Wearing-Off Period of Pharmacological Dilation and Anisocoria

Study Overview
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Brief Summary
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Students at the School of Medicine Greenville will be asked to participate in this study. The aim of this study is to better understand when medical imaging is needed for patients with anisocoria (unequal pupil size). Participation in the study includes up to 3 visits over a period of one week. Each study visit will last about 30 minutes. At the first visit, participants will be screened for hyperopia using a phoropter, have their intraocular pressures taken using a tono-pen, and have their iridocorneal angle measured using gonioscopy at the ophthalmology clinic. Proparacaine hydrochloride 0.5% eye drops will be used to numb the eyes before measuring intraocular pressures and prior to gonio lens exam. Participants will also be asked to complete three forms. Participants will be asked to return to the clinic on a scheduled day within one week of the screening visit to have their left eye dilated. At this visit, the diameter of the pupil will be measured using a Near card in a windowless room with a set light-level. Then, the participant will receive one drop of tropicamide in the left eye. After the drops have had time to take effect, which will be about 20-30 minutes later, the diameter of the pupil will be measured again. Participants will then be asked to return to the clinic in 3-4 hours. At this time, the diameter of the pupil will be measured again. The third type of eye drop used in this study is 1% pilocarpine. 1 % pilocarpine will briefly constrict the eyes. One drop of 1% pilocarpine will be administered to left eye, and the change in pupillary diameter will be measured, if any. It will take about 10-15 minutes for the 1% pilocarpine to take effect. Participants may be required to attend 2 additional 30-minute visits on a third day depending on how their eyes respond to the drops. This study will recruit about 10-15 participants.

Official Title
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The Wearing-Off Period of Pharmacological Dilation: An Addendum to the Management of Anisocoria

Conditions
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Anisocoria

Intervention / Treatment
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* Drug: Tropicamide
* Drug: 1% Pilocarpine
* Drug: Proparacaine Hydrochloride
* Device: Tono pen AVIA
* Device: VG4 Gonio
* Device: Reichert phoropter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Student at the University of South Carolina School of Medicine Greenville Healthy participants No significant ophthalmological history Exclusion Criteria: a history of angle closure glaucoma, any other type of glaucoma any elevated eye pressure readings any history of intraocular surgery or procedure. if the participant is found to be hyperopic to >+1 diopter, has an intraocular pressure of > 22 mm Hg in either eye, or displays an iridocorneal angle where trabecular meshwork known allergy to natural rubber latex

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Eye Dilation and Constriction<br>Participants screened for hyperopia >+1 diopter using a phoropter, have their intraocular pressures measured using a tono pen, and have their iridocorneal angle measured with a gonio lens. Proparacaine hydrochloride 0.5% eye drops will be used to numb the eyes before measuring intraocular pressures and prior to gonio lens. The following day, the participant will receive one drop of tropicamide and one drop of 1% pilocarpine in the left eye. If the left eye has no response to the 1% pilocarpine, or if the diameter of the pupil returned to baseline size, we will ask participants to come back to the clinic on another day to have the process repeated in the right eye. | Drug: Tropicamide<br>* One drop will be given to participants<br>Drug: 1% Pilocarpine<br>* One drop will be given to participants<br>Drug: Proparacaine Hydrochloride<br>* One drop will be given to participants<br>Device: Tono pen AVIA<br>* Participant intraocular pressures measured<br>Device: VG4 Gonio<br>* Participant iridocorneal angle measured<br>Device: Reichert phoropter<br>* Participant screened for hyperopia >+1 diopter<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Constricting Response to Pilocarpine 1% in the Pharmacologically Dilated Eye | Measurement of pupil diameter | 4 hours |