Background: Virtual reality, augmented reality, and mixed reality make use of a variety of different software and hardware, but they share three main characteristics: immersion, presence, and interaction. The umbrella term for technologies with these characteristics is extended reality. The ability of extended reality to create environments that are otherwise impossible in the real world has practical implications in the medical discipline. In ophthalmology, virtual reality simulators have become increasingly popular as tools for surgical education. Recent developments have also explored diagnostic and therapeutic uses in ophthalmology. Objective: This systematic review aims to identify and investigate the utility of extended reality in ophthalmic education, diagnostics, and therapeutics. Methods: A literature search was conducted using PubMed, Embase, and Cochrane Register of Controlled Trials. Publications from January 1, 1956 to April 15, 2020 were included. Inclusion criteria were studies evaluating the use of extended reality in ophthalmic education, diagnostics, and therapeutics. Eligible studies were evaluated using the Oxford Centre for Evidence-Based Medicine levels of evidence. Relevant studies were also evaluated using a validity framework. Findings and relevant data from the studies were extracted, evaluated, and compared to determine the utility of extended reality in ophthalmology. Results: We identified 12,490 unique records in our literature search; 87 met final eligibility criteria, comprising studies that evaluated the use of extended reality in education (n=54), diagnostics (n=5), and therapeutics (n=28). Of these, 79 studies (91%) achieved evidence levels in the range 2b to 4, indicating poor quality. Only 2 (9%) out of 22 relevant studies addressed all 5 sources of validity evidence. In education, we found that ophthalmic surgical simulators demonstrated efficacy and validity in improving surgical performance and reducing complication rates. Ophthalmoscopy simulators demonstrated efficacy and validity evidence in improving ophthalmoscopy skills in the clinical setting. In diagnostics, studies demonstrated proof-of-concept in presenting ocular imaging data on extended reality platforms and validity in assessing the function of patients with ophthalmic diseases. In therapeutics, heads-up surgical systems had similar complication rates, procedural success rates, and outcomes in comparison with conventional ophthalmic surgery. Conclusions: Extended reality has promising areas of application in ophthalmology, but additional high-quality comparative studies are needed to assess their roles among incumbent methods of ophthalmic education, diagnostics, and therapeutics.

Purpose: To determine 2-year efficacy of the PAUL Glaucoma Implant (PGI), a novel glaucoma tube shunt in patients with advanced glaucoma. Participants: Patients with glaucoma refractory to maximum medical therapy or previous failed glaucoma surgery. Methods: Retrospective review of all patients who had underwent PGI implantation in a single tertiary institution between May 1, 2017 and March 30, 2021. Main Outcome Measures: Primary outcome measure was failure defined as intraocular pressure (IOP) >18 mm Hg or <6 mm Hg on 2 consecutive visits after 3 months, reoperation for IOP-related indication, explantation of implant or loss of light perception vision. Complete success was defined as unmedicated IOP ≤18 mm Hg or ≥6 mm Hg in the absence of failure. Results: Forty-five eyes in 45 patients were identified, with mean follow-up duration of 24.9±2.0 months. Thirty patients (66.7%) had primary glaucoma and 11 (24.4%) with previous glaucoma surgery. At 2 years following surgery, 8 eyes (17.8%) fulfilled the failure criteria with 32 eyes (71.1%) achieving complete success. Compared with mean medicated preoperative IOP (19.8±6.3 mm Hg), postoperative IOP at 24 months was 13.9±3.7 (P<0.01). Mean number of medications decreased from 3.2±0.8 preoperatively to 0.29±0.65 at 24 months (P<0.01). Significant complications included self-limiting shallow anterior chamber (n=10; 22.2%), hypotony requiring intervention (n=4; 8.9%) and tube occlusion (n=4; 8.9%). Conclusions: The PGI was able to achieve sustained IOP reduction with reduction of medications at 2 years postsurgery in patients with advanced glaucoma.

Background/Aims Accurate isolation and quantification of intraocular dimensions in the anterior segment (AS) of the eye using optical coherence tomography (OCT) images is important in the diagnosis and treatment of many eye diseases, especially angle-closure glaucoma. Method In this study, we developed a deep convolutional neural network (DCNN) for the localisation of the scleral spur; moreover, we introduced an information-rich segmentation approach for this localisation problem. An ensemble of DCNNs for the segmentation of AS structures (iris, corneosclera shell adn anterior chamber) was developed. Based on the results of two previous processes, an algorithm to automatically quantify clinically important measurements were created. 200 images from 58 patients (100 eyes) were used for testing. Results With limited training data, the DCNN was able to detect the scleral spur on unseen anterior segment optical coherence tomography (ASOCT) images as accurately as an experienced ophthalmologist on the given test dataset and simultaneously isolated the AS structures with a Dice coefficient of 95.7%. We then automatically extracted eight clinically relevant ASOCT measurements and proposed an automated quality check process that asserts the reliability of these measurements. When combined with an OCT machine capable of imaging multiple radial sections, the algorithms can provide a more complete objective assessment. The total segmentation and measurement time for a single scan is less than 2 s. Conclusion This is an essential step towards providing a robust automated framework for reliable quantification of ASOCT scans, for applications in the diagnosis and management of angle-closure glaucoma.

