<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/NCT03249233</url>
  </required_header>
  <id_info>
    <org_study_id>22186</org_study_id>
    <nct_id>NCT03249233</nct_id>
  </id_info>
  <brief_title>Corneal Thickness Changes With Scleral Contact Lenses</brief_title>
  <official_title>Changes in Corneal Thickness in Keratoconic Eyes With Variation in Scleral Contact Lens Central Clearance</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of Waterloo</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Bausch &amp; Lomb Incorporated</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>University of Waterloo</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      The purpose of this study is to investigate changes in the corneal thickness of scleral&#xD;
      contact lens wearers in a keratoconic (KC) population and compare to age-matched controls.&#xD;
      The hypothesis is that scleral contact lens wear is associated with low levels of corneal&#xD;
      hypoxia including measurable changes in corneal thickness. Corneal thickness will be altered&#xD;
      post scleral lens wear compared to pre-lens wear and the amount of alteration will correlate&#xD;
      to the fitting characteristics in the central zone of the scleral lenses. We propose to take&#xD;
      a sample of keratoconic and control participants, fit them in scleral lenses, and to measure&#xD;
      topographic corneal thickness after 8-10 hours of scleral lens wear after three weeks of&#xD;
      wear, to compare two instruments in the measurement of corneal thickness, and to compare the&#xD;
      effects of varying central corneal clearance of the scleral lens on corneal thickness.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      The purpose of this study is to investigate changes in the corneal thickness of scleral&#xD;
      contact lens wearers in a keratoconic (KC) population and compare to age-matched controls.&#xD;
      The hypothesis is that scleral contact lens wear is associated with low levels of corneal&#xD;
      hypoxia including measurable changes in corneal thickness.&#xD;
&#xD;
      This will be a prospective, dispensing study design. The study will involve up to 20&#xD;
      keratoconic participants and up to 20 age matched controls. Participants will attend 1&#xD;
      screening/fitting visit wearing their habitual contact lenses where the two test lens designs&#xD;
      (350 and 450microns) will be fitted. There will then be a delivery visit for each design&#xD;
      (randomly selected) and a single follow up visit after 8-10 hours of scleral lens wear, three&#xD;
      weeks later. A washout period of a minimum of 48 hours will be applied between the cross-over&#xD;
      of each lens design. Lenses to be worn in this study will be made of Boston XO material and&#xD;
      are approved by Health Canada. The lenses will have a diameter of 14.8-17.0mm with a high and&#xD;
      low sagittal depth in the corneal zone. As to which of the two lenses is being assessed, both&#xD;
      the investigator and the participant will be masked as the assistant will provide the lenses&#xD;
      in an unlabeled case. Masking the investigator will prevent bias when measuring corneal&#xD;
      thickness and analyzing the data. The objectives of this study are to take a sample of&#xD;
      keratoconic and control participants, fit them in scleral lenses, and to measure topographic&#xD;
      corneal thickness after 8-10 hours of scleral lens wear after three weeks of wear, to compare&#xD;
      two instruments in the measurement of corneal thickness, and to compare the effects of&#xD;
      varying central corneal clearance of the scleral lens on corneal thickness. Secondary&#xD;
      objectives include comparing ocular physiological outcomes between the two test lens designs.&#xD;
      Corneal thickness will be altered post scleral lens wear compared to pre-lens wear and the&#xD;
      amount of alteration will correlate to the fitting characteristics in the central zone of the&#xD;
      scleral lenses.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Recruiting</last_known_status>
  <start_date type="Actual">June 22, 2017</start_date>
  <completion_date type="Anticipated">December 2020</completion_date>
  <primary_completion_date type="Anticipated">December 2020</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>Double (Participant, Investigator)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Corneal Thickness</measure>
    <time_frame>6 weeks</time_frame>
    <description>Corneal thickness after 8-10 hours of scleral contact lens wear will be measured with the Spectralis OCT and Oculus Pentacam</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Visual acuity</measure>
    <time_frame>6 weeks</time_frame>
    <description>Both high and low contrast visual acuity will be measured before and after 8-10 hours of scleral contact lens wear</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Conjunctival redness</measure>
