Safety profile and surgical outcomes of early vitrectomy in eyes with unexplained fundus-obscuring vitreous haemorrhage.

OBJECTIVES: To investigate the safety profile and the surgical outcomes in a large cohort of subjects undergoing early vitrectomy for unexplained fundus-obscuring vitreous haemorrhage (FOVH). METHODS: Retrospective, single-centre case series of 186 consecutive eyes presenting between January 2018 and February 2020. Primary outcomes included change in best-corrected visual acuity (BCVA), rate of intra-operative retinal tears or retinal detachment (RD), baseline proliferative vitreoretinopathy (PVR), association of demographics with clinical outcomes, and rate of significant adverse events characterised by reoperation. RESULTS: Main final diagnosis was haemorrhagic posterior vitreous detachment (76%) and the overall risk of a retinal tear with or without RD found at the time of surgery was 69%. Vitrectomy was completed within 24 h in 94% of eyes. Rate of RD was 18%; all cases were macula-sparing with no PVR. Mean change in BCVA from baseline to final follow-up was -1.53 ± 0.69 LogMAR, p < 0.001. Time from presentation to surgery was significantly associated with final BCVA (p = 0.036, beta co-efficient 0.097). There was a significant association between presence of RD and age <60 y (OR 0.94, 95%CI [0.90-0.98], p = 0.003). 4.8% required repeated vitrectomy for post-operative RD (4), epiretinal membrane formation (3), removal of oil (1), and recurrent FOVH (1). None of these reoperations were induced by complications during the first surgery. CONCLUSION: There is a high rate of retinal breaks in cases with unexplained FOVH, and the risk of a concomitant RD is higher in younger subjects. Early vitrectomy within 24 h appears a safe first-line treatment and yields good clinical outcomes.

Intraoperative subconjunctival steroid reduces the incidence of pseudophakic macular oedema: a cohort study of 20,066 consecutive phacoemulsification surgeries.

BACKGROUND/OBJECTIVES: Pseudophakic macular oedema remains the most common sight-threatening complication following cataract surgery. This study aims to assess the effect of intraoperative subconjunctival steroids on the rate of pseudophakic cystoid macular oedema. METHODS: A retrospective, observational database study of 20 066 consecutive phacoemulsification surgeries. The incidence of pseudophakic cystoid macular oedema was compared in eyes that did and did not receive intraoperative subconjunctival steroid injection during routine cataract surgery. RESULTS: Intraoperative subconjunctival injection of dexamethasone or betamethasone sodium phosphate significantly reduced the odds of developing pseudophakic cystoid macular oedema across the cohort (odds ratio: 0.67; 95% confidence interval: 0.46-0.98, p = 0.039). The effect of subconjunctival steroids on pseudophakic macular oedema remained independently associated on multivariate logistic regression analysis (p = 0.028). CONCLUSION: This study demonstrates that administration of intraoperative subconjunctival steroid injection is associated with a reduced incidence of pseudophakic cystoid macular oedema in routine, uncomplicated cataract surgery.

Surgical biomicroscopy-guided intra-operative optical coherence tomography (iOCT) image super-resolution.

PURPOSE: Intra-retinal delivery of novel sight-restoring therapies will require the precision of robotic systems accompanied by excellent visualisation of retinal layers. Intra-operative Optical Coherence Tomography (iOCT) provides cross-sectional retinal images in real time but at the cost of image quality that is insufficient for intra-retinal therapy delivery.This paper proposes a super-resolution methodology that improves iOCT image quality leveraging spatiotemporal consistency of incoming iOCT video streams. METHODS: To overcome the absence of ground truth high-resolution (HR) images, we first generate HR iOCT images by fusing spatially aligned iOCT video frames. Then, we automatically assess the quality of the HR images on key retinal layers using a deep semantic segmentation model. Finally, we use image-to-image translation models (Pix2Pix and CycleGAN) to enhance the quality of LR images via quality transfer from the estimated HR domain. RESULTS: Our proposed methodology generates iOCT images of improved quality according to both full-reference and no-reference metrics. A qualitative study with expert clinicians also confirms the improvement in the delineation of pertinent layers and in the reduction of artefacts. Furthermore, our approach outperforms conventional denoising filters and the learning-based state-of-the-art. CONCLUSIONS: The results indicate that the learning-based methods using the estimated, through our pipeline, HR domain can be used to enhance the iOCT image quality. Therefore, the proposed method can computationally augment the capabilities of iOCT imaging helping this modality support the vitreoretinal surgical interventions of the future.

