Short-pulse Subthreshold vs Infrared Micropulse for Diabetic Macular Edema

Not Applicable

Completed

• Conditions: Diabetic Macular Edema
• Interventions: Procedure: Macular Laser

• Registration Number: NCT04505306
• Lead Sponsor: Moorfields Eye Hospital Centre Abu Dhabi

Brief Summary

When applied according to manufacturer recommendations, short-pulse system may yield more temporary reduction in edema while infrared micropulse system may yield slightly better functional outcomes.

Detailed Description

Purpose: To assess both anatomic and functional outcomes between short-pulse continuous wavelength and infrared micropulse lasers in the treatment of DME.

Materials and Methods: A prospective interventional study from tertiary care eye hospital - King Khaled Eye Specialist Hospital (Riyadh, Saudi Arabia). Patients with center-involving diabetic macular edema were treated with subthreshold laser therapy. Patients in the micropulse group were treated with the 810-nm diode micropulse scanning laser TxCell™ (IRIDEX Corporation, Mountain View, CA, USA). Laser was applied according to manufacturer recommendations for MicroPulseTM in a confluent mode (low intensity/high density) to the entire area of the macular edema. Patients in the short-pulse group were treated with grid pattern laser with 20ms pulse PASCAL laser 532nm (TopCon Medical Laser Systems, Tokyo, Japan) with EndPoint algorithm, which was either 30% or 50% of testing burn. Main outcome measures included best-corrected visual acuity (BCVA) and foveal thickness at baseline and the last follow-up visit.

Study Timeline

• Study Start: 2015-01-01
• Primary Completion: 2017-01-01
• Study Completion: 2017-01-01
• Status Verified: 2020-08
• Study First Submitted: 2020-08-02
• Study First Submitted QC: 2020-08-05
• Last Update Submitted: 2020-08-05
• Study First Posted: 2020-08-10
• Last Update Posted: 2020-08-10

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 113

Inclusion Criteria

• center-involving clinically significant macular edema due to diabetic retinopathy (>300 microns)
• clear ocular media
• ETDRS visual acuity >29 letters (Snellen equivalent of 20/150) or better
• treatment naïve eyes or previously treated with antiangiogenic intravitreal agent(s) more than 6 months ago to allow for long wash-out period

Exclusion Criteria

• non-center involving diabetic macular edema
• previous retinal laser or surgery
• intravitreal steroid use
• any condition that may be associated with a risk of macular edema such as age-related macular degeneration, retinal vein occlusion, vitreomacular traction, epiretinal membrane and others.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Micropulse Laser	Macular Laser	Patients in the STMP group were treated with the 810-nm diode micropulse scanning laser TxCell™ (IRIDEX Corporation, Mountain View, CA, USA) at 15% duty cycle.
Subthreshold Laser 30%	Macular Laser	Patients in the SPCW group were treated with grid pattern laser with 20ms pulse PASCAL laser 532nm (TopCon Medical Laser Systems, Tokyo, Japan) with 30% EndPoint algorithm.
Subtreshold Laser 50%	Macular Laser	Patients in the SPCW group were treated with grid pattern laser with 20ms pulse PASCAL laser 532nm (TopCon Medical Laser Systems, Tokyo, Japan) with 50% EndPoint algorithm.

Primary Outcome Measures

Name	Time	Method
Best corrected visual acuity	6 months	ETDRS visual acuity charts
Central foveal thickness	6 months	All patients had central retinal thickness measurement using spectral-domain optical coherence tomography (SD-OCT)(Spectralis, Heidelberg Engineering, Heidelberg, Germany). The SD-OCT B-scan was based on the Spectralis macular raster consisting of 19 horizontals 6 millimeter line scans and a real-time eye tracking system.

Trial Locations

Locations (1)

Moorfields Eye Hospital Centre; 🇦🇪 Abu Dhabi, United Arab Emirates