<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/NCT02995629</url>
  </required_header>
  <id_info>
    <org_study_id>16-560</org_study_id>
    <nct_id>NCT02995629</nct_id>
  </id_info>
  <brief_title>Patient Comfort Using Green vs. Yellow Pan Retinal Photocoagulation</brief_title>
  <official_title>Patient Comfort Using Green (532 nm) Versus Yellow (577 nm) Laser Indirect Ophthalmoscopy Panretinal Photocoagulation for Proliferative Diabetic Retinopathy</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Wills Eye</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Mid Atlantic Retina</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>Wills Eye</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Our aim is to compare patient comfort when using the 532 nanometer (green) wavelength laser&#xD;
      to the 577 nanometer (yellow) wavelength laser during pan retinal photocoagulation to treat&#xD;
      patients with diabetic retinopathy. Secondary outcome measures will be power (mW) required to&#xD;
      achieve gray-white retinal burns and duration of treatment.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      As demonstrated in the Diabetic Retinopathy Study (DRS), panretinal photocoagulation (PRP)&#xD;
      reduces the risk of severe vision loss in patients with proliferative diabetic retinopathy.&#xD;
      The DRS recommended that PRP treatment consist of 1,200 - 1,600 laser burns 500 µm in size,&#xD;
      one half to one burn width apart, applied to the peripheral retina in a scatter fashion. Most&#xD;
      patients who undergo PRP experience discomfort/pain during the procedure. Once present, pain&#xD;
      can affect the number and quality of burns delivered and can indirectly increase the number&#xD;
      of sessions required to complete the therapy.This may in turn adversely affect patient&#xD;
      compliance. Although retrobulbar and peribulbar blocks can provide adequate anesthesia for&#xD;
      PRP, these anesthetic methods carry rare but serious risks such as retrobulbar hemorrhage.&#xD;
      Previous studies have explored other ways to reduce discomfort related to PRP, including&#xD;
      optimization of laser settings, oral and topical analgesics, subconjunctival anesthesia, and&#xD;
      even acupuncture.&#xD;
&#xD;
      Currently, green lasers (521 - 532 nm wavelength) are most commonly utilized for performing&#xD;
      PRP in clinical practice. Yellow lasers (577 nm wavelength) have been of recent interest in&#xD;
      treating diabetic macular edema with micropulse subthreshold grid photocoagulation, but have&#xD;
      not been extensively studied in PRP for diabetic retinopathy. Compared to shorter wavelength&#xD;
      laser, yellow laser comports high transmission through dense ocular media and less light&#xD;
      scattering than shorter wavelengths which minimizes spot size and reduces thermal spread. The&#xD;
      limited literature comparing green and yellow laser for PRP in diabetic retinopathy has shown&#xD;
      that yellow laser requires less power to achieve a retinal burn. In theory this should&#xD;
      translate into a reduction in perceived pain experienced during PRP, however a comparison of&#xD;
      green and yellow lasers in this regard has not yet been directly examined and quantified.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>March 2016</start_date>
  <completion_date type="Actual">October 2016</completion_date>
  <primary_completion_date type="Actual">October 2016</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>Crossover Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>Single (Participant)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Perceived patient pain assessment</measure>
    <time_frame>a single time point within 2 minutes of completing laser treatment</time_frame>
    <description>Assessed using a standardized Wong-Baker faces pain scale</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Minimum power requirement to achieve moderate gray-white retinal burns</measure>
    <time_frame>During treatment</time_frame>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Time of treatment</measure>
