<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/NCT02995174</url>
  </required_header>
  <id_info>
    <org_study_id>HMRF11122991</org_study_id>
    <nct_id>NCT02995174</nct_id>
  </id_info>
  <brief_title>Will Perceptual Learning Via Video Game Playing Improve Visual Acuity Stereopsis &amp; Fixation Stability in Mild Amblyopes?</brief_title>
  <official_title>Will Perceptual Learning Via Video Game Playing Improve Visual Acuity, Stereopsis and Fixation Stability in Mild Amblyopes? Part 2 Study</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>The Hong Kong Polytechnic University</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>The Hong Kong Polytechnic University</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Contrast balanced dichoptic videogame training has been found to improve sensory functions in&#xD;
      adults with amblyopia; best corrected distance visual acuity (BCVA) and stereopsis, but its&#xD;
      effect on motor function, namely amblyopic eye fixation stability, is unknown. Furthermore,&#xD;
      the effect of treatment in cases of mild amblyopia is not well understood. The aim of this&#xD;
      study is to find out the difference on fixation stability, BCVA and stereopsis in mild&#xD;
      amblyopes after 6 weeks' contrast balanced dichoptic video game training.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Objectives: To assess the change of fixation stability as well as visual acuity and&#xD;
      stereopsis before and after training mild amblyopia by perceptual learning through dichoptic&#xD;
      video game playing.&#xD;
&#xD;
      Hypothesis: It has been shown that the visual acuity, stereopsis and fixation stability are&#xD;
      compromised in amblyopic eye. Perceptual learning via video game playing has been found&#xD;
      effective in improving visual acuity and stereoacuity in moderate and severe amblyopic eyes,&#xD;
      but there is no study on such treatment in mild amblyopia. In this study, we hypothesize that&#xD;
      fixation stability, visual acuity and stereopsis will be improved after training by dichoptic&#xD;
      video game playing in mild amblyopia.&#xD;
&#xD;
      Methods: Participants (aged 7 or above) with Best Corrected Visual Acuity (BCVA) ≤ 0.28&#xD;
      logMAR in the amblyopic eye and an interocular acuity difference ≥ 0.2 logMAR will be&#xD;
      recruited. An anaglyphic, contrast balanced dichoptic video game will be provided on an i-Pod&#xD;
      Touch (Apple Inc.) for 6 weeks of home-based training (60 mins per day). Fixation stability&#xD;
      quantified using bivariate contour ellipse area (BCEA by micro-perimeter (MP) Nidek MP-1),&#xD;
      BCVA and stereopsis will be assessed before and after treatment.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>August 2015</start_date>
  <completion_date type="Actual">December 31, 2018</completion_date>
  <primary_completion_date type="Actual">December 18, 2017</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>Sequential Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes</measure>
    <time_frame>6 weeks</time_frame>
    <description>Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. The 95% bivariate contour ellipse area will be adopted in units of degree square.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes</measure>
    <time_frame>6 weeks</time_frame>
    <description>Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. Best corrected visual acuity will be measured in log MAR unit.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes</measure>
    <time_frame>6 weeks</time_frame>
    <description>Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes. The Titmus and Randot preschool stereopsis test will be used and the measurements are recorded in ' second of arc'.</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">23</enrollment>
  <condition>Amblyopia</condition>
  <arm_group>
    <arm_group_label>Intervention (dichoptic video game play)</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Mild amblyopic subjects will be asked to play dichoptic video game in an i-Pod touch device for 1 hour per day in 6 weeks.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Control (video game play)</arm_group_label>
    <arm_group_type>Placebo Comparator</arm_group_type>
    <description>Mild amblyopic subjects will be asked to play video game in an i-Pod touch device for 1 hour per day in 6 weeks.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Dichoptic video game in an i-Pod touch device</intervention_name>
