This study showed that the cross-sectional area of retinal tissue between the plexiform layers in cystoid macular edema, as imaged by OCT, is the best indicator of visual function at baseline. Further prospective treatment trials are needed to investigate this parameter as a predictor of visual outcome after intervention.

The osteo-odonto-keratoprosthesis (OOKP), although described over 40 years ago, remains the keratoprosthesis of choice for end-stage corneal blindness not amenable to penetrating keratoplasty. It is particularly resilient to a hostile environment such as the dry keratinized eye resulting from severe Stevens-Johnson syndrome, ocular cicatricial pemphigoid, trachoma, and chemical injury. Its rigid optical cylinder gives excellent image resolution and quality. The desirable properties of the theoretical ideal keratoprosthesis is described. The indications, contraindications, and patient assessment (eye, tooth, buccal mucosa, psychology) for OOKP surgery are described. The surgical and anaesthetic techniques are described. Follow-up is life-long in order to detect and treat complications, which include oral, oculoplastic, glaucoma, vitreo-retinal complications and extrusion of the device. Resorption of the osteo-odonto-lamina is responsible for extrusion, and this is more pronounced in tooth allografts. Regular imaging with spiral-CT or electron beam tomography can help detect bone and dentine loss. The optical cylinder design is discussed. Preliminary work towards the development of a synthetic OOKP analogue is described. Finally, we describe how to set up an OOKP national referral center.

Purpose: Blue-blocking (BB) spectacle lenses, which attenuate short-wavelength light, are being marketed to alleviate eyestrain and discomfort when using digital devices, improve sleep quality and potentially confer protection from retinal phototoxicity. The aim of this review was to investigate the relative benefits and potential harms of these lenses. Methods: We included randomised controlled trials (RCTs), recruiting adults from the general population, which investigated the effect of BB spectacle lenses on visual performance, symptoms of eyestrain or eye fatigue, changes to macular integrity and subjective sleep quality. We searched MEDLINE, EMBASE, the Cochrane Library and clinical trial registers, until 30 April 2017. Risk of bias was assessed using the Cochrane tool. Results: Three studies (with 136 participants) met our inclusion criteria; these had limitations in study design and/or implementation. One study compared the effect of BB lenses with clear lenses on contrast sensitivity (CS) and colour vision (CV) using a pseudo-RCT crossover design; there was no observed difference between lens types (log CS; Mean Difference (MD) = À0.01 [À0.03, 0.01], CV total error score on 100-hue; MD = 1. 30 [À7.84, 10.44]). Another study measured critical fusion frequency (CFF), as a proxy for eye fatigue, on wearers of low and high BB lenses, pre-and post-a two-hour computer task. There was no observed difference between low BB and standard lens groups, but there was a less negative change in CFF between the high and low BB groups (MD = 1. 81 [0.57, 3.05]). Both studies compared eyestrain symptoms with Likert scales. There was no evidence of inter-group differences for either low BB (MD = 0.00 [À0.22, 0.22]) or high BB lenses (MD = À0.05 [À0.31, 0.21]), nor evidence of a difference in the proportion of participants showing an improvement in symptoms of eyestrain or eye fatigue. One study reported a small improvement in sleep quality in people with self-reported insomnia after wearing high compared to low-BB lenses (MD = 0.80 [0.17, 1.43]) using a 10-point Likert scale. A study involving normal participants found no observed difference in sleep quality. We found no studies investigating effects on macular structure or function. Conclusions: We find a lack of high quality evidence to support using BB spectacle lenses for the general population to improve visual performance or sleep quality, alleviate eye fatigue or conserve macular health.

OOKP surgery can restore useful and lasting vision in patients suffering from end-stage ocular surface disease, for whom conventional corneal surgery is not possible. The main problems seen in this study were laminar resorption, particularly in allografts, and glaucoma.

