Electrophysiological testing of visual function after mirror telescope implantation: a case report
The implantation of an intraocular telescope increases life quality in patients with end-stage age-related macular degeneration (AMD). The present study monitored changes in electrophysiological markers of visual processing before and during seventeen months after a novel mirror telescope implantation in two patients (OV—male 90 years, MZ—female 70 years) with the final-stage form of AMD.
Visual evoked potentials were recorded to high-contrast pattern-reversal (PR-VEP for check size 40′ and 10′), low-contrast motion-onset stimuli (in visual periphery M-VEP M20°, and in central part M-VEP C8°), and event-related potentials (ERPs) in the oddball visual paradigm.
MZ’s more systematic responses showed attenuation and prolongation of the M-VEP M20° and the PR-VEP 40′ immediately after the telescope implantation with a slow amplitude recovery with unchanged prolonged latency. The implantation completely eradicated the M-VEP C8° without any restoration. The PR-VEP 10′ were not readable. Only a part of OV’s PR-VEP 40′ and M-VEP M20′ were of a repeatable and expected morphology. These OV’s VEPs were consistent with MZ’s findings. The ERPs did not show any effect of implantation in both patients. Post-implantation visual acuity and reaction time overcame the pre-implantation levels.
The mirror telescope preserved peripheral vision in contrast to classic telescopes; however, the telescope concurrently reduced the luminance of the magnified retinal image, which was likely responsible for the prolongation of the VEP latencies.
KeywordsIntraocular mirror telescope Age-related macular degeneration Motion-onset VEPs Pattern-reversal VEPs Oddball ERPs P3b
Lipshitz macular implant—intraocular mirror telescope OriLens
Age-related macular degeneration
Visual evoked potential
- PR-VEP 40′
PR-VEP evoked by checkerboard of 40′ checks
- PR-VEP 10′
PR-VEP evoked by checkerboard of 10′ checks
- M-VEP C8°
M-VEP evoked by central 8° stimulus
- M-VEP M20°
M-VEP evoked by peripheral stimulus outside central 20°
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