[The effect of brimonidine on postoperative hypertonia after an extracapsular cataract extraction]

We conducted a prospective study to determine the effect of topical administration of brimonidine tartrate 0.2% on postoperative intraocular pressure (IOP) spikes during the first 24 hours after an extracapsular cataract extraction.

In a placebo-controlled study, we randomized 40 consecutive normotensive eyes undergoing extracapsular cataract surgery into two treatment modalities. Twenty eyes (group A) received placebo and 20 eyes (group B) were given brimonidine tartate 0.2% drops twice the day before and twice on the day of the operation. IOP was measured at baseline (prior to surgery) and then 4, 6, 12 and 24 hours postoperatively.

Mean postoperative IOP was higher in the placebo group than in the brimonidine group at every time point studied. In both groups, peak elevation of mean IOP was recorded 6 hours after surgery. At that time, mean IOP was significantly higher in the placebo group (36.2+/-4.0 mmHg) than in the brimonidine group (24.7+/-3.8 mmHg) (p<0.001). A gradual reduction in IOP followed, yet with significantly higher values than those found preoperatively, even 12 hours after surgery (p<0.001). It was only the brimonidine group that achieved a near-to-normal mean IOP 24 hours after surgery (p>0.05). Four of the placebo group patients compared to 1 of the brimonidine group patients had an IOP higher than 40 mmHg 6 hours after surgery and therefore received additional therapy.

Prophylactic treatment with brimonidine tartrate 0.2% drops twice a day for 2 days is effective in reducing IOP spikes throughout the first 24 hours after an extracapsular cataract extraction.