Comparing Nd:YAG Laser and Sequential Double Frequency YAG-Nd:YAG Laser Iridotomy

Not Applicable

Completed

• Conditions: Angle Closure Glaucoma
• Interventions: Device: The sequential technique

• Registration Number: NCT02474238
• Lead Sponsor: Prince of Songkla University

Brief Summary

No single type of laser or set of laser parameters is appropriate for all type of irides. Pure Nd:YAG laser iridotomy is very effective in the light color irides. It was considered as the gold standard for iridotomy. It, however, is less effective and causes some complication such as iris hemorrhage especially in patients with dark iris.

Detailed Description

By using the double frequency YAG to make the initial bore and the Nd:YAG laser to complete the perforation, the technique should be able to effectively combine most of the advantages of both lasers whilst avoiding their disadvantages. It is possibly the ideal iridotomy technique to use in the Asian irides. The investigators aim to study the energy use for laser iridotomy comparing between the two techniques as well as objectively measure the variables associated with complications.

Study Timeline

• Study Start: 2015-05
• Study First Submitted: 2015-06-11
• Study First Submitted QC: 2015-06-12
• Study First Posted: 2015-06-17
• Status Verified: 2018-08
• Primary Completion: 2018-08
• Study Completion: 2018-08
• Last Update Submitted: 2018-08-24
• Last Update Posted: 2018-08-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 82

Inclusion Criteria

• Patient in need to have a laser iridotomy

  • primary angle closure glaucoma or
  • primary angle closure or
  • primary angle closure suspect (needed repeated pupil dilation) or
  • fellow eyes of acute angle closure crisis, and

• Age of at least 18 years, and

• Dark iris patients (only black and dark brown color)

Exclusion Criteria

• Eye with acute angle closure crisis
• Active conjunctiva or corneal infection or inflammation
• Active anterior uveitis
• History of any prior laser treatment
• History intraocular surgery
• Eye with corneal scar
• Corneal haziness obscure iridotomy site
• Endothelial cell count less than 1000 cells/mm2 (pre-laser)
• Iris color other than black or dark brown
• Inability to sit at the slit lamp to have laser done

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
The sequential technique	The sequential technique	By using the double frequency YAG laser to make the initial bore and the Nd:YAG laser to complete the perforation on iris.

Primary Outcome Measures

Name	Time	Method
Laser energy	1-hour	Total energy used to create patency on the iris

Secondary Outcome Measures

Name	Time	Method
Bleeding	1-hour	iris bleeding immediate after laser reported as Yes or No
Corneal endothelial cell count	12-month	Corneal endothelial cell count directly over the area of laser
Central corneal thickness	12-month	Central corneal thickness
Patency of iridotomy	12-month	Iridotomy patency is confirmed objectively reported as yes or no
Intraocular pressure spike	1-hour	Intraocular pressure spike if present mean that IOP evelation of at least 8mmHg from baseline intraocular pressure

Trial Locations

Locations (1)

Weerawat Kiddee; 🇹🇭 Hat Yai, Songkhla, Thailand