Purpose:To review the published scientific literature concerning clinical and material degradations of intraocular lenses after implantation in cataract surgery.Methods:A search was undertaken using the following databases: CENTRAL (including Cochrane Eyes and Vision Trials Register; The Cochrane Library: Issue 2 of 12 February 2019), Ovid MEDLINE (R) without Revisions (1996 to February week 2, 2019), Ovid MEDLINE (R) (1946 to February week 2, 2019), Ovid MEDLINE (R) Daily Update 19 February 2019, MEDLINE and MEDLINE non-indexed items, Embase (1980–2019, week 7), Embase (1974–2019, 19 February), Ovid MEDLINE (R) and Epub Ahead of Print, in-Process & Other Non-Indexed Citations and Daily (1946 to 19 February 2019), Web of Science (all years), the metaRegister of Controlled Trials ( mRCT) ( www.controlled-trials.com ), ClinicalTrials.gov ( www.clinicaltrial.gov ) and the WHO International Clinical Trials Registry Platform ( www.who.int/ictrp/search/en ). Only published articles in English were selected. Search terms/keywords included ‘IOL’ or ‘intraocular lens’, combined with ‘opacification’, degradation, glistenings, nanoglistenings, whitening, transmittance, light scatter, discolouration/discoloration, performance, quality, material, biocompatibility, calcification, explantation and ultraviolet/UV radiation. Relevant in-article references not returned in our searches were also considered.Results:After review of the available articles, the authors included 122 publications in this review, based on the quality of their methodology and their originality. The studies included in this review were randomized controlled trials, cohort studies, case-controlled studies, case series, case reports, laboratory studies and review papers. Differing material degradations of intraocular lenses have been described and their associated pathophysiology studied. Reported anomalies include photochemical alterations, water vacuoles, internal and surface calcific deposits, surface coatings and discolouration. The nature of such changes has been shown to depend on the type of intraocular lenses material used and/or manufacturing processes and storage conditions employed. Changes in the intraocular lens can also be influenced by surgical technique, coexisting ocular pathologies and topical and systemic medications. The clinical significance of these degradations is variable, with some resulting in significant visual disturbance and the need for intraocular lens explantation and others producing only minimal visual impairments. Failure to recognize the precise nature of the problem may lead to unnecessary laser capsulotomy procedures.Conclusion:Clinical degradations of intraocular lenses are uncommon but have been reported following the implantation of intraocular lenses made of differing biomaterials. Their correct identification and thorough investigation to determine the underlying cause is necessary for optimal patient management and the prevention of such problems. Choosing a lens made of a particular material may be important in patients with certain ocular conditions.

Purpose: To compare the Clareon® (Alcon Laboratories, Inc.) intraocular lens to theTecnis PCB00® (Johnson & Johnson Inc.) in terms of visual performance, refractive outcomes, glistenings occurrence and quality of life outcomes.

ObjectiveTo investigate the effect of intraocular lens (IOL) glistenings on visual performance and evaluate a new glistenings grading methodology.Methods and AnalysisThirty-four patients (34 eyes) were recruited. Corrected distance visual acuity (CDVA), mesopic gap acuity (MGA), functional contrast sensitivity (FCS) and forward light scatter were measured (Advanced Vision and Optometric Tests, City Occupational, London, UK). The IOL centre was imaged and glistenings density graded by three observers using the Miyata scale and a new system. Inter-rater reliability, association between the two grading scales, and correlations between glistenings grades and visual performance parameters were evaluated.ResultsThe intraclass correlation coefficient between graders for the new grading system was 0.769 (95% Confidence Interval [CI] 0.636 to 0.868). There was a significant association between the Miyata scale and the new grading system for all graders (rs=0.533–0.895, p≤0.001). There was no association between CDVA or MGA and glistenings grade (rs=− 0.098, p=0.583 and rs=0.171, p=0.359, respectively). There was no association between FCS at mesopic light levels and glistenings grade (rs=−0.032, p=0.864), or the straylight parameter and glistenings grade (rs=0.021, p=0.916). No association was found between the integrated straylight parameter and glistenings grade (rs=0.078, p=0.701).ConclusionThe new glistenings grading scale was highly reproducible. In this cohort, glistenings in the same hydrophobic acrylic IOL after cataract surgery were not associated with changes in visual function, as assessed by a series of tests not previously used in glistenings research.

Surface wettability and hydrophilicity of pHEMA soft contact lenses were investigated utilising adherent liquid/laser method (ALLM) and adherent liquid/balance method (ALBM). The measurements were carried out before and after periods of 15 min to 2 h contact lens wear. Following the lens removal, the wetting angle of the contact lens of the left eyes and hydrophilicity (maximum force) of the contact lens of the right eyes of the five subjects were immediately measured, respectively, without cleaning (one value for pre-lens wear and eight values for post-lens wear). The wettability of soft contact lenses significantly increased after 15 min of wearing and stabilised at a maximum level after 30 min in vivo. Contact lens hydrophilicity was found to decrease as the lens was worn. The reduction continued for up to 1.5 h of wearing, for male cases, and for the female cases, the reduction continued until the end of the experiment.