    <description>Amblyope will wear a pair of red green goggles and play the video game with 'contrast-balanced' images displayed on the screen of an i-Pod touch device. The eye with weaker eyesight will see the image with high contrast, and the good eye will see the image with low contrast. The subject will play the game one hour per day for 6 weeks.</description>
    <arm_group_label>Intervention (dichoptic video game play)</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Video game in an i-Pod touch device</intervention_name>
    <description>Amblyope will wear a pair of red green goggles and play the video game with equal contrast images displayed on the screen of an i-Pod touch device. Both eyes will see the image of same contrast. The subject will play the game one hour per day for 6 weeks.</description>
    <arm_group_label>Control (video game play)</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Best corrected VA in amblyopic eye ≤ 0.28 log MAR, fellow eye VA with an interocular&#xD;
             VA difference ≥ 0.20 log MAR;&#xD;
&#xD;
          -  Amblyopia could be in form of strabismic, anisometropic and mixed (both strabismic and&#xD;
             anisometropic)&#xD;
&#xD;
          -  Able to complete 3 successful measurements (each with 30 seconds fixation) of BCEA by&#xD;
             the MP-1 systems in each eye&#xD;
&#xD;
          -  Able to align the nonius cross (≤10mm horizontal error and 5mm vertical error) in the&#xD;
             i-Pod game&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Myopia of spherical equivalent power &gt; -6.0 diopter in either eye&#xD;
&#xD;
          -  Previous intraocular surgery&#xD;
&#xD;
          -  any types of ocular pathology (e.g. media opacities or retinal lesion)&#xD;
&#xD;
          -  Previous or current history of neurological problem&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>7 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Carly Lam, PhD</last_name>
    <role>Principal Investigator</role>
    <affiliation>The Hong Kong Polytechnic University</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>The Hong Kong Polytechnic University</name>
      <address>
        <city>Hong Kong</city>
        <country>Hong Kong</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Hong Kong</country>
  </location_countries>
  <reference>
    <citation>Birch EE, Li SL, Jost RM, Morale SE, De La Cruz A, Stager D Jr, Dao L, Stager DR Sr. Binocular iPad treatment for amblyopia in preschool children. J AAPOS. 2015 Feb;19(1):6-11. doi: 10.1016/j.jaapos.2014.09.009.</citation>
    <PMID>25727578</PMID>
  </reference>
  <reference>
    <citation>Birch EE, Subramanian V, Weakley DR. Fixation instability in anisometropic children with reduced stereopsis. J AAPOS. 2013 Jun;17(3):287-90. doi: 10.1016/j.jaapos.2013.03.011.</citation>
    <PMID>23791411</PMID>
  </reference>
  <reference>
    <citation>Chung ST, Kumar G, Li RW, Levi DM. Characteristics of fixational eye movements in amblyopia: Limitations on fixation stability and acuity? Vision Res. 2015 Sep;114:87-99. doi: 10.1016/j.visres.2015.01.016. Epub 2015 Feb 7.</citation>
    <PMID>25668775</PMID>
  </reference>
  <reference>
    <citation>Gonzalez EG, Wong AM, Niechwiej-Szwedo E, Tarita-Nistor L, Steinbach MJ. Eye position stability in amblyopia and in normal binocular vision. Invest Ophthalmol Vis Sci. 2012 Aug 9;53(9):5386-94. doi: 10.1167/iovs.12-9941.</citation>
    <PMID>22789926</PMID>
  </reference>
  <reference>
    <citation>Guo CX, Babu RJ, Black JM, Bobier WR, Lam CS, Dai S, Gao TY, Hess RF, Jenkins M, Jiang Y, Kowal L, Parag V, South J, Staffieri SE, Walker N, Wadham A, Thompson B; BRAVO study team. Binocular treatment of amblyopia using videogames (BRAVO): study protocol for a randomised controlled trial. Trials. 2016 Oct 18;17(1):504. doi: 10.1186/s13063-016-1635-3.</citation>
    <PMID>27756405</PMID>
  </reference>
  <reference>
    <citation>Hess RF, Babu RJ, Clavagnier S, Black J, Bobier W, Thompson B. The iPod binocular home-based treatment for amblyopia in adults: efficacy and compliance. Clin Exp Optom. 2014 Sep;97(5):389-98. doi: 10.1111/cxo.12192. Epub 2014 Aug 18.</citation>
    <PMID>25131694</PMID>
  </reference>
  <reference>
    <citation>Li SL, Jost RM, Morale SE, Stager DR, Dao L, Stager D, Birch EE. A binocular iPad treatment for amblyopic children. Eye (Lond). 2014 Oct;28(10):1246-53. doi: 10.1038/eye.2014.165. Epub 2014 Jul 25.</citation>
    <PMID>25060850</PMID>
  </reference>
  <reference>
    <citation>Shaikh AG, Otero-Millan J, Kumar P, Ghasia FF. Abnormal Fixational Eye Movements in Amblyopia. PLoS One. 2016 Mar 1;11(3):e0149953. doi: 10.1371/journal.pone.0149953. eCollection 2016.</citation>
    <PMID>26930079</PMID>
  </reference>
