<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT01721811</url>
  </required_header>
  <id_info>
    <org_study_id>Klefter2</org_study_id>
    <nct_id>NCT01721811</nct_id>
  </id_info>
  <brief_title>Retinal Function in Relation to Transient or Chronic Challenges to Retinal Metabolism</brief_title>
  <official_title>Retinal Function in Relation to Transient or Chronic Challenges to Retinal Metabolism</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Glostrup University Hospital, Copenhagen</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Glostrup University Hospital, Copenhagen</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      The aim of the study is to investigate how the retina adapts to different metabolic&#xD;
      challenges, e.g. chronic systemic hypoxia, hyperglycemia, special training conditions or&#xD;
      diets as well as transient changes in the content of oxygen and glucose in the blood.&#xD;
    </textblock>
  </brief_summary>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Recruiting</last_known_status>
  <start_date>October 2012</start_date>
  <primary_completion_date type="Anticipated">December 2015</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Non-Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Retinal vessel diameters during hyperoxia</measure>
    <time_frame>Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia</time_frame>
    <description>Measurement of retinal vessel diameters before, during and after hyperoxic stimulation.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Retinal perfusion velocities during hyperoxia</measure>
    <time_frame>Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia</time_frame>
    <description>Measurement of retinal perfusion velocities before, during and after hyperoxic stimulation.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Retinal oximetry during hyperoxia</measure>
    <time_frame>Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia</time_frame>
    <description>Measurement of retinal oximetry status before, during and after hyperoxic stimulation.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Retinal vessel diameters during hyperglycemia</measure>
    <time_frame>Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load</time_frame>
    <description>Measurement of retinal vessel diameters before, during and after hyperglycemic stimulation.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Retinal perfusion during hyperglycemia</measure>
    <time_frame>Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load</time_frame>
    <description>Measurement of retinal perfusion velocities before, during and after hyperglycemic stimulation.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Retinal oximetry during hyperglycemia</measure>
    <time_frame>Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load</time_frame>
    <description>Measurement of retinal oximetry status before, during and after hyperglycemic stimulation.</description>
  </primary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Anticipated">120</enrollment>
  <condition>Healthy Individuals</condition>
  <condition>Patients With Diabetes.</condition>
  <arm_group>
    <arm_group_label>Healthy</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Healthy study participanats</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Diabetes</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Patients with diabetes</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Hyperoxia</intervention_name>
    <arm_group_label>Diabetes</arm_group_label>
    <arm_group_label>Healthy</arm_group_label>
    <other_name>Hyperoxia is achieved by short-term pure oxygen breathing.</other_name>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Glucose</intervention_name>
    <arm_group_label>Diabetes</arm_group_label>
    <arm_group_label>Healthy</arm_group_label>
    <other_name>Standardised oral glucose load.</other_name>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Healthy individuals&#xD;
&#xD;
        Inclusion Criteria:&#xD;
&#xD;
          -  Healthy volunteers.&#xD;
&#xD;
          -  No known systemic or ocular disease.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Any systemic or ocular disease.&#xD;
&#xD;
        Patients with diabetes&#xD;
&#xD;
        Inclusion criteria:&#xD;
&#xD;
          -  Diabetes mellitus&#xD;
&#xD;
          -  No intraocular disease other than conditions attributable to diabetes.&#xD;
&#xD;
        Exclusion criteria:&#xD;
&#xD;
          -  Intraocular disease other than conditions attributable to diabetes.&#xD;
&#xD;
          -  Systemic conditions which might contraindicate hyperoxic stimulation.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>70 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Oliver Klefter, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Glostrup UH</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Michael Larsen, Professor, DMSci</last_name>
    <role>Study Director</role>
    <affiliation>Glostrup UH</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Oliver Klefter, MD</last_name>
    <phone>+45 38 63 48 18</phone>
  </overall_contact>
  <location>
    <facility>
      <name>Department of Ophthalmology, Glostrup University Hospital</name>
      <address>
        <city>Glostrup</city>
        <zip>2600</zip>
        <country>Denmark</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Oliver Klefter, MD</last_name>
      <phone>+45 38 63 48 18</phone>
    </contact>
    <contact_backup>
      <last_name>Michael Larsen, Professor, DMSci</last_name>
    </contact_backup>
  </location>
  <location_countries>
    <country>Denmark</country>
  </location_countries>
  <verification_date>March 2015</verification_date>
  <study_first_submitted>October 31, 2012</study_first_submitted>
  <study_first_submitted_qc>November 2, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">November 6, 2012</study_first_posted>
  <last_update_submitted>March 10, 2015</last_update_submitted>
  <last_update_submitted_qc>March 10, 2015</last_update_submitted_qc>
  <last_update_posted type="Estimate">March 11, 2015</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Glostrup University Hospital, Copenhagen</investigator_affiliation>
    <investigator_full_name>Oliver Niels Klefter</investigator_full_name>
    <investigator_title>MD</investigator_title>
  </responsible_party>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT01721811
org study id: Klefter2
nct id: NCT01721811
lead sponsor: 
has dmc: No
The aim of the study is to investigate how the retina adapts to different metabolic
      challenges, e.g. chronic systemic hypoxia, hyperglycemia, special training conditions or
      diets as well as transient changes in the content of oxygen and glucose in the blood.
allocation: Non-Randomized
intervention model: Parallel Assignment
masking: None (Open Label)
measure: Retinal vessel diameters during hyperoxia
time frame: Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia
description: Measurement of retinal vessel diameters before, during and after hyperoxic stimulation.
measure: Retinal perfusion velocities during hyperoxia
time frame: Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia
description: Measurement of retinal perfusion velocities before, during and after hyperoxic stimulation.
measure: Retinal oximetry during hyperoxia
time frame: Before hyperoxia, after 15 minutes of hyperoxia, 30 minutes after ending hyperoxia
description: Measurement of retinal oximetry status before, during and after hyperoxic stimulation.
measure: Retinal vessel diameters during hyperglycemia
time frame: Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load
description: Measurement of retinal vessel diameters before, during and after hyperglycemic stimulation.
measure: Retinal perfusion during hyperglycemia
time frame: Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load
description: Measurement of retinal perfusion velocities before, during and after hyperglycemic stimulation.
measure: Retinal oximetry during hyperglycemia
time frame: Before glucose ingestion, every 30 minutes for 3 hours following oral glucose load
description: Measurement of retinal oximetry status before, during and after hyperglycemic stimulation.
arm group label: Healthy
arm group type: Experimental
description: Healthy study participanats
arm group label: Diabetes
arm group type: Experimental
description: Patients with diabetes
intervention type: Other
intervention name: Hyperoxia
arm group label: Diabetes
arm group label: Healthy
other name: Hyperoxia is achieved by short-term pure oxygen breathing.
intervention type: Other
intervention name: Glucose
arm group label: Diabetes
arm group label: Healthy
other name: Standardised oral glucose load.
criteria: 
gender: All
minimum age: 18 Years
maximum age: 70 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Oliver Klefter, MD
role: Principal Investigator
affiliation: Glostrup UH
last name: Michael Larsen, Professor, DMSci
role: Study Director
affiliation: Glostrup UH
last name: Oliver Klefter, MD
phone: +45 38 63 48 18
facility: 
status: Recruiting
contact: 
contact backup: 
country: Denmark
responsible party type: Principal Investigator
investigator affiliation: Glostrup University Hospital, Copenhagen
investigator full name: Oliver Niels Klefter
investigator title: MD