    <time_frame>During treatment</time_frame>
    <description>Time required to treat with each laser</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">40</enrollment>
  <condition>Proliferative Diabetic Retinopathy - High Risk</condition>
  <arm_group>
    <arm_group_label>green (532 nm) laser</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>scatter laser indirect ophthalmoscopy pan retinal photocoagulation</description>
  </arm_group>
  <arm_group>
    <arm_group_label>yellow (577 nm) laser</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>scatter laser indirect ophthalmoscopy pan retinal photocoagulation</description>
  </arm_group>
  <intervention>
    <intervention_type>Procedure</intervention_type>
    <intervention_name>laser indirect ophthalmoscopy pan retinal photocoagulation</intervention_name>
    <description>Prior to procedure, eligible patient is dilated and a topical anesthesia is administered 3 to 5 minutes prior to treatment initiation&#xD;
Treatment duration is fixed at 50 minutes and power is titrated until moderate gray-white burns are achieved, avoiding long ciliary nerves&#xD;
Target treatment of 250 spots&#xD;
Only one eye per eligible patient randomized with regard to whether green or yellow laser utilized first&#xD;
After treatment,pain assessment conducted:spot count, laser parameters and treatment duration recorded for each respective laser wavelength</description>
    <arm_group_label>green (532 nm) laser</arm_group_label>
    <arm_group_label>yellow (577 nm) laser</arm_group_label>
    <other_name>PRP laser</other_name>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  patient of Wills Eye Hospital Retina Service and/or Mid Atlantic Retina&#xD;
&#xD;
          -  volunteer patients age 18 years and older.&#xD;
&#xD;
          -  healthy enough to participate in the study.&#xD;
&#xD;
          -  willing and able to consent to participation in the study.&#xD;
&#xD;
          -  diagnosis of PDR with HRC based on clinical criteria outlined by the DRS.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  patient less than 18 years of age&#xD;
&#xD;
          -  institutionalized patient&#xD;
&#xD;
          -  prisoner&#xD;
&#xD;
          -  significant media opacity obscuring a view of the superior retina&#xD;
&#xD;
          -  history of intra-ocular surgery except cataract surgery&#xD;
&#xD;
          -  history of PRP laser within the last 30 days&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Allen Chiang, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Mid Atlantic Retina</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Mid Atlantic Retina- Wills Eye Institute</name>
      <address>
        <city>Philadelphia</city>
        <state>Pennsylvania</state>
        <zip>19107</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <reference>
    <citation>Photocoagulation treatment of proliferative diabetic retinopathy. Clinical application of Diabetic Retinopathy Study (DRS) findings, DRS Report Number 8. The Diabetic Retinopathy Study Research Group. Ophthalmology. 1981 Jul;88(7):583-600.</citation>
    <PMID>7196564</PMID>
  </reference>
  <reference>
    <citation>Richardson C, Waterman H. Pain relief during panretinal photocoagulation for diabetic retinopathy: a national survey. Eye (Lond). 2009 Dec;23(12):2233-7. doi: 10.1038/eye.2008.421.</citation>
    <PMID>19169228</PMID>
  </reference>
  <reference>
    <citation>Alvarez-Verduzco O, Garcia-Aguirre G, Lopez-Ramos Mde L, Vera-Rodriguez S, Guerrero-Naranjo JL, Morales-Canton V. Reduction of fluence to decrease pain during panretinal photocoagulation in diabetic patients. Ophthalmic Surg Lasers Imaging. 2010 Jul-Aug;41(4):432-6. doi: 10.3928/15428877-20100525-02. Epub 2010 May 28.</citation>
    <PMID>20608612</PMID>
  </reference>
  <reference>
    <citation>Mirshahi A, Lashay A, Roozbahani M, Fard MA, Molaie S, Mireshghi M, Zaferani MM. Pain score of patients undergoing single spot, short pulse laser versus conventional laser for diabetic retinopathy. Graefes Arch Clin Exp Ophthalmol. 2013 Apr;251(4):1103-7. doi: 10.1007/s00417-012-2167-5. Epub 2012 Oct 11.</citation>