    <time_frame>6 weeks</time_frame>
    <description>Conjunctival redness will be measured with the Keratograph before and after 8-10 hours of scleral lens wear</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Corneal and conjunctival staining</measure>
    <time_frame>6 weeks</time_frame>
    <description>Corneal and conjunctival staining will be assessed with the Keratograph and biomicroscope before and after 8-10 hours of scleral lens wear</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Tear biochemistry: proteases and cytokines</measure>
    <time_frame>6 weeks</time_frame>
    <description>The level of proteases (MMP-1, MMP-9) and cytokines (IL-1, IL-6, IL-8, TNFα) in each of the tear samples collected from the lenses will be measured using the Meso Scale Discovery System (MSD-ECL) before and after 8-10 hours of scleral lens wear.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Tear biochemistry: cell count</measure>
    <time_frame>6 weeks</time_frame>
    <description>Polymorphonuclear leukocyte (PMN) cells in each of the tear samples collected from the lenses will be analyzed and counted using the BD FACS Calibur™ Flow Cytometer and Bright-Line Hemacytometer before and after 8-10 hours of scleral lens wear.</description>
  </secondary_outcome>
  <number_of_arms>4</number_of_arms>
  <enrollment type="Anticipated">40</enrollment>
  <condition>Keratoconus</condition>
  <condition>Healthy Controls</condition>
  <arm_group>
    <arm_group_label>Keratoconics wearing ZenLens with high central clearance</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Scleral contact lenses designed to provide approximately 450 microns of central clearance.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Keratoconics wearing ZenLens with low central clearance</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Scleral contact lenses designed to provide approximately 350 microns of central clearance.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Healthy controls wearing ZenLens with high central clearance</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Scleral contact lenses designed to provide approximately 450 microns of central clearance.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Healthy controls wearing ZenLens with low central clearance</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Scleral contact lenses designed to provide approximately 350 microns of central clearance.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>ZenLens™</intervention_name>
    <description>The ZenLens™ semi-scleral lenses are manufactured by Alden Optic Laboratories Inc., Lancaster, NY. They will be made in Boston XO material.</description>
    <arm_group_label>Keratoconics wearing ZenLens with high central clearance</arm_group_label>
    <arm_group_label>Keratoconics wearing ZenLens with low central clearance</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Zen™ RC</intervention_name>
    <description>The Zen™ RC semi-scleral lenses are manufactured by Alden Optic Laboratories Inc., Lancaster, NY. They will be made in Boston XO material.</description>
    <arm_group_label>Healthy controls wearing ZenLens with high central clearance</arm_group_label>
    <arm_group_label>Healthy controls wearing ZenLens with low central clearance</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria (Test Group):&#xD;
&#xD;
          -  Had been diagnosed with keratoconus in at least one eye.&#xD;
&#xD;
          -  Is at least 18 years of age and has full legal capacity to volunteer.&#xD;
&#xD;
          -  Has read and understood the information consent letter.&#xD;
&#xD;
          -  Is willing and able to follow instructions and maintain the appointment schedule.&#xD;
&#xD;
        Inclusion Criteria (Control Group)&#xD;
&#xD;
          -  Had been NOT diagnosed with keratoconus in at least one eye.&#xD;
&#xD;
          -  Is at least 18 years of age and has full legal capacity to volunteer.&#xD;
&#xD;
          -  Has read and understood the information consent letter.&#xD;
&#xD;
          -  Is willing and able to follow instructions and maintain the appointment schedule.&#xD;
&#xD;
        Exclusion Criteria (Test Group):&#xD;
&#xD;
          -  Is using any topical medications that will affect ocular health.&#xD;
&#xD;
          -  Has any ocular pathology or severe insufficiency of lacrimal secretion (severe dry&#xD;
             eyes) that would affect the wearing of contact lenses.&#xD;
&#xD;
          -  Has persistent, clinically significant corneal or conjunctival staining using sodium&#xD;
             fluorescein dye.&#xD;
&#xD;
          -  Has any clinically significant lid or conjunctival abnormalities and active&#xD;
             neovascularization.&#xD;
&#xD;
          -  Is aphakic.&#xD;
&#xD;