Précis: In advanced refractory glaucoma which has failed prior MP3 laser, MP3 Plus is effective in reducing intraocular pressure (IOP) without significant complications. It is also useful as a temporizing procedure before incisional surgery. Purpose: To evaluate the efficacy and safety of MP3 Plus, a novel technique using modified micropulse transscleral cyclophototherapy (MPTCP) in eyes with refractory glaucoma or failed MPTCP treatment. Methods: This is a retrospective interventional case series. In total, 32 consecutive eyes from 29 patients with uncontrolled IOPs who had previous MPTCP or refractory glaucoma underwent MP3 Plus, a modified MPTCP where additional discrete pulses are applied. The main outcome measurement was IOP at 1, 3, 6, and 12 months postprocedure, with success defined as a 20% reduction in baseline IOP, an IOP of 25 mmHg or less, and no need for further reoperation. We collected and analyzed visual acuity, number of glaucoma medications, and complications. Results: The patients had an average of 1.4±0.9 glaucoma procedures before treatment, where 87.5% underwent one or more previous MPTCP with suboptimal response. Of the eyes presenting for follow-up, 51.6% (n=31), 37.0% (n=27), 35.7% (n=28), and 25.9% (n=27) achieved the primary outcome at 1, 3, 6, and 12 months, respectively. Baseline IOP was 33.7±11.6 mmHg (n=32 eyes) and posttreatment IOP at 1, 3, 6, and 12 months were 21.0±9.0 mmHg (n=31; P<0.0001), 26.2±10.8 mmHg (n=25; P<0.0001), 23.2±9.4 mmHg (n=20; P<0.05), and 24.6±9.8 mmHg (n=16; P<0.001), respectively. There was a reduction in glaucoma medications from 3.4±0.8 preoperatively to 2.8±1.2 (n=16; P<0.05) at 12 months. There were no cases of prolonged inflammation or hypotony. Conclusions: MP3 Plus is effective and safe in lowering IOP in eyes with refractory glaucoma after previous failed MPTCP.

Precis: Micropulse transscleral cyclophotocoagulation (MPTCP) is only moderately effective in lowering intraocular pressure (IOP) and is useful as an adjunct procedure to other glaucoma surgeries. There was a small risk of loss of vision, prolonged hypotony, and phthisis bulbi. Aim: The aim of this study was to determine the efficacy and safety of a single MPTCP treatment for an Asian population with advanced glaucoma. Methods: This is a retrospective single-center study of 207 eyes (207 patients) with advanced glaucoma which underwent first-time MPTCP between January 1, 2008, and March 31, 2018. Success was defined as IOP of 6 to 21 mm Hg or ≥20% reduction in IOP without an increase in glaucoma medication from baseline, and without glaucoma reoperation. The IOP, best-corrected visual acuity, and number of glaucoma medications were also analyzed. Results: The mean (SD) age was 64.9±16.9 years. The mean follow-up duration was 18.7±16.2 months. The rate of success at postoperative years 1 and 2 follow-up was 44.1% and 32.6%, respectively. The median survival time of MPTCP was 9.0 months and 85 (40.9%) eyes received reoperation. The mean IOP decreased from 31.5±12.0 mm Hg preoperatively to 22.1±10.3 and 23.8±11.8 mm Hg at postoperative years 1 and 2, respectively (P<0.0001). The mean number of glaucoma medications was reduced from 3.3±1.0 preoperatively to 2.6±1.1 and 2.4±1.1 at postoperative years 1 and 2, respectively (P50% failed by 1 year.

Precis: Repeat micropulse transscleral cyclophotocoagulation (MPTCP) has some benefit in lowering intraocular pressure (IOP). There was a small risk of loss of vision, prolonged hypotony, and phthisis bulbi. Aim: This study aimed to determine the efficacy and safety of repeated MPTCP for an Asian population with refractory glaucoma. Methods: This is a retrospective case series of 43 eyes (43 patients) with severe glaucoma which underwent repeated MPTCP. Baseline parameters were taken from the visit just before the second MPTCP session. Success was defined as IOP of 6 to 21 mm Hg or ≥20% reduction in IOP without an increase in glaucoma medication from baseline, without further glaucoma reoperation, and ≤3 total MPTCP episodes. The IOP, number of IOP-lowering medications, and best-corrected visual acuity were documented preoperatively and postoperatively. Postoperative complications were also analyzed. Results: The mean age±SD was 57.4±18.2 years with a mean follow-up duration of 28.9±27.5 months. Neovascular glaucoma was the most common type of glaucoma [18 eyes (41.9%)]. The success rates at postoperative years 1, 2, and 3, and the latest follow-up were 36.4%, 42.9%, 32.0%, and 39.5%, respectively. The median survival time of repeat MPTCP was 4.6 months. Compared with the preoperative mean IOP (35.2±11.0 mm Hg), the mean IOP at postoperative years 1, 2, and 3, and latest follow-up, was 27.8±13.7 mm Hg (P=0.004), 27.4±12.4 (P=0.003), 31.8±13.2 (P=0.35), and 27.1±13.8 mm Hg (P=0.002), respectively. The mean number of IOP-lowering medications was reduced from 3.3±0.9 preoperatively to 2.8±1.3 at the final follow-up (P=0.007). Postoperative complications included prolonged hypotony [3 eyes (7.0%)] and phthisis bulbi [2 eyes (4.7%)]. Conclusion: Repeated MPTCP is at best moderately effective in lowering IOP for eyes with advanced glaucoma.