Optimal timing of retinal scanning during dark adaptation, in the presence of fixation on a target: the role of pupil size dynamics.
J Biomed Opt
; 19(10): 106014, 2014.
Article
en En
| MEDLINE
| ID: mdl-25349032
While validating our newly developed vision screener based on a double-pass retinal scanning system, we noticed that in all patients the signals from the retina were significantly higher when measurements were performed within a certain time interval referenced to the initial moment when the lights were dimmed and the test subject was asked to fixate on a target. This appeared to be most likely attributable to pupil size dynamics and triggered the present study, whose aim was to assess the pupillary "lights-off" response while fixating on a target in the presence of an accommodative effort. We found that pupil size increases in the first 60 to 70 s after turning off the room lights, and then it decreases toward the baseline in an exponential decay. Our results suggest that there is an optimal time window during which pupil size is expected to be maximal, that is during the second minute after dimming the room lights. During this time, window retinal diagnostic instruments based on double-pass measurement technology should deliver an optimal signal-to-noise ratio. We also propose a mathematical model that can be used to approximate the behavior of the normalized pupil size.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Retina
/
Pupila
/
Adaptación a la Oscuridad
/
Fijación Ocular
Límite:
Adult
/
Humans
/
Middle aged
Idioma:
En
Revista:
J Biomed Opt
Asunto de la revista:
ENGENHARIA BIOMEDICA
/
OFTALMOLOGIA
Año:
2014
Tipo del documento:
Article
Pais de publicación:
Estados Unidos