Deep iterative vessel segmentation in OCT angiography.

This paper addresses retinal vessel segmentation on optical coherence tomography angiography (OCT-A) images of the human retina. Our approach is motivated by the need for high precision image-guided delivery of regenerative therapies in vitreo-retinal surgery. OCT-A visualizes macular vasculature, the main landmark of the surgically targeted area, at a level of detail and spatial extent unattainable by other imaging modalities. Thus, automatic extraction of detailed vessel maps can ultimately inform surgical planning. We address the task of delineation of the Superficial Vascular Plexus in 2D Maximum Intensity Projections (MIP) of OCT-A using convolutional neural networks that iteratively refine the quality of the produced vessel segmentations. We demonstrate that the proposed approach compares favourably to alternative network baselines and graph-based methodologies through extensive experimental analysis, using data collected from 50 subjects, including both individuals that underwent surgery for structural macular abnormalities and healthy subjects. Additionally, we demonstrate generalization to 3D segmentation and narrower field-of-view OCT-A. In the future, the extracted vessel maps will be leveraged for surgical planning and semi-automated intraoperative navigation in vitreo-retinal surgery.

Learned optical flow for intra-operative tracking of the retinal fundus.

PURPOSE: Sustained delivery of regenerative retinal therapies by robotic systems requires intra-operative tracking of the retinal fundus. We propose a supervised deep convolutional neural network to densely predict semantic segmentation and optical flow of the retina as mutually supportive tasks, implicitly inpainting retinal flow information missing due to occlusion by surgical tools. METHODS: As manual annotation of optical flow is infeasible, we propose a flexible algorithm for generation of large synthetic training datasets on the basis of given intra-operative retinal images. We evaluate optical flow estimation by tracking a grid and sparsely annotated ground truth points on a benchmark of challenging real intra-operative clips obtained from an extensive internally acquired dataset encompassing representative vitreoretinal surgical cases. RESULTS: The U-Net-based network trained on the synthetic dataset is shown to generalise well to the benchmark of real surgical videos. When used to track retinal points of interest, our flow estimation outperforms variational baseline methods on clips containing tool motions which occlude the points of interest, as is routinely observed in intra-operatively recorded surgery videos. CONCLUSIONS: The results indicate that complex synthetic training datasets can be used to specifically guide optical flow estimation. Our proposed algorithm therefore lays the foundation for a robust system which can assist with intra-operative tracking of moving surgical targets even when occluded.

Phacoemulsification Combined With Endoscopic Versus Transscleral Cyclophotocoagulation in Poorly Controlled Glaucoma: A Comparative Case Series.

OBJECTIVE: The objective of this study was to report medium-term outcomes of a novel combination of phacoemulsification with transscleral cyclophotocoagulation (phaco-TCP) compared with combined phacoemulsification and endoscopic cyclophotocoagulation (phaco-ECP) in patients with uncontrolled or suboptimally controlled glaucoma and coexisting cataract. MATERIALS AND METHODS: Retrospective case series of 80 consecutive patients with a minimum of 12 months of follow-up. In total, 46 eyes underwent phaco-ECP and 34 phaco-TCP. Success was defined as intraocular pressure (IOP) between 6 and 21 mm Hg with ≥20% reduction from preoperative IOP (with no increase in ocular hypotensive medications or further glaucoma surgery). Secondary outcomes were change in IOP, number of ocular hypotensive medications and safety. RESULTS: The mean follow-up was 32.6 ±10.3 months. Preoperative clinical characteristics were similar in both groups. At latest follow-up, success rate was greater with phaco-TCP than phaco-ECP (67.6% and 47.8%, P=0.037). IOP was also significantly lower after phaco-TCP (14.88±5.57 mm Hg, from 22.62±6.52 mm Hg) than phaco-ECP (18.07±6.72 mm Hg, from 22.83±7.88, P=0.0273). Ocular hypotensive medications required reduced similarly after phaco-TCP (from 3.38±0.88 to 2.65±1.04 medications, P=0.0012) and phaco-ECP (from 3.07±0.929 to 2.63±1.42 medications, P=0.0108). There were no cases of hypotony or reduction in vision related to glaucoma with either surgical intervention and a similar proportion required further glaucoma surgery (phaco-ECP 15.2%, phako-TCP 5.9%, P=0.2884). CONCLUSIONS: Phaco-TCP appears more successful in controlling IOP than phaco-ECP with similar safety. Further investigation is warranted of this newly proposed combination which may be particularly useful where access or experience with ECP or other minimally invasive glaucoma surgery is limited.

