DSLT in Normal Tension Glaucoma (NTG) Asian Eyes

The Effectiveness of DSLT in Asian Normal Tension Glaucoma Patients

The goal of this clinical trial is to evaluate the efficacy of direct selective laser trabeculoplasty (DSLT) or laser treatment in Asian patients with normal tension glaucoma. The main question it aims to answer is:

Does the DSLT reduce intraocular pressure (IOP) and medication use in Asian NTG subjects? Participants will attend routine follow-up visits with their eye surgeon and glaucoma testing such as optical coherence tomography (OCT) imaging and visual field test(s) after the laser study treatment.

Study Overview

• Status: Not yet recruiting
• Conditions: Glaucoma; Glaucoma, Open Angle; Open Angle Glaucoma (OAG); Normal Tension Glaucoma (NTG)
• Intervention / Treatment: Device: Direct Selective Laser Trabeculoplasty (DSLT)

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ngoc Nguyen, M.D.; Phone Number: 4082723706; Email: ngocyu@hotmail.com
• Study Contact Backup: Name: Lauren Nguyen; Phone Number: 4086092569; Email: laurenhtnguyen@gmail.com

Study Locations

• United States
  • California
    • San Jose, California, United States, 95116
      • Ngoc Nguyen M.D.
      • Contact: Lauren Nguyen; Phone Number: 4086092569; Email: laurenhtnguyen@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Asian descent
• NTG diagnosis: glaucomatous optic neuropathy in patients with IOP measurements consistently lower than 21 mmHg
• Mean deviation (MD) of the visual field between 0 to -12dB
• No significant central vision loss within 5 degrees within 5th percentile
• Age ≥20 years
• NTG patients who are medically controlled on 1-3 medications and safe to wash out or IOP is still insufficient from medications and safe to washout
• Shaffer grade II or more on 3 of the 4 quadrants
• Central corneal thickness (CCT) 450-600µm
• All participants are able to provide written informed consent before participation

Exclusion Criteria:

• Angle closure glaucoma or narrow angle status post laser peripheral iridotomy (LPI), or any other open angle glaucoma excluding NTG
• History of SLT within last 2 years
• History intraocular surgery including refractive surgery, except for history of cataract surgery that has been greater than 1 year
• Patients anticipating cataract surgery during the study follow-up period
• Unable to have DSLT procedure due to pre-limbal findings
• Any presence of relevant ocular diseases including retinal disease with no confirmed cure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: DSLT Treatment Arm; Participants will receive Direct Selective Laser Trabeculoplasty (DSLT) using the BELKIN Vision Eagle device. The procedure is performed without a contact lens and delivers non-contact laser energy to the trabecular meshwork to lower intraocular pressure. All participants undergo standard pre- and post-procedure evaluations, including IOP measurements, visual field testing, and OCT imaging.

Device: Direct Selective Laser Trabeculoplasty (DSLT); Direct Selective Laser Trabeculoplasty (DSLT) is a non-contact laser procedure that delivers energy to the trabecular meshwork without the need for a gonioscopy lens. The BELKIN Vision Eagle device automatically aligns and applies laser pulses to lower intraocular pressure in subjects with normal tension glaucoma. All participants receive a single DSLT treatment followed by routine post-procedure evaluations including IOP checks, visual field testing, and OCT imaging.; Other Names: BELKIN Vision Eagle; Non-contact SLT; DSLT Laser Treatment; Direct Selective Laser Trabeculoplasty

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Intraocular Pressure (IOP)	Absolute change in washed-out intraocular pressure (IOP) at 12 months compared to washed-out baseline IOP. Following a 6-week washout at baseline and again at month 11, IOP will be measured using standard tonometry to assess the effect of Direct Selective Laser Trabeculoplasty (DSLT) on pressure reduction.	12 months post procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Glaucoma Medications Reduced	Change in the number of topical glaucoma medications required to control intraocular pressure at 11 months compared to baseline, to evaluate whether DSLT decreases medication burden.	12 months post-procedure
Proportion of Patients Who Are Medication-Free	Proportion of participants who require zero topical glaucoma medications at 11 months after DSLT treatment.	12 months post-procedure

Collaborators and Investigators

• Sponsor: Ngoc Nguyen Inc.
• Collaborators: Alcon Research

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2026
• Primary Completion (Estimated): January 31, 2028
• Study Completion (Estimated): March 31, 2028

Study Registration Dates

• First Submitted: December 9, 2025
• First Submitted That Met QC Criteria: December 20, 2025
• First Posted (Actual): December 24, 2025

Study Record Updates

• Last Update Posted (Actual): December 24, 2025
• Last Update Submitted That Met QC Criteria: December 20, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Intraocular pressure; Glaucoma; Normal Tension Glaucoma; NTG; DSLT; Direct Selective Laser Trabeculoplasty; BELKIN Vision Eagle; Glaucoma laser treatment; Asian glaucoma; SLT alternative; Glaucoma medications reduction
• Additional Relevant MeSH Terms: Eye Diseases; Optic Nerve Diseases; Ocular Hypertension; Glaucoma; Glaucoma, Open-Angle; Low Tension Glaucoma
• Other Study ID Numbers: NTG_DSLT-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: There is no plan to share individual participant data (IPD) for this study. The sample size is small and sharing de-identified datasets may not adequately protect participant privacy.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No