    <PMID>23052718</PMID>
  </reference>
  <reference>
    <citation>Wu WC, Hsu KH, Chen TL, Hwang YS, Lin KK, Li LM, Shih CP, Lai CC. Interventions for relieving pain associated with panretinal photocoagulation: a prospective randomized trial. Eye (Lond). 2006 Jun;20(6):712-9. doi: 10.1038/sj.eye.6701989. Epub 2005 Jul 8.</citation>
    <PMID>16021194</PMID>
  </reference>
  <reference>
    <citation>Ko BW, Shim JH, Lee BR, Cho HY. Analgesic effects of tramadol during panretinal photocoagulation. Korean J Ophthalmol. 2009 Dec;23(4):273-6. doi: 10.3341/kjo.2009.23.4.273. Epub 2009 Dec 4.</citation>
    <PMID>20046687</PMID>
  </reference>
  <reference>
    <citation>Zakrzewski PA, O'Donnell HL, Lam WC. Oral versus topical diclofenac for pain prevention during panretinal photocoagulation. Ophthalmology. 2009 Jun;116(6):1168-74. doi: 10.1016/j.ophtha.2009.01.022. Epub 2009 Apr 19.</citation>
    <PMID>19376588</PMID>
  </reference>
  <reference>
    <citation>Tesha PE, Giavedoni LR, Berger AR, Altomare F, Chow DR, Navajas EV, Yoganathan P, Wong DT, Principe A. Subconjunctival lidocaine before laser treatment: a randomized trial. Ophthalmology. 2010 Sep;117(9):1810-4. doi: 10.1016/j.ophtha.2010.01.036. Epub 2010 Jun 8.</citation>
    <PMID>20570360</PMID>
  </reference>
  <reference>
    <citation>Chiu HH, Wu PC. Manual acupuncture for relieving pain associated with panretinal photocoagulation. J Altern Complement Med. 2011 Oct;17(10):915-21. doi: 10.1089/acm.2010.0082. Epub 2011 Oct 6.</citation>
    <PMID>21978192</PMID>
  </reference>
  <reference>
    <citation>Vujosevic S, Martini F, Longhin E, Convento E, Cavarzeran F, Midena E. SUBTHRESHOLD MICROPULSE YELLOW LASER VERSUS SUBTHRESHOLD MICROPULSE INFRARED LASER IN CENTER-INVOLVING DIABETIC MACULAR EDEMA: Morphologic and Functional Safety. Retina. 2015 Aug;35(8):1594-603. doi: 10.1097/IAE.0000000000000521.</citation>
    <PMID>25719988</PMID>
  </reference>
  <reference>
    <citation>Yadav NK, Jayadev C, Mohan A, Vijayan P, Battu R, Dabir S, Shetty B, Shetty R; Medscape. Subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy: safety profile and treatment outcome. Eye (Lond). 2015 Feb;29(2):258-64; quiz 265. doi: 10.1038/eye.2014.315. Epub 2015 Jan 23.</citation>
    <PMID>25613846</PMID>
  </reference>
  <reference>
    <citation>Mainster MA. Wavelength selection in macular photocoagulation. Tissue optics, thermal effects, and laser systems. Ophthalmology. 1986 Jul;93(7):952-8. doi: 10.1016/s0161-6420(86)33637-6.</citation>
    <PMID>3763141</PMID>
  </reference>
  <verification_date>December 2016</verification_date>
  <study_first_submitted>December 5, 2016</study_first_submitted>
  <study_first_submitted_qc>December 13, 2016</study_first_submitted_qc>
  <study_first_posted type="Estimate">December 16, 2016</study_first_posted>
  <last_update_submitted>December 13, 2016</last_update_submitted>
  <last_update_submitted_qc>December 13, 2016</last_update_submitted_qc>
  <last_update_posted type="Estimate">December 16, 2016</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Wills Eye</investigator_affiliation>
    <investigator_full_name>MidAtlantic Retina</investigator_full_name>
    <investigator_title>Dr. Allen Chiang, MD</investigator_title>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Retinal Diseases</mesh_term>
    <mesh_term>Diabetic Retinopathy</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>Yes</sharing_ipd>
    <ipd_description>Manuscript is under development.</ipd_description>
  </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/NCT02995629
org study id: 16-560
nct id: NCT02995629
lead sponsor: 
collaborator: 
has dmc: No
Our aim is to compare patient comfort when using the 532 nanometer (green) wavelength laser
      to the 577 nanometer (yellow) wavelength laser during pan retinal photocoagulation to treat
      patients with diabetic retinopathy. Secondary outcome measures will be power (mW) required to
      achieve gray-white retinal burns and duration of treatment.