Optic Disc Pit Maculopathy: New Perspectives on the Natural History.

PURPOSE: To investigate the natural history of optic disc pit maculopathy and explore the associations between demographic, anatomic, and functional characteristics. DESIGN: Retrospective, comparative case series. METHODS: This was a single-center medical record review of previously untreated optic disc pit maculopathy. Baseline data of visual function, demographics, and pit physiognomy were collected, and further subgroup analysis was undertaken on patients with long-term follow-up, according to whether they were monitored or received surgical intervention. LogMAR visual acuity was the primary outcome measure, and anatomic characteristics were reported where available. RESULTS: Eighty-seven patients were identified with a new presentation of optic disc pit maculopathy. No demographic or pit features were correlated with vision at baseline. In 51 patients with available optical coherence tomography data, only the presence of subretinal fluid at baseline was associated with poorer visual acuity (P < .001). Fifty-two patients who were monitored without treatment had available long-term follow-up data. The mean change in visual acuity in this group was 0.01, with 77% maintaining visual acuity ≤0.30. Twenty-seven patients underwent surgery and showed significant postoperative improvement in vision (P < .001), with 59% achieving an acuity ≤0.30. Duration of postoperative follow-up was associated with better visual acuity (P = .007). CONCLUSION: Many patients with optic disc pit maculopathy maintain good long-term visual acuity and may demonstrate resolution of subretinal fluid in the absence of surgical intervention. There may be evidence to support delaying surgical treatment until visual deterioration is observed because of the potential stability or spontaneous improvement of the condition, the high rate of reoperation, and the long-term positive outcomes of deferred intervention.

Orbital plasmablastic lymphoma.

Plasmablastic lymphoma is an unusual and aggressive form of diffuse large B-cell lymphoma, which arises more commonly within the oronasal mucosa. It should be considered as a differential diagnosis for rapidly growing periorbital lesions, particularly in the context of HIV positivity.

Phacoemulsification plus endoscopic cyclophotocoagulation versus phacoemulsification alone in primary open-angle glaucoma.

PURPOSE: To examine the efficacy and safety of combined phacoemulsification and endoscopic cyclophotocoagulation (phaco-ECP) compared to phacoemulsification alone in patients with primary open-angle glaucoma (POAG). METHODS: We performed a retrospective notes review of 99 consecutive clinical records of patients with POAG from 2 London eye departments. A total of 69 patients who underwent phaco-ECP and 30 sex- and age-matched control patients who underwent cataract surgery alone were included. Data on intraocular pressure (IOP), visual acuity (VA), number of ocular hypotensive medications, and postoperative complications were collected over 12 months. The primary outcome measure was defined as an IOP within normal limits (<21 mm Hg) and at least a 20% reduction in IOP from baseline. RESULTS: Mean IOP was significantly decreased in both groups after 1 year (p<0.001 from baseline). The success rate was significantly higher in the phaco-ECP group (69.6%) than in the phaco group (40%) after 1 year (p = 0.004). Reduction in mean IOP and number of medications was also greater in the phaco-ECP group after 1 year (IOP reduction: 4.5 ± 5.13 mm Hg vs 1.83 ± 3.61 mm Hg; p = 0.007; number of medications reduction: 0.73 ± 0.71 vs 0.23 ± 0.56; p = 0.001). Both groups achieved a similar improvement in VA. There was a higher incidence of minor and self-limiting complications in the phaco-ECP group (p<0.047). CONCLUSIONS: Phaco-ECP resulted in a greater reduction in IOP and number of medications than phacoemulsification alone in POAG.

The effects of absence of stereopsis on performance of a simulated surgical task in two-dimensional and three-dimensional viewing conditions.

BACKGROUND: Stereopsis is believed to be advantageous for surgical tasks that require precise hand-eye coordination. We investigated the effects of short-term and long-term absence of stereopsis on motor task performance in three-dimensional (3D) and two-dimensional (2D) viewing conditions. METHODS: 30 participants with normal stereopsis and 15 participants with absent stereopsis performed a simulated surgical task both in free space under direct vision (3D) and via a monitor (2D), with both eyes open and one eye covered in each condition. RESULTS: The stereo-normal group scored higher, on average, than the stereo-absent group with both eyes open under direct vision (p<0.001). Both groups performed comparably in monocular and binocular monitor viewing conditions (p=0.579). CONCLUSIONS: High-grade stereopsis confers an advantage when performing a fine motor task under direct vision. However, stereopsis does not appear advantageous to task performance under 2D viewing conditions, such as in video-assisted surgery.