Dataset Information

Next Generation PERG Method: Expanding the Response Dynamic Range and Capturing Response Adaptation.

ABSTRACT: PURPOSE:To compare a new method for steady-state pattern electroretinogram (PERGx) with a validated method (PERGLA) in normal controls and in patients with optic neuropathy. METHODS:PERGx and PERGLA were recorded in a mixed population (n = 33, 66 eyes) of younger controls (C1; n = 10, age 38 ± 8.3 years), older controls (C2; n = 11, 57.9 ± 8.09 years), patients with early manifest glaucoma (G; n = 7, 65.7 ±11.6 years), and patients with nonarteritic ischemic optic neuropathy (N; n = 5, mean age 59.4 ± 8.6 years). The PERGx stimulus was a black-white horizontal grating generated on a 14 × 14 cm LED display (1.6 cycles/deg, 15.63 reversals/s, 98% contrast, 800 cd/m2 mean luminance, 25° field). PERGx signal and noise were averaged over 1024 epochs (?2 minutes) and Fourier analyzed to retrieve amplitude and phase. Partial averages (16 successive samples of 64 epochs each) were also analyzed to quantify progressive changes over recording time (adaptation). RESULTS:PERGLA and PERGx amplitudes and latencies were correlated (Amplitude R2 = 0.59, Latency R2 = 0.39, both P < 0.0001) and were similarly altered in disease. Compared to PERGLA, however, PERGx had shorter (16 ms) latency, higher (1.39×) amplitude, lower (0.37×) noise, and higher (4.2×) signal-to-noise ratio. PERGx displayed marked amplitude adaptation in C1 and C2 groups and no significant adaptation in G and N groups. CONCLUSIONS:The PERGx high signal-to-noise ratio may allow meaningful recording in advanced stages of optic nerve disorders. In addition, it quantifies response adaptation, which may be selectively altered in glaucoma and optic neuropathy. TRANSLATIONAL RELEVANCE:A new PERG method with increased dynamic range allows recording of retinal ganglion cell function in advanced stages of optic nerve disorders. It also quantifies the response decline during the test, an autoregulatory adaptation to metabolic challenge that decreases with age and presence of disease.

SUBMITTER: Monsalve P

PROVIDER: S-EPMC5444497 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Next Generation PERG Method: Expanding the Response Dynamic Range and Capturing Response Adaptation.

Monsalve Pedro P Triolo Giacinto G Toft-Nielsen Jonathon J Bohorquez Jorge J Henderson Amanda D AD Delgado Rafael R Miskiel Edward E Ozdamar Ozcan O Feuer William J WJ Porciatti Vittorio V

Translational vision science & technology 20170522 3

<h4>Purpose</h4>To compare a new method for steady-state pattern electroretinogram (PERGx) with a validated method (PERGLA) in normal controls and in patients with optic neuropathy.<h4>Methods</h4>PERGx and PERGLA were recorded in a mixed population (<i>n</i> = 33, 66 eyes) of younger controls (C1; <i>n</i> = 10, age 38 ± 8.3 years), older controls (C2; <i>n</i> = 11, 57.9 ± 8.09 years), patients with early manifest glaucoma (G; <i>n</i> = 7, 65.7 ±11.6 years), and patients with nonarteritic isc ...[more]

PMID: 28553559

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Dataset Information

Next Generation PERG Method: Expanding the Response Dynamic Range and Capturing Response Adaptation.

Publications

Next Generation PERG Method: Expanding the Response Dynamic Range and Capturing Response Adaptation.

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