Electrophysiological testing of visual function after mirror telescope implantation: a case report.
OBJECTIVE
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Department of Pathological Physiology, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 38, Hradec Králové, Czech Republic. jan.kremlacek@lfhk.cuni.cz.
Jan
http://orcid.org/0000-0001-8641-4287
J
Kremláček
Department of Ophthalmology, Faculty of Medicine in Hradec Králové, University Hospital and Charles University, Prague, Czech Republic.
Naďa
N
Jirásková
Department of Ophthalmology, Faculty of Medicine in Hradec Králové, University Hospital and Charles University, Prague, Czech Republic.
Jana
J
Nekolová
Institute of Psychology, Academy of Sciences, Brno, Czech Republic.
Radovan
R
Šikl
Department of Pathological Physiology, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 500 38, Hradec Králové, Czech Republic.
Miroslav
M
Kuba
D000368:Aged; D000369:Aged, 80 and over; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D007909:Lenses; D008268:Macular Degeneration / Q000503:physiopathology / Q000534:rehabilitation; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology; D061351:Telescopes; D014792:Visual Acuity; D014796:Visual Perception / Q000502:physiology*; D057488:Visual Prosthesis / Q000592:standards
Age-related macular degeneration; Intraocular mirror telescope; Motion-onset VEPs; Oddball ERPs; P3b; Pattern-reversal VEPs