Is selective laser trabeculoplasty shifting the glaucoma treatment paradigm in developing countries?

In 2019, the Laser in Glaucoma and Ocular Hypertension (LiGHT) randomised controlled trial reported that initial treatment with selective laser trabeculoplasty (SLT) is more cost effective than initial treatment with pressure-lowering eye drops, leading to a reduced number of glaucoma surgeries and very low rates of adverse events while providing drop-free intraocular pressure (IOP) control to 78% of treated eyes after 3 years.1 2 As a result, the European Glaucoma Society,3 the American Academy of Ophthalmology4 and the UK National Institute for Health and Care Excellence5 now recommend the use of SLT as initial treatment for open-angle glaucoma (OAG) and ocular hypertension (OHT)

Validation of the RCOphth and UKEGS glaucoma risk stratification tool 'GLAUC-STRAT-fast'

BACKGROUND/AIMS: The aim of this study was to validate the Glaucoma Risk Stratification Tool (GLAUC-STRAT-fast) currently recommended by the Royal College of Ophthalmologists for the risk stratification of patients with glaucoma in the UK National Health Service Hospital Eye Service. METHODS: GLAUC-STRAT fast was applied to the LiGHT trial participants by risk-stratifying the worse eye of each patient at baseline and after 3 years of treatment. Metrics of disease severity or treatment intensity used for the validation were: increased number of monitoring visits or treatment escalations; needing a trabeculectomy; a reduction of >2 dB in visual field mean deviation (VF MD) during the monitoring period; identification of rapid VF loss on total (TD) and/or pattern deviation (PD). The proportion of eyes within each baseline stratum for each of the above markers was compared against the other strata, using a χ2 test for proportions. RESULTS: There was an association between the baseline stratification and the number of treatment escalations needed to maintain the eye-specific target intraocular pressure (p=0.001), the number of visits needed throughout the 3-year follow-up period (p=0.001), the need for trabeculectomy (p<0.001) and absolute loss of MD over the course of the monitoring period (p<0.001). The rate of VF progression was not associated with baseline risk stratification for TD or PD progression (p≥0.007, with Bonferroni correction). CONCLUSION: The GLAUC-STRAT fast tool is a useful tool for risk stratifying eyes with ocular hypertension or open angle glaucoma. Further research is needed to confirm and validate its applicability to more advanced glaucomas and generalisability to clinical use. TRIAL REGISTRATION NUMBER: The LiGHT trial is registered at controlled-trials.com (ISRCTN32038223)

Treatment expectations in glaucoma: what matters most to patients?

Background/Objectives: Recent clinical trials in glaucoma have used patient-reported outcome measures (PROMs) of health-related quality of life to evaluate interventions. However, existing PROMs may not be sufficiently sensitive to capture changes in health status. This study aims to determine what really matters to patients by directly exploring their treatment expectations and preferences. Subjects/Methods: We conducted a qualitative study using one-to-one semi-structured interviews to elicit patients’ preferences. Participants were recruited from two NHS clinics serving urban, suburban and rural populations in the UK. To be relevant across glaucoma patients under NHS care, participants were sampled to include a full range of demographic profiles, disease severities and treatment histories. Interview transcripts were evaluated using thematic analysis until no new themes emerged (saturation). Saturation was established when 25 participants with ocular hypertension, mild, moderate and advanced glaucoma had been interviewed. Results: Themes identified were: Patients’ experiences of living with glaucoma, patients’ experiences of having glaucoma treatment, most important outcomes to patients, and COVID-related concerns. Participants specifically expressed their most important concerns, which were (i) disease-related outcomes (intraocular pressure control, maintaining vision, and being independent); and (ii) treatment-related outcomes (treatment that does not change, drop-freedom, and one-time treatment). Both disease-related and treatment-related experiences were covered prominently in interviews with patients across the spectrum of glaucoma severity. Conclusions: Outcomes related both to the disease and its treatment are important to patients with different severities of glaucoma. To accurately evaluate quality of life in glaucoma, PROMs may need to assess both disease-related and treatment-related outcomes

