Age-related alterations in retinal function

Abstract

Age-related visual deficits that occur in the absence of recognized visual disease are frequently observed. Many of the optical factors contributing to these deficits have been delineated, but the contributing neurophysiological alterations have not been clearly defined. This investigation examined age-related variations in the retinal and cortical processing of visual information. Pattern-specific retinal potentials (pattern electroretinogram or PERG in this series) and cortical potentials (VECPs) were recorded from nine young visual normals (20-30 years) and nine healthy elderly individuals (70-80 years). All subjects had best corrected visual acuity of 20/30 or better. Checkerboard patterns (7.5-60 min. checks) were modulated in a counterphase mode (2.0 and 7.5 rps). PERGs and VECPs were simultaneously recorded. Significant age-related alterations in waveform amplitude and latency were observed for both biopotentials. The VECP alterations were largely the result of the reduction in retinal illumination associated with senile miosis, but this factor could not account for most of the observed PERG alterations. These results suggest that neurophysiological changes in the retina may underlie some of the visual deficits observed in healthy elderly adults.

A 3-Year Follow-Up Study of Ocular Hypertension by Pattern Electroretinogram

“…Senile miosis, increased opacities of the optic media, presbyopia or a decreased number of retinal ganglion cells with age are pointed out to explain age-relat ed decreases in the PERG amplitude [27][28][29][30][31]. A 40-month difference between the first and the follow-up PERG recording in our series may cause a reduced record of amplitude; however, our study on the two age groups of controls, 33 and 45 years, rules out this possi bility.…”

“…Several reports are available to show that the PERG amplitude is progressively reduced with aging [27][28][29][30][31]. Senile miosis, increased opacities of the optic media, presbyopia or a decreased number of retinal ganglion cells with age are pointed out to explain age-relat ed decreases in the PERG amplitude [27][28][29][30][31].…”

Reproducibility of Pattern Electroretinogram in Glaucoma Patients with a Range of Severity of Disease with the New Glaucoma Paradigm

“…The large test-retest variability reported in some studies (as high as 100% of coefficient of variation) entertained doubts concerning its clinical usefulness. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] Reproducibility is affected by details of the recording techniques, including the nature of the stimuli, as well as electrode sites and types. 20-36 PERGLA was developed in hopes that attention to technical details, use of comfortable electrodes, and empirically optimized stimuli with signal averaging would permit the pattern electroretinogram to be clinically practical and more reproducible.…”

“…20-28 Several contradictory studies have been published regarding pattern electroretinogram reproducibility. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] Recently, a new pattern electroretinogram paradigm tailored for use in glaucoma (PERGLA) was introduced to render the pattern electroretinogram testing more user-friendly and clinically useful by easing its execution and interpretation. 24,37 PERGLA is automated and uses a fast paradigm with skin electrodes.…”

Eletrorretinograma de padrão reverso macular e multifocal e tomografia de coerência óptica em olhos suspeitos de glaucoma e glaucomatosos com perda de hemicampo

“…Além disto, enquanto nossos pacientes com SG não diferiram significativamente dos controles no tempo de pico do PERGmf, nossos pacientes com GH apresentaram uma latência prolongada no hemicampo superior. Embora seja difícil entender completamente estas discrepâncias entre os nossos resultados e de estudos prévios, isto pode estar relacionado as diferentes definições de latência/fase (89) e diferentes idades dos pacientes estudados, já que é conhecido que a latência do PERG aumenta com a idade (93,112,113) . De qualquer forma, conforme observado por Bode et.…”