The Effects of DSLT and SLT on the Corneal Endothelium: A GLAUrious Trial Sub-Study

NCT04758598 | Completed

• 1 other identifier: 2020-01
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The objective of this study is to compare the long-term (6 months) effects of Direct Selective Laser Trabeculoplasty (DSLT) treatment and SLT (Selective Laser Trabeculoplasty) treatment on corneal endothelial cell counts and corneal thickness.

Conditions

Open Angle Glaucoma

Outcome Measures

Primary Outcomes (2)

• Difference between the mean baseline and 6 month central corneal thickness, DSLT vs SLT

  Central corneal thickness will be assessed by pachymetry

  6 months

• Difference between the mean baseline and 6 month corneal endothelial cell count, DSLT vs SLT

  Corneal endothelial cell count will be assessed with specular microscopy

  6 months

Study Arms (2)

Direct Selective Laser Trabeculoplasty (DSLT)

EXPERIMENTAL

Direct Selective Laser Trabeculoplasty (DSLT): employs frequency-doubled, Q-switched Nd:YAG laser with a wavelength of 532 nm. During the procedure, a laser beam targets the trabecular meshwork (TM) - to improve intraocular fluid outflow. The laser beam is delivered in short nanosecond pulses and the selective cellular effect occurs at the pigmented cells of the TM. This increases the permeability of the TM endothelial cells and thereby increases outflow, resulting in reductions in IOP. In contrast to SLT, the DSLT treatment directs the laser beam directly through the sclera around the limbus without the need for a delivery device (gonioscope lens). Laser treatment lasts for about 2 seconds with about 120 laser shots delivered to the sclera around the limbus.

Device: Direct Selective Laser Trabeculoplasty (DSLT)

Selective Laser Trabeculoplasty (SLT)

ACTIVE COMPARATOR

SLT employs frequency doubled Q switched Nd:YAG laser with a wavelength of 532 nm. It is delivered in short nano second pulses and the resulting selective effect to the pigmented cells of the TM, leaving the surrounding non-pigmented cells unaffected. This increases the permeability of the TM endothelial cells and can assist in increasing outflow and hence result in reductions in IOP. The procedure lasts approximately 10 minutes, with delivering 100 separate laser beams through a manually rotated mirrored lens (gonioscope), involving prolonged contact with the participant's eye. This treatment is applied on the cornea through a gonioscopic lens which is used to direct the laser beam to the desired location - the TM (360 degrees of treatment area).

Device: Selective Laser Trabeculoplasty (SLT)

Interventions

Direct Selective Laser Trabeculoplasty (DSLT) DEVICE

DSLT employs frequency-doubled, Q-switched Nd:YAG laser with a wavelength of 532 nm. During the procedure, a laser beam targets the trabecular meshwork (TM) - to improve intraocular fluid outflow. The laser beam is delivered in short nanosecond pulses and the selective cellular effect occurs at the pigmented cells of the TM. This increases the permeability of the TM endothelial cells and thereby increases outflow, resulting in reductions in IOP. In contrast to SLT, the DSLT treatment directs the laser beam directly through the sclera around the limbus without the need for a delivery device (gonioscope lens). Laser treatment lasts for about 2 seconds with about 120 laser shots delivered to the sclera around the limbus.

Direct Selective Laser Trabeculoplasty (DSLT)

Selective Laser Trabeculoplasty (SLT) DEVICE

SLT employs frequency doubled Q switched Nd:YAG laser with a wavelength of 532 nm. It is delivered in short nano second pulses and the resulting selective effect to the pigmented cells of the TM, leaving the surrounding non-pigmented cells unaffected. This increases the permeability of the TM endothelial cells and can assist in increasing outflow and hence result in reductions in IOP. The procedure lasts approximately 10 minutes, with delivering 100 separate laser beams through a manually rotated mirrored lens (gonioscope), involving prolonged contact with the participant's eye. This treatment is applied on the cornea through a gonioscopic lens which is used to direct the laser beam to the desired location - the TM (360 degrees of treatment area).

Selective Laser Trabeculoplasty (SLT)

Eligibility Criteria

• Age: 40 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 40 years or older, with visual acuity \> 6/60 in both eyes
• Open angle glaucoma including exfoliative or pigmentary glaucoma or ocular hypertension.
• IOP ≥ 22mmHg or ≤35mmHg (after washout of any IOP-lowering medications) for participants with open angle glaucoma or IOP ≥ 24mmHg to ≤35mmHg (after washout of any IOP-lowering medications) for participants with ocular hypertension
• Gonioscopically visible scleral spur for 360 degrees without indentation
• Ability to visualize the peri-limbal sclera for 360 degrees (using a speculum)
• Willing and able to participate in the 12-month study, to comply with the study procedures and to adhere to the follow-up schedule.
• Participant capable of giving informed consent

You may not qualify if:

• Contraindications to conventional laser trabeculoplasty (e.g. corneal abnormalities etc.)
• Angle Closure Glaucoma
• Congenital or developmental glaucoma
• Secondary glaucoma except exfoliative or pigmentary glaucoma
• Inability to conduct a reliable visual field (defined as fixation losses, false positives or false negatives greater than 33%)
• Presence of any Peripheral Anterior Synechiae (PAS) in the study eye
• Any of the following visual field findings using the Humphrey visual field analyzer the SITA-standard 24-2 program:
• A visual field MD of worse than -12dB
• Greater than or equal to 75% of points depressed below the 5% level and greater than or equal to 50% of points depressed below the 1% level on the PD plot
• At least 50% of points (i.e., 2 or more) within the central 5 degrees with a sensitivity ≤0dB on the decibel plot
• Points within the central 5 degrees of fixation with a sensitivity \<15 dB in both hemifields on the decibel plot
• A visual field MD of worse than -12dB in the fellow eye
• Cup:Disc Ratio more than 0.8
• More than three hypotensive medications required (combination drops are considered 2 medications)
• Prior incisional or laser glaucoma surgery (including previous SLT) in the study eye

Sponsors & Collaborators

• BelkinVision: lead

Study Sites (1)

Akhali Mzera Eye Clinic

Tbilisi, Georgia

Location

MeSH Terms

Conditions

Glaucoma, Open-Angle

Condition Hierarchy (Ancestors)

Glaucoma; Ocular Hypertension; Eye Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: DSLT treatment vs. SLT treatment

Study Record Dates

• First Submitted: February 11, 2021
• First Posted: February 17, 2021
• Study Start: March 1, 2021
• Primary Completion: April 15, 2022
• Study Completion: May 6, 2022
• Last Updated: January 17, 2023

Record last verified: 2021-02

Locations

GE (1)