MicroPulse Transscleral Laser Therapy and Its Short-term Impact on Ocular Surface

MicroPulse transscleral laser therapy (TLT) is proven to be effective in reducing intraocular pressure with minimal complications in either primary or secondary glaucoma. However, its impact on the human ocular surface remains unexplored. This study aims to bridge this gap by examining the clinical and histopathological effects of MicroPulse TLT on the ocular surface.

Study Overview

• Status: Completed
• Conditions: Cornea; Conjunctiva
• Intervention / Treatment: Procedure: conjunctival biopsy after micropulse transscleral laser therapy

Detailed Description

This prospective study, conducted at Mohamed Taher Maamouri University Hospital in Nabeul, Tunisia, investigates the clinical and histopathological short-term effects of MicroPulse transscleral laser therapy (TLT) on the ocular surface. The study involves 16 eyes from 15 adult patients. Participants underwent MicroPulse TLT, followed by conjunctival biopsies for the analysis of inflammation and fibrosis. Participants also benefited from ophthalmological examination and responded to the Ocular Surface Disease Index (OSDI) questionnaire before and after MicroPulse TLT.

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Tunisia
  • Nabeul, Tunisia, 8000
    • Mohamed Taher Maamouri Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age > 18 years old
• Non-controlled open-angle glaucoma despite undergoing maximal medical therapy
• Poor therapeutic adherence
• Local or general intolerance to topical treatments.

Exclusion Criteria:

• Ophthalmic or general diseases that could potentially impact the conjunctiva such as symblepharon, ocular injury, or prior eye surgery
• Pevious transscleral laser therapy applied to the same eye
• angle-closure glaucoma
• active ocular inflammation
• a non-functional eye (absence of light perception)
• scleral thinning

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: MP-TLT + conjunctival biopsy; Participants underwent MicroPulse transscleral laser therapy, followed by conjunctival biopsies for the analysis of inflammation and fibrosis.

Procedure: conjunctival biopsy after micropulse transscleral laser therapy; During MicroPulse TLT, all patients received periocular anesthesia, with an injection of 5 to 10 ml of Lidocaine (Xylocaine 5mg/ml ®) to achieve complete anesthesia. The investigators employed the 810 nm Cyclo G6® Laser in its MicroPulse® mode (Iridex Corporation, Mountain View, CA, USA) and delivered laser energy to the eye using the second-generation MicroPulse P3® probe (Iridex Corporation, Mountain View, CA, USA). The laser was calibrated to generate a power output of 2500 mW, and a MicroPulse duty cycle of 31.3%. The curved end of the probe's footplate (bunny ears) was positioned 0.5 to 1 mm away from the corneoscleral limbus, maintaining a perpendicular orientation to the eyeball. Following the laser therapy, an immediate conjunctival biopsy measuring 2 * 2 mm and avoiding the laser-treated region was performed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
conjunctival inflammation or fibrosis	histological changes of the conjunctiva according to a scale ranging from 0 to 3, with the following interpretation: Grade 0: no difference between the two samples; Grade 1: increase in inflammation / fibrosis < 33%; Grade 2: increase in inflammation / fibrosis from 33% to 66%; Grade 3: increase in inflammation / fibrosis > 66%	1 month
intraocular pression	change in intraocular pression	6 months
ocular surface disease index score	This score is calculated and ranges from 0 to 100 with the following interpretation: 0 to 12 = Normal; 13 to 22 = Mild ocular surface disease; 23 to 32 = Moderate ocular surface disease; 33 to 100 = Severe ocular surface disease	6 months

Collaborators and Investigators

• Sponsor: University Tunis El Manar

Study record dates

Study Major Dates

• Study Start (Actual): May 3, 2023
• Primary Completion (Actual): October 31, 2023
• Study Completion (Actual): October 31, 2023

Study Registration Dates

• First Submitted: March 25, 2024
• First Submitted That Met QC Criteria: April 2, 2024
• First Posted (Actual): April 9, 2024

Study Record Updates

• Last Update Posted (Actual): April 9, 2024
• Last Update Submitted That Met QC Criteria: April 2, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: inflammation; glaucoma; fibrosis; ocular surface; MicroPulse; transscleral laser therapy
• Other Study ID Numbers: 02052023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No