Angle Closure Glaucoma
Conditions
Keywords
Iridotomy
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.
Interventions
DEVICEThe 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.
DEVICEThe pure Nd:YAG laser technique
By using 'the pure Nd:YAG laser' to make a complete perforation on iris.
Sponsors
Prince of Songkla University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Laser energy | 1-hour | Total energy used to create patency on the iris |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 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 |
Countries
Thailand
Outcome results
None listed