Photobiomodulation for non-exudative age-related macular degeneration

BACKGROUND: Age‐related macular degeneration (AMD) is one of the leading causes of blindness in high‐income countries. The majority of cases of AMD are of the non‐exudative type. Experts have proposed photobiomodulation (PBM) therapy as a non‐invasive procedure to restore mitochondrial function, upregulate cytoprotective factors and prevent apoptotic cell death in retinal tissue affected by AMD. OBJECTIVES: To assess the effectiveness and safety of PBM compared to standard care, no treatment or sham treatment for people with non‐exudative AMD. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (Issue 5, 2020), Ovid MEDLINE, Embase, ISRCTN, ClinicalTrials.gov and the WHO ICTRP to 11 May 2020 with no language restrictions. SELECTION CRITERIA: The review included randomised controlled trials (RCTs) on participants receiving any type of PBM therapy for non‐exudative AMD compared to standard care, sham treatment or no treatment. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We considered the following outcome measures at 12 months: best‐corrected visual acuity (BCVA) ; contrast sensitivity; near vision; low luminance density score; reading speed; vision‐related quality of life score; and adverse events such as progression of AMD and conversion to exudative AMD. We graded the certainty of the evidence using GRADE. MAIN RESULTS: We included two published RCTs from single centres in the UK and Canada, which recruited 60 participants (60 eyes) and 30 participants (46 eyes) respectively. Participants in these trials were people with non‐exudative AMD with Age‐Related Eye Disease Study (AREDS) categories 2 to 4. One study compared single wavelength PBM with no treatment. This study was at risk of performance bias because the study was not masked, and there was attrition bias. One study compared multi‐wavelength PBM with sham treatment and conflicts of interest were reported by study investigators. We also identified three eligible ongoing RCTs from searching the clinical trials database. When comparing PBM with sham treatment or no treatment for non‐exudative AMD, there was no evidence of any meaningful clinical difference in BCVA at 12 months (mean difference (MD) 0.02 logMAR, 95% confidence interval (CI) ‐0.02 to 0.05; 2 RCTs, 90 eyes; low‐certainty evidence). One study comparing multi‐wavelength PBM with sham treatment showed an improvement in contrast sensitivity at Level E (18 cycles/degree) at 12 months (MD 0.29 LogCS, 95% CI 0.23 to 0.35; 1 RCT, 46 eyes; low‐certainty evidence). Visual function and health‐related quality of life scores were comparable between single wavelength PBM and no treatment groups at 12 months (VFQ‐48 score MD 0.43, 95% CI ‐0.17 to 1.03; P = 0.16; 1 RCT, 47 eyes; low‐certainty evidence). When comparing PBM with sham treatment or no treatment for non‐exudative AMD, there was no evidence of any meaningful clinical difference in conversion to exudative AMD (risk ratio (RR) 0.97, 95% CI 0.17 to 5.44; 2 RCTs, 96 eyes; very low‐certainty evidence) at 12 months. There was inconclusive evidence that single wavelength PBM prevents the progression of AMD (RR 0.79, 95% CI 0.41 to 1.53; P = 0.48; 1 RCT, 50 eyes; low‐certainty evidence). Disease progression was defined as the development of advanced AMD or significant increase in drusen volume. No included study reported near vision, low luminance vision or reading speed outcomes

Incidence of submacular haemorrhage (SMH) in Scotland : a Scottish Ophthalmic Surveillance Unit (SOSU) study

PURPOSE: Submacular haemorrhage (SMH) is a cause of severe visual loss in neovascular age-related macular degeneration (nAMD). The incidence is uncertain and furthermore there is no widely used classification system nor agreed best practice. The aim of this national surveillance study was to identify the incidence, presenting features and clinical course of new fovea-involving submacular haemorrhage associated with nAMD. METHODS: A questionnaire was sent monthly to every ophthalmic specialist in Scotland over a 12-month period asking them to report all newly presenting patients with acute SMH secondary to nAMD of at least two disc diameters (DDs) in greatest linear diameter. A follow-up questionnaire was sent 6 months after initial presentation. Cases related to other causes were excluded. RESULTS: Twenty-nine cases were reported giving an incidence of 5.4 per million per annum (range 2-15). The mean age was 83 years (range 66-96) and females accounted for 17/29 (59%). Fifteen of the 29 cases (52%) had a past history of AMD, of which 7 had nAMD. Nineteen of the 29 cases (66%) presented within 7 days of onset and the majority had SMH of < 11 DD (20/29, 69%). Treatment options comprised the following: observation (n = 6, 21%), anti-VEGF alone (n = 6, 21%) or vitrectomy with co-application of tissue plasminogen activator (TPA), anti-VEGF and gas (n = 17, 58%). The vitrectomy group experienced the greatest change in vision from logMAR 1.89-1.50 (p = 0.374). Four of 20 (20%) cases with 6 months follow-up suffered a re-bleed at a mean time of 96 days. CONCLUSIONS: The incidence, clinical features and course of a consecutive national cohort of patients with SMH secondary to nAMD are presented

Movement of the inner retina complex during the development of primary full-thickness macular holes: implications for hypotheses of pathogenesis

Background: The inner retinal complex is a well-defined layer in spectral-domain OCT scans of the retina. The central edge of this layer at the fovea provides anatomical landmarks that can be observed in serial OCT scans of developing full-thickness macular holes (FTMH). Measurement of the movement of these points may clarify the mechanism of FTMH formation. Method: This is a retrospective study of primary FTMH that had a sequence of two OCT scans showing progression of the hole. Measurements were made of the dimensions of the hole, including measurements using the central edge of the inner retinal complex (CEIRC) as markers. The inner retinal separation (distance between the CEIRC across the centre of the fovea) and the Height-IRS (average height of CEIRC above the retinal pigment epithelium) were measured. Results: Eighteen cases were identified in 17 patients. The average increase in the base diameter (368 microns) and the average increase in minimum linear dimension (187 microns) were much larger than the average increase in the inner retinal separation (73 microns). The average increase in Height-IRS was 103 microns. Conclusion: The tangential separation of the outer retina to produce the macular hole is much larger than the tangential separation of the inner retinal layers. A model based on the histology of the Muller cells at the fovea is proposed to explain the findings of this study