  <reference>
    <citation>Subramanian V, Jost RM, Birch EE. A quantitative study of fixation stability in amblyopia. Invest Ophthalmol Vis Sci. 2013 Mar 19;54(3):1998-2003. doi: 10.1167/iovs.12-11054.</citation>
    <PMID>23372053</PMID>
  </reference>
  <reference>
    <citation>To L, Thompson B, Blum JR, Maehara G, Hess RF, Cooperstock JR. A game platform for treatment of amblyopia. IEEE Trans Neural Syst Rehabil Eng. 2011 Jun;19(3):280-9. doi: 10.1109/TNSRE.2011.2115255. Epub 2011 Feb 17.</citation>
    <PMID>21335317</PMID>
  </reference>
  <verification_date>August 2020</verification_date>
  <study_first_submitted>December 14, 2016</study_first_submitted>
  <study_first_submitted_qc>December 14, 2016</study_first_submitted_qc>
  <study_first_posted type="Estimate">December 16, 2016</study_first_posted>
  <last_update_submitted>August 2, 2020</last_update_submitted>
  <last_update_submitted_qc>August 2, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">August 4, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>The Hong Kong Polytechnic University</investigator_affiliation>
    <investigator_full_name>Carly Lam</investigator_full_name>
    <investigator_title>Professor</investigator_title>
  </responsible_party>
  <keyword>amblyopia</keyword>
  <keyword>fixation stability</keyword>
  <keyword>perceptual learning</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Amblyopia</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/NCT02995174
org study id: HMRF11122991
nct id: NCT02995174
lead sponsor: 
has dmc: Yes
Contrast balanced dichoptic videogame training has been found to improve sensory functions in
      adults with amblyopia; best corrected distance visual acuity (BCVA) and stereopsis, but its
      effect on motor function, namely amblyopic eye fixation stability, is unknown. Furthermore,
      the effect of treatment in cases of mild amblyopia is not well understood. The aim of this
      study is to find out the difference on fixation stability, BCVA and stereopsis in mild
      amblyopes after 6 weeks' contrast balanced dichoptic video game training.
Objectives: To assess the change of fixation stability as well as visual acuity and
      stereopsis before and after training mild amblyopia by perceptual learning through dichoptic
      video game playing.

      Hypothesis: It has been shown that the visual acuity, stereopsis and fixation stability are
      compromised in amblyopic eye. Perceptual learning via video game playing has been found
      effective in improving visual acuity and stereoacuity in moderate and severe amblyopic eyes,
      but there is no study on such treatment in mild amblyopia. In this study, we hypothesize that
      fixation stability, visual acuity and stereopsis will be improved after training by dichoptic
      video game playing in mild amblyopia.

      Methods: Participants (aged 7 or above) with Best Corrected Visual Acuity (BCVA) ≤ 0.28
      logMAR in the amblyopic eye and an interocular acuity difference ≥ 0.2 logMAR will be
      recruited. An anaglyphic, contrast balanced dichoptic video game will be provided on an i-Pod
      Touch (Apple Inc.) for 6 weeks of home-based training (60 mins per day). Fixation stability
      quantified using bivariate contour ellipse area (BCEA by micro-perimeter (MP) Nidek MP-1),
      BCVA and stereopsis will be assessed before and after treatment.
allocation: Non-Randomized
intervention model: Sequential Assignment
primary purpose: Treatment
masking: None (Open Label)
measure: Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes
time frame: 6 weeks
description: Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. The 95% bivariate contour ellipse area will be adopted in units of degree square.
measure: Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes
time frame: 6 weeks
description: Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. Best corrected visual acuity will be measured in log MAR unit.
measure: Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes
time frame: 6 weeks
description: Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes. The Titmus and Randot preschool stereopsis test will be used and the measurements are recorded in ' second of arc'.
arm group label: Intervention (dichoptic video game play)
arm group type: Experimental
description: Mild amblyopic subjects will be asked to play dichoptic video game in an i-Pod touch device for 1 hour per day in 6 weeks.
arm group label: Control (video game play)
arm group type: Placebo Comparator
description: Mild amblyopic subjects will be asked to play video game in an i-Pod touch device for 1 hour per day in 6 weeks.
