Document Detail

Static and dynamic accommodation measured using the WAM-5500 Autorefractor.
MedLine Citation:
PMID:  20852450     Owner:  NLM     Status:  MEDLINE    
PURPOSE: This study was undertaken to compare static and dynamic accommodation measurements using the Grand Seiko WR-5500 (WAM) in young, phakic subjects.
METHODS: Fifteen subjects, aged 20 to 28 years (23.8 ± 0.58 years; mean ± SD years) participated. Accommodation was stimulated with printed text presented at various distances. In static mode, three measurements were taken for each stimulus amplitude. In dynamic mode, 5-Hz recordings were started, and subjects alternately looked through a transparent near chart and focused on a letter chart at 6 m for 5 seconds and then focused on the near letter chart for 5 seconds for a total of 30 seconds. After smoothing the raw data, the highest three individual values recorded in each 5-s interval of focusing at near were averaged for each stimulus amplitude. Analysis of variance and Bland-Altman analysis were used to compare the static and dynamic measurements. A calibration was performed with +3.00 to -10.00 D trial lenses behind an infrared filter, in 1.00 D steps in 5 of the 15 subjects.
RESULTS: Stimulus-response graphs from static and dynamic modes were not significantly different in the lower stimulus range (<5.00 D, p = 0.93), but differed significantly for the higher stimulus amplitudes (p = 0.0027). One of the 15 subjects showed a significant difference between the static and dynamic modes. Corresponding pupil diameter could be recorded along with the accommodation responses for the subjects, and pupil diameter decreased with increasing stimulus demand. Calibration curves for static and dynamic measurements were not significantly different from the 1:1 line or from each other (p = 0.32).
CONCLUSIONS: Slight differences between the dynamically and statically recorded response amplitudes were identified. This is attributed to differences in the accommodative responses in this population and not to the instrument performance. Dynamic measurement of accommodation and pupil constriction potentially provides additional useful information on the accommodative response other than simply the response amplitude.
Dorothy M Win-Hall; Jamie Houser; Adrian Glasser
Publication Detail:
Type:  Comparative Study; Evaluation Studies; Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Optometry and vision science : official publication of the American Academy of Optometry     Volume:  87     ISSN:  1538-9235     ISO Abbreviation:  Optom Vis Sci     Publication Date:  2010 Nov 
Date Detail:
Created Date:  2010-11-03     Completed Date:  2011-03-02     Revised Date:  2013-05-27    
Medline Journal Info:
Nlm Unique ID:  8904931     Medline TA:  Optom Vis Sci     Country:  United States    
Other Details:
Languages:  eng     Pagination:  873-82     Citation Subset:  IM    
College of Optometry, University of Houston, Houston, Texas 77204-2020, USA.
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MeSH Terms
Accommodation, Ocular*
Analysis of Variance
Equipment Design
Linear Models
Models, Biological
Vision Tests / instrumentation*,  methods*
Young Adult
Grant Support
1 R01 EY017076/EY/NEI NIH HHS; P30 EY007551/EY/NEI NIH HHS; P30 EY007551/EY/NEI NIH HHS; T35 EY007088/EY/NEI NIH HHS

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