, such as that which occurs intraoperatively during external drainage with SB, may induce retinal stretch and displacement if the retina is then fixed in the stretched position. There was a trend to worse MH at 3 months in patients with retinal displacement., Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article., (Copyright © 2023 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: The non-human primate (NHP) model is ideal for pre-clinical testing of novel therapies for human retinal diseases due to its similarity to the human visual system. However, intra-ocular delivery of gene therapy or cell transplantation to the retina gets hampered by the sticky vitreous body and poorly permeable inner limiting membrane (ILM) in primates. Although vitrectomy and ILM peeling are commonly performed in patients, many pitfalls exist in carrying out these procedures in the rhesus macaque, which have not been reported previously., Methods: We summarised common surgical pitfalls after performing vitrectomy and ILM peeling in four eyes of two rhesus macaques (one male and one female). We provided corresponding hands-on technical tips based on our surgical experience and literature search. Orbital CT scans were compared between adult rhesus macaques and humans. High-resolution surgical videos were recorded to demonstrate each critical surgical step., Results: Due to size difference, poor post-operative compliance, and high-standard requirements of a controlled experiment, there were eleven common surgical pitfalls during vitrectomy and ILM peeling in rhesus macaque. Falling into these pitfalls may produce discomfort, add fatigue, cause surgical complications, or even lead to the exclusion of the NHP from an experimental group., Conclusion: Recognition and circumvention of these pitfalls during vitrectomy and ILM peeling in NHP are essential. By focusing on these surgical pitfalls, we can better carry out preclinical tests of novel therapies for retinal diseases in the NHP model., (© 2022. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: To report the biological stability and postoperative outcomes of a second-generation, single-piece, flexible synthetic cornea in a rabbit model., Methods: Device materials and design were amended to enhance biointegration. Optic skirt design devices were made from compact perfluoroalkoxy alkane with porous expanded polytetrafluoroethylene ingrowth surface overlying the skirt and optic wall. Sixteen devices were implanted into intrastromal pocket in rabbit eyes. Rabbits were randomly assigned to 6- and 12-month follow-up cohorts (n = 8 in each) postoperatively. Monthly examinations and optical coherence tomography assessed cornea-device integration, iridocorneal angle, optic nerve, and retina., Results: There were no intraoperative complications. All devices were in situ at exit, with clear optics. No retroprosthetic membrane, glaucoma, cataract formation, or retinal detachment was observed. Two rabbits in the 6-month group had mild, focal anterior lamella thinning without retraction adjacent to the optic near tight sutures. Three postoperative complications occurred in the 12-month group. One rabbit diagnosed with endophthalmitis was euthanized on day 228. Mild sterile focal retraction of anterior lamella occurred in two rabbits, which were terminated on days 225 and 315. Light microscopic examination of enucleated globes demonstrated fibroplasia with new collagen deposition into the porous scaffold without significant inflammation, encapsulation, or granuloma formation., Conclusions: Clinical evaluations, imaging, and histopathological findings indicate favorable outcomes of this synthetic corneal device in a rabbit model. Early feasibility studies in humans are being planned., Translational Relevance: Favorable 12-month results of the device in rabbits demonstrate vision-restoring potential in corneally blind individuals at high risk of failure with donor keratoplasty.

During the final (third) trimester outside of the womb, the retina develops significantly and is vulnerable to problems. Similar to how the cerebral cortex does, the cerebellum also grows quickly during this time and is susceptible to upsetting environmental influences. The only factors that show promise for lowering the incidence and retinopathy of prematurity (ROP) severity among high-risk infants are prematurity prevention, preeclampsia control, and prudent use of oxygen therapy and ventilation. The third trimester is when the cerebral cortex, cerebellum, and retina develop. These areas are vulnerable to environmental influences if their development is interrupted. Throughout childhood and adolescence, neurodevelopmental defects have been linked to impaired cortical development and smaller brain volumes. Reduced cerebellar volumes have been linked to an increased risk of autism spectrum disorder, lower motor performance, impaired executive functioning, and poorer cognitive outcomes. The complete avascular retina, as well as the peripheral retina, should be treated during retinal ablation with laser photocoagulation (using a transpupillary diode, 11 argon, and three FD-YAG) or cryoablation as failing to do so promotes disease progression and results in unfavorable anatomical and refractive outcomes.

Purpose: To evaluate the functional and structural outcomes as well as postoperative complications after pars plana vitrectomy (PPV) for severe features of proliferative diabetic retinopathy (PDR) in type 1 and type 2 diabetes mellitus (DM) patients., Methods: Twenty two eyes of type 1 diabetics (DM1 group) and 27 eyes of type 2 diabetics (DM2 group) were included. Best corrected visual acuity (BCVA), intraocular pressure (IOP), postoperative structural changes in optical coherence tomography (OCT) and postoperative complications such as recurrent vitreous haemorrhage, diabetic macular oedema, secondary glaucoma and persistent tractional retinal detachment (TRD) were assessed and compared between the two groups., Results: Complete reattachment of retina was achieved in 88.9% from the DM1 group and in 95.5% from the DM2 group and remained attached in follow-up. BCVA in DM2 group was significantly lower preoperatively (p = 0.04). Mean postoperative BCVA significantly improved in both studied groups, but it was more evident in eyes of type 2 diabetics compared to type 1 diabetics. In eyes in the DM1 group there was perceptible stabilisation of BCVA. Poor visual acuity or lack of improvement in BCVA in the DM1 group was related to preoperative subretinal haemorrhage in macular region, and TRD involving macula, whereas in the DM2 group-to preoperative subretinal haemorrhage and neovascular glaucoma. The postoperative structural changes (disruption of EZ and ELM) were observed more often in DM2 group, but had the greatest impact on BCVA in eyes of type 1 DM. Complications after PPV for PDR were rare and hadn't a significant influence on the final functional outcomes in both groups., Conclusions: Functional improvement after PPV for severe features of proliferative diabetic retinopathy were more noticeable in patients with type 2 DM. Postoperative structural changes had more negative impact on BCVA in type 1 diabetics., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Kaźmierczak et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)