Abstract
Purpose :
To study the accommodative dynamics for predictable and unpredictable stimuli using
manual and automated accommodative facility tests
Methods :
Seventeen young healthy subjects (mean age 23 ± 2 years) were tested monocularly in
two consecutive sessions, using five different conditions in each session. Two
conditions replicated the conventional monocular accommodative facility tests for far
and near distances, performed with manually held flippers. The other three conditions
were automated and conducted using an electro-optical system and open-field
autorefractor. Two of the three automated conditions replicated the predictable manual
accommodative facility tests. The last automated condition was a hybrid approach
using a novel method whereby far and near accommodative facility tests were
randomly integrated into a single test of four unpredictable accommodative demands
Results :
The within-subject standard deviations for far and near distance were (±1,±1) cpm for
the manual flipper accommodative facility conditions and (±3, ±4) cpm for the
automated conditions. The 95% limits of agreement between the manual and the
automated conditions for far and near distances were poor: (-18, 12) and (-15, 3).
During the hybrid unpredictable condition, the response time and accommodative
response parameters were significantly (p<0.05) larger for accommodation than
disaccommodation responses for high accommodative demands only. The response
times during the transitions 0.17/2.17 D and 0.50/4.50 D were not significantly different
between the hybrid unpredictable and the conventional predictable automated tests
Conclusions :
The automated accommodative facility test does not agree well with the manual flipper
test results, for either far or near distances. It is likely that operator delays in flipping the
lens account for these differences. The novel hybrid test using an unpredictable
accommodation demand level provides a more comprehensive examination of the
accommodative dynamics than the conventional manual accommodative facility tests.
Unexpectedly, the unpredictability of the stimulus did not to affect accommodation
dynamics
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.