Diameter Changes of Retinal Vessels During Hypoxia

Sponsor

University of Aarhus (Other)

Overall Status

Completed

CT.gov ID

NCT01689090

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

1.5

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The primary objective is to study if an inhibition of nitric oxide and/or prostaglandins affect the diameter changes of retinal vessels observed during hypoxia. Diameter changes are studied using the Dynamic Vessel Analyzer.

Condition or Disease	Intervention/Treatment	Phase
Diabetes Mellitus Type 1 Diabetic Maculopathy	Other: COX inhibitor Other: L-NG-monomethyl arginine citrate Other: COX inhibitor + L-NG-monomethyl arginine citrate	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

58 participants

Allocation:

Non-Randomized

Intervention Model:

Crossover Assignment

Masking:

None (Open Label)

Primary Purpose:

Basic Science

Official Title:

Diameter Changes of Retinal Vessels During Hypoxia

Study Start Date :

Nov 1, 2012

Actual Primary Completion Date :

Mar 1, 2016

Actual Study Completion Date :

Mar 1, 2016

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Hypoxia Inhaling hypoxic gas mixture to induce hypoxemia during recordings of diameter changes of retinal vessels. Recording are performed during hypoxia alone and in combination with the associated interventions at two examination days.	Other: COX inhibitor Administration of 1 drop voltaren 45 minutes before recordings of diameter changes of retinal vessels are initiated Other Names: Eye drops voltaren 1 mg/ml Other: L-NG-monomethyl arginine citrate Intravenous administration of L-NMMA during recordings of diameter changes of retinal vessels Other Names: L-NMMA Other: COX inhibitor + L-NG-monomethyl arginine citrate Combination of interventions. Administration of an eye drop voltaren and 45 minutes later infusion with L-NMMA is started and recording of diameter changes of retinal vessels is performed
Experimental: Normoxia Breathing atmospheric air during recordings of diameter changes of retinal vessels. Recording are performed during normoxia alone and in combination with the associated interventions at two examination days.	Other: COX inhibitor Administration of 1 drop voltaren 45 minutes before recordings of diameter changes of retinal vessels are initiated Other Names: Eye drops voltaren 1 mg/ml Other: L-NG-monomethyl arginine citrate Intravenous administration of L-NMMA during recordings of diameter changes of retinal vessels Other Names: L-NMMA Other: COX inhibitor + L-NG-monomethyl arginine citrate Combination of interventions. Administration of an eye drop voltaren and 45 minutes later infusion with L-NMMA is started and recording of diameter changes of retinal vessels is performed

Arm

Intervention/Treatment

Experimental: Hypoxia

Inhaling hypoxic gas mixture to induce hypoxemia during recordings of diameter changes of retinal vessels. Recording are performed during hypoxia alone and in combination with the associated interventions at two examination days.

Other: COX inhibitor

Administration of 1 drop voltaren 45 minutes before recordings of diameter changes of retinal vessels are initiated

Other Names:

Eye drops voltaren 1 mg/ml

Other: L-NG-monomethyl arginine citrate

Intravenous administration of L-NMMA during recordings of diameter changes of retinal vessels

Other Names:

L-NMMA

Other: COX inhibitor + L-NG-monomethyl arginine citrate

Combination of interventions. Administration of an eye drop voltaren and 45 minutes later infusion with L-NMMA is started and recording of diameter changes of retinal vessels is performed

Experimental: Normoxia

Breathing atmospheric air during recordings of diameter changes of retinal vessels. Recording are performed during normoxia alone and in combination with the associated interventions at two examination days.

Other: COX inhibitor

Administration of 1 drop voltaren 45 minutes before recordings of diameter changes of retinal vessels are initiated

Other Names:

Eye drops voltaren 1 mg/ml

Other: L-NG-monomethyl arginine citrate

Intravenous administration of L-NMMA during recordings of diameter changes of retinal vessels

Other Names:

L-NMMA

Other: COX inhibitor + L-NG-monomethyl arginine citrate

Combination of interventions. Administration of an eye drop voltaren and 45 minutes later infusion with L-NMMA is started and recording of diameter changes of retinal vessels is performed

Outcome Measures

Primary Outcome Measures

Diameter changes of retinal vessels [Examination day 1 and 2]
Comparing the differences of diameter changes occuring during each of the interventions.

Eligibility Criteria

Criteria

Ages Eligible for Study:

20 Years to 65 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Diabetes type 1 without retinopathy
Diabetic retinopathy

Exclusion Criteria:

Cardio-vascular disease
Lung disease
Pregnancy
Previous ocular disease other than retinal branch vein occlusion
Previous treatment with medications influencing on the intraocular pressure or the metabolism of nitric oxide or prostaglandins