Minimising bias in an un-masked, pragmatic rct comparing two treatment pathways for glaucoma by the use of decision support software - the light trial experience

ragmatic trials of treatment pathways can require patient awareness of treatment allocation in order to better represent clinical reality, for example when concordance with a treatment has an important effect on outcome. Conversely, masking of treating clinicians to allocation group can be impossible when full clinical assessment requires knowledge of the current treatments, resources do not permit separate teams for treatment and assessment or when such duplication of clinician contact might affect an outcome such as patient experience. The LiGHT trial is a 718 subject multi-centre 6-year NIHR-funded study of two treatment pathways for glaucoma with outcome measures of health related quality of life and cost effectiveness. We aimed to minimise variation in aspects of clinical behaviour that might introduce bias by affecting either of these outcomes

Automated Pupillometry Using a Prototype Binocular Optical Coherence Tomography System

PURPOSE: To determine the test-retest reliability and diagnostic accuracy of a binocular optical coherence tomography (OCT) prototype (Envision Diagnostics, USA) for pupillometry. DESIGN: Assessment of diagnostic reliability and accuracy. METHODS: Fifty participants with RAPD confirmed using the swinging flashlight method (mean age 49.6 years) and 50 healthy controls (mean age 31.3 years) were examined. Participants twice underwent an automated pupillometry exam using a binocular OCT system that presents a stimulus and simultaneously captures OCT images of the iris-pupil plane of both eyes. Participants underwent a single exam on the RAPDx (Konan Inc, USA), an automated infrared pupillometer. Pupil parameters including maximum and minimum diameter, and anisocoria were measured. The magnitude of RAPD was calculated using the log of the ratio of the constriction amplitude between the eyes. A pathological RAPD was considered to be above ±0.5 log units on both devices. RESULTS: Intraclass correlation coefficient was >0.90 for OCT-derived maximum pupil diameter, minimum pupil diameter, anisocoria. The RAPDx had a sensitivity of 82% and a specificity of 94% for detection of RAPD whereas the binocular OCT had a sensitivity of 74% and specificity of 86%. The diagnostic accuracy of the RAPDx and binocular OCT was 88% (CI: 80-94%) and 80% (CI: 71-87%) respectively. CONCLUSIONS: Binocular OCT-derived pupil parameters had excellent test-retest reliability. Diagnostic accuracy of RAPD was inferior to the RAPDx and is likely related to factors such as eye movement during OCT capture. As OCT becomes ubiquitous, OCT-derived measurements may provide an efficient method of objectively quantifying the pupil responses

Laser in Glaucoma and Ocular Hypertension Trial (LIGHT) in China - A Randomized Controlled Trial: Design and Baseline Characteristics

PURPOSE: To describe the baseline characteristics of a trial to evaluate whether selective laser trabeculoplasty (SLT), as a first-line treatment, provides superior economic and health-related quality of life outcomes to medical treatment in China. DESIGN: The LiGHT China trial is an unmasked, single-center, pragmatic, randomized controlled trial. METHODS: A total of 771 previously undiagnosed patients with primary open angle glaucoma (POAG, 622 patients) or ocular hypertension (OHT, 149 patients) at Zhongshan Ophthalmic Center were recruited from March 2015 to January 2019. Subjects were randomized to SLT-1st (followed by medication then surgery when required) or Medicine-1st (medication followed by surgery when required). The primary outcome was health-related quality of life (HRQL). The secondary outcomes were clinical outcomes, cost, cost-effectiveness, Glaucoma Utility Index, Glaucoma Symptom Scale, visual function, and safety. RESULTS: The mean age of POAG patients was 49.8 years and 38.8 years for OHT. The median intraocular pressure was 20 mm Hg for the 1,105 POAG eyes and 24 mm Hg for the 271 OHT eyes. POAG eyes had thinner central cornea thickness (CCT, 536 µm) than OHT eyes (545 µm). Median mean deviation of the visual field in POAG eyes was -4.2 dB. Median refractive error was -1.5 D for OHT eyes and -1.25 D for POAG eyes. There was no difference between POAG and OHT patients on baseline scores of GUI, GSS and VF-14. The difference between OHT and POAG on the EQ-5D-5L was 0.024. CONCLUSIONS: Compared with participants in the LiGHT UK trial, participants in this trial were younger, more myopic and had more severe visual field defects