          -  Has undergone penetrating keratoplasty.&#xD;
&#xD;
          -  Is participating in any other type of eye related clinical or research study.&#xD;
&#xD;
          -  Has any known allergies or sensitivity to the diagnostic pharmaceuticals or products,&#xD;
             such as fluorescein, used in this study.&#xD;
&#xD;
        Exclusion Criteria (Control Group):&#xD;
&#xD;
          -  Is using any topical medications that will affect ocular health.&#xD;
&#xD;
          -  Has any ocular pathology or severe insufficiency of lacrimal secretion (severe dry&#xD;
             eyes) that would affect the wearing of contact lenses.&#xD;
&#xD;
          -  Has persistent, clinically significant corneal or conjunctival staining using sodium&#xD;
             fluorescein dye.&#xD;
&#xD;
          -  Has any clinically significant lid or conjunctival abnormalities and active&#xD;
             neovascularization.&#xD;
&#xD;
          -  Is aphakic.&#xD;
&#xD;
          -  Has undergone any corneal surgery.&#xD;
&#xD;
          -  Is participating in any other type of eye related clinical or research study.&#xD;
&#xD;
          -  Has any known allergies or sensitivity to the diagnostic pharmaceuticals or products,&#xD;
             such as fluorescein, used in this study.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Luigina Sorbara, OD MSc</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of Waterloo</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Kirsten S Carter, BSc OD</last_name>
    <phone>5193018487</phone>
    <email>kirsten.carter@uwaterloo.ca</email>
  </overall_contact>
  <location>
    <facility>
      <name>University of Waterloo School of Optometry and Vision Science</name>
      <address>
        <city>Waterloo</city>
        <state>Ontario</state>
        <zip>N2L3G1</zip>
        <country>Canada</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Kirsten S Carter, BSc OD</last_name>
      <phone>5193018487</phone>
      <email>kirsten.carter@uwaterloo.ca</email>
    </contact>
    <contact_backup>
      <last_name>Luigina Sorbara, OD MSc</last_name>
      <phone>519-888-4567</phone>
      <phone_ext>33085</phone_ext>
      <email>gsorbara@uwaterloo.ca</email>
    </contact_backup>
  </location>
  <location_countries>
    <country>Canada</country>
  </location_countries>
  <reference>
    <citation>van der Worp E, Bornman D, Ferreira DL, Faria-Ribeiro M, Garcia-Porta N, Gonzalez-Meijome JM. Modern scleral contact lenses: A review. Cont Lens Anterior Eye. 2014 Aug;37(4):240-50. doi: 10.1016/j.clae.2014.02.002. Epub 2014 Mar 12.</citation>
    <PMID>24631015</PMID>
  </reference>
  <reference>
    <citation>Romero-Rangel T, Stavrou P, Cotter J, Rosenthal P, Baltatzis S, Foster CS. Gas-permeable scleral contact lens therapy in ocular surface disease. Am J Ophthalmol. 2000 Jul;130(1):25-32. doi: 10.1016/s0002-9394(00)00378-0.</citation>
    <PMID>11004256</PMID>
  </reference>
  <reference>
    <citation>Walker MK, Bergmanson JP, Miller WL, Marsack JD, Johnson LA. Complications and fitting challenges associated with scleral contact lenses: A review. Cont Lens Anterior Eye. 2016 Apr;39(2):88-96. doi: 10.1016/j.clae.2015.08.003. Epub 2015 Sep 2.</citation>
    <PMID>26341076</PMID>
  </reference>
  <reference>
    <citation>Ucakhan OO, Ozkan M, Kanpolat A. Corneal thickness measurements in normal and keratoconic eyes: Pentacam comprehensive eye scanner versus noncontact specular microscopy and ultrasound pachymetry. J Cataract Refract Surg. 2006 Jun;32(6):970-7. doi: 10.1016/j.jcrs.2006.02.037.</citation>
    <PMID>16814055</PMID>
  </reference>
  <reference>
    <citation>Liesegang TJ. Contact lens-related microbial keratitis: Part I: Epidemiology. Cornea. 1997 Mar;16(2):125-31.</citation>
    <PMID>9071523</PMID>
  </reference>
  <verification_date>April 2020</verification_date>
  <study_first_submitted>June 15, 2017</study_first_submitted>
  <study_first_submitted_qc>August 14, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">August 15, 2017</study_first_posted>
  <last_update_submitted>April 8, 2020</last_update_submitted>
  <last_update_submitted_qc>April 8, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">April 10, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>University of Waterloo</investigator_affiliation>
    <investigator_full_name>Luigina Sorbara</investigator_full_name>
    <investigator_title>Associate Professor</investigator_title>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Keratoconus</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- 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/NCT03249233
org study id: 22186
nct id: NCT03249233
lead sponsor: 
collaborator: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
The purpose of this study is to investigate changes in the corneal thickness of scleral
      contact lens wearers in a keratoconic (KC) population and compare to age-matched controls.
