Unusual Visual Evoked Potentials in Patients with Age-Related Macular Degeneration

2000 ◽  
Vol 214 (5) ◽  
pp. 312-319 ◽  
Author(s):  
Peter Walter ◽  
Pia Königsfeld ◽  
Ferrial Soudavar ◽  
Richard Brunner
Eye and Brain ◽  
2021 ◽  
Vol Volume 13 ◽  
pp. 111-127
Author(s):  
Craig Versek ◽  
S Mohammad Ali Banijamali ◽  
Peter Bex ◽  
Kameran Lashkari ◽  
Sagar Kamarthi ◽  
...  

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tommaso Verdina ◽  
Stefania Piaggi ◽  
Vanessa Ferraro ◽  
Valeria Russolillo ◽  
Riccardo Peschiera ◽  
...  

AbstractAge-related macular degeneration (AMD) is a progressive and degenerative disorder of the macula. In advanced stages, it is characterized by the formation of areas of geographic atrophy or fibrous scars in the central macula, which determines irreversible loss of central vision. These patients can benefit from visual rehabilitation programmes with acoustic “biofeedback” mechanisms that can instruct the patient to move fixation from the central degenerated macular area to an adjacent healthy area, with a reorganization of the primary visual cortex. In this prospective, comparative, non-randomized study we evaluated the efficacy of visual rehabilitation with an innovative acoustic biofeedback training system based on visual evoked potentials (VEP) real-time examination (Retimax Vision Trainer, CSO, Florence), in a series of patients with advanced AMD compared to a control group. Patients undergoing training were subjected to ten consecutive visual training sessions of 10 min each, performed twice a week. Patients in the control group did not receive any training. VEP biofeedback rehabilitation seems to improve visual acuity, reading performances, contrast sensitivity, retinal fixation and sensitivity and quality of life in AMD patients.


2020 ◽  
Author(s):  
Craig Versek ◽  
S. Mohammad Ali Banijamali ◽  
Peter J. Bex ◽  
Kameran Lashkari ◽  
Sagar V. Kamarthi ◽  
...  

AbstractDelayed Dark Adapted vision Recovery (DAR) is a biomarker for Age-related Macular Degeneration (AMD); however, its measurement is burdensome for patients and examiners. We developed a portable, wireless, quick-setup system that employs a headset with a smartphone to deliver and analyze controlled dichoptic photobleach and pattern reversal stimuli, and with custom electroencephalography (EEG) electrodes, to measure objective Dark Adapted Visual Evoked Potentials (DAVEP) at multiple locations of the visual field in one comfortable 20-minute session, without requiring subject reporting. DAVEP responses post photobleach (up to 15 minutes), were measured concurrently in both eyes of 13 patients with AMD and 8 others not diagnosed with AMD. New unexpected features were observed in the DAVEP responses at high latencies to scotopic stimulus intensities. The amplitude recovery of the DAVEP response was significantly delayed in AMD patients compared with controls. We developed DAVEP1 scores, a simple metric for DAR, using it to successfully identify all 100% of AMD subjects and correctly classify 90% of subject eyes. Deficits in DAR in patients with AMD can be identified with this objective VEP based system using the DAVEP1 metric, a promising new objective biomarker for this disease that can be easily tested in a clinic.


Author(s):  
T. Babenko ◽  
◽  
K. Loganovsky ◽  
T. Loganovska ◽  
N. Medvedovska ◽  
...  

One of the current problems of modern radiobiology is determine the characteristics of the manifestation of radiation-induced effects not only at different dose loads, but also at different stages of development of the organism. In previous reports, we have summarized available evidence that at certain ages there is a comparative acceleration of radiation-induced pathological changes in the eye and brain, and the study and assessment of the risk of possible ophthalmic and neurological pathology in remote periods after contamination of radioactive areas. Data of irradiated in utero individuals are possible on the basis of observation of the state of the visual analyzer in persons who underwent intrauterine irradiation in 1986. Therefore, a parallel study of retinal morphometric parameters, amplitude and latency of components of evoked visual potentials in irradiated in utero individuals was performed. Objective: to evaluate the retinal morphometric parameters, amplitude and latency components of the evoked visual potentials in intrauterine irradiated persons. Materials and methods. The results of surveys of 16 people irradiated in utero in the aftermath of the Chornobyl disaster were used; the comparison group were residents of Kyiv of the corresponding age (25 people). Optical coherence tomography was performed on a Cirrus HD-OCT, Macular Cube 512x128 study technique was used. At the same time, the study of visual evoked potentials on the inverted pattern was performed, and occipital leads were analyzed. Visual evoked potentials were recorded on a reversible chess pattern (VEP) – an electrophysiological test, which is a visual response to a sharp change in image contrast when presenting a reversible image of a chessboard. Results. In those irradiated in utero at the age of 22–25 years, there was a probable increase in retinal thickness in the fovea, there was a tendency to increase the thickness of the retina in the areas around the fovea. When recording visual evoked potentials on a reversible chess pattern in this group, there was a tendency to decrease the amplitudes of components (N75, P100, N145, P200) in the right and left parieto-occipital areas and asymmetric changes in latency of these components. Conclusions. Early changes of fovea recorded in OCT and decreasing amplitudes of components of visual evoked potentials on the reversible chess pattern at the age of 22–25 years may indicate a risk of development in patients irradiated in utero, early age-related macular degeneration, as well as increased risk and increased risk structures of the visual analyzer. Key words: induced visual potentials, optical coherence tomography, retina, agerelated macular degeneration, ion izing radiation, dose.


Sign in / Sign up

Export Citation Format

Share Document