Preventing a high rise in intraocular pressure after laser trabeculoplasty.

The high rise in pressure which sometimes follows laser trabeculoplasty is a serious and sight-threatening complication in patients with advanced glaucoma. In a previous study we found that patients undergoing laser trabeculoplasty were very unlikely to have a high rise in pressure if the initial pressure was less than 20 mmHg. In the present study a series of patients was given acetazolamide 500 mg immediately before laser trabeculoplasty if their pressures were greater than 20 mmHg. All patients were then monitored to see if this regime was effective in preventing a serious rise in intraocular pressure. Some of the patients with an initial pressure less than 20 mmHg still sustained a high rise in pressure after laser trabeculoplasty. A further series of patients was then given acetazolamide preoperatively and the postoperative rise in pressure was monitored two and 24 hours after trabeculoplasty. The acetazolamide prevented a high rise in pressure after laser trabeculoplasty in the majority of patients.