As demonstrated in the Diabetic Retinopathy Study (DRS), panretinal photocoagulation (PRP)
      reduces the risk of severe vision loss in patients with proliferative diabetic retinopathy.
      The DRS recommended that PRP treatment consist of 1,200 - 1,600 laser burns 500 µm in size,
      one half to one burn width apart, applied to the peripheral retina in a scatter fashion. Most
      patients who undergo PRP experience discomfort/pain during the procedure. Once present, pain
      can affect the number and quality of burns delivered and can indirectly increase the number
      of sessions required to complete the therapy.This may in turn adversely affect patient
      compliance. Although retrobulbar and peribulbar blocks can provide adequate anesthesia for
      PRP, these anesthetic methods carry rare but serious risks such as retrobulbar hemorrhage.
      Previous studies have explored other ways to reduce discomfort related to PRP, including
      optimization of laser settings, oral and topical analgesics, subconjunctival anesthesia, and
      even acupuncture.

      Currently, green lasers (521 - 532 nm wavelength) are most commonly utilized for performing
      PRP in clinical practice. Yellow lasers (577 nm wavelength) have been of recent interest in
      treating diabetic macular edema with micropulse subthreshold grid photocoagulation, but have
      not been extensively studied in PRP for diabetic retinopathy. Compared to shorter wavelength
      laser, yellow laser comports high transmission through dense ocular media and less light
      scattering than shorter wavelengths which minimizes spot size and reduces thermal spread. The
      limited literature comparing green and yellow laser for PRP in diabetic retinopathy has shown
      that yellow laser requires less power to achieve a retinal burn. In theory this should
      translate into a reduction in perceived pain experienced during PRP, however a comparison of
      green and yellow lasers in this regard has not yet been directly examined and quantified.
allocation: Randomized
intervention model: Crossover Assignment
primary purpose: Treatment
masking: Single (Participant)
measure: Perceived patient pain assessment
time frame: a single time point within 2 minutes of completing laser treatment
description: Assessed using a standardized Wong-Baker faces pain scale
measure: Minimum power requirement to achieve moderate gray-white retinal burns
time frame: During treatment
measure: Time of treatment
time frame: During treatment
description: Time required to treat with each laser
arm group label: green (532 nm) laser
arm group type: Experimental
description: scatter laser indirect ophthalmoscopy pan retinal photocoagulation
arm group label: yellow (577 nm) laser
arm group type: Experimental
description: scatter laser indirect ophthalmoscopy pan retinal photocoagulation
intervention type: Procedure
intervention name: laser indirect ophthalmoscopy pan retinal photocoagulation
description: Prior to procedure, eligible patient is dilated and a topical anesthesia is administered 3 to 5 minutes prior to treatment initiation
Treatment duration is fixed at 50 minutes and power is titrated until moderate gray-white burns are achieved, avoiding long ciliary nerves
Target treatment of 250 spots
Only one eye per eligible patient randomized with regard to whether green or yellow laser utilized first
After treatment,pain assessment conducted:spot count, laser parameters and treatment duration recorded for each respective laser wavelength
arm group label: green (532 nm) laser
arm group label: yellow (577 nm) laser
other name: PRP laser
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: No
last name: Allen Chiang, MD
role: Principal Investigator
affiliation: Mid Atlantic Retina
facility: 
country: United States
citation: Photocoagulation treatment of proliferative diabetic retinopathy. Clinical application of Diabetic Retinopathy Study (DRS) findings, DRS Report Number 8. The Diabetic Retinopathy Study Research Group. Ophthalmology. 1981 Jul;88(7):583-600.
PMID: 7196564
citation: Richardson C, Waterman H. Pain relief during panretinal photocoagulation for diabetic retinopathy: a national survey. Eye (Lond). 2009 Dec;23(12):2233-7. doi: 10.1038/eye.2008.421.
