Clinical trial NCT02965924: Effect of Topical Phenylephrine 2.5% on EVP in Normal Human Eyes
Official title: Effect of Topical Phenylephrine 2.5% on Episcleral Venous Pressure in Normal Human Eyes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Assess Phenylephrine on EVP and IOP
Lead sponsor: Mayo Clinic
Sponsor class: OTHER
First posted: 2016-11-17
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: Phenylephrine hydrochloride ophthalmic solution is an alpha-1 adrenergic receptor agonist commonly used topically for dilation prior to ocular fundus examination. In the eye, phenylephrine acts locally as a potent vasoconstrictor and mydriatic by constricting ophthalmic blood vessels and the radial dilator muscle of the iris. Episcleral venous pressure (EVP) is a determinant of intraocular pressure (IOP) and can be measured non-invasively by venomanometry. Since phenylephrine is a vasoconstrictor, it may affect episcleral venous tone, but the effect on EVP is unknown. Understanding the physiology of episcleral veins helps us in better understanding of pathophysiology of glaucoma.


Eligibility criteria: Inclusion Criteria:

* Any self-declared ethno-racial category.
* Medically healthy subjects.
* Subjects with two healthy eyes.
* Intraocular pressure (IOP) less than 22 mmHg in each eye.
* Best-corrected visual acuity (BCVA) in each eye 20/50 or better.
* Open angles in both eyes.
* Contact lens wear stopped at least 3 days prior to study, and during the study.
* Ability to cooperate for examinations required for study.

Exclusion Criteria:

* Chronic or acute ophthalmic diseases including glaucoma, wet type macular degeneration, uveitis and clinically significant cataract.
* Evidence of ocular infection, inflammation, clinically significant blepharitis or conjunctivitis.
* Cornea pathologic changes preventing reliable measurement.
* Narrow anterior chamber angle.
* Previous intraocular surgeries, laser procedures, and intravitreal injections.
* Previous corneal refractive surgeries.
* Myopia greater than -6.00 D spherical equivalent.
* Hyperopia greater than +2.00 D spherical equivalent.
* Lack of suitable episcleral vein for measurement.
* Ocular trauma within the past 6 months.
* Ocular infection or ocular inflammation in the past 3 months.
* Ocular medication of any kind within 30 days of study visit.
* Known hypersensitivity to Phenylephrine or topical anesthetic medication.
* Severe hypertension: Systolic blood pressure greater than 180 mmHg and/or diastolic blood pressure greater than 105 mmHg.
* A known history of ischemic heart disease (angina or myocardial infarction), cerebrovascular accidents, cardiac arrhythmias, cerebral or aortic aneurysms.
* Uncontrolled diabetes mellitus.
* Uncontrolled hyperthyroidism.
* Use of some systemic medications within 30 days prior to study including: β-adrenergic antagonists, α-adrenergic agonists and antagonists, calcium channel blockers, diuretics, vasodilators, monoamine oxidase inhibitors, and systemic steroids.
* Participation in any interventional study within the past 30 days prior to study visit.
* Women who are pregnant.

Primary outcomes:
measure: Change in Episcleral Venous Pressure (EVP)
timeFrame: baseline, 60 minutes
Secondary outcomes:
measure: Change in Intraocular Pressure (IOP)
timeFrame: baseline, 60 minutes
Other outcomes:
Locations:
city: Rochester
country: United States
facility: Mayo Clinic in Rochester
state: Minnesota
Study officials:
affiliation: Mayo Clinic
name: Arthur J Sit, M.D.
role: PRINCIPAL_INVESTIGATOR
References: