Micropulse 577 nm Laser Photocoagulation Versus Conventional 532 nm Laser Photocoagulation for Diabetic Macular Oedema (UMDMO)

The recruitment status of this study is unknown because the information has not been verified recently.
Verified January 2010 by University of Malaya.
Recruitment status was  Recruiting
Sponsor:
Information provided by:
University of Malaya
ClinicalTrials.gov Identifier:
NCT01045239
First received: January 7, 2010
Last updated: NA
Last verified: January 2010
History: No changes posted
  Purpose

The purpose of this study is to determine whether the new micropulse 577 nm yellow laser is a better treatment option compared to the conventional 532 nm green laser for diabetic macular edema.


Condition Intervention Phase
Diabetic Macular Edema
Device: Micropulse 577 nm yellow diode laser
Device: 532 nm green diode laser
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Randomized, Controlled Trial Comparing Micropulse 577 nm Laser Photocoagulation And Conventional 532 nm Laser Photocoagulation for Diabetic Macular Oedema

Resource links provided by NLM:


Further study details as provided by University of Malaya:

Primary Outcome Measures:
  • Best corrected visual acuity by logarithm of the minimum angle of resolution (LogMAR) [ Time Frame: 1 year ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Macular thickness measured by optical coherence tomography (OCT) [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  • Photocoagulation scars on fundus photograph [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]

Estimated Enrollment: 100
Study Start Date: October 2009
Estimated Study Completion Date: January 2012
Estimated Primary Completion Date: October 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Micropulse 577 nm yellow diode laser Device: Micropulse 577 nm yellow diode laser
Laser administered at beginning of study and may be repeated at 16 weeks if needed
Other Name: Quantel Supra 577nm laser
Active Comparator: 532 nm green diode laser Device: 532 nm green diode laser
Laser administered at beginning of study and may be repeated at 16 weeks if needed

Detailed Description:

Diabetes mellitus (DM) is a serious debilitating and deadly disease causing significant mortality and morbidity globally. Diabetic macular oedema is the most common cause of visual loss in the working population.

In 1985, the Early Treatment Diabetic Retinopathy Study (ETDRS) demonstrated that focal (direct/grid) laser photocoagulation reduces moderate vision loss from diabetic macular oedema (DMO) by 50% or more. However, further studies have shown that photocoagulation can eventually result in complications leading to loss of central vision and decreased colour vision. Thus, many newer laser machines that claim to reduce the rate of complications have been developed over the years.

In this project, we plan to evaluate the usage of the micropulse 577 nm laser, which is a yellow light laser, and compare it to the conventional 532 nm green laser that is widely used. The 577 nm laser has a high affinity for oxyhemoglobin, a slightly lower affinity for melanin and almost no affinity for macular xanthophylls, as shown in the graph below.22,23,24,25 The yellow 577 nm light also scatters very little and does not cause photochemical reactions in the tissues.

The theoretical advantage of using the micropulse 577 nm yellow laser would be the reduced energy requirement to obtain the same results as with green 532 nm. This leads to less retinal toxicity and damage due to reduced absorption by the xanthophylls. Our aim in this project is to observe whether the theoretical advantage translates to a more effective treatment in reality.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Diabetes mellitus (type 1 or 2)
  • Diabetic macular edema in study eye associated to diabetic retinopathy
  • Diffuse macular edema defined as macular thickening determined by biomicroscopy, OCT and/or fluorescein angiography.
  • Best corrected visual acuity between 34 (20/200) and 68 letters (20/50).
  • Macular thickness greater than 300 mcm on OCT.

Exclusion Criteria:

  • Significant renal disease, defined as a history of chronic renal failure requiring dialysis or kidney transplant.
  • A condition that, in the opinion of the investigator, would preclude participation in the study (e.g., unstable medical status including blood pressure, cardiovascular disease, and glycemic control).
  • Blood pressure > 180/110 (systolic above 180 OR diastolic above 110).
  • Subject is expecting to move out of the area of the clinical center to an area not covered by another clinical center during the next 6 months.

The following exclusions apply to the study eye only (i.e., they may be present for the nonstudy eye):

  • Macular edema is considered to be due to a cause other than diabetic macular edema.
  • Presence of vitreomacular traction.
  • Concurrent proliferative diabetic retinopathy.
  • An ocular condition is present such that, in the opinion of the investigator, visual acuity loss would not improve from resolution of macular edema (e.g., foveal atrophy, pigment abnormalities, dense subfoveal hard exudates, significant macular ischemia, nonretinal condition).
  • An ocular condition is present (other than diabetes) that, in the opinion of the investigator, might affect macular edema or alter visual acuity during the course of the study (e.g., vein occlusion, uveitis epiretinal membrane, or other ocular inflammatory disease, neovascular glaucoma, etc.).
  • Substantial cataract that, in the opinion of the investigator, is likely to be decreasing visual acuity by 3 lines or more (i.e., cataract would be reducing acuity to 20/40 or worse if eye was otherwise normal).
  • History of treatment for DME at any time in the past 4 months (such as focal/grid macular photocoagulation, intravitreal or peribulbar corticosteroids, anti-VEGF drugs, or any other treatment).
  • History of panretinal (scatter) photocoagulation (PRP) prior to enrollment or anticipated to be performed within next 6 months.
  • History of major ocular surgery (including vitrectomy, cataract extraction, scleral buckle, any intraocular surgery, etc.) within prior 12 months or anticipated within the next 6 months.
  • History of YAG capsulotomy performed within 2 months prior to enrollment.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01045239

Contacts
Contact: Linda Ong, MBBS +603-79494422 ext 2060 lindaong@hotmail.com

Locations
Malaysia
University Malaya Eye Research Centre Recruiting
Kuala Lumpur, Malaysia, 59100
Contact: Ng Joanne, BSc    +603-79494422 ext 2060    joanne.npj@gmail.com   
Sponsors and Collaborators
University of Malaya
Investigators
Principal Investigator: Kenneth C Fong, FRCOphth University of Malaya Eye Research Centre
Principal Investigator: Tajunisah Iqbal, FRCS University of Malaya Eye Research Centre
  More Information

No publications provided

Responsible Party: Assoc Prof Kenneth Choong-Sian Fong, University Malaya Eye Research Centre
ClinicalTrials.gov Identifier: NCT01045239     History of Changes
Other Study ID Numbers: UMERC001
Study First Received: January 7, 2010
Last Updated: January 7, 2010
Health Authority: Malaysia: Ministry of Health

Keywords provided by University of Malaya:
Diabetic macular edema
Diabetic macular oedema
micropulse laser
laser treatment
macular thickness

Additional relevant MeSH terms:
Edema
Macular Edema
Signs and Symptoms
Macular Degeneration
Retinal Degeneration
Retinal Diseases
Eye Diseases

ClinicalTrials.gov processed this record on April 17, 2014