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

Angle Closure Glaucoma Clinical Trial

Official title:

Randomized Clinical Trial Comparing Neodynium:Ytrium-aluminium-garnet (Nd:YAG) Laser and Sequential Double Frequency YAG-Nd:YAG Laser Iridotomy in Patients With Dark Iris

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02474238
• Other study ID #: EC-58-093-02-1
• Status: Completed
• Phase: N/A
• Start date: May 2015
• Est. completion date: August 2018

Study information

• Verified date: August 2018
• Source: Prince of Songkla University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 82
• Est. completion date: August 2018
• Est. primary completion date: August 2018
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

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

Related Conditions & MeSH terms

• Angle Closure Glaucoma
• Glaucoma, Angle-Closure

Intervention

Device:
• 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.
• The pure Nd:YAG laser technique
By using 'the pure Nd:YAG laser' to make a complete perforation on iris.

Locations

Country	Name	City	State
Thailand	Weerawat Kiddee	Hat Yai	Songkhla

Sponsors (1)

Lead Sponsor	Collaborator
Prince of Songkla University

Country where clinical trial is conducted

Thailand, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Laser energy	Total energy used to create patency on the iris	1-hour
Secondary	Bleeding	iris bleeding immediate after laser reported as Yes or No	1-hour
Secondary	Corneal endothelial cell count	Corneal endothelial cell count directly over the area of laser	12-month
Secondary	Central corneal thickness	Central corneal thickness	12-month
Secondary	Patency of iridotomy	Iridotomy patency is confirmed objectively reported as yes or no	12-month
Secondary	Intraocular pressure spike	Intraocular pressure spike if present mean that IOP evelation of at least 8mmHg from baseline intraocular pressure	1-hour