Wide-field Trend-based Progression Analysis of Combined Retinal Nerve Fiber Layer and Ganglion Cell Inner Plexiform Layer Thickness

Nicotinamide Riboside as a Neuroprotective Therapy for Glaucoma Study Protocol for a Randomized, Double-blind, Placebo-control Trial

“…In our pilot study following 236 glaucoma patients every 4 months for ≥3 years, the mean rate of RNFL thinning was 1.2µm/year (P<0.001) for eyes with evidence of progressive RNFL thinning detected by TPA; the slope variance was 1.39(µm/year) 2 and the residual variance was 3.83µm 2 . 20 We aim to detect a difference of at least 0.70µm/year in the rate of RNFL thinning between treatment groups, a rate slightly greater than the mean rate of age-related RNFL thinning, which has been reported to be approximately 0.52µm/year. 22 Taking reference from the method of sample size calculation for linear mixed modeling to compare the rates of change of a parameter of interest between two treatment groups described by Ard and Edland, 23 53 patients per study arm are needed for serial RNFL thickness measurements at baseline, 1 month, 4 months, and then every 2 months for 24 months (3 separate measurements will be collected at the baseline, 1-month, and 24-month follow-up visits) with a power of 80% and an alpha of 5%.…”

“…Inclusion criteria are as follows: age ≥18 years; best corrected VA ≥20/40; IOP ≤28mmHg; and evidence of progressive RNFL/GCIPL thinning detected by Guided Progression Analysis (GPA) or Trend-based Progression Analysis (TPA) in one or both eyes. [17][18][19][20] Exclusion criteria are as follows: pathological myopia; diseases that may cause visual eld loss or optic disc abnormalities other than glaucoma; inability to perform reliable visual eld; suboptimal quality of OCT images; diabetic retinopathy/maculopathy; and a history of abnormal liver function within 12 months.…”

“…The algorithm of TPA has been described. 17,18,20 In brief, TPA performs pixel-by-pixel linear regression analysis between RNFL/GCIPL thickness and time for evaluation of progressive RNFL/GCIPL thinning after registering and aligning serial OCT scans in corresponding retinal locations of an eye. To minimize type I errors consequential to multiple testing in an eye, the RNFL-GCIPL thickness maps will be condensed from 512x256 pixels to 128x64 superpixels with a false discovery rate (FDR) controlled at 5%.…”

Re: Wu et al.: Wide-field trend-based progression analysis of combined retinal nerve fiber layer and ganglion cell inner plexiform layer thickness (Ophthalmology. 2020;127:1322-1330)

“…TO THE EDITOR: We read the article by Wu et al 1 Attempts to use wide-field OCT data for evaluating the structural progression of glaucoma are interesting and necessary for understanding the spatial relationship between the peripapillary and macular areas. Our group also introduced a combination method that integrates the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion celleinner plexiform layer (GCIPL) guided progression analysis (GPA) progression maps (Cirrus HD-OCT software, version 10.0, Carl Zeiss Meditec, Inc) into a single image (we refer to this map as a "wide-field GPA map" or "GPA PanoMap"), which helps us to evaluate the temporal sequence or patterns of the glaucomatous structural progression.…”

“…REPLY: We thank Dr Lee et al for their interest in our study. 1 We are well aware of their cardinal work in applying guided progression analysis (GPA; Carl Zeiss Meditec), an event-based analysis, to evaluate changes in parapapillary retinal nerve fiber layer (RNFL) thickness and macular ganglion cell inner plexiform layer (GCIPL) thickness in patients with glaucoma. As shown in our earlier studies, 2,3 trendbased progression analysis (TPA) outperforms GPA in enabling earlier detection of progressive RNFL thinning and providing spatial information of its rates of change.…”