Comparison of Outcome and Effectiveness Between Micropulse Diode Laser Cyclophotocoagulation and Cyclocryoablation in Treatment of Refractory Glaucoma

Study Overview
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Brief Summary
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laucoma having bad prognosis after maximally tolerated medication,glaucoma that fails after filtering operations, neovascular glaucoma, glaucoma following vitrectomy and glaucoma secondary to uveitis etc. is collectively termed as refractory glaucoma. For such glaucoma patients, cyclodestructive procedures are often used to reduce IOP, as well as to relieve ocular and periocular pain. Recently,diode laser transscleral cyclophotocoagulation has proved to be an effective method for the treatment of refractory glaucoma and it has become a standard treatment for refractory glaucoma.(Yu, Q., Liang, Y., Ji, F. and Yuan, Z.,et al 2020. ) In previous articles, little is known about the long-term outcomes of micropulse diode laser cyclophotocoagulation and cyclocryotherapy. Discrepancies in the results of several large observational analyses have introduced further ambiguity on the role of micropulse diode laser cyclophotocoagulation and cyclocryotherapy.The mechanism of transcleral cyclophotocoagulation IOP lowering in refractory glaucoma is not well understood. In this study, we perform cyclocryoablation and micropulse diode laser cyclophotocoagulation in patients with refractory glaucoma and report the outcomes / mechanism of IOP control using this new surgical paradigm. The objective of our project is to assess the end result and outcome of the role of micropulse diode laser cyclophotocoagulation and cyclocryotherapy.We aim to evaluate the comparison between micropulse diode laser cyclophotocoagulation and cyclocryotherapy. Only those subjects will be recruited who provide written informed consent. Patients are diagnosed on bases of tonometry, gonioscopy, ophthalmoscopy, perimetry. Patients' age, gender, type of glaucoma, number of diode laser treatment sessions, postoperative complications, number of hypotensive medications required to control IOP, and best corrected visual acuity (BCVA) will be evaluated. The criteria for success will be defined as postoperative IOP <21 mmHg or >20% decrease in IOP with or without additional medical treatment.

Official Title
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Comparison of Outcome and Effectiveness Between Micropulse Diode Laser Cyclophotocoagulation and Cyclocryoablation in Treatment of Refractory Glaucoma

Conditions
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Treatment of Refractory Glaucoma

Intervention / Treatment
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* Procedure: Micropulse diode laser cyclophotocoagulation in treatment of refractory Glaucoma
* Procedure: Cyclocryoablation in treatment of refractory Glaucoma


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Positive diagnosis of refractory glaucoma Poor visual acuity: Hand movements or less Age ≥ 18 years Intraocular pressure ≥ 21 mmHg Signed informed consent Exclusion Criteria: Eye surgery performed over the last 3 months Eye inflammation

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Treatment of refractory glaucoma using Micropulse diode laser cyclophotocoagulation<br> | Procedure: Micropulse diode laser cyclophotocoagulation in treatment of refractory Glaucoma<br>* Treatment of refractory Glaucoma by Micropulse diode laser cyclophotocoagulation<br>|
| Active Comparator: Treatment of refractory glaucoma using cyclocryoablation<br> | Procedure: Cyclocryoablation in treatment of refractory Glaucoma<br>* Treatment of refractory Glaucoma by cyclocryoablation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative complications | Hypotony, Fibrinous uveitis, Cystoid macular edema | 1 year | 
| Reduced IOP | Reduction in IOP to less than 21 mmHg medications required to control IOP | 1 year | 
| Decrease in number of hypotensive drugs |  | 1 year |