Clinical Ophthalmology (Jul 2017)
Visual processing in patients with age-related macular degeneration performing a face detection test
Abstract
Pasi Vottonen,1 Kai Kaarniranta,1,2 Ari Pääkkönen,3 Ina M Tarkka4 1Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland; 2Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; 3Department of Clinical Neurophysiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; 4Department of Health Sciences, University of Jyväskylä, Jyväskylä, Finland Purpose: People with age-related macular degeneration (AMD) have difficulties in familiar face recognition and facial expression discrimination. Our aim was to evaluate the visual processing of faces in AMD patients and whether this would be improved by anti-vascular endothelial growth factor therapy. This was a prospective interventional cohort study. Patients: Twelve patients with monocular wet AMD and 6 control subjects were recruited. Face detection processes were studied using cortical event-related potentials (ERPs). Patients received 3 bevacizumab intravitreal injections to the single affected eye. At baseline and 4–6 weeks after the last injection, clinical presentation and ERPs of the face task were evaluated. Face pictures were shown as targets (16.7%) among standard pictures of pixelated faces in an oddball-type paradigm. Results: Face pictures elicited well-defined electrical components in occipital and parieto-occipital cortical areas at baseline and after treatment. The face-specific N170 component was evident in all subjects with longer peak latency in patients than in controls (170±13 vs 155±14, P=0.032). Unexpectedly, an early component reflecting unintentional prediction of perceiving a face, that is, deviance-related negativity, was present in patients and controls. Visual acuity of the affected eye seemed improved in patients from logarithm of the minimum angle of resolution 0.71 (±0.33) to 0.52 (±0.39) by 119 (±23) days without accompanying significant change in face-specific ERPs. Conclusions: Monocular wet AMD distinctly influenced face-specific brain electrophysiological components. However, the anti-vascular endothelial growth factor treatment did not improve the binocular face detection ability. The EudraCT number of this study is 2012-000765-20. Keywords: age-related eye diseases, bevacizumab, face recognition, EEG, N170
