Automated expert-level scleral spur detection and quantitative biometric analysis on the ANTERION anterior segment OCT system.

AIM: To perform an independent validation of deep learning (DL) algorithms for automated scleral spur detection and measurement of scleral spur-based biometric parameters in anterior segment optical coherence tomography (AS-OCT) images. METHODS: Patients receiving routine eye care underwent AS-OCT imaging using the ANTERION OCT system (Heidelberg Engineering, Heidelberg, Germany). Scleral spur locations were marked by three human graders (reference, expert and novice) and predicted using DL algorithms developed by Heidelberg Engineering that prioritise a false positive rate <4% (FPR4) or true positive rate >95% (TPR95). Performance of human graders and DL algorithms were evaluated based on agreement of scleral spur locations and biometric measurements with the reference grader. RESULTS: 1308 AS-OCT images were obtained from 117 participants. Median differences in scleral spur locations from reference locations were significantly smaller (p<0.001) for the FPR4 (52.6±48.6 µm) and TPR95 (55.5±50.6 µm) algorithms compared with the expert (61.1±65.7 µm) and novice (79.4±74.9 µm) graders. Intergrader reproducibility of biometric measurements was excellent overall for all four (intraclass correlation coefficient range 0.918-0.997). Intergrader reproducibility of the expert grader (0.567-0.965) and DL algorithms (0.746-0.979) exceeded that of the novice grader (0.146-0.929) for images with narrow angles defined by OCT measurement of angle opening distance 500 µm anterior to the scleral spur (AOD500)<150 µm. CONCLUSIONS: DL algorithms on the ANTERION approximate expert-level measurement of scleral spur-based biometric parameters in an independent patient population. These algorithms could enhance clinical utility of AS-OCT imaging, especially for evaluating patients with angle closure and performing intraocular lens calculations.

Steps to Measurement Floor of an Optical Microangiography Device in Glaucoma.

PURPOSE: To compare dynamic ranges and steps to measurement floors of peripapillary and macular metrics from a complex signal-based optical microangiography (OMAGC) optical coherence tomography angiography (OCTA) device for glaucoma with those of OCT measurements. DESIGN: Cross-sectional study. METHODS: Imaging of 252 eyes from 173 patients with glaucoma and 123 eyes from 92 subjects without glaucoma from a glaucoma clinic was quantified using custom and commercial software. Metrics from OCT (retinal nerve fiber layer [RNFL], ganglion cell/inner plexiform layer [GCIPL]) and OCTA (custom: peripapillary vessel area density [pVAD], macular vessel area density [mVAD], and macular vessel skeleton density [mVSD]; commercial: peripapillary perfusion density [pPDZ], macular perfusion density [mPDZ], and macular vessel density [mVDZ]) were plotted against visual field mean deviation (MD) with linear change-point analyses, measurement floors, and steps to floors. RESULTS: Mean MD (dB) for glaucomatous eyes was -5.77 (-6.45 to -5.10). The number of eyes with mild glaucoma (MD >-6), moderate glaucoma (MD -6 to -12), and severe glaucoma (MD <-12) were 164, 50, and 38, respectively. pPDZ yielded the lowest estimated floor at -26.6 dB (standard error [SE] 1.53), followed by OCTA macular metrics (-25 to -21 dB; SE 1.03) and pVAD (-17.6 dB, SE 1.06). RNFL and GCIPL produced floors at -17.8 (SE 0.927) and -23.6 dB (SE 1.14). The highest number of steps to measurement floor belonged to RNFL (7.20) and GCIPL (7.33), followed by pPDZ (4.25), mVAD (3.87), and mVSD (3.81), with 2.5 or fewer steps for pVAD, mPDZ, and mVDZ. CONCLUSIONS: pPDZ, mVAD, and mVSD had approximately 4 steps within their dynamic ranges, without true measurement floors, and thus may be useful in evaluating advanced glaucomatous progression. Improving OCTA test-retest repeatability could augment number of steps for OCTA metrics, increasing their clinical utility.

Broad internal limiting membrane peeling with adjunctive plasma-thrombin for repair of large macular holes : A retrospective case series.

PURPOSE: To assess the potential efficacy of broad internal limiting membrane peeling with adjunctive plasma-thrombin instillation to treat large macular holes and to make qualitative comparisons to internal limiting membrane peeling without adjunctive treatment and internal limiting membrane peeling with inverted and free internal limiting membrane flaps. METHODS: A systematic literature review and a retrospective case series. Participants in the case series (N = 39) had idiopathic macular holes larger than 400 µm as measured on spectral-domain optical coherence tomography and underwent pars plana vitrectomy, internal limiting membrane peeling, placement of autologous plasma and bovine thrombin over the hole, and gas tamponade. Repeat imaging and clinical data were collected from 1, 2, 3, 6, and 12 months postoperatively. RESULTS: Macular hole closure rate was 97%; 82% had U-type closures. At 12 months, 11% had defects in the external limiting membrane and 22% in the ellipsoid zone. This closure rate is similar to prior studies of internal limiting membrane flaps, while the U-type closure rate and retinal layer restoration compare favorably to those reported for internal limiting membrane peeling alone and internal limiting membrane flaps; 75% experienced a three-line improvement in visual acuity by 6 months, which exceeds results by either method. CONCLUSION: Plasma-thrombin instillation over macular holes may be a less-complicated alternative adjunct to internal limiting membrane flaps that can achieve similar outcomes when combined with internal limiting membrane peeling.

Attenuation of Inherited and Acquired Retinal Degeneration Progression with Gene-based Techniques.

Inherited retinal dystrophies cause progressive vision loss and are major contributors to blindness worldwide. Advances in gene therapy have brought molecular approaches into the realm of clinical trials for these incurable illnesses. Select phase I, II and III trials are complete and provide some promise in terms of functional outcomes and safety, although questions do remain over the durability of their effects and the prevalence of inflammatory reactions. This article reviews gene therapy as it can be applied to inherited retinal dystrophies, provides an update of results from recent clinical trials, and discusses the future prospects of gene therapy and genome surgery.