      The hypothesis is that scleral contact lens wear is associated with low levels of corneal
      hypoxia including measurable changes in corneal thickness. Corneal thickness will be altered
      post scleral lens wear compared to pre-lens wear and the amount of alteration will correlate
      to the fitting characteristics in the central zone of the scleral lenses. We propose to take
      a sample of keratoconic and control participants, fit them in scleral lenses, and to measure
      topographic corneal thickness after 8-10 hours of scleral lens wear after three weeks of
      wear, to compare two instruments in the measurement of corneal thickness, and to compare the
      effects of varying central corneal clearance of the scleral lens on corneal thickness.
The purpose of this study is to investigate changes in the corneal thickness of scleral
      contact lens wearers in a keratoconic (KC) population and compare to age-matched controls.
      The hypothesis is that scleral contact lens wear is associated with low levels of corneal
      hypoxia including measurable changes in corneal thickness.

      This will be a prospective, dispensing study design. The study will involve up to 20
      keratoconic participants and up to 20 age matched controls. Participants will attend 1
      screening/fitting visit wearing their habitual contact lenses where the two test lens designs
      (350 and 450microns) will be fitted. There will then be a delivery visit for each design
      (randomly selected) and a single follow up visit after 8-10 hours of scleral lens wear, three
      weeks later. A washout period of a minimum of 48 hours will be applied between the cross-over
      of each lens design. Lenses to be worn in this study will be made of Boston XO material and
      are approved by Health Canada. The lenses will have a diameter of 14.8-17.0mm with a high and
      low sagittal depth in the corneal zone. As to which of the two lenses is being assessed, both
      the investigator and the participant will be masked as the assistant will provide the lenses
      in an unlabeled case. Masking the investigator will prevent bias when measuring corneal
      thickness and analyzing the data. The objectives of this study are to take a sample of
      keratoconic and control participants, fit them in scleral lenses, and to measure topographic
      corneal thickness after 8-10 hours of scleral lens wear after three weeks of wear, to compare
      two instruments in the measurement of corneal thickness, and to compare the effects of
      varying central corneal clearance of the scleral lens on corneal thickness. Secondary
      objectives include comparing ocular physiological outcomes between the two test lens designs.
      Corneal thickness will be altered post scleral lens wear compared to pre-lens wear and the
      amount of alteration will correlate to the fitting characteristics in the central zone of the
      scleral lenses.
allocation: Randomized
intervention model: Parallel Assignment
primary purpose: Treatment
masking: Double (Participant, Investigator)
measure: Corneal Thickness
time frame: 6 weeks
description: Corneal thickness after 8-10 hours of scleral contact lens wear will be measured with the Spectralis OCT and Oculus Pentacam
measure: Visual acuity
time frame: 6 weeks
description: Both high and low contrast visual acuity will be measured before and after 8-10 hours of scleral contact lens wear
measure: Conjunctival redness
time frame: 6 weeks
description: Conjunctival redness will be measured with the Keratograph before and after 8-10 hours of scleral lens wear
measure: Corneal and conjunctival staining
time frame: 6 weeks
description: Corneal and conjunctival staining will be assessed with the Keratograph and biomicroscope before and after 8-10 hours of scleral lens wear
measure: Tear biochemistry: proteases and cytokines
time frame: 6 weeks
description: The level of proteases (MMP-1, MMP-9) and cytokines (IL-1, IL-6, IL-8, TNFα) in each of the tear samples collected from the lenses will be measured using the Meso Scale Discovery System (MSD-ECL) before and after 8-10 hours of scleral lens wear.
