USING MICROPERIMETRY AND LOW-LUMINANCE VISUAL ACUITY TO DETECT THE ONSET OF LATE AGE-RELATED MACULAR DEGENERATION: A LEAD Study Report.

PURPOSE: To evaluate the performance of microperimetry and low-luminance visual acuity for detecting late age-related macular degeneration (AMD) onset. METHODS: Two hundred ninety-two individuals with bilateral large drusen in the Laser Intervention in the Early Stages of AMD study underwent best-corrected visual acuity, low-luminance visual acuity, and microperimetry testing as well as multimodal imaging to detect late (neovascular or atrophic) AMD onset. The performance of the change in the measurement from baseline of each of visual function test for detecting late AMD onset was compared. RESULTS: The area under the receiver operating characteristic curve for detecting neovascular and atrophic AMD onset was not significantly different for low-luminance visual acuity (area under the receiver operating characteristic curve = 0.71 and 0.56, respectively) and microperimetry (area under the receiver operating characteristic curve = 0.82 and 0.62, respectively) compared with best-corrected visual acuity (area under the receiver operating characteristic curve = 0.57 and 0.56, respectively; P ≥ 0.126 for all). There was also only a fair degree of agreement between the three visual function measures for detecting the onset of neovascular and atrophic AMD (κ ≥ 0.24). CONCLUSION: Microperimetry, low-luminance visual acuity, and best-corrected visual acuity demonstrate limited performance for detecting the earliest onset of late AMD. It remains to be established whether they perform better than current methods designed to enable self-detection of neovascular AMD onset, such as Amsler grid testing.

Aqueous Chlorhexidine for Intravitreal Injection Antisepsis: A Case Series and Review of the Literature.

PURPOSE: To determine the incidence of endophthalmitis in a large clinical series using aqueous chlorhexidine for antisepsis before intravitreal injection and to review the ophthalmic literature regarding chlorhexidine efficacy and safety. DESIGN: Multicenter retrospective case series. PARTICIPANTS: All patients receiving intravitreal injections from 7 retinal specialists. METHODS: An audit of intravitreal injections performed by retinal specialists who exclusively used aqueous chlorhexidine 0.05% or 0.1% for prophylaxis of infective endophthalmitis was undertaken. The incidence of endophthalmitis was determined from August 1, 2011, to February 28, 2015. A literature review was performed to critically appraise the ocular safety and efficacy of aqueous chlorhexidine. MAIN OUTCOME MEASURES: Incidence of endophthalmitis after intravitreal injections. RESULTS: A total of 40 535 intravitreal injections were performed by 7 retinal specialists across 3 centers. Chlorhexidine was well tolerated, and only 1 patient with a suspected allergic reaction was noted. Three cases of endophthalmitis were identified with 1 culture-positive case. The 0.0074% (1 in 13 512) per-injection rate of endophthalmitis in this series compares favorably with previous series in which povidone-iodine has been used. CONCLUSIONS: Aqueous chlorhexidine was associated with a low rate of postinjection endophthalmitis and was well tolerated by patients.

Dose Response in the Subthreshold Nanosecond Laser Trial in Early Stages of AMD: A LEAD Study Report.

BACKGROUND AND OBJECTIVE: To examine the association between treatment parameters and the progression to late age-related macular degeneration (AMD) in the Laser Intervention in Early Stages of Age-Related Macular Degeneration (LEAD) study, a randomized, controlled trial of a subthreshold nanosecond laser (SNL) for slowing disease progression in the early stages of AMD. PATIENTS AND METHODS: The association between treatment parameters early in the trial period for participants in the SNL arm of the LEAD study and time to develop late AMD during the 3-year trial duration was examined. Parameters included treatment energy at the baseline and 6-month visits and the number of laser spots visible on fundus autofluorescence (FAF) imaging taken at 6 and 12 months (taken as a proxy measure of early, adequate delivery of the laser treatment at the baseline and 6-month visits, respectively). RESULTS: A multivariable analysis revealed there were no significant associations between time to develop late AMD and number of FAF-visible laser spots at 6-months (adjusted P = .537) nor laser energy used at baseline (adjusted P = .910). No significant associations were also observed when evaluating FAF-visible spots at 12-months (adjusted P = .107) and the average laser energy used at baseline and 6 months (adjusted P = .558). CONCLUSIONS: This study did not find any evidence to suggest that there was a dose response for the effect of laser treatment using these treatment parameters on the progression of AMD. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:380-386.].

Examining the added value of microperimetry and low luminance deficit for predicting progression in age-related macular degeneration.

PURPOSE: To examine the added predictive value of microperimetric sensitivity and low luminance deficit (LLD; difference between photopic and low luminance visual acuity (VA)) to information from colour fundus photography (CFP) for progression to late age-related macular degeneration (AMD) in individuals with bilateral large drusen. METHODS: 140 participants with bilateral large drusen underwent baseline microperimetry testing, VA measurements and CFP. They were then reviewed at 6-monthly intervals to 36 months, to determine late AMD progression. Microperimetry pointwise sensitivity SD (PSD), LLD and the presence of pigmentary abnormalities on CFPs were determined. Predictive models based on these parameters were developed and examined. RESULTS: Baseline microperimetry PSD and presence of pigmentary abnormalities were both significantly associated with time to develop late AMD (p≤0.004), but LLD was not (p=0.471). The area under the receiver operating characteristic curve (AUC) for discriminating between eyes that progressed to late AMD based on models using microperimetry PSD (AUC=0.68) and LLD (AUC=0.58) alone was significantly lower than that based on CFP grading for the presence of pigmentary abnormalities (AUC=0.80; both p<0.005). Addition of microperimetry and/or LLD information to a model that included CFP grading did not result in any improvement in its predictive performance (AUC=0.80 for all; all p≥0.66). CONCLUSIONS: While microperimetry, but not LLD, was significantly and independently associated with AMD progression at the population level, this study observed that both measures were suboptimal at predicting progression at the individual level when compared to conventional CFP grading and their addition to the latter did not improve predictive performance.

Properties of the Impact of Vision Impairment and Night Vision Questionnaires Among People With Intermediate Age-Related Macular Degeneration.

PURPOSE: To explore the psychometric properties of the Impact of Vision Impairment (IVI-28) and Night Vision Questionnaires (NVQ-10) among people with intermediate age-related macular degeneration (iAMD). METHODS: Baseline responses were collected from 288 participants (aged 50-88 years, 74% female) in the Laser intervention in Early stages of Age-related macular Degeneration (LEAD) study in Australia and Northern Ireland. Psychometric properties (discrimination, ordering of thresholds, person separation, item miss-fit, and differential item functioning according to sex) were explored using grouped rating scale and partial credit models. Spearman's correlation was estimated to assess the association with measures of visual function (mean mesopic microperimetric sensitivity, best-corrected visual acuity, low-luminance visual acuity, and low-luminance deficit). The psychometric properties were then explored following recalibration of the instruments. RESULTS: In this homogenous population, ceiling effects caused by relatively high levels of functional vision were evident for both instruments. The IVI-28 and NVQ-10 displayed suboptimal discrimination between levels of functional vision in iAMD and poor targeting among people with iAMD. The correlation between ability scores and measures of visual function was mild. In general, the NVQ-10 showed superior psychometric properties to the IVI-28 among these participants. No significant improvement in reliability could be gained following recalibration. CONCLUSIONS: Both instruments were designed for populations with more severe visual loss and poorly discriminate in this cohort of iAMD. TRANSLATIONAL RELEVANCE: New instruments that can capture the subtle changes in functional vision that occur early in AMD are required to aid evaluation of emerging interventions for iAMD.