Conditions: Posterior Capsule Opacification Ocular Hypertension
Keywords: Nd-YAG capsulotomy ocular hypertension brimonidine brinzolamide
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 79
Healthy volunteers: no

Brief summary:
To compare the efficacy of a Brinzolamide/Brimonidine fixed combination (FC) with Brimonidine 0.2% in preventing intraocular pressure (IOP) elevations after neodymium: yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy.

Detailed description:
In this prospective, randomized, double masked clinical trial, patients scheduled to undergo Nd:YAG laser posterior capsulotomy for posterior capsule opacification are randomized in 3 groups. The Brimonidine group receives 1 drop of Brimonidine 0.2%. The Brinzolamide/Brimonidine group receives 1 drop of Brinzolamide 1%/Brimonidine 0.2% fixed combination. The Control group receives artificial tears. All groups are administered a single drop instillation, approximately one hour before Nd:YAG application. Intraocular pressure measurements are performed before treatment (baseline) and at the 1, 3, 24 hours and 1 week post treatment.

Dexamethasone ophthalmic drops are prescribed q.i.d. for one week after the procedure.

Arms:
arm 1: 1 drop of Brinzolamide/Brimonidine FC 1 hour before capsulotomy arm 2: 1 drop of Brimonidine 0.2% 1 hour before Nd-YAG capsulotomy arm 3: 1 drop of artificial tears 1 hour before Nd-YAG capsulotomy

Interventions: intervention 1: Brinzolamide/Brimonidine FC intervention 2: Brimonidine 0.2% intervention 3: Artificial tears
Intervention descriptions: intervention 1: 1 drop of Brinzolamide/Brimonidine FC 1 hour before capsulotomy intervention 2: 1 drop of Brimonidine 0.2% 1 hour before Nd-YAG capsulotomy intervention 3: 1 drop of artificial tears 1 hour before Nd-YAG capsulotomy

Protocol document:
Prot_SAP_000.pdf: 
Brinzolamide/Brimonidine Combination vs Brimonidine 0.2% in the Prevention of IOP Rise 
After Nd-YAG Laser Capsulotomy  
 
NCT03192826  
 
24 April 2016  
 
Study protocol  
This prospective, randomized, double masked comparative study comprised 79 eyes of equal 
consecutive patients treated with Nd:YAG laser posterior capsulotomy due to PCO after 
uneventful phacoemulsification cataract extraction with implantation of posterior chamber 
intraocular lenses (IOL-PC). The research was approved by the Institutional Review Board, 
and adhered to the tenets of the Declaration of Helsinki. Written informed consent was 
obtained from all participants. Patients were randomized in 3 groups. The Brimonidine 
group (n=27) received a commercial preparation of Brimonidine 0.2% (Alphagan, Allergan 
Pharmaceuticals Ltd, Westport, Ireland). The Brinzolamide/Brimonidine group (n=27) 
received a commercial preparation of Brinzolamide 1%/Brimonidine 0.2% fixed combination 
(BBFC) (Simbrinza, Alcon Laboratories Ltd, Hertfordshire, United Kingdom). The Control 
group (n=25) received artificial tears (Tears Naturale II, Alcon Laboratories A.E.B.E., Athens 
Greece). Only one eye for each of the patients was enrolled in the study. Randomization was 
performed using the order of entrance in the study. In all groups the medication was 
administered as a single drop instillation, approximately 1 hour before Nd:YAG application. 
Exclusion criteria included patients with a baseline IOP greater than 21mmHg, glaucomatous 
eyes, intraocular surgery except from uncomplicated cataract surgery, previous 
photorefractive surgery, active ocular inflammation or infection. Additional exclusion criteria 
included patients under systemic administration of medication ns known to affect IOP, 
pregnant or breastfeeding women, and individuals with known hypersensitivity or 
contraindication to administration of the medications tested. Finally, an IOP increase >20 
mmHg from baseline at any time point of the study would require rescue treatment and was 
considered an exclusion criterion. All patients underwent a complete ophthalmic 
examination, including Goldmann applanation tonometry. The baseline IOP measurement 
was performed by a masked investigator (OM) approximately 1 hour before Nd:YAG 
application, just before instillation of the study medication. Pupillary dilation was performed 
by the instillation of a single drop of tropicamide 0.5% (Tropixal, Demo SA, Greece). All 


capsulotomies were performed by the same surgeon (CG) who was masked to treatment 
assignment, after application of 1 drop of proparacaine HCl 0.5% eye drops (Alcaine; Alcon 
Laboratories, Inc. Fort Worth, TX) as anaesthetic. Laser spots were applied through a 
widefield contact lens until a sufficient -approximately 4mm in diameter- capsule opening 
had been created. The total number of laser spots and the total amount of energy utilized 
were recorded. After Nd:YAG treatment all patients were prescribed dexamethasone 0.1% 
(Maxidex, Alcon Laboratories A.E.B.E., Athens Greece) qid for 1 week. Post Nd:YAG IOP 
measurements were performed at 1, 3 and 24 hours and at 1 week after capsulotomy, by 
the same investigator (OM) who had performed the baseline IOP measurements and was 
masked to the group assignments. Two consecutive IOP measurements were obtained, and 
the average value was calculated and used for analysis.  
 
Statistical Analysis  
The SPSS statistical package version 23.0 (Statistical Package for the Social Sciences, version 
23.0, SSPS Inc. Chicago, IL, USA) was used for statistical analysis. Repeated measures ANOVA 
was used to compare parametric values with Bonferroni post hoc test for within group 
comparisons. Categorized data were analyzed by the chi-square test and the Bonferroni 
correction was applied to avoid the risk of committing a type I error for between group 
comparisons. More precisely, the alpha-level of 0.05 was corrected for multiple comparisons 
involving the three outcome measures, resulting in an adjusted alpha of 0.017 (0.05/3). 
Statistical analysis was performed by an investigator blinded to the assignment of patients.