measure: Tear biochemistry: cell count
time frame: 6 weeks
description: Polymorphonuclear leukocyte (PMN) cells in each of the tear samples collected from the lenses will be analyzed and counted using the BD FACS Calibur™ Flow Cytometer and Bright-Line Hemacytometer before and after 8-10 hours of scleral lens wear.
arm group label: Keratoconics wearing ZenLens with high central clearance
arm group type: Experimental
description: Scleral contact lenses designed to provide approximately 450 microns of central clearance.
arm group label: Keratoconics wearing ZenLens with low central clearance
arm group type: Experimental
description: Scleral contact lenses designed to provide approximately 350 microns of central clearance.
arm group label: Healthy controls wearing ZenLens with high central clearance
arm group type: Active Comparator
description: Scleral contact lenses designed to provide approximately 450 microns of central clearance.
arm group label: Healthy controls wearing ZenLens with low central clearance
arm group type: Active Comparator
description: Scleral contact lenses designed to provide approximately 350 microns of central clearance.
intervention type: Device
intervention name: ZenLens™
description: The ZenLens™ semi-scleral lenses are manufactured by Alden Optic Laboratories Inc., Lancaster, NY. They will be made in Boston XO material.
arm group label: Keratoconics wearing ZenLens with high central clearance
arm group label: Keratoconics wearing ZenLens with low central clearance
intervention type: Device
intervention name: Zen™ RC
description: The Zen™ RC semi-scleral lenses are manufactured by Alden Optic Laboratories Inc., Lancaster, NY. They will be made in Boston XO material.
arm group label: Healthy controls wearing ZenLens with high central clearance
arm group label: Healthy controls wearing ZenLens with low central clearance
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
last name: Luigina Sorbara, OD MSc
role: Principal Investigator
affiliation: University of Waterloo
last name: Kirsten S Carter, BSc OD
phone: 5193018487
email: kirsten.carter@uwaterloo.ca
facility: 
status: Recruiting
contact: 
contact backup: 
country: Canada
citation: van der Worp E, Bornman D, Ferreira DL, Faria-Ribeiro M, Garcia-Porta N, Gonzalez-Meijome JM. Modern scleral contact lenses: A review. Cont Lens Anterior Eye. 2014 Aug;37(4):240-50. doi: 10.1016/j.clae.2014.02.002. Epub 2014 Mar 12.
PMID: 24631015
citation: Romero-Rangel T, Stavrou P, Cotter J, Rosenthal P, Baltatzis S, Foster CS. Gas-permeable scleral contact lens therapy in ocular surface disease. Am J Ophthalmol. 2000 Jul;130(1):25-32. doi: 10.1016/s0002-9394(00)00378-0.
PMID: 11004256
citation: Walker MK, Bergmanson JP, Miller WL, Marsack JD, Johnson LA. Complications and fitting challenges associated with scleral contact lenses: A review. Cont Lens Anterior Eye. 2016 Apr;39(2):88-96. doi: 10.1016/j.clae.2015.08.003. Epub 2015 Sep 2.
PMID: 26341076
citation: Ucakhan OO, Ozkan M, Kanpolat A. Corneal thickness measurements in normal and keratoconic eyes: Pentacam comprehensive eye scanner versus noncontact specular microscopy and ultrasound pachymetry. J Cataract Refract Surg. 2006 Jun;32(6):970-7. doi: 10.1016/j.jcrs.2006.02.037.
PMID: 16814055
citation: Liesegang TJ. Contact lens-related microbial keratitis: Part I: Epidemiology. Cornea. 1997 Mar;16(2):125-31.
PMID: 9071523
responsible party type: Principal Investigator
investigator affiliation: University of Waterloo
investigator full name: Luigina Sorbara
investigator title: Associate Professor
mesh term: Keratoconus
sharing ipd: No