Intraocular Pharmacokinetics of Erythropoietin After Single Intravitreal Injection in Human

Study Overview
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Brief Summary
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The investigators investigate intraocular concentrations and pharmacokinetics of erythropoietin after a single intravitreal injection in humans.

Detailed Description
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Intravitreal injections of erythropoietin for off-label use have been shown to be beneficial in eyes with diabetic macular edema.However, the pharmacokinetic profile of erythropoietin after intravitreal injection in humans has not yet been determined clearly. The purpose of this study was to determine the intraocular pharmacokinetics of erythropoietin after a single intravitreal injection in a prospective investigation.

Official Title
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Intraocular Pharmacokinetics of Erythropoietin After Single Intravitreal Injection in Human

Conditions
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Pharmacokinetics, Erythropoietin

Intervention / Treatment
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* Procedure: Vitrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: diabetic macular edema that failed to respond to or recurred after the previous macular focal laser photocoagulation or intravitreal therapy, or both. visual acuity worse than 40/200 snellen bisual acuity Exclusion Criteria: Eyes with vitreomacular traction, active proliferative diabetic retinopathy, intraocular inflammation, uncontrolled intraocular pressure , cataract surgery within the past six months, or a prior history of vitreoretinal surgery

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Erythropoietin<br>patients with chronic macular edema associated with diabetic retinopathy | Procedure: Vitrectomy<br>* vitrectomy following intravitreal erythropoietin<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration of erythropoietin in aqueous humor | erythropoietin injections had been performed in our department following standard procedures. In selected cases,vitrectomy was performed one to two days after erythropoietin injection to treat diabetic macular edema.During surgery, aqueous humor samples were obtained via a corneal paracentesis anterior to the limbus at the beginning of the procedure. | a few seconds | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration of erythropoietin in vitreous | erythropoietin injections had been performed in our department following standard procedures. In selected cases,vitrectomy was performed one to two days after erythropoietin injection to treat diabetic macular edema.During surgery, vitreous samples were obtained via vitreous cutter at the beginning of the procedure. | few minutes |