intervention type: Device
intervention name: Dichoptic video game in an i-Pod touch device
description: Amblyope will wear a pair of red green goggles and play the video game with 'contrast-balanced' images displayed on the screen of an i-Pod touch device. The eye with weaker eyesight will see the image with high contrast, and the good eye will see the image with low contrast. The subject will play the game one hour per day for 6 weeks.
arm group label: Intervention (dichoptic video game play)
intervention type: Device
intervention name: Video game in an i-Pod touch device
description: Amblyope will wear a pair of red green goggles and play the video game with equal contrast images displayed on the screen of an i-Pod touch device. Both eyes will see the image of same contrast. The subject will play the game one hour per day for 6 weeks.
arm group label: Control (video game play)
criteria: 
gender: All
minimum age: 7 Years
maximum age: N/A
healthy volunteers: No
last name: Carly Lam, PhD
role: Principal Investigator
affiliation: The Hong Kong Polytechnic University
facility: 
country: Hong Kong
citation: Birch EE, Li SL, Jost RM, Morale SE, De La Cruz A, Stager D Jr, Dao L, Stager DR Sr. Binocular iPad treatment for amblyopia in preschool children. J AAPOS. 2015 Feb;19(1):6-11. doi: 10.1016/j.jaapos.2014.09.009.
PMID: 25727578
citation: Birch EE, Subramanian V, Weakley DR. Fixation instability in anisometropic children with reduced stereopsis. J AAPOS. 2013 Jun;17(3):287-90. doi: 10.1016/j.jaapos.2013.03.011.
PMID: 23791411
citation: Chung ST, Kumar G, Li RW, Levi DM. Characteristics of fixational eye movements in amblyopia: Limitations on fixation stability and acuity? Vision Res. 2015 Sep;114:87-99. doi: 10.1016/j.visres.2015.01.016. Epub 2015 Feb 7.
PMID: 25668775
citation: Gonzalez EG, Wong AM, Niechwiej-Szwedo E, Tarita-Nistor L, Steinbach MJ. Eye position stability in amblyopia and in normal binocular vision. Invest Ophthalmol Vis Sci. 2012 Aug 9;53(9):5386-94. doi: 10.1167/iovs.12-9941.
PMID: 22789926
citation: Guo CX, Babu RJ, Black JM, Bobier WR, Lam CS, Dai S, Gao TY, Hess RF, Jenkins M, Jiang Y, Kowal L, Parag V, South J, Staffieri SE, Walker N, Wadham A, Thompson B; BRAVO study team. Binocular treatment of amblyopia using videogames (BRAVO): study protocol for a randomised controlled trial. Trials. 2016 Oct 18;17(1):504. doi: 10.1186/s13063-016-1635-3.
PMID: 27756405
citation: Hess RF, Babu RJ, Clavagnier S, Black J, Bobier W, Thompson B. The iPod binocular home-based treatment for amblyopia in adults: efficacy and compliance. Clin Exp Optom. 2014 Sep;97(5):389-98. doi: 10.1111/cxo.12192. Epub 2014 Aug 18.
PMID: 25131694
citation: Li SL, Jost RM, Morale SE, Stager DR, Dao L, Stager D, Birch EE. A binocular iPad treatment for amblyopic children. Eye (Lond). 2014 Oct;28(10):1246-53. doi: 10.1038/eye.2014.165. Epub 2014 Jul 25.
PMID: 25060850
citation: Shaikh AG, Otero-Millan J, Kumar P, Ghasia FF. Abnormal Fixational Eye Movements in Amblyopia. PLoS One. 2016 Mar 1;11(3):e0149953. doi: 10.1371/journal.pone.0149953. eCollection 2016.
PMID: 26930079
citation: Subramanian V, Jost RM, Birch EE. A quantitative study of fixation stability in amblyopia. Invest Ophthalmol Vis Sci. 2013 Mar 19;54(3):1998-2003. doi: 10.1167/iovs.12-11054.
PMID: 23372053
citation: To L, Thompson B, Blum JR, Maehara G, Hess RF, Cooperstock JR. A game platform for treatment of amblyopia. IEEE Trans Neural Syst Rehabil Eng. 2011 Jun;19(3):280-9. doi: 10.1109/TNSRE.2011.2115255. Epub 2011 Feb 17.
PMID: 21335317
responsible party type: Principal Investigator
investigator affiliation: The Hong Kong Polytechnic University
investigator full name: Carly Lam
investigator title: Professor
mesh term: Amblyopia
sharing ipd: No