Optical Coherence Tomography Quantitative Analysis of Changes in Anterior Chamber After Laser Peripheral Lridotomy

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to analysis changes in anterior segment morphology after laser peripheral lrldotomy measured by optical coherence tomography, and to evaluate treatment effectiveness

Detailed Description
-----------------
In the study ,primary angle closure(PAC) and primary angle closure glaucoma (PACG) will be recruited. Anterior segment optical coherence tomography images captured before and after laser peripheral iridotomy will be analysed to provide objective and reproducible quantification of anterior segment biometric parameters.The outcomes can provide useful information for clinical strategies in the treatment and management of pathology related to angle closure.

Conditions
-----------------
Primary Angle Closure Glaucoma

Intervention / Treatment
-----------------
* Procedure: Laserex Tango Nd:YAG, Ellex-SuperQ Medical, Australia


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: 1 .The gonioscopy or UBM examination has confirmed the diagnosis of PACS or PAC 2. Intraocular pressure within 10 to 21 mmHg ，C/D≤0.6 3. Visual field is normal or only show paracentral scotoma 4. Vision or corrected visual acuity ≥0.8 5. Refractive degree no more than 200D 6. Exclude other ocular and systemic diseases - Exclusion Criteria: Corneal macula and other corneal diseases, ocular surface disease or corneal edema Iridocyclitis Ocular trauma and intraocular operation history No fixationFundus lesions such as diabetic retinopathy or retinal detachment No fixation Ocular or systemic application of cortical steroids -

Ages Eligible for Study
-----------------
Minimum Age: 30 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: laser peripheral iridotomy<br>Laser peripheral iridotomy (LPI) is widely regarded as the first-line intervention for either acute or chronic types of angle-closure glaucoma in early stage ,which relieves pupil block and thus flattening the iris contour and widening the drainage angle,performd by Nd.YAG LASER | Procedure: Laserex Tango Nd:YAG, Ellex-SuperQ Medical, Australia<br>* All the patients will be achieved with pilocarpine 1% for pupil constriction, laser peripheral iridotomy(LPI) is performed using the ophthalmic neodymium: yttrium aluminium garnet laser (Laserex Tango Nd:YAG, Ellex-SuperQ Medical, Australia) and an VOLK iridotomy contact lens. After LPI, patients will be given topical prednisolone acetate 0.1% for 7 days.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in anterior chamber after LPI at 1 month |  | 1month |