Face recognition in age related macular degeneration: perceived disability, measured disability, and performance with a bioptic device.
OBJECTIVE
(1) To explore the relation between performance on tasks of familiar face recognition (FFR) and face expression difference discrimination (FED) with both perceived disability in face recognition and clinical measures of visual function in subjects with age related macular degeneration (AMD). (2) To quantify the gain in performance for face recognition tasks when subjects use a bioptic telescopic low vision device.


METHODS
30 subjects with AMD (age range 66-90 years; visual acuity 0.4-1.4 logMAR) were recruited for the study. Perceived (self rated) disability in face recognition was assessed by an eight item questionnaire covering a range of issues relating to face recognition. Visual functions measured were distance visual acuity (ETDRS logMAR charts), continuous text reading acuity (MNRead charts), contrast sensitivity (Pelli-Robson chart), and colour vision (large panel D-15). In the FFR task, images of famous people had to be identified. FED was assessed by a forced choice test where subjects had to decide which one of four images showed a different facial expression. These tasks were repeated with subjects using a bioptic device.


RESULTS
Overall perceived disability in face recognition did not correlate with performance on either task, although a specific item on difficulty recognising familiar faces did correlate with FFR (r = 0.49, p<0.05). FFR performance was most closely related to distance acuity (r = -0.69, p<0.001), while FED performance was most closely related to continuous text reading acuity (r = -0.79, p<0.001). In multiple regression, neither contrast sensitivity nor colour vision significantly increased the explained variance. When using a bioptic telescope, FFR performance improved in 86% of subjects (median gain = 49%; p<0.001), while FED performance increased in 79% of subjects (median gain = 50%; p<0.01).


CONCLUSIONS
Distance and reading visual acuity are closely associated with measured task performance in FFR and FED. A bioptic low vision device can offer a significant improvement in performance for face recognition tasks, and may be useful in reducing the handicap associated with this disability. There is, however, little evidence for a correlation between self rated difficulty in face recognition and measured performance for either task. Further work is needed to explore the complex relation between the perception of disability and measured performance.
Tejeria
L
L
Research Group in Eye and Vision Science, Manchester Royal Eye Hospital, University of Manchester, Oxford Road, UK.
Harper
R A
RA
Artes
P H
PH
Dickinson
C M
CM
D000368:Aged; D000369:Aged, 80 and over; D005149:Facial Expression; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000150:complications* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D055095:Optics and Photonics / Q000295:instrumentation*; D020238:Prosopagnosia / Q000150:complications* / Q000503:physiopathology / Q000523:psychology; D012647:Self-Assessment; D014787:Vision Tests; D015348:Vision, Binocular; D014792:Visual Acuity