PMID: 19169228
citation: Alvarez-Verduzco O, Garcia-Aguirre G, Lopez-Ramos Mde L, Vera-Rodriguez S, Guerrero-Naranjo JL, Morales-Canton V. Reduction of fluence to decrease pain during panretinal photocoagulation in diabetic patients. Ophthalmic Surg Lasers Imaging. 2010 Jul-Aug;41(4):432-6. doi: 10.3928/15428877-20100525-02. Epub 2010 May 28.
PMID: 20608612
citation: Mirshahi A, Lashay A, Roozbahani M, Fard MA, Molaie S, Mireshghi M, Zaferani MM. Pain score of patients undergoing single spot, short pulse laser versus conventional laser for diabetic retinopathy. Graefes Arch Clin Exp Ophthalmol. 2013 Apr;251(4):1103-7. doi: 10.1007/s00417-012-2167-5. Epub 2012 Oct 11.
PMID: 23052718
citation: Wu WC, Hsu KH, Chen TL, Hwang YS, Lin KK, Li LM, Shih CP, Lai CC. Interventions for relieving pain associated with panretinal photocoagulation: a prospective randomized trial. Eye (Lond). 2006 Jun;20(6):712-9. doi: 10.1038/sj.eye.6701989. Epub 2005 Jul 8.
PMID: 16021194
citation: Ko BW, Shim JH, Lee BR, Cho HY. Analgesic effects of tramadol during panretinal photocoagulation. Korean J Ophthalmol. 2009 Dec;23(4):273-6. doi: 10.3341/kjo.2009.23.4.273. Epub 2009 Dec 4.
PMID: 20046687
citation: Zakrzewski PA, O'Donnell HL, Lam WC. Oral versus topical diclofenac for pain prevention during panretinal photocoagulation. Ophthalmology. 2009 Jun;116(6):1168-74. doi: 10.1016/j.ophtha.2009.01.022. Epub 2009 Apr 19.
PMID: 19376588
citation: Tesha PE, Giavedoni LR, Berger AR, Altomare F, Chow DR, Navajas EV, Yoganathan P, Wong DT, Principe A. Subconjunctival lidocaine before laser treatment: a randomized trial. Ophthalmology. 2010 Sep;117(9):1810-4. doi: 10.1016/j.ophtha.2010.01.036. Epub 2010 Jun 8.
PMID: 20570360
citation: Chiu HH, Wu PC. Manual acupuncture for relieving pain associated with panretinal photocoagulation. J Altern Complement Med. 2011 Oct;17(10):915-21. doi: 10.1089/acm.2010.0082. Epub 2011 Oct 6.
PMID: 21978192
citation: Vujosevic S, Martini F, Longhin E, Convento E, Cavarzeran F, Midena E. SUBTHRESHOLD MICROPULSE YELLOW LASER VERSUS SUBTHRESHOLD MICROPULSE INFRARED LASER IN CENTER-INVOLVING DIABETIC MACULAR EDEMA: Morphologic and Functional Safety. Retina. 2015 Aug;35(8):1594-603. doi: 10.1097/IAE.0000000000000521.
PMID: 25719988
citation: Yadav NK, Jayadev C, Mohan A, Vijayan P, Battu R, Dabir S, Shetty B, Shetty R; Medscape. Subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy: safety profile and treatment outcome. Eye (Lond). 2015 Feb;29(2):258-64; quiz 265. doi: 10.1038/eye.2014.315. Epub 2015 Jan 23.
PMID: 25613846
citation: Mainster MA. Wavelength selection in macular photocoagulation. Tissue optics, thermal effects, and laser systems. Ophthalmology. 1986 Jul;93(7):952-8. doi: 10.1016/s0161-6420(86)33637-6.
PMID: 3763141
responsible party type: Principal Investigator
investigator affiliation: Wills Eye
investigator full name: MidAtlantic Retina
investigator title: Dr. Allen Chiang, MD
mesh term: Retinal Diseases
mesh term: Diabetic Retinopathy
sharing ipd: Yes
ipd description: Manuscript is under development.