Laser Iridotomy Versus Phacoemulsification in Acute Angle Closure
|First Received Date ICMJE||July 7, 2006|
|Last Updated Date||October 23, 2006|
|Start Date ICMJE||October 2001|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||Complete list of historical versions of study NCT00350428 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Laser Iridotomy Versus Phacoemulsification in Acute Angle Closure|
|Official Title ICMJE||Angle Closure: Laser Iridotomy Versus Phacoemulsification Study (ACLIPS)- A Study of Acute Primary Angle Closure Glaucoma Comparing Two Treatment Modalities: Laser Peripheral vs Phacoemulsification With Posterior Intraocular Lens Implant|
This is a randomised controlled clinical trial to compare laser peripheral iridotomy (LPI) and primary phacoemulsification with intra-ocular lens implantation (phaco/IOL) in the treatment of acute primary angle-closure glaucoma (APACG). Following successful medical lowering of raised intra-ocular pressure (IOP) and control of intraocular inflammation, patients presenting to Singapore National Eye Centre and Singapore General Hospital with acute primary angle-closure glaucoma who meet the eligibility are randomised to one of the two treatment arms: laser peripheral iridotomy and primary phacoemulsification with intra-ocular lens implantation. These patients will be monitored closely for 2 years post-operatively.
The objective of this study is to conduct a randomised controlled clinical trial to compare LPI and primary phacol/IOL in the treatment of APACG.
The specific aim is to compare long-term IOP control in patients who undergo LPI with patients who undergo primary phaco/IOL. At the same time the following will be studied.
Initial Medical Treatment
Patients with APACG will be treated initially for the acute attack with medical treatment. The initial treatment is standardized to the following:
Response to Initial Treatment and Evaluation of Cataract
Patients are divided into 2 categories based on IOP after 24 hours of initiation of medical treatment: (a) APACG with IOP £ 30 mmHg (b) APACG with IOP > 30 mmHg.
Patients with IOP £ 30 mmHg are evaluated clinically for the presence of cataract and further divided into those with cataract and those without cataract. Patients with cataract are defined as those with best corrected visual acuity equal or less than 6/15 due to lens opacity in the opinion of a consultant grade ophthalmologist.
Note: Eyes with intumescent cataract (phacomorphic glaucoma), subluxated lens or anterior chamber depth differing by more than 0.3 mm are excluded.
Eligible patients with informed consent are randomised.
Laser Peripheral Iridotomy
Phacoemulsification with Intra-ocular Lens Implantation
IOP Lowering Medication
With regard to the determination of endpoints IOP evaluation will be considered from post-operative week 3 onward. This is to allow for treatment of short-term surgery related IOP fluctuation.
During the follow up period, if a rise of IOP occurs, i.e. IOP is between 22 to 24 mmHg on two occasions within one month or IOP ³ 25 mmHg on one occasion, IOP lowering medication will be started.
Post operation visit Window period
1st week ± 2 days 3rd week ± 5 days 6th week ± 7 days 3rd month ± 2 weeks 6th month to 2nd year ± 3 weeks
At the completion of the trial patient will receive normal clinical follow up of 4-6 monthly thereafter whilst the data will not be collected for this study.
The primary objective of the study is to compare IOP control between these two treatment groups.
Sample Size Calculation:
The primary objective of the study is to compare long-term intra-ocular pressure (IOP) control between the two groups.
The proportion of the subjects whose IOP are not successfully controlled in the LPI group can be estimated as 60% (Aung T 2001). And the proportion of the subjects whose IOP are not successfully controlled in the phacoemulsification with intra-ocular lens implant group is about 20% under clinical estimation. Hence, the study needs a sample size of 70 patients (Machin, Campbell, Fayers & Pinol, 1997), 35 in each group. This will be sufficient to detect a 60% vs. 20% of proportion of the subjects who develop increasing IOP between two groups with a two-sided test with a power 90% while the significance level is controlled at 5%.
Statistical Analysis Plan
All statistical analysis will be carried out on an intention-to-treat basis. In the event of lost to follow-up, patients will still be included in the analysis for the duration that they are observed, and the last IOP which is assessed before lost to follow-up will be used for data analysis.
To compare long-term IOP control between two treatments, Pearson χ2 test or Fisher’s exact test will be used. The evaluation of the incidence of recurrence of an acute attack in eyes with APACG will be carried out using Fisher’s exact test. Logistic regression will be carried out to adjust for relevant covariates.
The time interval for the subsequent increase in IOP to occur after LPI or phacol/IOL is to be recorded. Kaplan-Meier life table analysis can be applied to assess the survival time (failure being defined as any need for further glaucoma treatment) of two groups, and Log rank test will be used to compare the two survival curves. In addition, The Cox regression will be used to adjust for covariates where applicable.
An interim statistical analysis will be carried out after all patients have completed 6 months follow-up.
|Study Type ICMJE||Interventional|
|Study Phase||Not Provided|
|Study Design ICMJE||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
|Condition ICMJE||Angle Closure Glaucoma|
|Intervention ICMJE||Procedure: Laser Preipheral Iridotomy and phacoemulsification|
|Study Arm (s)||Not Provided|
|Publications *||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Completion Date||October 2007|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Ages||18 Years and older|
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||Singapore|
|NCT Number ICMJE||NCT00350428|
|Other Study ID Numbers ICMJE||R221/13/2001, SQGL05|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||Singapore National Eye Centre|
|Collaborators ICMJE||Not Provided|
|Information Provided By||Singapore National Eye Centre|
|Verification Date||October 2004|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP