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Comparison of Different Refraction Measurements in Adults

Comparison of Different Refraction Measurements in Adults

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04434521
Acronym
REFRACT
Enrollment
17
Registered
2020-06-17
Start date
2021-03-05
Completion date
2021-05-03
Last updated
2022-09-13

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

Conditions

Vision Loss Night

Brief summary

The combatant is likely to carry out missions any time, any place, day or night. The very strong degradation of natural vision performance in these conditions justifies the use of visual replacement means, based on optronic sensors whose sensitivity is more adapted to these luminous environments than that of the human eye. The duration and repetition of missions carried out with night vision sensors lead to visual complaints from users. The literature on night vision binoculars adjustment states that a binocular adjustment of the equipment provides more convex settings. The latter would then limit the strain on the accommodative component, which is one of the possible sources of operator visual fatigue. In order to allow a more appropriate adjustment, it is proposed to rely on a measurement of the refraction (optical defect of the eye) of each operator. Like binocular adjustments, binocular refractive methods would limit accommodative stimulation and thus visual fatigue. However, these methods are little used in favour of conventional methods. It is therefore necessary to evaluate the interest of binocular refraction for the adjustment of night vision binoculars. The purpose of this study is to compare refraction measurements by procedure in adult subjects free of ophthalmological disorders.

Interventions

BEHAVIORALQuestionnaire

Questionnaire about habits in terms of near vision activities

The eye examination involves the following measurements: * Distant vision phoria with Thorington method * Close vision with Thorington method * Objective eye-to-eye refraction with self-refractometer * Binocular objective refraction with autorefractometer * Monocular/biocular/binocular refraction with Nidek TS610 * SiView automatic refraction * Humphriss binocular refraction * MOU Binocular refraction

Sponsors

Direction Centrale du Service de Santé des Armées
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Age over 18 ; * Non-presbyopic subject; * Stereoscopic acuity ≤ 60 arc seconds.

Exclusion criteria

* Accommodative insufficiency; * Accommodative inertia; * Compensation by orthokeratology (i.e. night lenses); * Present or past binocular pathology (strabismus or amblyopia); * Pregnant or nursing woman; * Incomprehension of French (written and spoken).

Design outcomes

Primary

MeasureTime frameDescription
Maximum convex equivalent sphere valuesAt visit 1 (day 1)Maximum convex equivalent sphere values obtained by the different refraction procedures under study.

Secondary

MeasureTime frameDescription
High contrast monocular acuity valuesAt visit 1 (day 1)High contrast monocular acuity values obtained by the different refraction procedures.
Low contrast monocular acuity valuesAt visit 1 (day 1)Low contrast monocular acuity values obtained by the different refraction procedures.
High contrast binocular acuity valuesAt visit 1 (day 1)High contrast binocular acuity values obtained by the different refraction procedures.
Low contrast binocular acuity valuesAt visit 1 (day 1)Low contrast binocular acuity values obtained by the different refraction procedures.
Difference between binocular perceptual assessment scores before and after subjective adjustmentDifference between visit 1 (day 1) and visit 2Difference between binocular perceptual assessment scores obtained by the different refractive procedures before and after subjective adjustment. Binocular perceptual assessment score will be obtained using visual analogue faces. The score will range from excellent comfort to unbearable.

Countries

France

Outcome results

None listed

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