Intraocular pressure and diurnal fluctuation of open-angle glaucoma and ocular hypertension: a baseline report from the LiGHT China trial cohort

AIMS: To report the baseline intraocular pressure (IOP) characteristics and its diurnal fluctuation in the Laser in Glaucoma and Ocular Hypertension China cohort. METHODS: 622 primary open-angle glaucoma (POAG) patients and 149 ocular hypertension (OHT) patients were recruited at Zhongshan Ophthalmic Center from 2015 to 2019. Standardised ocular examinations were performed including IOP measurement using the Goldmann applanation tonometer. Daytime phasing IOP was recorded at 8:00, 10:00, 11:30, 14:30, 17:00 hour. RESULTS: The mean baseline IOP was 20.2 mm Hg for POAG patients and 24.4 mm Hg for OHT. Multiple regression analysis revealed that thicker central corneal thickness (CCT) was correlated with higher IOP in both POAG and OHT. Male gender and younger age were correlated with higher IOP only for POAG. As for diurnal IOP fluctuation, mean IOP fluctuation was 3.4 mm Hg in POAG eyes and 4.4 mm Hg in OHT. The peak and trough IOP occurred at 8:00 and 14:30 hour in both POAG and OHT eyes. CONCLUSIONS: Younger age, male gender and thicker CCT are correlated to higher IOP in POAG patients while only thicker CCT is related to higher IOP in OHT patients. Peak IOP appears mostly at early morning or late afternoon and trough value occurs mostly at early afternoon

LiGHT trial: 6-year results of primary selective laser trabeculoplasty versus eye drops for the treatment of glaucoma and ocular hypertension

PURPOSE: The LiGHT trial has shown selective laser trabeculoplasty (SLT) to be clinically and cost-effective as a primary treatment of open-angle glaucoma (OAG) and ocular hypertension (OHT) at 3 years. This paper reports health-related quality of life (HRQL) and clinical effectiveness of initial treatment with SLT compared to intra-ocular pressure (IOP) lowering eye drops, after 6 years of treatment. DESIGN: Prospective multicentre randomized controlled trial. PARTICIPANTS: Treatment-naïve eyes with OAG or OHT, initially treated with SLT or IOP-lowering drops. METHODS: Patients were randomly allocated to initial SLT or eye drops. Eye specific target IOP and monitoring intervals were based on international guidelines. After the initial 3 years of the trial, patients in the SLT arm were permitted a 3rd SLT if necessary; patients in the drops arm were allowed SLT as a treatment switch or escalation. Analysis was by intention to treat. This study is registered at controlled-trials.com (ISRCTN32038223). MAIN OUTCOME MEASURES: The primary outcome was HRQL at 6 years; secondary outcomes were clinical effectiveness and safety. RESULTS: Of the 692 patients completing 3 years in the LiGHT trial, 633 (91.5%) entered the extension and 524 patients completed 6 years in the trial (82.8% of those entering the extension phase, 73% of those initially randomised). At 6 years, there were no significant differences in HRQL for EQ-5D, GUI and GQL-15 (all p>0.05). The SLT arm had better GSS scores than the drops arm (83.6 (SD 18.1) vs 81.3 (SD 17.3), respectively). 69.8% of eyes in the SLT arm remained at or below target IOP without the need for medical or surgical treatment. More eyes in the drops arm exhibited disease progression (26.8% vs 19.6%, respectively, p=0.006). Trabeculectomy was required in 32 eyes in the drops arm compared to 13 eyes in the SLT arm (p<0.001); there were more cataract surgeries in the drops arm (95 compared to 57 eyes, p=0.03). There were no serious laser-related adverse events. CONCLUSIONS: SLT is a safe treatment for OAG and OHT, providing better long-term disease control than initial drop therapy, with reduced need for incisional glaucoma and cataract surgery over 6 years