Effect of Ambient Light on the Parameters of the Pupillary Light Reflex

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT01207817

Enrollment

Registered

2010-09-23

Start date

2009-09-30

Completion date

2010-02-28

Last updated

2010-09-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy Volunteers

Keywords

a light flash in each eye for a total of 48 measurements

Brief summary

The purpose of this study is to determine the effects of varying luminescent levels on the pupillary response.

Detailed description

Evaluation of the pupillary response is an underemphasized aspect of the assessment of visual function. The pupillary light reflex is one of the few objective indicators of afferent input from the retina and optic nerve. Since the pupillary light reflex is processed through the retina, it may be used to assess visual integrity (1). Pupillometry is a reliable technology capable of providing repetitive data on quantitative pupillary function in states of health and disease (2). Amplitude, latency, maximum constriction velocity, mean constriction velocity, and dilation velocity are measured using the Neuroleptics pupillometer. The effects of varying levels of ambient light on these parameters of the pupillary response have not been extensively studied. The purpose of this investigation is to determine the effects of varying luminescent levels on the pupillary response.

Interventions

OTHERPupillometry

Pupillometry readings will be taken at low, intermediate and high ambient light

Study design

Observational model

CASE_CONTROL

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Yes

Inclusion criteria

* healthy volunteers

Exclusion criteria

* recent bout of conjunctivitis or infection in the eye recent eye surgery seizure disorder unable to lie flat for 30 minutes known history of eye disease which cannot be corrected with lenses

Design outcomes

Primary

Measure	Time frame
pupillary light reflex: amplitude, latency, maximum constriction velocity, mean constriction velocity and dilation velocity during different levels of ambient light	Pupillometry readings will be taken at 3 potential light readings low light, intermediate light and high ambient light. A total of 48 readings will be done. All parameters will be done at one sitting and will take approximately 45 minutes to complete.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026