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Choroidal Blood Flow Changes During Dark/Light Transitions in Patients With Insulin-dependent Diabetes Mellitus (IDDM)

This study has been terminated.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00718614
First Posted: July 18, 2008
Last Update Posted: November 25, 2014
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Gerhard Garhofer, Medical University of Vienna
  Purpose
There is evidence from a variety of animal studies that choroidal blood flow is under neural control. Recent results in humans indicate that a light/dark transition is associated with a short lasting reduction in choroidal blood flow. Several observations indicate that the changes in choroidal perfusion are triggered at least in part by neural mechanisms. Particularly, we have shown that during unilateral dark/light transition both eyes react with choroidal vasoconstriction strongly indicating a neural mechanism for blood flow regulation. Investigation of changes in choroidal blood flow during light/dark transition may represent an interesting approach to study neural dysregulation at the level of the eye in patients with IDDM. Accordingly, the hypothesis of reduced choroidal blood flow responses to a light/dark transition in patient with IDDM will be tested. This response in choroidal blood flow will be correlated to parameters of diabetic neuropathy and diabetic retinopathy.

Condition Intervention
Diabetes Mellitus, Type 1 Diabetic Retinopathy Procedure: Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Choroidal Blood Flow Changes During Dark/Light Transitions in Patients With IDDM

Resource links provided by NLM:


Further study details as provided by Gerhard Garhofer, Medical University of Vienna:

Primary Outcome Measures:
  • fundus pulsation amplitude [ Time Frame: 3 hours ]
  • choroidal blood flow [ Time Frame: 3 hours ]

Secondary Outcome Measures:
  • Nerve conduction velocity [ Time Frame: measured before intervention ]
  • Pupil diameter during infra-red pupillometry [ Time Frame: measured before intervention ]
  • heart rate variability [ Time Frame: measured before intervention ]

Estimated Enrollment: 80
Study Start Date: June 2007
Study Completion Date: July 2007
Primary Completion Date: July 2007 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
1
Patients with long standing IDDM (>10 years) and no diabetic retinopathy
Procedure: Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
2
Patients with long standing IDDM (>10 years) and mild non-proliferative diabetic retinopathy
Procedure: Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
3
Patients with long standing IDDM (>10 years) and moderate to severe non-proliferative diabetic retinopathy
Procedure: Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
4
healthy volunteers, matched for age and sex
Procedure: Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.
Light will be switched from 0.5µW/cm2/sr to 115µW/cm2/sr.

  Eligibility

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Ages Eligible for Study:   19 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

For healthy control subjects:

  • Men and women aged over 18 years, matched in regard to age, sex and smoking status
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant
  • Normal ophthalmic findings, Ametropia < 3 dpt for healthy control subjects

For patients with IDDM:

  • Men and women aged over 18 years
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • Long standing IDDM > 10 years
  • Mild or moderate to severe non-proliferative diabetic retinopathy (defined according to the MAHC)
  • Ametropia < 3 dpt

Exclusion Criteria:

Any of the following will exclude a healthy subject from the study:

  • Regular use of vasoactive medication with may interfere with the study procedure, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • Blood donation during the previous 3 weeks

Any of the following will exclude a patient with IDDM from the study:

  • Evidence of any relevant retinal or choroidal disease (Glaucoma, age related macula degeneration, cataract, history of central retinal artery obstruction or central retinal vein thrombosis)
  • Ophthalmological surgery (history of photo laser coagulation, including argon laser trabeculoplasty (ALT), trabeculectomy, deep sclerectomy)
  • History of intravitreal injection with anti-proliferative therapy
  • Need for dialysis
  • Non-treated systemic hypertension (SPB>150, DBP>95)
  • Evidence of coronary heart disease, cardiomyopathy, stenocardia, congestive heart failure, peripheral occlusive vascular disease, cardiac autonomic neuropathy
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • Blood donation during the previous 3 weeks
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00718614


Locations
Austria
Department of Clinical Pharmacology
Vienna, Austria, 1090
Sponsors and Collaborators
Medical University of Vienna
Investigators
Principal Investigator: Gerhard Garhoefer, MD Department of Clinical Pharmacology, Medical University of Vienna
  More Information

Responsible Party: Gerhard Garhofer, Assoc. Prof. Priv. - Doz. Dr, Medical University of Vienna
ClinicalTrials.gov Identifier: NCT00718614     History of Changes
Other Study ID Numbers: OPHT-300505-2
First Submitted: July 7, 2008
First Posted: July 18, 2008
Last Update Posted: November 25, 2014
Last Verified: November 2014

Keywords provided by Gerhard Garhofer, Medical University of Vienna:
Choroidal blood flow
Laser Doppler flowmetry
Diabetic Retinopathy
Diabetic Neuropathy

Additional relevant MeSH terms:
Diabetes Mellitus
Retinal Diseases
Diabetic Retinopathy
Diabetes Mellitus, Type 1
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Eye Diseases
Diabetic Angiopathies
Vascular Diseases
Cardiovascular Diseases
Diabetes Complications
Autoimmune Diseases
Immune System Diseases