Efficacy and Safety of Dorzolamide-Timolol Combination vs. Brimonidine after ND:YAG Laser Capsulotomy for PCO
Introduction
Posterior capsular opacification (PCO) is the most common complication following a cataract surgery. Neodymium-doped yttrium aluminium garnet (Nd:YAG) laser capsulotomy is a safe and effective procedure that is commonly used to manage PCO. The procedure is often associated with increased intraocular pressure (IOP) within first 3 hours. Dorzolamide hydrochloride (2%) + timolol maleate (0.5%) and brimonidine (0.2%) are commonly used to keep IOP under control after capsulotomy.
Aim
To compare the impact of dorzolamide hydrochloride +timolol maleate vs. brimonidine on IOP, and to determine their adverse effects (AEs) following Nd:YAG laser capsulotomy.
Patient Profile
- Patients with posterior capsule opacification undergoing Nd:YAG laser capsulotomy after cataract surgery (n=90)
Methods
Study Design
·Randomized control trial
Treatment Strategy
- Patients were randomized into three groups as follows:
- Group 1: Treated with dorzolamide hydrochloride + timolol maleate; 1 hour before the procedure, and on the third hour of the first day and two times per day between the day 2 and 7
- Group 2: Treated with brimonidine; 1 hour before the procedure, and on the third hour of the first day and two times per day between the day 2 and 7
- Group 3: Control group, received no drug
- All patients were treated with dexamethasone eye drop at the third hour of the same day and four times per day from day 2 to day 7.
Outcomes
- Change in IOP
- Incidence of AEs
Results
- Brimonidine had a similar side effect profile to the fixed combination. Intraocular pressure on the first (p=0.87) and third days (p=0.124) were similar in group 1 (dorzolamide hydrochloride +timolol maleate), group 2 (brimonidine) and the control group.
- In Group 1 and Group 2, IOP was significantly lower than the control group on the seventh day (p=0.041). (Table 1).
|
IOP (mmHg) |
Group 1 (Brimonidine) |
Group 2 (Dorzolamide+Timolol) |
Group 3 (Control) |
P value |
|
Beginning |
13.9 |
14.0 |
13.8 |
0.101 |
|
Day 1 (third hour) |
13.51 |
13.1 |
14.1 |
0.87 |
|
Day 3 |
13.3 |
13.4 |
14.0 |
0.124 |
|
Day 7 |
13.2 |
13.4 |
14.6 |
0.041 |
- Various AEs including, burning, stinging, itching, hyperemia, and Tyndall rates did not differ significantly between Group 1, Group 2 and the control group.
- The incidence of watery eyes was less common in the brimonidine group vs. dorzolamide–timolol combination and the control groups on the seventh day (p=0.02). The chemosis rate on the third (p=0.04) and seventh (p=0.03) days was lower in brimonidine-treated patients.
Conclusion
- This is a first-of-its kind study that compared a combination of dorzolamide+timolol with brimonidine in patients undergoing ND:YAG laser capsulotomy, following cataract surgery.
- Both the drug regimens had similar efficacy for reducing IOP for routine cases.
- The incidence of AEs was similar for both the drug regimens, except that brimonidine was associated with lower rate of chemosis and watery eyes.
- Nevertheless, for patients at a greater risk of IOP attack, use of the dorzolamide +timolol combination would be more appropriate.
Eur J Ophthalmol. Nov 18, 2021 (Published Online); DOI: 10.1177/11206721211052163.
